MERCK & CO., INC., 10-K filed on 2/25/2025
Annual Report
v3.25.0.1
Cover Page - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Jan. 31, 2025
Jun. 28, 2024
Document Information [Line Items]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2024    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 1-6571    
Entity Registrant Name Merck & Co., Inc.    
Entity Address, Address Line One 126 East Lincoln Avenue    
Entity Address, City or Town Rahway    
Entity Address, State or Province NJ    
Entity Address, Postal Zip Code 07065    
City Area Code 908    
Local Phone Number 740-4000    
Entity Incorporation, State or Country Code NJ    
Entity Tax Identification Number 22-1918501    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   2,526,036,240  
Entity Public Float     $ 313,799
Documents Incorporated by Reference
Proxy Statement for the Annual Meeting of Shareholders to be held May 27, 2025, to be filed with the
Securities and Exchange Commission within 120 days after the close of the fiscal year covered by this report
   
Amendment Flag false    
Document Fiscal Year Focus 2024    
Document Fiscal Period Focus FY    
Entity Central Index Key 0000310158    
Common Stock ($0.50 par value)      
Document Information [Line Items]      
Title of 12(b) Security Common Stock ($0.50 par value)    
Trading Symbol MRK    
Security Exchange Name NYSE    
1.875% Notes due 2026      
Document Information [Line Items]      
Title of 12(b) Security 1.875% Notes due 2026    
Trading Symbol MRK/26    
Security Exchange Name NYSE    
3.250% Notes due 2032      
Document Information [Line Items]      
Title of 12(b) Security 3.250% Notes due 2032    
Trading Symbol MRK/32    
Security Exchange Name NYSE    
2.500% Notes due 2034      
Document Information [Line Items]      
Title of 12(b) Security 2.500% Notes due 2034    
Trading Symbol MRK/34    
Security Exchange Name NYSE    
1.375% Notes due 2036      
Document Information [Line Items]      
Title of 12(b) Security 1.375% Notes due 2036    
Trading Symbol MRK 36A    
Security Exchange Name NYSE    
3.500% Notes due 2037      
Document Information [Line Items]      
Title of 12(b) Security 3.500% Notes due 2037    
Trading Symbol MRK/37    
Security Exchange Name NYSE    
3.700% Notes due 2044      
Document Information [Line Items]      
Title of 12(b) Security 3.700% Notes due 2044    
Trading Symbol MRK/44    
Security Exchange Name NYSE    
3.750% Notes due 2054      
Document Information [Line Items]      
Title of 12(b) Security 3.750% Notes due 2054    
Trading Symbol MRK/54    
Security Exchange Name NYSE    
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Audit Information
12 Months Ended
Dec. 31, 2024
Audit Information [Abstract]  
Auditor Name PricewaterhouseCoopers LLP
Auditor Location Florham Park, New Jersey
Auditor Firm ID 238
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Consolidated Statement of Income - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Income Statement [Abstract]      
Sales $ 64,168 $ 60,115 $ 59,283
Costs, Expenses and Other      
Cost of sales 15,193 16,126 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Restructuring costs 309 599 337
Other (income) expense, net (24) 466 1,501
Total costs, expenses and other 44,232 58,226 42,839
Income Before Taxes 19,936 1,889 16,444
Taxes on Income 2,803 1,512 1,918
Net Income 17,133 377 14,526
Less: Net Income Attributable to Noncontrolling Interests 16 12 7
Net Income Attributable to Merck & Co., Inc. $ 17,117 $ 365 $ 14,519
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share) $ 6.76 $ 0.14 $ 5.73
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share) $ 6.74 $ 0.14 $ 5.71
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Consolidated Statement of Comprehensive Income (Loss) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Statement of Comprehensive Income [Abstract]      
Net Income Attributable to Merck & Co., Inc. $ 17,117 $ 365 $ 14,519
Other Comprehensive Income (Loss) Net of Taxes:      
Net unrealized income (loss) on derivatives, net of reclassifications 266 (97) (71)
Benefit plan net gain (loss) and prior service credit (cost), net of amortization 466 (385) 335
Cumulative translation adjustment (516) 89 (603)
Other comprehensive income (loss), net of taxes 216 (393) (339)
Comprehensive Income (Loss) Attributable to Merck & Co., Inc. $ 17,333 $ (28) $ 14,180
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Consolidated Balance Sheet - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Current Assets    
Cash and cash equivalents $ 13,242 $ 6,841
Short-term investments 447 252
Accounts receivable (net of allowance for doubtful accounts of $89 in 2024 and $88 in 2023) 10,278 10,349
Inventories (excludes inventories of $4,193 in 2024 and $3,348 in 2023 classified in Other assets - see Note 7) 6,109 6,358
Other current assets 8,706 8,368
Total current assets 38,782 32,168
Investments 463 252
Property, Plant and Equipment (at cost)    
Land 307 326
Buildings 16,360 14,966
Machinery, equipment and office furnishings 18,283 17,763
Construction in progress 7,984 8,262
Property, plant and equipment (at cost) 42,934 41,317
Less: accumulated depreciation 19,155 18,266
Property, plant and equipment, net 23,779 23,051
Goodwill 21,668 21,197
Other Intangibles, Net 16,370 18,011
Other Assets 16,044 11,996
Total Assets 117,106 106,675
Current Liabilities    
Loans payable and current portion of long-term debt 2,649 1,372
Trade accounts payable 4,079 3,922
Accrued and other current liabilities 15,694 15,766
Income taxes payable 3,914 2,649
Dividends payable 2,084 1,985
Total current liabilities 28,420 25,694
Long-Term Debt 34,462 33,683
Deferred Income Taxes 1,387 871
Other Noncurrent Liabilities 6,465 8,792
Merck & Co., Inc. Stockholders’ Equity    
Common stock, $0.50 par value Authorized - 6,500,000,000 shares Issued - 3,577,103,522 shares in 2024 and 2023 1,788 1,788
Other paid-in capital 44,704 44,509
Retained earnings 63,069 53,895
Accumulated other comprehensive loss (4,945) (5,161)
Stockholders' equity before deduction for treasury stock 104,616 95,031
Less treasury stock, at cost: 1,049,466,187 shares in 2024 and 1,045,470,249 shares in 2023 58,303 57,450
Total Merck & Co., Inc. stockholders’ equity 46,313 37,581
Noncontrolling Interests 59 54
Total equity 46,372 37,635
Total Liabilities and Equity $ 117,106 $ 106,675
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Consolidated Balance Sheet (Parenthetical) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Statement of Financial Position [Abstract]    
Allowance for doubtful accounts $ 89 $ 88
Inventory classified in Other assets $ 4,193 $ 3,348
Common stock, par value (in dollars per share) $ 0.50 $ 0.50
Common stock, authorized (in shares) 6,500,000,000 6,500,000,000
Common stock, shares issued (in shares) 3,577,103,522 3,577,103,522
Treasury stock, shares (in shares) 1,049,466,187 1,045,470,249
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Consolidated Statement of Equity - USD ($)
$ in Millions
Total
Common Stock
Other Paid-In Capital
Retained Earnings
Accumulated Other Comprehensive Loss
Treasury Stock
Non- controlling Interests
Beginning balance at Dec. 31, 2021 $ 38,257 $ 1,788 $ 44,238 $ 53,696 $ (4,429) $ (57,109) $ 73
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net Income Attributable to Merck & Co., Inc. 14,519     14,519      
Other comprehensive income (loss), net of taxes (339)       (339)    
Cash dividends declared on common stock (7,134)     (7,134)      
Net income attributable to noncontrolling interests 7           7
Distributions attributable to noncontrolling interests (13)           (13)
Share-based compensation plans and other 761   141     620  
Ending balance at Dec. 31, 2022 46,058 1,788 44,379 61,081 (4,768) (56,489) 67
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net Income Attributable to Merck & Co., Inc. 365     365      
Other comprehensive income (loss), net of taxes (393)       (393)    
Cash dividends declared on common stock (7,551)     (7,551)      
Treasury stock shares purchased (1,346)         (1,346)  
Net income attributable to noncontrolling interests 12           12
Distributions attributable to noncontrolling interests (25)           (25)
Share-based compensation plans and other 515   130     385  
Ending balance at Dec. 31, 2023 37,635 1,788 44,509 53,895 (5,161) (57,450) 54
Increase (Decrease) in Stockholders' Equity [Roll Forward]              
Net Income Attributable to Merck & Co., Inc. 17,117     17,117      
Other comprehensive income (loss), net of taxes 216       216    
Cash dividends declared on common stock (7,943)     (7,943)      
Treasury stock shares purchased (1,306)         (1,306)  
Net income attributable to noncontrolling interests 16           16
Distributions attributable to noncontrolling interests (12)           (12)
Share-based compensation plans and other 649   195     453 1
Ending balance at Dec. 31, 2024 $ 46,372 $ 1,788 $ 44,704 $ 63,069 $ (4,945) $ (58,303) $ 59
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Consolidated Statement of Equity (Parenthetical) - $ / shares
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Statement of Stockholders' Equity [Abstract]      
Common stock, dividends declared (in dollars per share) $ 3.12 $ 2.96 $ 2.80
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Consolidated Statement of Cash Flows - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Cash Flows from Operating Activities      
Net income $ 17,133 $ 377 $ 14,526
Adjustments to reconcile net income to net cash provided by operating activities:      
Amortization 2,395 2,044 2,085
Depreciation 2,104 1,828 1,824
Intangible asset impairment charges 39 792 1,749
(Income) loss from investments in equity securities, net (14) (340) 1,419
Charges for certain research and development asset acquisitions 3,456 11,409 0
Deferred income taxes (1,249) (1,899) (1,568)
Share-based compensation 761 645 541
Other 510 355 1,301
Net changes in assets and liabilities:      
Accounts receivable (244) (1,148) (644)
Inventories (835) (816) (161)
Trade accounts payable 182 (380) (289)
Accrued and other current liabilities (2,328) 1,783 (50)
Income taxes payable 1,023 214 380
Noncurrent liabilities (49) 456 (545)
Other (1,416) (2,314) (1,473)
Net Cash Provided by Operating Activities 21,468 13,006 19,095
Cash Flows from Investing Activities      
Capital expenditures (3,372) (3,863) (4,388)
Purchases of securities and other investments (519) (955) (1,204)
Proceeds from sale of Seagen Inc. common stock 0 1,145 0
Proceeds from sales of securities and other investments 377 1,658 721
Acquisition of Eyebiotech Limited, net of cash acquired (1,344) 0 0
Acquisition of Elanco Animal Health Incorporated aqua business (1,303) 0 0
Acquisition of Harpoon Therapeutics, Inc., net of cash acquired (746) 0 0
Acquisition of MK-1045 from Curon Pharmaceutical (700) 0 0
Acquisition of Prometheus Biosciences, Inc., net of cash acquired 0 (10,705) 0
Acquisition of Imago BioSciences Inc., net of cash acquired 0 (1,327) 0
Other (127) (36) (89)
Net Cash Used in Investing Activities (7,734) (14,083) (4,960)
Cash Flows from Financing Activities      
Payments on debt (1,290) (1,755) (2,251)
Proceeds from issuance of debt 3,599 5,939 0
Purchases of treasury stock (1,306) (1,346) 0
Dividends paid to stockholders (7,840) (7,445) (7,012)
Proceeds from exercise of stock options 177 125 384
Other (372) (328) (240)
Net Cash Used in Financing Activities (7,032) (4,810) (9,119)
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash (293) 23 (410)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash 6,409 (5,864) 4,606
Cash, Cash Equivalents and Restricted Cash at Beginning of Year (includes $68, $79 and $71 of restricted cash at January 1, 2024, 2023 and 2022, respectively, included in Other current assets) 6,909 12,773 8,167
Cash, Cash Equivalents and Restricted Cash at End of Year (includes $76, $68 and $79 of restricted cash at December 31, 2024, 2023 and 2022, respectively, included in Other current assets) $ 13,318 $ 6,909 $ 12,773
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Consolidated Statement of Cash Flows (Parenthetical) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Statement of Cash Flows [Abstract]        
Cash, cash equivalents, and restricted cash $ 76 $ 68 $ 79 $ 71
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Nature of Operations
12 Months Ended
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Nature of Operations Nature of Operations
Merck & Co., Inc. (Merck or the Company) is a global health care company that delivers innovative health solutions through its prescription medicines, including biologic therapies, vaccines and animal health products. The Company’s operations are principally managed on a product basis and include two operating segments, Pharmaceutical and Animal Health, both of which are reportable segments.
The Pharmaceutical segment includes human health pharmaceutical and vaccine products. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Human health vaccine products consist of preventive pediatric, adolescent and adult vaccines. The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities.
The Animal Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners.
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Summary of Accounting Policies
12 Months Ended
Dec. 31, 2024
Accounting Policies [Abstract]  
Summary of Accounting Policies Summary of Accounting Policies
Principles of Consolidation — The consolidated financial statements include the accounts of the Company and all of its subsidiaries in which a controlling interest is maintained. Intercompany balances and transactions are eliminated. Controlling interest is determined by majority ownership interest and the absence of substantive third-party participating rights or, in the case of variable interest entities, by majority exposure to expected losses, residual returns or both. For those consolidated subsidiaries where Merck ownership is less than 100%, the outside shareholders’ interests are shown as Noncontrolling interests in equity. Investments in affiliates over which the Company has significant influence but not a controlling interest, such as interests in entities owned equally by the Company and a third party that are under shared control, are carried on the equity method basis.
Acquisitions — In a business combination, the acquisition method of accounting requires that the assets acquired and liabilities assumed be recorded as of the date of the acquisition at their respective fair values with limited exceptions. Assets acquired and liabilities assumed in a business combination that arise from contingencies are generally recognized at fair value. If fair value cannot be determined, the asset or liability is recognized if probable and reasonably estimable; if these criteria are not met, no asset or liability is recognized. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Accordingly, the Company may be required to value assets at fair value measures that do not reflect the Company’s intended use of those assets. Any excess of the purchase price (consideration transferred) over the estimated fair values of net assets acquired is recorded as goodwill. Transaction costs and costs to restructure the acquired company are expensed as incurred. The operating results of the acquired business are reflected in the Company’s consolidated financial statements after the date of the acquisition.
If the Company determines the assets acquired do not meet the definition of a business under the acquisition method of accounting, the transaction will be accounted for as an acquisition of assets rather than a business combination and, therefore, no goodwill will be recorded. In an asset acquisition, acquired in-process research and development (IPR&D) with no alternative future use is charged to expense and contingent consideration is not recognized at the acquisition date.
Foreign Currency Translation — The net assets of international subsidiaries where the local currencies have been determined to be the functional currencies are translated into U.S. dollars using current exchange rates and results of operations are translated at average exchange rates. The U.S. dollar effects that arise from translating the net assets of these subsidiaries at changing rates are recorded in Other Comprehensive Income (OCI) and remain in Accumulated other comprehensive loss (AOCL) until either the sale or complete or substantially complete liquidation of the subsidiary. For those subsidiaries that operate in highly inflationary economies and for those subsidiaries where the U.S. dollar has been determined to be the functional currency, non-monetary foreign currency
assets and liabilities are translated using historical rates, while monetary assets and liabilities are translated at current rates, with the U.S. dollar effects of rate changes included in Other (income) expense, net.
Cash Equivalents — Cash equivalents are comprised of certain highly liquid investments with original maturities of less than three months.
Inventories — Inventories are valued at the lower of cost or net realizable value. The cost of a substantial majority of U.S. human health inventories is determined using the last-in, first-out (LIFO) method for both financial reporting and tax purposes. The cost of all other inventories is determined using the first-in, first-out (FIFO) method. Inventories consist of currently marketed products, as well as certain inventories produced in preparation for product launches that are considered by the Company to be probable of obtaining regulatory approval. In evaluating the recoverability of inventories produced in preparation for product launches, the Company considers the likelihood that revenue will be obtained from the future sale of the related inventory together with the status of the product during the research and regulatory approval process.
Investments — Investments in marketable debt securities classified as available-for-sale are reported at fair value. Fair values of the Company’s investments in marketable debt securities are determined using quoted market prices in active markets for identical assets or quoted prices for similar assets or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Changes in fair value that are not impairment related are reported net of taxes in OCI. The Company considers available evidence in evaluating potential impairments of its investments in marketable debt securities, including the extent to which fair value is less than cost, whether an allowance for credit loss is required, as well as adverse factors that could affect the value of the securities. An impairment has occurred if the Company does not expect to recover the entire amortized cost basis of the marketable debt security. If the Company does not intend to sell the impaired debt security, and it is not more likely than not it will be required to sell the debt security before the recovery of its amortized cost basis, the amount of the impairment recognized in earnings, recorded in Other (income) expense, net, is limited to the portion attributed to credit loss. The remaining portion of the impairment related to other factors is recognized in OCI. Realized gains and losses for debt securities are included in Other (income) expense, net.
Investments in publicly traded equity securities are reported at fair value as determined using quoted market prices in active markets for identical assets or quoted prices for similar assets or other inputs that are observable or can be corroborated by observable market data. Changes in fair value are included in Other (income) expense, net. Unrealized gains and losses from investments that are directly owned are determined at the end of the reporting period. Gains and losses from ownership interests in investment funds, which are accounted for as equity method investments, are reported on a one quarter lag. Investments in equity securities without readily determinable fair values are recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, minus impairments. Such adjustments are recognized in Other (income) expense, net. Realized gains and losses for equity securities are included in Other (income) expense, net.
Revenue Recognition — Recognition of revenue requires evidence of a contract, probable collection of sales proceeds and completion of substantially all performance obligations. Merck acts as the principal in substantially all of its customer arrangements and therefore records revenue on a gross basis. The majority of the Company’s contracts related to the Pharmaceutical and Animal Health segments have a single performance obligation - the promise to transfer goods. Shipping is considered immaterial in the context of the overall customer arrangement and damages or loss of goods in transit are rare. Therefore, shipping is not deemed a separately recognized performance obligation.
The vast majority of revenues from sales of products are recognized at a point in time when control of the goods is transferred to the customer, which the Company has determined is when title and risks and rewards of ownership transfer to the customer and the Company is entitled to payment. The Company recognizes revenue from the sales of vaccines to the U.S. federal government for placement into vaccine stockpiles in accordance with Securities and Exchange Commission (SEC) Interpretation, Commission Guidance Regarding Accounting for Sales of Vaccines and BioTerror Countermeasures to the Federal Government for Placement into the Pediatric Vaccine Stockpile or the Strategic National Stockpile. This interpretation allows companies to recognize revenue for sales of vaccines into U.S. government stockpiles even though these sales might not meet the criteria for revenue recognition under other accounting guidance. For certain services in the Animal Health segment, revenue is recognized over time, generally ratably over the contract term as services are provided. These service revenues are not material.
The nature of the Company’s business gives rise to several types of variable consideration including discounts and returns, which are estimated at the time of sale generally using the expected value method, although the most likely amount method is used for prompt pay discounts.
In the U.S., sales discounts are issued to customers at the point-of-sale, through an intermediary wholesaler (known as chargebacks), or in the form of rebates. Additionally, sales are generally made with a limited right of return under certain conditions. Revenues are recorded net of provisions for sales discounts and returns, which are established at the time of sale. In addition, if collection of accounts receivable is expected to be in excess of one year, sales are recorded net of time value of money discounts, which have not been material.
The U.S. provision for aggregate customer discounts covering chargebacks and rebates was $13.3 billion in 2024, $12.5 billion in 2023 and $12.3 billion in 2022. Chargebacks are discounts that occur when a contracted customer purchases through an intermediary wholesaler. The wholesaler then charges the Company back for the difference between the price initially paid by the wholesaler and the contract price agreed to between Merck and the customer. The provision for chargebacks is based on expected sell-through levels by the Company’s wholesale customers to contracted customers, as well as estimated wholesaler inventory levels. Rebates are amounts owed based upon definitive contractual agreements or legal requirements with private sector and public sector (Medicaid and Medicare Part D) benefit providers after the final dispensing of the product to a benefit plan participant. The provision for rebates is based on expected patient usage, as well as inventory levels in the distribution channel to determine the contractual obligation to the benefit providers. The Company uses historical customer segment utilization mix, sales forecasts, changes to product mix and price, inventory levels in the distribution channel, government pricing calculations and prior payment history in order to estimate the expected provision. Amounts accrued for aggregate customer discounts are evaluated on a quarterly basis through comparison of information provided by the wholesalers, health maintenance organizations, pharmacy benefit managers, federal and state agencies, and other customers to the amounts accrued. The accrued balances relative to the provisions for chargebacks and rebates included in Accounts receivable and Accrued and other current liabilities were $293 million and $2.2 billion, respectively, at December 31, 2024 and were $188 million and $2.3 billion, respectively, at December 31, 2023.
Outside of the U.S., variable consideration in the form of discounts and rebates are a combination of commercially-driven discounts in highly competitive product classes, discounts required to gain or maintain reimbursement, or legislatively mandated rebates. In certain European countries, legislatively mandated rebates are calculated based on an estimate of the government’s total unbudgeted spending and the Company’s specific payback obligation. Rebates may also be required based on specific product sales thresholds. The Company applies an estimated factor against its actual invoiced sales to represent the expected level of future discount or rebate obligations associated with the sale.
The Company maintains a returns policy that allows its U.S. pharmaceutical customers to return product within a specified period prior to and subsequent to the expiration date (generally, three to six months before and 12 months after product expiration). The estimate of the provision for returns is based upon historical experience with actual returns. Additionally, the Company considers factors such as levels of inventory in the distribution channel, product dating and expiration period, whether products have been discontinued, entrance in the market of generic or other competition, changes in formularies or launch of over-the-counter products, among others. Outside of the U.S., returns are only allowed in certain countries on a limited basis.
Merck’s payment terms for U.S. pharmaceutical customers are typically 36 days from receipt of invoice and for U.S. animal health customers are typically 30 days from receipt of invoice; however, certain products have longer payment terms, including Keytruda (pembrolizumab), which has payment terms of 90 days. Payment terms for vaccine sales in the U.S. typically range from 30 days to 60 days. Outside of the U.S., payment terms are typically 30 days to 90 days, although certain markets have longer payment terms.
See Note 18 for disaggregated revenue disclosures.
Depreciation — Depreciation is provided over the estimated useful lives of the assets, principally using the straight-line method. For tax purposes, accelerated tax methods are used. The estimated useful lives primarily range from 25 to 45 years for Buildings, and from 3 to 15 years for Machinery, equipment and office furnishings. Depreciation expense was $2.1 billion in 2024, $1.8 billion in 2023 and $1.8 billion in 2022.
Advertising and Promotion Costs — Advertising and promotion costs are expensed as incurred. The Company recorded advertising and promotion expenses of $2.4 billion in 2024, $2.3 billion in 2023 and $2.2 billion in 2022.
Software Capitalization — The Company capitalizes certain costs incurred in connection with obtaining or developing internal-use software including external direct costs of material and services, and payroll costs for employees directly involved with the software development. These costs are included in Property, plant and equipment. In addition, the Company capitalizes certain costs incurred to implement a cloud computing arrangement
that is considered a service agreement, which are included in Other Assets. Capitalized software costs are being amortized over periods ranging from 2 to 10 years, with the longer lives generally associated with enterprise-wide projects implemented over multiple years. Costs incurred during the preliminary project stage and post-implementation stage, as well as maintenance and training costs, are expensed as incurred.
Goodwill — Goodwill represents the excess of the consideration transferred over the fair value of net assets acquired in a business combination. Goodwill is assigned to reporting units and evaluated for impairment at least annually, or more frequently if impairment indicators exist, by first assessing qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If the Company concludes it is more likely than not that the fair value of a reporting unit is less than its carrying amount, a quantitative fair value test is performed. If the carrying value of a reporting unit is greater than its fair value, a goodwill impairment charge will be recorded for the difference (up to the carrying value of goodwill).
Acquired Intangibles — Intangibles acquired in a business combination include product rights, trade names and patents, licenses and other, which are initially recorded at fair value, assigned an estimated useful life, and amortized primarily on a straight-line basis over their estimated useful lives ranging from 2 to 24 years. The Company periodically evaluates whether current facts or circumstances indicate that the carrying values of its acquired intangibles may not be recoverable. If such circumstances are determined to exist, an estimate of the undiscounted future cash flows of these assets, or appropriate asset groupings, is compared to the carrying value to determine whether an impairment exists. If the asset is determined to be impaired, the loss is measured based on the difference between the carrying value of the intangible asset and its fair value, which is determined based on the net present value of estimated future cash flows.
Acquired In-Process Research and Development — IPR&D that the Company acquires in conjunction with a business combination represents the fair value assigned to incomplete research projects which, at the time of acquisition, have not reached technological feasibility. The amounts are capitalized and are accounted for as indefinite-lived intangible assets, subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each IPR&D project, Merck will make a determination as to the then-useful life of the intangible asset, generally determined by the period in which the substantial majority of the cash flows are expected to be generated, and begin amortization. The Company evaluates IPR&D for impairment at least annually, or more frequently if impairment indicators exist, by performing a quantitative test that compares the fair value of the IPR&D intangible asset with its carrying value. If the fair value is less than the carrying amount, an impairment loss is recognized in operating results.
Contingent Consideration for Business Combinations — Certain of the Company’s acquisitions involve the potential for future payment of consideration that is contingent upon the achievement of performance milestones, including product development milestones and royalty payments on future product sales. If the transaction is accounted for as a business combination, the fair value of contingent consideration liabilities is determined at the acquisition date using unobservable inputs. These inputs include the estimated amount and timing of projected cash flows, the probability of success (achievement of the contingent event) and the risk-adjusted discount rate used to present value the probability-weighted cash flows. Subsequent to the acquisition date, at each reporting period until the contingency is resolved, the contingent consideration liability is remeasured at current fair value with changes (either expense or income) recorded in earnings. Significant events that increase or decrease the probability of achieving development and regulatory milestones or that increase or decrease projected cash flows will result in corresponding increases or decreases in the fair values of the related contingent consideration obligations.
Research and Development — Research and development is expensed as incurred. Nonrefundable advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Research and development expenses include restructuring costs and IPR&D impairment charges. In addition, research and development expenses include expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration associated with IPR&D assets. Research and development expenses also include upfront and milestone payments related to asset acquisitions and licensing transactions involving clinical development programs that have not yet received regulatory approval.
Collaborative Arrangements — Merck has entered into collaborative arrangements that provide the Company with varying rights to develop, produce and market products together with its collaborative partners. When Merck is the principal on sales transactions with third parties, the Company recognizes sales, cost of sales and selling, general and administrative expenses on a gross basis. Profit sharing amounts it pays to its collaborative partners are recorded within Cost of sales. When the collaborative partner is the principal on sales transactions with third parties, the Company records profit sharing amounts received from its collaborative partners as alliance revenue
(within Sales). Alliance revenue is recorded net of cost of sales and includes an adjustment to share commercialization costs between the partners in accordance with the collaboration agreement. The adjustment is determined by comparing the commercialization costs Merck has incurred directly and reported within Selling, general and administrative expenses with the costs the collaborative partner has incurred. Research and development costs Merck incurs related to collaborations are recorded within Research and development expenses. Cost reimbursements to the collaborative partner or payments received from the collaborative partner to share these costs pursuant to the terms of the collaboration agreements are recorded as increases or decreases to Research and development expenses.
In addition, the terms of the collaboration agreements may require the Company to make payments based upon the achievement of certain developmental, regulatory approval or commercial milestones. Upfront and milestone payments payable by Merck to collaborative partners prior to regulatory approval are expensed as incurred and included in Research and development expenses. Payments due to collaborative partners upon or subsequent to regulatory approval are capitalized and amortized to Cost of sales over the estimated useful life of the corresponding intangible asset, provided that future cash flows support the amounts capitalized. Sales-based milestones payable by Merck to collaborative partners are accrued and capitalized, subject to cumulative amortization catch-up, when determined by the Company to be probable of being achieved based on future sales forecasts. The amortization catch-up is calculated either from the time of the first regulatory approval for products that were unapproved at the time the collaboration was formed or, for new indications of approved products, from the time of the formation of the collaboration. The related intangible asset that is recognized is amortized to Cost of sales over its remaining useful life, subject to impairment testing.
Share-Based Compensation — The Company expenses all share-based payments to employees over the requisite service period based on the grant-date fair value of the awards.
Restructuring Costs — The Company records liabilities for costs associated with exit or disposal activities in the period in which the liability is incurred. In accordance with existing benefit arrangements, future employee termination costs to be incurred in conjunction with involuntary separations are accrued when such separations are probable and estimable. When accruing these costs, the Company will recognize the amount within a range of costs that is the best estimate within the range. When no amount within the range is a better estimate than any other amount, the Company recognizes the minimum amount within the range. Costs for one-time termination benefits in which the employee is required to render service until termination in order to receive the benefits are recognized ratably over the future service period.
Contingencies and Legal Defense Costs — The Company records accruals for contingencies and legal defense costs expected to be incurred in connection with a loss contingency when it is probable that a liability has been incurred and the amount can be reasonably estimated.
Taxes on Income — Deferred taxes are recognized for the future tax effects of temporary differences between financial and income tax reporting based on enacted tax laws and rates. The Company evaluates tax positions to determine whether the benefits of tax positions are more likely than not of being sustained upon audit based on the technical merits of the tax position. For tax positions that are more likely than not of being sustained upon audit, the Company recognizes the amount of the benefit that is greater than 50% likely of being realized upon ultimate settlement in the financial statements. For tax positions that are not more likely than not of being sustained upon audit, the Company does not recognize any portion of the benefit in the financial statements. The Company recognizes interest and penalties associated with uncertain tax positions as a component of Taxes on Income. The Company accounts for the tax effects of the tax on global intangible low-taxed income (GILTI) of certain foreign subsidiaries in the income tax provision in the period the tax arises. The Company’s policy for releasing disproportionate income tax effects from AOCL is to utilize the item-by-item approach.
Reclassifications — Certain reclassifications have been made to prior year amounts to conform to the current year presentation.
Use of Estimates — The consolidated financial statements are prepared in conformity with accounting principles generally accepted in the U.S. (GAAP) and, accordingly, include certain amounts that are based on management’s best estimates and judgments. Estimates are used when accounting for amounts recorded in connection with acquisitions, including initial fair value determinations of assets and liabilities in a business combination (primarily IPR&D, other intangible assets and contingent consideration), as well as subsequent fair value measurements. Additionally, estimates are used in determining such items as provisions for sales discounts, rebates and returns, depreciable and amortizable lives, recoverability of inventories, including those produced in preparation for product launches, amounts recorded for contingencies, environmental liabilities, accruals for contingent sales-
based milestone payments and other reserves, pension and other postretirement benefit plan assumptions, share-based compensation assumptions, restructuring costs, impairments of long-lived assets (including intangible assets and goodwill) and investments, and taxes on income. Because of the uncertainty inherent in such estimates, actual results may differ from these estimates.
Recently Adopted Accounting Standards — In August 2023, the Financial Accounting Standards Board (FASB) issued amended guidance that requires a newly formed joint venture to recognize and initially measure its assets and liabilities at fair value upon formation. The amended guidance includes exceptions to fair value measurement that are consistent with the accounting for business combinations guidance. The Company adopted the guidance effective July 1, 2024 on a prospective basis. There was no impact to the Company’s consolidated financial statements upon adoption.
In November 2023, the FASB issued guidance intended to improve reportable segment disclosure requirements, primarily through expanded disclosures for significant segment expenses. The Company adopted the guidance effective for the 2024 annual period. The guidance resulted in incremental disclosures to the Company’s segment reporting disclosures. See Note 18 for further details.
Recently Issued Accounting Standards Not Yet Adopted — In December 2023, the FASB issued guidance intended to improve the transparency of income tax disclosures by requiring consistent categories and disaggregation of information in the effective income tax rate reconciliation and income taxes paid disclosures by jurisdiction. The guidance also includes other amendments to improve the effectiveness of income tax disclosures by removing certain previously required disclosures. The guidance is effective for 2025 annual reporting. The guidance will result in incremental disclosures within the footnotes to the Company’s financial statements.
In November 2024, the FASB issued guidance intended to improve financial reporting by requiring entities to disclose additional information about specific expense categories at interim and annual reporting periods. The guidance is effective for 2027 annual reporting and 2028 interim reporting. Early adoption is permitted. The guidance, which can be applied on a prospective or retrospective basis, will result in incremental disclosures within the footnotes to the Company’s financial statements.
v3.25.0.1
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements
12 Months Ended
Dec. 31, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]  
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements Acquisitions, Divestitures, Research Collaborations and Licensing Agreements
The Company continues to pursue acquisitions and the establishment of external alliances such as research collaborations and licensing agreements to complement its internal research capabilities. These arrangements often include upfront payments; expense reimbursements or payments to the third party; milestone, royalty or profit share arrangements contingent upon the occurrence of certain future events linked to the success of the asset in development; and can also include option and continuation payments. The Company also reviews its marketed products and pipeline to examine candidates which may provide more value through out-licensing and, as part of its portfolio assessment process, may also divest certain assets. Pro forma financial information for acquired businesses is not presented if the historical financial results of the acquired entity are not significant when compared with the Company’s financial results.
Recent Transactions
In January 2025, Merck and WuXi Vaccines, a wholly owned subsidiary of WuXi Biologics, entered into a definitive agreement pursuant to which Merck will acquire WuXi Vaccines’ facility in Dundalk, Ireland for a payment of approximately $440 million at closing. The transaction is expected to close in the first quarter of 2025, subject to the satisfaction of customary closing conditions. There are no future contingent payments associated with the acquisition.
2024 Transactions
In December 2024, Merck closed an exclusive global license to develop, manufacture and commercialize MK-2010 (LM-299), a novel investigational PD-1/vascular endothelial growth factor (VEGF) bispecific antibody from LaNova Medicines Ltd (LaNova). Merck recorded a charge of $588 million to Research and development expenses in 2024 for the upfront payment, which was made in January 2025. LaNova is also eligible to receive $300 million upon technology transfer, which is anticipated to be completed in 2025, as well as future contingent developmental milestone payments of up to $140 million, regulatory milestone payments of up to $860 million and sales-based milestone payments of up to $1.4 billion.
Also in December 2024, Merck closed an exclusive global license to develop, manufacture and commercialize MK-4082 (HS-10535), an investigational preclinical oral small molecule GLP-1 receptor agonist from Hansoh Pharma (Hansoh). Merck recorded a charge of $112 million to Research and development expenses in 2024 for the upfront payment, which was made in February 2025. Hansoh is also eligible to receive future contingent
development-related milestone payments of up to $115 million, regulatory milestone payments of up to $315 million and sales-based milestone payments of up to $1.47 billion, as well as tiered royalties ranging from a high-single-digit rate to a low-double-digit rate on future net sales of MK-4082 (HS-10535), if approved. Under the agreement, Hansoh may co-promote or solely commercialize MK-4082 (HS-10535) in Chinese mainland, Hong Kong and Macau, subject to certain conditions.
In September 2024, Merck acquired MK-1045 (formally CN201), a novel investigational clinical-stage bispecific antibody for the treatment of B-cell associated diseases, from Curon Biopharmaceutical (Curon) for an upfront payment of $700 million. In addition, Curon is eligible to receive future contingent developmental milestone payments of up to $300 million and regulatory milestone payments of up to $300 million. The transaction was accounted for as an asset acquisition. Merck recorded a charge of $750 million (reflecting the upfront payment and other related costs) to Research and development expenses in 2024 related to the execution of the transaction. In connection with the agreement, Merck is also obligated to pay a third party future contingent developmental, regulatory and sales-based milestone payments of up to $128 million in the aggregate, as well as tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales of MK-1045, if approved.
In July 2024, Merck acquired the aqua business of Elanco Animal Health Incorporated (Elanco aqua business) for total consideration of $1.3 billion. The Elanco aqua business consists of an innovative portfolio of medicines and vaccines, nutritionals and supplements for aquatic species; two related aqua manufacturing facilities in Canada and Vietnam; as well as a research facility in Chile. The acquisition broadens Animal Health’s aqua portfolio with products, such as Clynav, a new generation DNA-based vaccine that protects Atlantic salmon against pancreas disease, and Imvixa, an anti-parasitic sea lice treatment. This acquisition also brings a portfolio of water treatment products for warm water production, complementing Animal Health’s warm water vaccine portfolio. In addition to these products, the DNA-based vaccine technology that is a part of the business has the potential to accelerate the development of novel vaccines to address the unmet needs of the aqua industry. There are no contingent payments associated with the acquisition, which was accounted for as a business combination.
The estimated fair values of assets acquired and liabilities assumed from the Elanco aqua business are as follows:
July 9, 2024
Inventories
$65 
Property, plant and equipment
66
Product rights - Clynav (useful life 15 years) (1)
340
Other product rights (useful lives 15 years) (1)
291
Other assets and liabilities, net23 
Total identifiable net assets785 
Goodwill (2)
518
Consideration transferred$1,303 
(1)    The estimated fair values of Clynav and other product rights were determined using an income approach, specifically the multi-period excess earnings method. The future probability-weighted net cash flows were discounted to present value utilizing a discount rate of 8.5%. Actual cash flows are likely to be different than those assumed.
(2)    The goodwill recognized is largely attributable to anticipated synergies expected to arise after the acquisition and was allocated to the Animal Health segment. The goodwill is expected to be deductible for tax purposes.
Also in July 2024, Merck acquired Eyebiotech Limited (EyeBio), a privately held ophthalmology-focused biotechnology company, for $1.2 billion (including payments to settle share-based equity awards) and also incurred $207 million of transaction costs. The acquisition agreement also provides for former EyeBio shareholders to receive future contingent developmental milestone payments of up to $200 million (of which $100 million was triggered and paid in 2024 as noted below), regulatory milestone payments of up to $1.0 billion and sales-based milestone payments of up to $500 million. EyeBio’s development work focused on candidates for the prevention and treatment of vision loss associated with retinal vascular leakage, a known risk factor for retinal diseases. EyeBio’s lead candidate, MK-3000 (formerly EYE103), is an investigational, potentially first-in-class tetravalent, tri-specific antibody that acts as an agonist of the Wingless-related integration site signaling pathway, which is in clinical development for the treatment of diabetic macular edema and neovascular age-related macular degeneration. The transaction was accounted for as an asset acquisition since MK-3000 accounted for substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $21 million, as well as a charge of $1.35 billion to Research and development expenses in 2024 related to the acquisition. Additionally, a $100 million developmental milestone was triggered and paid in 2024 upon initiation of a Phase 2/3 clinical trial
evaluating MK-3000 for the treatment of diabetic macular edema, which was also recorded as a charge to Research and development expenses.
Additionally in July 2024, Merck and Orion Corporation (Orion) announced the mutual exercise of an option to convert the companies’ ongoing co-development and co-commercialization agreement for opevesostat (MK-5684/ODM-208), an investigational cytochrome P450 11A1 (CYP11A1) inhibitor in Phase 3 clinical development, and other candidates targeting CYP11A1, into an exclusive global license for Merck. With the exercise of the option, Merck assumed full responsibility for all past and future development and commercialization expenses associated with the candidates covered by the original agreement entered into in 2022 as discussed below. In addition, Orion became eligible to receive developmental milestone payments of up to $30 million, regulatory milestone payments of up to $625 million and sales-based milestone payments of up to $975 million, as well as annually tiered royalties ranging from a low double-digit rate up to a rate in the low twenties on net sales for any commercialized licensed product. Orion retained responsibility for the manufacture of clinical and commercial supply for Merck. No payment was associated with the exercise of the option, which became effective in September 2024.
Also in July 2024, Merck notified Kelun-Biotech (a holding subsidiary of Sichuan Kelun Pharmaceutical Co., Ltd.) it was terminating the license and collaboration agreement entered into in July 2022 in which Merck gained exclusive worldwide rights for the development, manufacture and commercialization of an investigational antibody drug conjugate (ADC) MK-1200 (SKB315) for the treatment of solid tumors. As a result of this termination, which became effective in September 2024, all rights to SKB315 have reverted to Kelun-Biotech.
In March 2024, Merck acquired Harpoon Therapeutics, Inc. (Harpoon), a clinical-stage immunotherapy company developing a novel class of T-cell engagers designed to harness the power of the body’s immune system to treat patients suffering from cancer and other diseases for $765 million and also incurred $56 million of transaction costs. Harpoon’s lead candidate, MK-6070 (formerly HPN328), is a T-cell engager targeting delta-like ligand 3 (DLL3), an inhibitory canonical Notch ligand that is expressed at high levels in small-cell lung cancer and neuroendocrine tumors. The transaction was accounted for as an asset acquisition since MK-6070 represented substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $165 million, as well as a charge of $656 million to Research and development expenses in 2024 related to the transaction. There are no future contingent payments associated with the acquisition. In August 2024, Merck and Daiichi Sankyo expanded their existing global co-development and co-commercialization agreement to include MK-6070. See Note 4 for more information on Merck’s collaboration with Daiichi Sankyo.
2023 Transactions
In October 2023, Merck and Daiichi Sankyo entered into a global development and commercialization agreement for three of Daiichi Sankyo’s deruxtecan (DXd) ADC candidates: patritumab deruxtecan (HER3-DXd) (MK-1022), ifinatamab deruxtecan (I-DXd) (MK-2400) and raludotatug deruxtecan (R-DXd) (MK-5909). See Note 4 for additional information related to this collaboration.
In June 2023, Merck acquired Prometheus Biosciences, Inc. (Prometheus), a clinical-stage biotechnology company pioneering a precision medicine approach for the discovery, development, and commercialization of novel therapeutic and companion diagnostic products for the treatment of immune-mediated diseases. Total consideration paid of $11.0 billion included $1.2 billion of costs to settle share-based equity awards (including $700 million to settle unvested equity awards). Prometheus’ lead candidate, tulisokibart (MK-7240, formerly PRA023), is a humanized monoclonal antibody directed to tumor necrosis factor-like ligand 1A, a target associated with both intestinal inflammation and fibrosis. Tulisokibart is being developed for the treatment of immune-mediated diseases including ulcerative colitis, Crohn’s disease, and other autoimmune conditions. Phase 3 clinical trials evaluating tulisokibart for Crohn’s disease and ulcerative colitis are underway. The transaction was accounted for as an asset acquisition since tulisokibart accounted for substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $877 million, including cash of $368 million, investments of $296 million, deferred tax assets of $218 million and other net liabilities of $5 million, as well as a charge of $10.2 billion to Research and development expenses in 2023 related to the transaction. There are no future contingent payments associated with the acquisition.
In February 2023, Merck and Kelun-Biotech closed a license and collaboration agreement expanding their relationship in which Merck gained exclusive rights for the research, development, manufacture and commercialization of up to seven investigational preclinical ADCs for the treatment of cancer. Kelun-Biotech retained the right to research, develop, manufacture and commercialize certain licensed and option ADCs for Chinese mainland, Hong Kong and Macau. Merck made an upfront payment of $175 million, which was recorded as a charge to Research and development expenses in 2023. In October 2023, Merck notified Kelun-Biotech it was terminating two of the seven candidates under the agreement. Subsequently, in April 2024, Merck notified Kelun-Biotech it was terminating one additional candidate under the agreement. In July 2024, Merck notified Kelun-Biotech that it was
exercising an existing license option for one of the candidates under the agreement, granting Merck a license for the development, manufacture and commercialization worldwide excluding China. There are now three candidates licensed under the original agreement and one candidate for which the license option remains unexercised. Merck paid Kelun-Biotech $38 million in connection with the July option exercise, following which Kelun-Biotech remains eligible to receive future contingent payments aggregating up to $540 million in development-related payments, $1.5 billion in regulatory milestones, and $3.1 billion in sales-based milestones, if Kelun-Biotech does not retain Chinese mainland, Hong Kong and Macau rights for the remaining option ADC and all remaining candidates achieve regulatory approval. In addition, Kelun-Biotech is eligible to receive tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales for any commercialized ADC product. Also, in connection with the agreement, Merck invested $100 million in Kelun-Biotech shares in January 2023.
In January 2023, Merck acquired Imago BioSciences, Inc. (Imago), a clinical-stage biopharmaceutical company developing new medicines for the treatment of myeloproliferative neoplasms and other bone marrow diseases, for $1.35 billion (including payments to settle share-based equity awards) and also incurred approximately $60 million of transaction costs. Imago’s lead candidate, bomedemstat (MK-3543, formerly IMG-7289), which is in Phase 3 clinical development, is an investigational orally available lysine-specific demethylase 1 inhibitor currently being evaluated in multiple clinical trials for the treatment of essential thrombocythemia, myelofibrosis, and polycythemia vera, in addition to other indications. The transaction was accounted for as an asset acquisition since bomedemstat represented substantially all of the fair value of the gross assets acquired (excluding cash and deferred income taxes). Merck recorded net assets of $219 million, as well as a charge of $1.2 billion to Research and development expenses in 2023 related to the transaction. There are no future contingent payments associated with the acquisition.
2022 Transactions
In October 2022, Merck and Royalty Pharma plc (Royalty Pharma) entered into a funding arrangement under which Royalty Pharma paid Merck $50 million to co-fund Merck’s development costs for a Phase 2b trial of MK-8189, an investigational oral phosphodiesterase 10A (PDE10A) inhibitor, which was being evaluated for the treatment of schizophrenia. As Royalty Pharma was sharing the risk of technical and regulatory success with Merck, the development funding was recognized by Merck as an obligation to perform contractual services. Accordingly, the payment received was recognized by Merck as a reduction to Research and development expenses ratably over the estimated Phase 2b research period. In 2024, it was determined the Phase 2b clinical trial for MK-8189 as a monotherapy for acute schizophrenia did not meet its primary efficacy endpoint; therefore, further development in schizophrenia, bipolar, and dementia indications has stopped, and the funding arrangement was terminated.
In September 2022, Merck exercised its option to jointly develop and commercialize V940 (mRNA-4157), an investigational individualized neoantigen therapy, pursuant to the terms of an existing collaboration and license agreement with Moderna, Inc. (Moderna). See Note 4 for additional information related to this collaboration.
In August 2022, Merck and Orna Therapeutics (Orna), a biotechnology company pioneering a new investigational class of engineered circular RNA (oRNA) therapies, entered into a collaboration agreement to discover, develop, and commercialize multiple programs, including vaccines and therapeutics in the areas of infectious disease and oncology. Under the terms of the agreement, Merck made an upfront payment to Orna of $150 million, which was recorded as a charge to Research and development expenses in 2022. In addition, Orna is eligible to receive future contingent payments aggregating up to $440 million in development-related payments, $675 million in regulatory milestones, and $2.4 billion in sales-based milestones associated with the progress of the multiple vaccine and therapeutic programs, as well as royalties ranging from a high-single-digit rate to a low-double-digit rate on any approved products derived from the collaboration. Merck also invested $100 million in Orna’s Series B preferred shares in 2022.
In July 2022, Merck and Orion Corporation (Orion) announced a global co-development and co-commercialization agreement for Orion’s investigational candidate opevesostat (MK-5684/ODM-208) and other drugs targeting cytochrome P450 11A1 (CYP11A1), an enzyme important in steroid production. Merck made an upfront payment to Orion of $290 million, which was recorded as a charge to Research and development expenses in 2022. Orion is responsible for the manufacture of clinical and commercial supply of opevesostat. In addition, the contract provided both parties with an option to convert the initial co-development and co-commercialization agreement into a global exclusive license to Merck, which was mutually exercised in July 2024 (as noted above).
In May 2022, in connection with an existing arrangement, Merck exercised its option to obtain an exclusive license outside of Chinese mainland, Hong Kong, Macau and Taiwan for the development, manufacture and commercialization of Kelun-Biotech’s trophoblast antigen 2 (TROP2)-targeting ADC programs, including its lead compound, sacituzumab tirumotecan (MK-2870/SKB-264), which is currently in Phase 3 clinical development. Under the terms of the agreement, Merck and Kelun-Biotech are collaborating on certain early clinical development plans,
including evaluating the potential of sacituzumab tirumotecan as a monotherapy and in combination with Keytruda for advanced solid tumors. Upon option exercise, Merck made a payment of $30 million, which was recorded as a charge to Research and development expenses in 2022. Additionally, Merck made an additional payment of $25 million upon technology transfer in 2023. Merck has also made all contingent developmental milestone payments under the agreement, which aggregated $90 million, nearly all of which were paid in 2024 and were recorded to Research and development expenses. In addition, Kelun-Biotech is eligible to receive future contingent milestone payments (which include all program compounds) aggregating up to $290 million in first commercial sale milestones, and $780 million in sales-based milestones. The agreement also provides for Merck to pay tiered royalties ranging from a mid-single-digit rate to a low-double-digit rate on future net sales.
Spin-Off of Organon & Co.
In connection with the 2021 spin-off of Organon & Co. (Organon), Merck and Organon entered into a series of interim operating agreements pursuant to which in various jurisdictions where Merck held licenses, permits and other rights in connection with marketing, import and/or distribution of Organon products prior to the separation, Merck continued to market, import and distribute such products on behalf of Organon until such time as the relevant licenses and permits transferred to Organon, with Organon receiving all of the economic benefits and burdens of such activities. As of December 31, 2024, only one jurisdiction remains under an interim operating agreement. Additionally, Merck and Organon entered into a number of manufacturing and supply agreements (MSAs) with terms ranging from four years to ten years. The amounts included in the consolidated statement of income for the above MSAs include sales of $392 million, $394 million and $383 million in 2024, 2023 and 2022, respectively, and related cost of sales of $390 million, $422 million and $404 million in 2024, 2023 and 2022, respectively. The amounts due from Organon under all spin-off related agreements were $330 million and $632 million at December 31, 2024 and 2023, respectively, and are reflected in Other current assets. The amounts due to Organon under these agreements were $113 million and $598 million at December 31, 2024 and 2023, respectively, and are included in Accrued and other current liabilities.
v3.25.0.1
Collaborative Arrangements
12 Months Ended
Dec. 31, 2024
Collaborative Arrangements [Abstract]  
Collaborative Arrangements Collaborative Arrangements
Merck has entered into collaborative arrangements that provide the Company with varying rights to develop, produce and market products together with its collaborative partners. Both parties in these arrangements are active participants and exposed to significant risks and rewards dependent on the commercial success of the activities of the collaboration. Merck’s more significant collaborative arrangements are discussed below.
AstraZeneca PLC
In 2017, Merck and AstraZeneca PLC (AstraZeneca) entered into a global strategic oncology collaboration to co-develop and co-commercialize AstraZeneca’s Lynparza (olaparib) for multiple cancer types. Independently, Merck and AstraZeneca are developing and commercializing Lynparza in combinations with their respective PD-1 and PD-L1 medicines, Keytruda and Imfinzi. The companies are also jointly developing and commercializing AstraZeneca’s Koselugo (selumetinib) for multiple indications. Under the terms of the agreement, AstraZeneca and Merck share the development and commercialization costs for Lynparza and Koselugo monotherapy and non-PD-1/PD-L1 combination therapy opportunities.
Profits from Lynparza and Koselugo product sales generated through monotherapies or combination therapies are shared equally. AstraZeneca is the principal on Lynparza and Koselugo sales transactions. Merck records its share of Lynparza and Koselugo product sales, net of cost of sales and commercialization costs, as alliance revenue, and its share of development costs associated with the collaboration as part of Research and development expenses. Reimbursements received from AstraZeneca for research and development expenses are recognized as reductions to Research and development costs.
As part of the agreement, Merck made an upfront payment to AstraZeneca and also made payments over a multi-year period for certain license options. In addition, the agreement provides for contingent payments from Merck to AstraZeneca related to the successful achievement of sales-based and regulatory milestones.
In 2024, sales of Koselugo triggered a $100 million sales-based milestone payment from Merck to AstraZeneca. Accordingly, Merck recorded a $100 million liability (which remained accrued at December 31, 2024 and was subsequently paid in January 2025) and a corresponding increase to the intangible asset related to Koselugo. Merck also recognized $48 million of cumulative amortization catch-up expense related to the recognition of this milestone in 2024. Merck made a sales-based milestone payment to AstraZeneca of $400 million in 2022 (which had been previously accrued for). Additionally, in 2022, Merck determined it was probable that sales of Lynparza in the future would trigger a $600 million sales-based milestone payment from Merck to AstraZeneca. Accordingly, Merck recorded a $600 million liability (which remained accrued at December 31, 2024 and was
subsequently paid in January 2025) and a corresponding increase to the intangible asset related to Lynparza. Merck also recognized $250 million of cumulative amortization catch-up expense related to the recognition of this milestone in 2022. Potential future sales-based milestone payments of $2.0 billion have not yet been accrued as they are not deemed by the Company to be probable at this time.
Lynparza received regulatory approvals triggering capitalized milestone payments from Merck to AstraZeneca of $245 million, $105 million and $250 million in 2024, 2023 and 2022, respectively (each of which had been previously accrued for). In 2024, the partners agreed that no future regulatory milestone payments from Merck to AstraZeneca are likely under the agreement.
The intangible asset balances related to Lynparza (which includes capitalized sales-based and regulatory milestone payments) and Koselugo (which reflects the 2024 capitalized sales-based milestone payment) were $1.2 billion and $49 million, respectively, at December 31, 2024 and are included in Other Intangibles, Net. The assets are being amortized over their estimated useful lives (through 2028 for Lynparza and through 2029 for Koselugo) as supported by projected future cash flows, subject to impairment testing.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Lynparza$1,311 $1,199 $1,116 
Alliance revenue - Koselugo170 97 54 
Total alliance revenue$1,481 $1,296 $1,170 
Cost of sales (1)
378 311 492 
Selling, general and administrative165 192 185 
Research and development77 79 106 
December 3120242023
Receivables from AstraZeneca included in Other current assets
$424 $341 
Payables to AstraZeneca included in Accrued and other current liabilities (2)
713 256 
Payables to AstraZeneca included in Other Noncurrent Liabilities (2)
 600 
(1)    Represents amortization of capitalized milestone payments. Amounts in 2024 and 2022 include $48 million and $250 million, respectively, of cumulative amortization catch-up expense as noted above.
(2)    Includes accrued milestone payments.
Eisai Co., Ltd.
In 2018, Merck and Eisai Co., Ltd. (Eisai) announced a strategic collaboration for the worldwide co-development and co-commercialization of Lenvima (lenvatinib), an orally available tyrosine kinase inhibitor discovered by Eisai. Under the agreement, Merck and Eisai are developing and commercializing Lenvima jointly, both as monotherapy and in combination with Keytruda. Eisai records Lenvima product sales globally (Eisai is the principal on Lenvima sales transactions) and Merck and Eisai share applicable profits equally. Merck records its share of Lenvima product sales, net of cost of sales and commercialization costs, as alliance revenue. Expenses incurred during co-development are shared by the two companies in accordance with the collaboration agreement and reflected in Research and development expenses. Certain expenses incurred solely by Merck or Eisai are not shareable under the collaboration agreement, including costs incurred in excess of agreed upon caps and costs related to certain combination studies of Keytruda and Lenvima.
Under the agreement, Merck made an upfront payment to Eisai and also made payments over a multi-year period for certain option rights. In addition, the agreement provides for contingent payments from Merck to Eisai related to the successful achievement of sales-based and regulatory milestones.
Merck made sales-based milestone payments to Eisai aggregating $125 million, $125 million and $600 million in 2024, 2023 and 2022, respectively. In 2023, Merck determined it was probable that sales of Lenvima in the future would trigger $250 million of sales-based milestone payments from Merck to Eisai. Accordingly, Merck recorded $250 million of liabilities (of which $125 million was subsequently paid in each of 2024 and 2023 as noted above) and corresponding increases to the intangible asset related to Lenvima. Merck also recognized $154 million of cumulative amortization catch-up expense related to the recognition of these milestones in 2023. Potential future sales-based milestone payments of $2.3 billion have not yet been accrued as they are not deemed by the Company to be probable at this time.
In 2022, Lenvima received regulatory approvals triggering capitalized milestone payments of $50 million from Merck to Eisai. There are no regulatory milestone payments remaining under the agreement.
The intangible asset balance related to Lenvima (which includes capitalized sales-based and regulatory milestone payments) was $442 million at December 31, 2024 and is included in Other Intangibles, Net. The amount is being amortized over its estimated useful life through 2026 as supported by projected future cash flows, subject to impairment testing.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Lenvima$1,010 $960 $876 
Cost of sales (1)
241 381 212 
Selling, general and administrative159 189 158 
Research and development21 66 136 
December 3120242023
Receivables from Eisai included in Other current assets
$257 $226 
Payables to Eisai included in Accrued and other current liabilities (2)
 125 
(1)     Represents amortization of capitalized milestone payments. Amount in 2023 includes $154 million of cumulative amortization catch-up expense as noted above.
(2)     Represents an accrued milestone payment.
Bayer AG
In 2014, the Company entered into a worldwide clinical development collaboration with Bayer AG (Bayer) to market and develop soluble guanylate cyclase (sGC) modulators including Bayer’s Adempas (riociguat) and Verquvo (vericiguat). The two companies have implemented a joint development and commercialization strategy. Under the agreement, Bayer commercializes Adempas in the Americas, while Merck commercializes in the rest of the world. For Verquvo, Merck commercializes in the U.S. and Bayer commercializes in the rest of the world. Both companies share in development costs and profits on sales. Merck records sales of Adempas and Verquvo in its marketing territories, as well as alliance revenue. Alliance revenue represents Merck’s share of profits from sales of Adempas and Verquvo in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs. Cost of sales includes Bayer’s share of profits from sales in Merck’s marketing territories.
In addition, the agreement provided for contingent payments from Merck to Bayer related to the successful achievement of sales-based milestones. In 2022, Merck made the final $400 million sales-based milestone payment under this collaboration to Bayer.
The intangible asset balances related to Adempas (which includes the acquired intangible asset balance, as well as capitalized sales-based milestone payments attributed to Adempas) and Verquvo (which reflects the portion of the final sales-based milestone payment that was attributed to Verquvo) were $372 million and $42 million, respectively, at December 31, 2024 and are included in Other Intangibles, Net. The assets are being amortized over their estimated useful lives (through 2027 for Adempas and through 2031 for Verquvo) as supported by projected future cash flows, subject to impairment testing.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Adempas/Verquvo$415 $367 $341 
Net sales of Adempas recorded by Merck287 255 238 
Net sales of Verquvo recorded by Merck37 36 22 
Total sales$739 $658 $601 
Cost of sales (1)
244 224 210 
Selling, general and administrative111 131 153 
Research and development102 90 75 
December 3120242023
Receivables from Bayer included in Other current assets
$160 $156 
Payables to Bayer included in Accrued and other current liabilities
82 80 
(1)    Includes amortization of intangible assets, cost of products sold by Merck, as well as Bayer’s share of profits from sales in Merck’s marketing territories.
Ridgeback Biotherapeutics LP
In 2020, Merck and Ridgeback Biotherapeutics LP (Ridgeback), a closely held biotechnology company, entered into a collaboration agreement to develop Lagevrio (molnupiravir), an investigational orally available antiviral candidate for the treatment of patients with COVID-19. Merck gained exclusive worldwide rights to develop and commercialize Lagevrio and related molecules. Following initial authorizations in certain markets in 2021, Lagevrio has since received multiple additional authorizations.
Under the terms of the agreement, Ridgeback received an upfront payment and is eligible to receive future contingent payments dependent upon the achievement of certain developmental and regulatory approval milestones. The agreement also provides for Merck to reimburse Ridgeback for a portion of certain third-party contingent milestone payments and royalties on net sales, which is part of the profit-sharing calculation. Merck is the principal on sales transactions, recognizing sales and related costs, with profit-sharing amounts recorded within Cost of sales. Profits from the collaboration are split equally between the partners. Reimbursements from Ridgeback for its share of research and development costs (deducted from Ridgeback’s share of profits) are reflected as decreases to Research and development expenses.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Net sales of Lagevrio recorded by Merck
$964 $1,428 $5,684 
Cost of sales (1)
554 852 3,038 
Selling, general and administrative
57 97 147 
Research and development
13 60 88 
December 3120242023
Payables to Ridgeback included in Accrued and other current liabilities (2)
$68 $113 
(1)    Includes cost of products sold by Merck, Ridgeback’s share of profits, royalty expense, amortization of capitalized milestone payments and inventory reserves.
(2)    Includes accrued royalties.
Daiichi Sankyo
In October 2023, Merck and Daiichi Sankyo entered into a global development and commercialization agreement for three of Daiichi Sankyo’s DXd ADC candidates: patritumab deruxtecan (HER3-DXd) (MK-1022), ifinatamab deruxtecan (I-DXd) (MK-2400) and raludotatug deruxtecan (R-DXd) (MK-5909). All three potentially first-in-class DXd ADCs are in various stages of clinical development for the treatment of multiple solid tumors both as monotherapy and/or in combination with other treatments. The companies will jointly develop and potentially commercialize these ADC candidates worldwide, except in Japan where Daiichi Sankyo will maintain exclusive rights. Daiichi Sankyo will be solely responsible for manufacturing and supply.
Under the terms of the agreement, Merck made payments to Daiichi Sankyo totaling $4.0 billion in 2023. These payments included $1.0 billion ($500 million each for patritumab deruxtecan and ifinatamab deruxtecan) which may be refundable on a pro-rated basis in the event of early termination of development with respect to either program. In addition, the agreement provided for a continuation payment of $750 million related to patritumab deruxtecan, which Merck paid in October 2024, and a continuation payment of $750 million related to raludotatug deruxtecan due from Merck in October 2025. If Merck does not make the remaining continuation payment for raludotatug deruxtecan, the rights for that program will revert to Daiichi Sankyo and the non-refundable upfront payments already paid will be retained by Daiichi Sankyo. The agreement also provides for contingent payments from Merck to Daiichi Sankyo of up to an additional $5.5 billion for each DXd ADC upon the successful achievement of certain sales-based milestones.
In conjunction with this transaction, Merck recorded an aggregate pretax charge of $5.5 billion to Research and development expenses in 2023 for the $4.0 billion of upfront payments and the $1.5 billion of continuation payments. Merck determined it was appropriate to expense the $1.0 billion refundable portion of the consideration in 2023 because of the significant number of clinical studies that were underway and planned in the near future, as well as certain studies in advanced stages, making it highly likely that the programs would continue to progress and incur substantial expenses, and therefore the likelihood of the programs terminating before the end of the refundable period was deemed remote. Merck also determined that it was appropriate to expense the continuation payments upon execution of the agreement because such payments do not result in the Company gaining any additional intellectual property rights. In addition, the significant number of ongoing and planned clinical studies and the short-term nature of the option period makes the likelihood of Merck not making these payments remote.
Merck and Daiichi Sankyo equally share research and development costs, except for raludotatug deruxtecan, where Merck is responsible for 75% of the first $2.0 billion of research and development expenses. Merck includes its share of development costs associated with the collaboration as part of Research and development expenses. Following regulatory approval, Daiichi Sankyo will generally record sales worldwide (Daiichi Sankyo will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide except for Japan where Daiichi Sankyo retains exclusive rights and Merck will receive a 5% sales-based royalty. Merck will record its share of product sales, net of cost of sales and commercialization costs, as alliance revenue.
In August 2024, Merck and Daiichi Sankyo expanded their agreement to include MK-6070, an investigational delta-like ligand 3 (DLL3) targeting T-cell engager, which Merck obtained through its acquisition of Harpoon (see Note 3). The companies are planning to evaluate MK-6070 in combination with ifinatamab deruxtecan in certain patients with SCLC, as well as other potential combinations. Merck received an upfront cash payment of $170 million from Daiichi Sankyo (recorded within Other (income) expense, net) and has also satisfied a contingent quid obligation from the original collaboration agreement. The companies will jointly develop and commercialize MK-6070 worldwide and share research and development and commercialization expenses. Research and development expenses related to MK-6070 in combination with ifinatamab deruxtecan will be shared in a manner consistent with the original agreement for ifinatamab deruxtecan. Merck will be solely responsible for manufacturing and supply of MK-6070. If approved, Merck will generally record sales for MK-6070 worldwide (Merck will be the principal on sales transactions) and the companies will equally share expenses as well as profits worldwide, except for Japan where Merck retains exclusive rights and Daiichi Sankyo will receive a 5% sales-based royalty.
Summarized financial information related to this collaboration is as follows:
Years Ended December 3120242023
Selling, general and administrative
$26 $
Research and development (1)
351 5,549 
December 3120242023
Receivables from Daiichi Sankyo included in Other current assets
$8 $— 
Payables to Daiichi Sankyo included in Accrued and other current liabilities (2)
817 800 
Payables to Daiichi Sankyo included in Other Noncurrent Liabilities (2)
 750 
(1)    Expenses in 2023 include the $5.5 billion charge for the upfront and continuing option payments noted above.
(2)    Includes accrued continuation payment.
Moderna, Inc.
In 2022, Merck exercised its option to jointly develop and commercialize V940 (mRNA-4157), an investigational individualized neoantigen therapy, pursuant to the terms of an existing collaboration and license agreement with Moderna, Inc. (Moderna), which resulted in a $250 million payment that was charged to Research and development expenses in 2022. V940 (mRNA-4157) is currently being evaluated in combination with Keytruda in multiple Phase 3 clinical trials. Merck and Moderna share costs and will share any profits equally under this worldwide collaboration. Merck records its share of development costs associated with the collaboration as part of Research and development expenses. Any reimbursements received from Moderna for research and development expenses are recognized as reductions to Research and development costs. Merck has also capitalized certain of the shared costs, mainly related to facility costs, which aggregated $198 million at December 31, 2024 and will be amortized over the assets’ estimated useful lives.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Selling, general and administrative
$16 $$— 
Research and development (1)
358 218 288 
December 3120242023
Payables to Moderna included in Accrued and other current liabilities
$57 $63 
(1)    Expenses in 2022 include the $250 million option exercise payment noted above.
Bristol-Myers Squibb Company
Reblozyl (luspatercept-aamt) is a first-in-class erythroid maturation recombinant fusion protein that is being commercialized through a global collaboration with Bristol-Myers Squibb Company (BMS). Reblozyl is approved in the U.S., Europe, and certain other markets for the treatment of anemia in certain rare blood disorders and is also being evaluated for additional indications for hematology therapies. BMS is the principal on sales transactions for Reblozyl; however, Merck co-promotes Reblozyl (and may co-promote any future products approved under this collaboration) in North America, which is reimbursed by BMS. Merck receives tiered royalties ranging from 20% to 24% based on sales levels. This royalty will be reduced by 50% upon the earlier of patent expiry or generic entry on an indication-by-indication basis in each market. Additionally, Merck is eligible to receive future contingent sales-based milestone payments of up to $80 million. Alliance revenue related to this collaboration (recorded within Sales) consists of royalties and, for 2022, also includes the receipt of a regulatory approval milestone payment of $20 million. Merck recorded alliance revenue related to this collaboration of $371 million in 2024, $212 million in 2023 and $166 million in 2022.
v3.25.0.1
Restructuring
12 Months Ended
Dec. 31, 2024
Restructuring and Related Activities [Abstract]  
Restructuring Restructuring
In January 2024, the Company approved a new restructuring program (2024 Restructuring Program) intended to continue the optimization of the Company’s Human Health global manufacturing network as the future pipeline shifts to new modalities and also optimize the Animal Health global manufacturing network to improve supply reliability and increase efficiency. The actions contemplated under the 2024 Restructuring Program are expected to be substantially completed by the end of 2031, with the cumulative pretax costs to be incurred by the Company to implement the program estimated to be approximately $4.0 billion. Approximately 60% of the cumulative pretax costs will be non-cash, relating primarily to the accelerated depreciation of facilities to be closed or divested. The remainder of the costs will result in cash outlays, relating primarily to facility shut-down costs. The Company recorded total pretax costs of $888 million and $190 million in 2024 and 2023, respectively, related to the 2024 Restructuring Program, bringing total cumulative pretax costs incurred through December 31, 2024 to $1.1 billion.
In 2019, Merck approved a global restructuring program (2019 Restructuring Program) as part of a worldwide initiative focused on optimizing the Company’s manufacturing and supply network, as well as reducing its global real estate footprint. The Company recorded total pretax costs of $743 million in 2023 and $666 million in 2022 related to the 2019 Restructuring Program. The actions under the 2019 Restructuring Program were substantially complete at the end of 2023 and, as of January 1, 2024, any remaining activities are being accounted for as part of the 2024 Restructuring Program.
For segment reporting, restructuring charges are unallocated expenses.
The following table summarizes the charges related to the restructuring programs by type of cost:
Accelerated
Depreciation
Separation
Costs
Other Exit Costs
Total
Year Ended December 31, 2024
2024 Restructuring Program
Cost of sales$254 $ $241 $495 
Selling, general and administrative  83 83 
Research and development  1 1 
Restructuring costs 122 187 309 
$254 $122 $512 $888 
Year Ended December 31, 2023
2024 Restructuring Program
Cost of sales$— $— $62 $62 
Restructuring costs— 115 13 128 
— 115 75 190 
2019 Restructuring Program
Cost of sales131 — 18 149 
Selling, general and administrative— 113 122 
Research and development— — 
Restructuring costs— 339 132 471 
 140 339 264 743 
$140 $454 $339 $933 
Year Ended December 31, 2022    
2019 Restructuring Program
Cost of sales$72 $— $133 $205 
Selling, general and administrative19 — 75 94 
Research and development29 — 30 
Restructuring costs— 212 125 337 
 $120 $212 $334 $666 
Accelerated depreciation costs primarily relate to manufacturing, research and administrative facilities and equipment to be sold or closed as part of the programs. Accelerated depreciation costs represent the difference between the depreciation expense to be recognized over the revised useful life of the asset, based upon the anticipated date the site will be closed or divested or the equipment disposed of, and depreciation expense as determined utilizing the useful life prior to the restructuring actions. All the sites will continue to operate up through the respective closure dates and, since future undiscounted cash flows are sufficient to recover the respective book values, Merck is recording accelerated depreciation over the revised useful life of the site assets. Anticipated site closure dates, particularly related to manufacturing locations, have been and may continue to be adjusted to reflect changes resulting from regulatory or other factors.
Separation costs are associated with actual headcount reductions, as well as involuntary headcount reductions which were probable and could be reasonably estimated.
Other exit costs in 2024, 2023 and 2022 include asset impairment, facility shut-down and other related costs, as well as pretax gains and losses resulting from the sales of facilities and related assets. Additionally, other activity includes certain employee-related costs associated with pension and other postretirement benefit plans (see Note 13) and share-based compensation.
The following table summarizes the charges and spending relating to restructuring program activities:
Accelerated
Depreciation
Separation
Costs
Other Exit Costs
Total
Restructuring reserves January 1, 2023
$— $479 $34 $513 
Expenses140 454 339 933 
(Payments) receipts, net— (252)(158)(410)
Non-cash activity(140)— (184)(324)
Restructuring reserves December 31, 2023
— 681 31 712 
Expenses254 122 512 888 
(Payments) receipts, net (239)(206)(445)
Non-cash activity(254) (337)(591)
Restructuring reserves December 31, 2024
$ $564 $ $564 
v3.25.0.1
Financial Instruments
12 Months Ended
Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Financial Instruments Financial Instruments
Derivative Instruments and Hedging Activities
The Company manages the impact of foreign exchange rate movements and interest rate movements on its earnings, cash flows and fair values of assets and liabilities through operational means and through the use of various financial instruments, including derivative instruments.
A significant portion of the Company’s revenues and earnings in foreign affiliates is exposed to changes in foreign exchange rates. The objectives of and accounting related to the Company’s foreign currency risk management program, as well as its interest rate risk management activities are discussed below.

Foreign Currency Risk Management
The Company has established revenue hedging, balance sheet risk management and net investment hedging programs to protect against volatility of future foreign currency cash flows and changes in fair value caused by changes in foreign exchange rates.
The objective of the revenue hedging program is to reduce the variability caused by changes in foreign exchange rates that would affect the U.S. dollar value of future cash flows derived from foreign currency denominated sales, primarily the euro, Japanese yen and Chinese renminbi. To achieve this objective, the Company will hedge a portion of its forecasted foreign currency denominated third-party and intercompany distributor entity sales (forecasted sales) that are expected to occur over its planning cycle, typically no more than two years into the future. The Company will layer in hedges over time, increasing the portion of forecasted sales hedged as it gets closer to the expected date of the forecasted sales. The portion of forecasted sales hedged is based on assessments of cost-benefit profiles that consider natural offsetting exposures, revenue and foreign exchange rate volatilities and correlations, and the cost of hedging instruments. The Company manages its anticipated transaction exposure principally with purchased local currency put options, forward contracts, and purchased collar options.
The fair values of these derivative contracts are recorded as either assets (gain positions) or liabilities (loss positions) in the Consolidated Balance Sheet. Changes in the fair value of derivative contracts are recorded each period in either current earnings or OCI depending on whether the derivative is designated as part of a hedge transaction and, if so, the type of hedge transaction. For derivatives that are designated as cash flow hedges, the unrealized gains or losses on these contracts are recorded in AOCL and reclassified into Sales when the hedged anticipated revenue is recognized. The amount reclassified into earnings as a result of the discontinuation of cash flow hedges because it was no longer deemed probable the forecasted hedged transactions would occur was not material for the years ended December 31, 2024, 2023 or 2022. For those derivatives which are not designated as cash flow hedges, but serve as economic hedges of forecasted sales, unrealized gains or losses are recorded in Sales each period. The cash flows from both designated and non-designated contracts are reported as operating activities in the Consolidated Statement of Cash Flows. The Company does not enter into derivatives for trading or speculative purposes.
The Company manages operating activities and net asset positions at each local subsidiary in order to mitigate the effects of foreign exchange on monetary assets and liabilities. Monetary assets and liabilities denominated in a currency other than the functional currency of a given subsidiary are remeasured at spot rates in effect on the balance sheet date with the effects of changes in spot rates reported in Other (income) expense, net. The Company also uses a balance sheet risk management program to mitigate the exposure of such assets and liabilities from the effects of volatility in foreign exchange. Merck principally utilizes forward exchange contracts to
offset the effects of foreign exchange on exposures when it is deemed economical to do so based on a cost-benefit analysis that considers the magnitude of the exposure, the volatility of the foreign exchange rate and the cost of the hedging instrument (primarily the euro, Swiss franc, Japanese yen, and Chinese renminbi). The forward contracts are not designated as hedges and are marked to market through Other (income) expense, net. Accordingly, fair value changes in the forward contracts help mitigate the changes in the value of the remeasured assets and liabilities attributable to changes in foreign currency exchange rates, except to the extent of the spot-forward differences. These differences are not significant due to the short-term nature of the contracts, which typically have average maturities at inception of less than six months. The cash flows from these contracts are reported as operating activities in the Consolidated Statement of Cash Flows.
The Company also uses forward exchange contracts to hedge a portion of its net investment in foreign operations against movements in foreign exchange rates. The forward contracts are designated as hedges of the net investment in a foreign operation. The unrealized gains or losses on these contracts are recorded in foreign currency translation adjustment within OCI, and remain in AOCL until either the sale or complete or substantially complete liquidation of the subsidiary. The Company excludes certain portions of the change in fair value of its derivative instruments from the assessment of hedge effectiveness (excluded components). Changes in fair value of the excluded components are recognized in OCI. The Company recognizes in earnings the initial value of the excluded components on a straight-line basis over the life of the derivative instrument, rather than using the mark-to-market approach. The cash flows from these contracts are reported as investing activities in the Consolidated Statement of Cash Flows.
Foreign exchange risk is also managed through the use of foreign currency debt. Certain of the Company’s senior unsecured euro-denominated notes have been designated as, and are effective as, economic hedges of the net investment in a foreign operation. Accordingly, foreign currency transaction gains or losses due to spot rate fluctuations on the euro-denominated debt instruments are included in foreign currency translation adjustment within OCI.
The effects of the Company’s net investment hedges on OCI and the Consolidated Statement of Income are shown below:
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (1)
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing
Years Ended December 31202420232022202420232022
Net Investment Hedging Relationships
Foreign exchange contracts$(30)$— $(48)$(4)$$(1)
Euro-denominated notes(192)105 (162) — — 
(1)    No amounts were reclassified from AOCL into income related to the sale of a subsidiary.

Interest Rate Risk Management
The Company may use interest rate swap contracts on certain investing and borrowing transactions to manage its net exposure to interest rate changes and to reduce its overall cost of borrowing. The Company does not use leveraged swaps and, in general, does not leverage any of its investment activities that would put principal at risk.
At December 31, 2024, the Company was a party to six pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of the fixed-rate notes as detailed in the table below.
Par Value of DebtNumber of Interest Rate Swaps HeldTotal Swap Notional Amount
4.50% notes due 2033
$1,500 $1,500 
The interest rate swap contracts are designated hedges of the fair value changes in the notes attributable to changes in the benchmark Secured Overnight Financing Rate (SOFR) swap rate. The fair value changes in the notes attributable to changes in the SOFR swap rate are recorded in interest expense along with the offsetting fair value changes in the swap contracts. In January 2025, the Company entered into an additional interest rate swap contract with a notional amount of $250 million related to its 5.00% notes due 2053. The cash flows from these contracts are reported as operating activities in the Consolidated Statement of Cash Flows.
The table below presents the location of amounts recorded in the Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges as of December 31:
Carrying Amount of Hedged Liabilities
Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount
2024202320242023
Balance Sheet Caption
Long-Term Debt $1,509 $1,056 $17 $56 
Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments as of December 31:
  20242023
  Fair Value of
Derivative
U.S. Dollar
Notional
Fair Value of
Derivative
U.S. Dollar
Notional
 AssetLiabilityAssetLiability
Derivatives Designated as Hedging InstrumentsBalance Sheet Caption      
Interest rate swap contracts
Other Assets
$17 $ $1,500 $57 $— $1,000 
Foreign exchange contractsOther current assets323  8,662 106 — 6,138 
Foreign exchange contractsOther Assets66  2,125 26 — 1,929 
Foreign exchange contractsAccrued and other current liabilities 1 162 — 76 3,680 
Foreign exchange contractsOther Noncurrent Liabilities 1 16 — 
  $406 $2 $12,465 $189 $77 $12,754 
Derivatives Not Designated as Hedging InstrumentsBalance Sheet Caption      
Foreign exchange contractsOther current assets$323 $ $12,544 $153 $— $9,693 
Foreign exchange contractsAccrued and other current liabilities 343 13,551 — 162 8,104 
  $323 $343 $26,095 $153 $162 $17,797 
  $729 $345 $38,560 $342 $239 $30,551 
As noted above, the Company records its derivatives on a gross basis in the Consolidated Balance Sheet. The Company has master netting agreements with several of its financial institution counterparties (see Concentrations of Credit Risk below). The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes as of December 31:
20242023
AssetLiabilityAssetLiability
Gross amounts recognized in the consolidated balance sheet$729 $345 $342 $239 
Gross amounts subject to offset in master netting arrangements not offset in the consolidated balance sheet(299)(299)(215)(215)
Cash collateral received
(165) (3)— 
Net amounts$265 $46 $124 $24 
The table below provides information regarding the location and amount of pretax gains and losses of derivatives designated in fair value or cash flow hedging relationships:
Years Ended December 31202420232022202420232022202420232022
Financial Statement Caption in which Effects of Fair Value or Cash Flow Hedges are RecordedSales
Other (income) expense, net (1)
Other comprehensive income (loss)
$64,168 $60,115 $59,283 $(24)$466 $1,501 $216 $(393)$(339)
(Gain) loss on fair value hedging relationships:
Interest rate swap contracts
Hedged items — — (39)56 (13) — — 
Derivatives designated as hedging instruments — — 39 (57) — — 
Impact of cash flow hedging relationships:
Foreign exchange contracts
Amount of gain recognized in OCI on derivatives
 — —  — — 508 114 684 
Increase in Sales as a result of AOCL reclassifications
167 249 773  — — (167)(249)(773)
Interest rate contracts
Amount of gain recognized in Other (income) expense, net on derivatives
 — — (1)(1)(2) — — 
Amount of (loss) gain recognized in OCI on derivatives
 — —  — — (1)13 (2)
(1)    Interest expense is a component of Other (income) expense, net.
The table below provides information regarding the income statement effects of derivatives not designated as hedging instruments:
Amount of Derivative Pretax Loss (Gain) Recognized in Income
Years Ended December 31202420232022
Derivatives Not Designated as Hedging InstrumentsIncome Statement Caption
Foreign exchange contracts (1)
Other (income) expense, net$251 $(6)$(49)
Foreign exchange contracts (2)
Sales(28)(37)
(1)    These derivative contracts primarily mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.
(2)     These derivative contracts serve as economic hedges of forecasted transactions.
At December 31, 2024, the Company estimates $262 million of pretax net unrealized gains on derivatives maturing within the next 12 months that hedge foreign currency denominated sales over that same period will be reclassified from AOCL to Sales. The amount ultimately reclassified to Sales may differ as foreign exchange rates change. Realized gains and losses are ultimately determined by actual foreign exchange rates at maturity.
Investments in Debt and Equity Securities
Information on investments in debt and equity securities at December 31 is as follows:
 
 20242023
 Amortized
Cost
Gross UnrealizedFair
Value
Amortized
Cost
Gross UnrealizedFair
Value
GainsLossesGainsLosses
Commercial paper$348 $ $ $348 $252 $— $— $252 
U.S. government and agency securities188   188 72— — 72 
Corporate notes and bonds    13 — — 13 
Total debt securities$536 $ $ $536 $337 $— $— $337 
Publicly traded equity securities (1)
920 764 
Total debt and publicly traded equity securities$1,456 $1,101 
(1)    Unrealized net losses of $30 million were recorded in Other (income) expense, net in 2024 on equity securities still held at December 31, 2024. Unrealized net gains of $411 million were recorded in Other (income) expense, net in 2023 on equity securities still held at December 31, 2023.
At December 31, 2024 and 2023, the Company also had $863 million and $832 million, respectively, of equity investments without readily determinable fair values included in Other Assets. The Company records unrealized gains on these equity investments based on favorable observable price changes from transactions involving similar investments of the same investee and records unrealized losses based on unfavorable observable price changes, which are included in Other (income) expense, net. During 2024, the Company recorded unrealized gains of $19 million and unrealized losses of $51 million related to certain of these equity investments still held at December 31, 2024. During 2023, the Company recorded unrealized gains of $10 million and unrealized losses of $61 million related to certain of these equity investments still held at December 31, 2023. Cumulative unrealized gains and cumulative unrealized losses based on observable price changes for investments in equity investments without readily determinable fair values still held at December 31, 2024 were $309 million and $107 million, respectively.
At December 31, 2024, 2023 and 2022, the Company also had $267 million, $417 million and $598 million, respectively, recorded in Other Assets for equity securities held through ownership interests in investment funds. Losses recorded in Other (income) expense, net relating to these investment funds were $29 million, $106 million and $1.0 billion for the years ended December 31, 2024, 2023 and 2022, respectively.
Fair Value Measurements
Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company uses a fair value hierarchy which maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. There are three levels of inputs used to measure fair value with Level 1 having the highest priority and Level 3 having the lowest:
Level 1 — Quoted prices (unadjusted) in active markets for identical assets or liabilities.
Level 2 — Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3 — Unobservable inputs that are supported by little or no market activity. Level 3 assets or liabilities are those whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques with significant unobservable inputs, as well as assets or liabilities for which the determination of fair value requires significant judgment or estimation.
If the inputs used to measure the financial assets and liabilities fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument.
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis
Financial assets and liabilities measured at fair value on a recurring basis at December 31 are summarized below:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3TotalLevel 1Level 2Level 3Total
  20242023
Assets
Investments
Commercial paper$ $348 $ $348 $— $252 $— $252 
U.S. government and agency securities 99  99 — — — — 
Publicly traded equity securities463   463 252 — — 252 
 463 447  910 252 252 — 504 
Other assets (1)
U.S. government and agency securities89   89 72 — — 72 
Corporate notes and bonds    13 — — 13 
Publicly traded equity securities (2)
457   457 512 — — 512 
546   546 597 — — 597 
Derivative assets (3)
Forward exchange contracts 499  499 — 202 — 202 
Purchased currency options 213  213 — 83 — 83 
Interest rate swaps 17  17 — 57 — 57 
  729  729 — 342 — 342 
Total assets$1,009 $1,176 $ $2,185 $849 $594 $— $1,443 
Liabilities
Other liabilities
Contingent consideration$ $ $193 $193 $— $— $354 $354 
Derivative liabilities (3)
Forward exchange contracts 338  338 — 239 — 239 
Written currency options 7  7 — — — — 
 345  345 — 239 — 239 
Total liabilities$ $345 $193 $538 $— $239 $354 $593 
(1)    Investments included in other assets are restricted as to use, including for the payment of benefits under employee benefit plans.
(2)    Balance at December 31, 2024 includes securities with a fair value of $81 million, which are subject to a contractual sale restriction that expires in March 2025. Balance at December 31, 2023 includes securities with a fair value of $177 million, which were subject to a contractual sale restriction that expired in July 2024.
(3)    The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.
As of December 31, 2024 and 2023, Cash and cash equivalents included $12.3 billion and $6.0 billion of cash equivalents, respectively (which would be considered Level 2 in the fair value hierarchy).
Contingent Consideration
Summarized information about the changes in the fair value of liabilities for contingent consideration associated with business combinations is as follows:
20242023
Fair value January 1$354 $456 
Changes in estimated fair value (1)
(10)15 
Payments(151)(117)
Fair value December 31 (2)
$193 $354 
(1)    Recorded in Cost of sales, Research and development expenses, and Other (income) expense, net. Includes cumulative translation adjustments.
(2)    Balance at December 31, 2024 includes $148 million of current liabilities, of which $123 million relates to the termination of the Sanofi Pasteur MSD joint venture in 2016. As part of the termination, Merck recorded a liability for contingent future royalty payments of 11.5% on net sales of all Merck products that were previously sold by the joint venture through December 31, 2024. The fair value of this liability is determined utilizing the estimated amount and timing of projected cash flows using a risk-adjusted discount rate to present value the cash flows.
The payments of contingent consideration in 2024 include $126 million related to the Sanofi Pasteur MSD liabilities described above and $25 million related to the first commercial sale of Lyfnua (gefapixant) in the European Union (EU). The payments of contingent consideration in 2023 relate to the Sanofi Pasteur MSD liabilities.
Other Fair Value Measurements
Some of the Company’s financial instruments, such as cash and cash equivalents, receivables and payables, are reflected in the balance sheet at carrying value, which approximates fair value due to their short-term nature.
The estimated fair value of loans payable and long-term debt (including current portion) at December 31, 2024, was $32.6 billion compared with a carrying value of $37.1 billion and at December 31, 2023, was $32.0 billion compared with a carrying value of $35.1 billion. Fair value was estimated using recent observable market prices and would be considered Level 2 in the fair value hierarchy.
Concentrations of Credit Risk
On an ongoing basis, the Company monitors concentrations of credit risk associated with corporate and government issuers of securities and financial institutions with which it conducts business. Credit exposure limits are established to limit a concentration with any single issuer or institution. Cash and investments are placed in instruments that meet high credit quality standards, as specified in the Company’s investment policy guidelines.
The majority of the Company’s accounts receivable arise from product sales in the U.S., Europe and China and are primarily due from drug wholesalers, distributors and retailers, hospitals and government agencies. The Company monitors the financial performance and creditworthiness of its customers so that it can properly assess and respond to changes in their credit profile. The Company also continues to monitor global economic conditions, including the volatility associated with international sovereign economies, and associated impacts on the financial markets and its business. 
The Company’s customers with the largest accounts receivable balances are: McKesson Corporation, Cencora, Inc. and Cardinal Health, Inc., which represented approximately 21%, 21% and 13%, respectively, of total accounts receivable at December 31, 2024. Vaccines distributed by Chongqing Zhifei Biological Products Co., Ltd. (Zhifei) represent a substantial portion of total sales in China; however, nearly all of the accounts receivable for Zhifei were factored as of December 31, 2024, as part of the Company’s factoring program discussed below. The Company monitors the creditworthiness of its customers to which it grants credit terms in the normal course of business. Bad debts have been minimal. The Company does not normally require collateral or other security to support credit sales.
The Company has accounts receivable factoring agreements with financial institutions in certain countries to sell accounts receivable. The Company factored $2.1 billion and $3.0 billion of accounts receivable as of December 31, 2024 and 2023, respectively, under these factoring arrangements, which reduced outstanding accounts receivable. The cash received from the financial institutions is reported within operating activities in the Consolidated Statement of Cash Flows. In certain of these factoring arrangements, for ease of administration, the Company will collect customer payments related to the factored receivables, which it then remits to the financial institutions, generally within thirty days after receipt. At December 31, 2024 and 2023, the Company had collected $55 million and $44 million, respectively, on behalf of the financial institutions, which is reflected as restricted cash in Other current assets, and the related obligation to remit the cash is recorded in Accrued and other current liabilities. The net cash flows related to these collections are reported as financing activities in the Consolidated Statement of Cash Flows. The cost of factoring such accounts receivable was de minimis.
Derivative financial instruments are executed under International Swaps and Derivatives Association master agreements. The master agreements with several of the Company’s financial institution counterparties also include credit support annexes. These annexes contain provisions that require collateral to be exchanged depending on the value of the derivative assets and liabilities, the Company’s credit rating, and the credit rating of the counterparty. Cash collateral received by the Company from various counterparties was $165 million and $3 million at December 31, 2024 and 2023, respectively. The obligation to return such collateral is recorded in Accrued and other current liabilities.
v3.25.0.1
Inventories
12 Months Ended
Dec. 31, 2024
Inventory Disclosure [Abstract]  
Inventories Inventories
Inventories at December 31 consisted of:
20242023
Finished goods$2,022 $1,954 
Raw materials and work in process8,831 8,037 
Supplies289 277 

11,142 10,268 
Decrease to LIFO cost(840)(562)
 $10,302 $9,706 
Recognized as:
Inventories$6,109 $6,358 
Other Assets4,193 3,348 
Inventories valued under the LIFO method comprised approximately $3.4 billion and $3.1 billion at December 31, 2024 and 2023, respectively, after reflecting the decrease to LIFO cost. Amounts recognized as Other Assets are comprised almost entirely of raw materials and work in process inventories. At December 31, 2024 and 2023, these amounts included $3.8 billion and $2.6 billion, respectively, of inventories not expected to be sold within one year. In addition, these amounts included $412 million and $790 million at December 31, 2024 and 2023, respectively, of inventories produced in preparation for product launches.
v3.25.0.1
Goodwill and Other Intangibles
12 Months Ended
Dec. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and Other Intangibles Goodwill and Other Intangibles
The following table summarizes goodwill activity by segment:
PharmaceuticalAnimal HealthTotal
Balance January 1, 2023
$17,936 $3,268 $21,204 
Other (1)
(14)(7)
Balance December 31, 2023 (2)
17,922 3,275 21,197 
Acquisitions
 518 518 
Other (1)
(19)(28)(47)
Balance December 31, 2024 (2)
$17,903 $3,765 $21,668 
(1)    Includes cumulative translation adjustments on goodwill balances.
(2)    Accumulated goodwill impairment losses were $531 million at both December 31, 2024 and 2023.
Other acquired intangibles at December 31 consisted of:
 20242023
Gross
Carrying
Amount
Accumulated
Amortization
NetGross
Carrying
Amount
Accumulated
Amortization
Net
Product rights
$29,988 $19,066 $10,922 $23,643 $17,765 $5,878 
IPR&D430  430 6,816 — 6,816 
Trade names2,881 954 1,927 2,881 776 2,105 
Licenses and other8,863 5,772 3,091 8,263 5,051 3,212 
 $42,162 $25,792 $16,370 $41,603 $23,592 $18,011 
Some of the more significant acquired intangibles included in product rights, on a net basis, related to human health marketed products at December 31, 2024 were Winrevair, $5.9 billion; Reblozyl, $2.8 billion; and Zerbaxa, $260 million. Additionally, the Company had $4.3 billion of net acquired intangibles related to animal health at December 31, 2024, of which $1.7 billion related to product rights and $1.9 billion was attributable to trade names, primarily related to Allflex. At December 31, 2024, IPR&D primarily relates to MK-1026 (nemtabrutinib), obtained through the acquisition of ArQule, Inc. (ArQule), which had a balance of $418 million. Some of the more significant net intangible assets included in licenses and other above at December 31, 2024 include Lynparza, $1.2 billion, related to a collaboration with AstraZeneca; Lenvima, $442 million, related to a collaboration with Eisai; and Adempas, $372 million, related to a collaboration with Bayer. See Note 4 for additional information related to the intangible assets associated with these collaborations.
IPR&D that the Company acquires through business combinations represents the fair value assigned to incomplete research projects which, at the time of acquisition, have not reached technological feasibility. Amounts capitalized as IPR&D are accounted for as indefinite-lived intangible assets, subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each IPR&D project, the Company will make a separate determination as to the then-useful life of the asset and begin amortization.
In 2023, the Company recorded a $779 million IPR&D impairment charge within Research and development expenses related to MK-7264, gefapixant, a non-narcotic, oral selective P2X3 receptor antagonist, that was in development for the treatment of refractory or unexplained chronic cough in adults. In December 2023, the FDA issued a Complete Response Letter (CRL) regarding the resubmission of Merck’s New Drug Application (NDA) for gefapixant. In the CRL, the FDA concluded that Merck’s application did not meet substantial evidence of effectiveness for treating refractory chronic cough and unexplained chronic cough. The CRL was not related to the safety of gefapixant. The marketing application for gefapixant was based on results from the COUGH-1 and COUGH-2 clinical trials. In January 2022, the FDA issued a CRL regarding Merck’s original NDA for gefapixant. In that CRL, the FDA requested additional information related to the cough counting system that was used to assess efficacy. Receipt of the second CRL from the FDA constituted a triggering event that required the evaluation of the gefapixant intangible asset for impairment. The Company estimated the current fair value of gefapixant utilizing an income approach, which calculates the present value of projected future cash flows. The market participant assumptions used to derive the forecasted cash flows were updated to reflect revised market launch plans, resulting in a reduction in the estimated fair value. The revised estimated fair value of gefapixant when compared with its related carrying value resulted in the impairment charge noted above. The remaining intangible asset balance related to Lyfnua (gefapixant) at December 31, 2024 of $21 million is included in product rights in the table above and is being amortized over its expected useful life as supported by projected future cash flows in the markets where it is approved including Japan and the EU.
In 2022, the Company recorded $1.7 billion of intangible asset impairment charges within Research and development expenses, of which $1.6 billion represents IPR&D impairment charges related to nemtabrutinib (MK-1026), an oral, reversible, non-covalent Bruton’s tyrosine kinase (BTK) inhibitor currently being evaluated for the treatment of hematological malignancies that was obtained through the 2020 acquisition of ArQule. Following discussions with regulatory authorities in the third quarter of 2022, the development period for nemtabrutinib was extended, which constituted a triggering event that required the evaluation of the nemtabrutinib intangible asset for impairment. The Company estimated the current fair value of nemtabrutinib utilizing an income approach which calculates the present value of projected future cash flows. The market participant assumptions used to derive the forecasted cash flows were updated to reflect a delay in the anticipated launch date for nemtabrutinib, which resulted in lower cumulative revenue forecasts and a reduction in the estimated fair value. The revised estimated fair value of nemtabrutinib when compared with its related carrying value resulted in a $807 million impairment charge recorded in the third quarter of 2022. In December 2022, regulatory authorities provided additional feedback with respect to clinical study design that led to a further reassessment of the development plan for nemtabrutinib, which was expected to result in changes to the clinical study design, and corresponding delays in the anticipated approval and launch timelines, which constituted a triggering event. Utilizing an income approach, the forecasted cash flows were updated to reflect a decline in forecasted revenue coupled with an increase in development cost forecasts, which reduced projected cash flows lowering the estimated fair value of nemtabrutinib. The revised estimated fair value of nemtabrutinib when compared with its then-related carrying value resulted in a $780 million impairment charge. The remaining IPR&D intangible asset related to nemtabrutinib is $418 million. If the assumptions used to estimate the fair value of nemtabrutinib prove to be incorrect and the development of nemtabrutinib does not progress as anticipated thereby adversely affecting projected future cash flows, the Company may record an additional impairment charge in the future and such charge could be material. The Company also recorded an $80 million intangible asset impairment charge in 2022 related to derazantinib resulting from the termination of the out-licensing agreement and the decision by Merck not to pursue development of derazantinib.
The IPR&D projects that remain in development are subject to the inherent risks and uncertainties in drug development and it is possible that the Company will not be able to successfully develop and complete the IPR&D programs and profitably commercialize the underlying product candidates.
The Company may recognize additional non-cash impairment charges in the future related to marketed products or pipeline programs and such charges could be material.
Aggregate amortization expense primarily recorded within Cost of sales was $2.4 billion in 2024, $2.0 billion in 2023 and $2.1 billion in 2022. The estimated aggregate amortization expense for each of the next five years is as follows: 2025, $2.4 billion; 2026, $2.3 billion; 2027, $2.1 billion; 2028, $1.8 billion; 2029, $1.5 billion.
v3.25.0.1
Loans Payable, Long-Term Debt and Leases
12 Months Ended
Dec. 31, 2024
Debt Disclosure [Abstract]  
Loans Payable, Long-Term Debt and Leases Loans Payable, Long-Term Debt and Leases
Loans Payable
Loans payable at December 31, 2024 included $2.5 billion of notes due in 2025 and $149 million of long-dated notes that are subject to repayment at the option of the holders. Loans payable at December 31, 2023 included $1.3 billion of notes due in 2024 and $69 million of long-dated notes that are subject to repayment at the option of the holders. The weighted-average interest rate of commercial paper borrowings was 5.18% and 5.14% for the years ended December 31, 2024 and 2023, respectively. There were no commercial paper borrowings outstanding at December 31, 2024 or 2023.

Long-Term Debt
Long-term debt at December 31 consisted of:
20242023
2.15% notes due 2031
$1,989 $1,988 
2.75% notes due 2051
1,980 1,980 
3.70% notes due 2045
1,980 1,979 
3.40% notes due 2029
1,742 1,740 
4.50% notes due 2033
1,509 1,547 
1.70% notes due 2027
1,497 1,495 
2.90% notes due 2061
1,484 1,484 
5.00% notes due 2053
1,482 1,481 
4.00% notes due 2049
1,474 1,473 
4.15% notes due 2043
1,240 1,240 
1.45% notes due 2030
1,240 1,238 
2.45% notes due 2050
1,216 1,214 
1.875% euro-denominated notes due 2026
1,041 1,103 
0.75% notes due 2026
998 996 
1.90% notes due 2028
996 995 
5.15% notes due 2063
987 987 
3.90% notes due 2039
987 986 
2.35% notes due 2040
986 985 
3.25% euro-denominated notes due 2032
880 — 
3.50% euro-denominated notes due 2037
877 — 
3.70% euro-denominated notes due 2044
876 — 
3.75% euro-denominated notes due 2054
873 — 
4.30% notes due 2030
746 745 
4.90% notes due 2044
740 740 
6.50% notes due 2033
702 707 
1.375% euro-denominated notes due 2036
517 548 
2.50% euro-denominated notes due 2034
517 548 
4.05% notes due 2028
498 497 
3.60% notes due 2042
492 492 
6.55% notes due 2037
404 406 
5.75% notes due 2036
339 339 
5.95% debentures due 2028
307 307 
5.85% notes due 2039
271 271 
6.40% debentures due 2028
251 250 
6.30% debentures due 2026
135 135 
2.75% notes due 2025
 2,498 
Other209 289 
$34,462 $33,683 
Other (as presented in the table above) includes borrowings at variable rates that resulted in effective interest rates of 5.02% and 4.82% for 2024 and 2023, respectively.
With the exception of the 6.30% debentures due 2026, the notes listed in the table above are redeemable in whole or in part, at Merck’s option at any time, at varying redemption prices. Effective as of November 3, 2009, the Company executed a full and unconditional guarantee of the then existing debt of its subsidiary Merck Sharp & Dohme LLC. (MSD) and MSD executed a full and unconditional guarantee of the then existing debt of the Company
(excluding commercial paper), including for payments of principal and interest. These guarantees do not extend to debt issued subsequent to that date.
In May 2024, MSD Netherlands Capital B.V., a wholly owned finance subsidiary of Merck, completed a registered public offering of €3.4 billion in aggregate principal amount of euro-dominated senior notes comprised of €850 million of 3.25% senior notes due 2032, €850 million of 3.50% senior notes due 2037, €850 million of 3.70% senior notes due 2044 and €850 million of 3.75% senior notes due 2054 (collectively, the Euronotes). The Company has fully and unconditionally guaranteed all of MSD Netherlands Capital B.V.’s obligations under the Euronotes and no other subsidiary of the Company will guarantee these obligations. MSD Netherlands Capital B.V. is a “finance subsidiary” as defined in Rule 13-01(a)(4)(vi) of Regulation S-X of the Exchange Act, with no assets or operations other than those related to the issuance, administration and repayment of the Euronotes. The financial condition, results of operations and cash flows of MSD Netherlands Capital B.V. are consolidated in the financial statements of the Company. The net cash proceeds from the offering were used for general corporate purposes.
Certain of the Company’s borrowings require that Merck comply with covenants and, at December 31, 2024, the Company was in compliance with these covenants.
The aggregate maturities of long-term debt for each of the next five years are as follows: 2025, $2.6 billion; 2026, $2.2 billion; 2027, $1.5 billion; 2028, $2.1 billion; 2029, $1.7 billion. Interest payments related to these debt obligations are as follows: 2025, $1.2 billion; 2026, $1.2 billion; 2027, $1.1 billion; 2028, $1.1 billion; 2029, $1.0 billion.
The Company has a $6.0 billion credit facility that matures in May 2028. The facility provides backup liquidity for the Company’s commercial paper borrowing facility and is to be used for general corporate purposes. The Company has not drawn funding from this facility.
Leases
The Company has operating leases primarily for manufacturing facilities, research and development facilities, corporate offices, employee housing, vehicles and certain equipment. The Company determines if an arrangement is a lease at inception. When evaluating contracts for embedded leases, the Company exercises judgment to determine if there is an explicit or implicit identified asset in the contract and if Merck controls the use of that asset. Embedded leases, primarily associated with contract manufacturing organizations, are immaterial. The lease term includes options to extend or terminate the lease when it is reasonably certain that Merck will exercise that option. Real estate leases for facilities have an average remaining lease term of approximately six years, which include options to extend the leases for up to five years where applicable. Vehicle leases are generally in effect for four years. The Company elected to exclude short-term leases (leases with an initial term of 12 months or less) from the lease assets and liabilities on the balance sheet.
Lease expense for operating lease payments is recognized on a straight-line basis over the term of the lease. Operating lease assets and liabilities are recognized based on the present value of lease payments over the lease term. Since the Company’s leases do not have a readily determinable implicit discount rate, the Company uses its incremental borrowing rate to calculate the present value of lease payments by asset class. On a quarterly basis, an updated incremental borrowing rate is determined based on the average remaining lease term of each asset class and the Company’s pretax cost of debt for that same term. The updated rates for each asset class are applied prospectively to new leases. The Company does not separate lease components (e.g., payments for rent, real estate taxes and insurance costs) from non-lease components (e.g. common-area maintenance costs) in the event that the agreement contains both. Merck includes both the lease and non-lease components for purposes of calculating the right-of-use asset and related lease liability (if the non-lease components are fixed). For vehicle leases and employee housing, the Company applies a portfolio approach to account for the operating lease assets and liabilities.
Certain of the Company’s lease agreements contain variable lease payments that are adjusted periodically for inflation or for actual operating expense true-ups compared with estimated amounts; however, these amounts are immaterial. Sublease income was immaterial and there were no sale and leaseback transactions in 2024. Merck’s lease agreements do not contain any material residual value guarantees or material restrictive covenants.
Operating lease cost was $348 million in 2024, $339 million in 2023 and $334 million in 2022. Cash paid for amounts included in the measurement of operating lease liabilities was $357 million in 2024, $347 million in 2023 and $335 million in 2022. Operating lease assets obtained in exchange for lease obligations were $47 million in 2024, $122 million in 2023 and $57 million in 2022.
Supplemental balance sheet information related to operating leases is as follows:
December 3120242023
Assets
Other Assets (1)
$1,370 $1,437 
Liabilities
Accrued and other current liabilities282 285 
Other Noncurrent Liabilities877 928 
$1,159 $1,213 
Weighted-average remaining lease term (years)6.07.0
Weighted-average discount rate3.2 %3.3 %
(1)    Includes prepaid leases that have no related lease liability.
Maturities of operating leases liabilities are as follows:
2025$329 
2026292 
2027235 
2028146 
2029116 
Thereafter403 
Total lease payments1,521 
Less: Imputed interest362 
$1,159 
At December 31, 2024, the Company had entered into additional real estate operating leases that had not yet commenced; the obligations associated with these leases total $183 million.
Loans Payable, Long-Term Debt and Leases Loans Payable, Long-Term Debt and Leases
Loans Payable
Loans payable at December 31, 2024 included $2.5 billion of notes due in 2025 and $149 million of long-dated notes that are subject to repayment at the option of the holders. Loans payable at December 31, 2023 included $1.3 billion of notes due in 2024 and $69 million of long-dated notes that are subject to repayment at the option of the holders. The weighted-average interest rate of commercial paper borrowings was 5.18% and 5.14% for the years ended December 31, 2024 and 2023, respectively. There were no commercial paper borrowings outstanding at December 31, 2024 or 2023.

Long-Term Debt
Long-term debt at December 31 consisted of:
20242023
2.15% notes due 2031
$1,989 $1,988 
2.75% notes due 2051
1,980 1,980 
3.70% notes due 2045
1,980 1,979 
3.40% notes due 2029
1,742 1,740 
4.50% notes due 2033
1,509 1,547 
1.70% notes due 2027
1,497 1,495 
2.90% notes due 2061
1,484 1,484 
5.00% notes due 2053
1,482 1,481 
4.00% notes due 2049
1,474 1,473 
4.15% notes due 2043
1,240 1,240 
1.45% notes due 2030
1,240 1,238 
2.45% notes due 2050
1,216 1,214 
1.875% euro-denominated notes due 2026
1,041 1,103 
0.75% notes due 2026
998 996 
1.90% notes due 2028
996 995 
5.15% notes due 2063
987 987 
3.90% notes due 2039
987 986 
2.35% notes due 2040
986 985 
3.25% euro-denominated notes due 2032
880 — 
3.50% euro-denominated notes due 2037
877 — 
3.70% euro-denominated notes due 2044
876 — 
3.75% euro-denominated notes due 2054
873 — 
4.30% notes due 2030
746 745 
4.90% notes due 2044
740 740 
6.50% notes due 2033
702 707 
1.375% euro-denominated notes due 2036
517 548 
2.50% euro-denominated notes due 2034
517 548 
4.05% notes due 2028
498 497 
3.60% notes due 2042
492 492 
6.55% notes due 2037
404 406 
5.75% notes due 2036
339 339 
5.95% debentures due 2028
307 307 
5.85% notes due 2039
271 271 
6.40% debentures due 2028
251 250 
6.30% debentures due 2026
135 135 
2.75% notes due 2025
 2,498 
Other209 289 
$34,462 $33,683 
Other (as presented in the table above) includes borrowings at variable rates that resulted in effective interest rates of 5.02% and 4.82% for 2024 and 2023, respectively.
With the exception of the 6.30% debentures due 2026, the notes listed in the table above are redeemable in whole or in part, at Merck’s option at any time, at varying redemption prices. Effective as of November 3, 2009, the Company executed a full and unconditional guarantee of the then existing debt of its subsidiary Merck Sharp & Dohme LLC. (MSD) and MSD executed a full and unconditional guarantee of the then existing debt of the Company
(excluding commercial paper), including for payments of principal and interest. These guarantees do not extend to debt issued subsequent to that date.
In May 2024, MSD Netherlands Capital B.V., a wholly owned finance subsidiary of Merck, completed a registered public offering of €3.4 billion in aggregate principal amount of euro-dominated senior notes comprised of €850 million of 3.25% senior notes due 2032, €850 million of 3.50% senior notes due 2037, €850 million of 3.70% senior notes due 2044 and €850 million of 3.75% senior notes due 2054 (collectively, the Euronotes). The Company has fully and unconditionally guaranteed all of MSD Netherlands Capital B.V.’s obligations under the Euronotes and no other subsidiary of the Company will guarantee these obligations. MSD Netherlands Capital B.V. is a “finance subsidiary” as defined in Rule 13-01(a)(4)(vi) of Regulation S-X of the Exchange Act, with no assets or operations other than those related to the issuance, administration and repayment of the Euronotes. The financial condition, results of operations and cash flows of MSD Netherlands Capital B.V. are consolidated in the financial statements of the Company. The net cash proceeds from the offering were used for general corporate purposes.
Certain of the Company’s borrowings require that Merck comply with covenants and, at December 31, 2024, the Company was in compliance with these covenants.
The aggregate maturities of long-term debt for each of the next five years are as follows: 2025, $2.6 billion; 2026, $2.2 billion; 2027, $1.5 billion; 2028, $2.1 billion; 2029, $1.7 billion. Interest payments related to these debt obligations are as follows: 2025, $1.2 billion; 2026, $1.2 billion; 2027, $1.1 billion; 2028, $1.1 billion; 2029, $1.0 billion.
The Company has a $6.0 billion credit facility that matures in May 2028. The facility provides backup liquidity for the Company’s commercial paper borrowing facility and is to be used for general corporate purposes. The Company has not drawn funding from this facility.
Leases
The Company has operating leases primarily for manufacturing facilities, research and development facilities, corporate offices, employee housing, vehicles and certain equipment. The Company determines if an arrangement is a lease at inception. When evaluating contracts for embedded leases, the Company exercises judgment to determine if there is an explicit or implicit identified asset in the contract and if Merck controls the use of that asset. Embedded leases, primarily associated with contract manufacturing organizations, are immaterial. The lease term includes options to extend or terminate the lease when it is reasonably certain that Merck will exercise that option. Real estate leases for facilities have an average remaining lease term of approximately six years, which include options to extend the leases for up to five years where applicable. Vehicle leases are generally in effect for four years. The Company elected to exclude short-term leases (leases with an initial term of 12 months or less) from the lease assets and liabilities on the balance sheet.
Lease expense for operating lease payments is recognized on a straight-line basis over the term of the lease. Operating lease assets and liabilities are recognized based on the present value of lease payments over the lease term. Since the Company’s leases do not have a readily determinable implicit discount rate, the Company uses its incremental borrowing rate to calculate the present value of lease payments by asset class. On a quarterly basis, an updated incremental borrowing rate is determined based on the average remaining lease term of each asset class and the Company’s pretax cost of debt for that same term. The updated rates for each asset class are applied prospectively to new leases. The Company does not separate lease components (e.g., payments for rent, real estate taxes and insurance costs) from non-lease components (e.g. common-area maintenance costs) in the event that the agreement contains both. Merck includes both the lease and non-lease components for purposes of calculating the right-of-use asset and related lease liability (if the non-lease components are fixed). For vehicle leases and employee housing, the Company applies a portfolio approach to account for the operating lease assets and liabilities.
Certain of the Company’s lease agreements contain variable lease payments that are adjusted periodically for inflation or for actual operating expense true-ups compared with estimated amounts; however, these amounts are immaterial. Sublease income was immaterial and there were no sale and leaseback transactions in 2024. Merck’s lease agreements do not contain any material residual value guarantees or material restrictive covenants.
Operating lease cost was $348 million in 2024, $339 million in 2023 and $334 million in 2022. Cash paid for amounts included in the measurement of operating lease liabilities was $357 million in 2024, $347 million in 2023 and $335 million in 2022. Operating lease assets obtained in exchange for lease obligations were $47 million in 2024, $122 million in 2023 and $57 million in 2022.
Supplemental balance sheet information related to operating leases is as follows:
December 3120242023
Assets
Other Assets (1)
$1,370 $1,437 
Liabilities
Accrued and other current liabilities282 285 
Other Noncurrent Liabilities877 928 
$1,159 $1,213 
Weighted-average remaining lease term (years)6.07.0
Weighted-average discount rate3.2 %3.3 %
(1)    Includes prepaid leases that have no related lease liability.
Maturities of operating leases liabilities are as follows:
2025$329 
2026292 
2027235 
2028146 
2029116 
Thereafter403 
Total lease payments1,521 
Less: Imputed interest362 
$1,159 
At December 31, 2024, the Company had entered into additional real estate operating leases that had not yet commenced; the obligations associated with these leases total $183 million.
v3.25.0.1
Contingencies and Environmental Liabilities
12 Months Ended
Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]  
Contingencies and Environmental Liabilities Contingencies and Environmental Liabilities
The Company is involved in various claims and legal proceedings of a nature considered normal to its business, including product liability, intellectual property, commercial litigation, and securities litigation, as well as certain additional matters including governmental and environmental matters. In the opinion of the Company, it is unlikely that the resolution of these matters will be material to the Company’s financial condition, results of operations or cash flows.
Given the nature of the litigation discussed below and the complexities involved in these matters, the Company is unable to reasonably estimate a possible loss or range of possible loss for such matters until the Company knows, among other factors, (i) what claims, if any, will survive dispositive motion practice, (ii) the extent of the claims, including the size of any potential class, particularly when damages are not specified or are indeterminate, (iii) how the discovery process will affect the litigation, (iv) the settlement posture of the other parties to the litigation and (v) any other factors that may have a material effect on the litigation.
The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. These accruals are adjusted periodically as assessments change or additional information becomes available. Generally, for product liability claims, a portion of the overall accrual is actuarially determined and considers such factors as past experience, number of claims reported and estimates of claims incurred but not yet reported. Individually significant contingent losses are accrued when probable and reasonably estimable. Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable.
The Company’s decision to obtain insurance coverage is dependent on market conditions, including cost and availability, existing at the time such decisions are made. The Company has evaluated its risks and has determined that the cost of obtaining product liability insurance outweighs the likely benefits of the coverage that is available and, as such, has no insurance for most product liabilities.
Product Liability Litigation
Dr Scholl’s Foot Powder
As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. arising from consumers’ alleged exposure to talc in Dr. Scholl’s foot powder, which Merck acquired through its merger with Schering-Plough Corporation and sold as part of the divestiture of Merck’s consumer care business to Bayer in 2014. In these actions, plaintiffs allege that they were exposed to asbestos-contaminated talc and developed mesothelioma as a result. As of December 31, 2024, approximately 415 cases were pending against Merck in various state courts.
Gardasil/Gardasil 9
As previously disclosed, Merck is a defendant in product liability lawsuits in the U.S. involving Gardasil (Human Papillomavirus Quadrivalent [Types 6, 11, 16 and 18] Vaccine, Recombinant) and Gardasil 9 (Human Papillomavirus 9-valent Vaccine, Recombinant). As of December 31, 2024, approximately 225 cases were filed and pending against Merck in either federal or state court. In these actions, plaintiffs allege, among other things, that they suffered various personal injuries after vaccination with Gardasil or Gardasil 9, with postural orthostatic tachycardia syndrome (POTS) as a predominate alleged injury. In August 2022, the U.S. Judicial Panel on Multidistrict Litigation ordered that Gardasil/Gardasil 9 product liability cases pending in federal courts nationwide be transferred to Judge Robert J. Conrad in the Western District of North Carolina for coordinated pre-trial proceedings. In February 2024, the multidistrict litigation was reassigned to Judge Kenneth D. Bell. As previously disclosed, there are fewer than 15 product liability cases pending outside the U.S.
On January 28, 2025, a trial commenced in California state court. Plaintiff claims that she suffers from POTS and fibromyalgia as a result of her Gardasil vaccinations. On February 14, 2025, after four weeks of trial and an opportunity to litigate plaintiff’s claims before a jury, plaintiff’s counsel approached Merck and proposed that the jury be discharged and the case adjourned. Merck agreed, subject to an explicit stipulation that Merck would provide no financial or other consideration in exchange for the agreement to adjourn. The case has thus been adjourned until a new trial date of September 15, 2025. Merck is vigorously defending this case and believes that evidence presented in court will show that Gardasil had no role in causing any of plaintiff’s conditions.
Governmental Proceedings
Civil Investigative Demands
As previously disclosed, in June 2024, Merck received a Civil Investigative Demand (CID) from the U.S. Department of Justice, pursuant to a False Claims Act investigation, seeking documents and materials related to Steglatro, Januvia and certain related drugs. The CID states that it is investigating Merck’s price reporting under the Medicaid Drug Rebate Program as well as compliance with anti-kickback requirements in connection with patient assistance programs. The Company is cooperating with the investigation.
As previously disclosed, in June 2020, Merck received a CID from the U.S. Department of Justice. The CID requests answers to interrogatories, as well as various documents, regarding temperature excursions at a third-party storage facility containing certain Merck products. Merck is cooperating with the government’s investigation and intends to produce information and/or documents as necessary in response to the CID.
Inflation Reduction Act
As previously disclosed, in June 2023, Merck filed a complaint in the U.S. District Court for the District of Columbia against the U.S. government regarding the Inflation Reduction Act’s “Drug Price Negotiation Program” for Medicare (the Program). This litigation seeks relief from the Program by challenging its constitutionality as violative of the First and Fifth Amendments to the U.S. Constitution.
Other Matters
As previously disclosed, in April 2019, Merck received a set of investigative interrogatories from the California Attorney General’s Office pursuant to its investigation of conduct and agreements that allegedly affected or delayed competition to Lantus in the insulin market. The interrogatories seek information concerning Merck’s development of an insulin glargine product, and its subsequent termination, as well as Merck’s patent litigation against Sanofi S.A. concerning Lantus and the resolution of that litigation. Merck is cooperating with the California Attorney General’s investigation.
As previously disclosed, from time to time, the Company’s subsidiaries in China receive inquiries regarding their operations from various Chinese governmental agencies. Some of these inquiries may be related to matters involving other multinational pharmaceutical companies, as well as Chinese entities doing business with such companies. The Company’s policy is to cooperate with these authorities and to provide responses as appropriate.
As previously disclosed, from time to time, the Company receives inquiries and is the subject of preliminary investigation activities from competition and other governmental authorities in markets outside the U.S. These authorities may include regulators, administrative authorities, and law enforcement and other similar officials, and these preliminary investigation activities may include site visits, formal or informal requests or demands for documents or materials, inquiries or interviews and similar matters. Certain of these preliminary inquiries or activities may lead to the commencement of formal proceedings. Should those proceedings be determined adversely to the Company, monetary fines and/or remedial undertakings may be required.
Securities Litigation
In February 2025, a putative class action was filed against Merck and certain of its officers in the U.S. District Court for the District of New Jersey purportedly on behalf of all purchasers of Merck common stock between February 2022 and February 2025. Plaintiff alleges that Merck violated federal securities laws by making materially false and misleading statements and material omissions regarding demand for Gardasil/Gardasil 9 in China. Plaintiff seeks unspecified monetary damages, pre-judgment and post-judgment interest, and fees and costs.
Commercial and Other Litigation
Zetia Antitrust Litigation
As previously disclosed, Merck, MSD, Schering Corporation, Schering-Plough Corporation, and MSP Singapore Company LLC (collectively, the Merck Defendants) were defendants in a number of lawsuits filed in 2018 on behalf of direct and indirect purchasers of Zetia (ezetimibe) alleging violations of federal and state antitrust laws, as well as other state statutory and common law causes of action. The cases were consolidated in a federal multidistrict litigation (Zetia MDL) before Judge Rebecca Beach Smith in the Eastern District of Virginia. In April 2023, the Merck Defendants reached settlements with the direct purchaser and retailer plaintiffs and a settlement with the indirect purchaser class that the court approved in October 2023.
As previously disclosed, in 2020 and 2021, United Healthcare Services, Inc. (United Healthcare), Humana Inc. (Humana), Centene Corporation and others (Centene), and Kaiser Foundation Health Plan, Inc. (Kaiser) (collectively, the Insurer Plaintiffs), each filed a lawsuit in a jurisdiction outside of the Eastern District of Virginia against the Merck Defendants and others, making similar allegations as those made in the Zetia MDL, as well as additional allegations about Vytorin. These cases were transferred to the Eastern District of Virginia to proceed with the Zetia MDL.
In December 2023, the U.S. Judicial Panel on Multidistrict Litigation remanded the four Insurer Plaintiff cases to the transferor courts in the Northern District of California (Kaiser), the District of Minnesota (United Healthcare), and the District of New Jersey (Humana and Centene). The Merck Defendants filed motions to dismiss in each of the Insurer Plaintiff cases. On December 30, 2024, the court granted in part and denied in part the motions to dismiss in the Humana and Centene cases, and on January 29, 2025, Humana and Centene filed amended complaints.
RotaTeq Antitrust Litigation
As previously disclosed, in March 2023, the Mayor and City Council of Baltimore filed a putative class action against MSD in the Eastern District of Pennsylvania on behalf of all third-party payors in 35 states that indirectly purchased, paid, and/or provided reimbursement for some or all of the purchase price of RotaTeq (Rotavirus Vaccine, Live Oral, Pentavalent), other than for resale, from March 3, 2019 to the present. Plaintiff alleges that MSD violated federal and state antitrust laws and state consumer protection laws. Plaintiff alleges that MSD has implemented an anticompetitive vaccine bundling scheme whereby MSD leverages its alleged monopoly power in certain pediatric vaccine markets to maintain its alleged monopoly power in the U.S. market for rotavirus vaccines in order to charge supracompetitive prices for RotaTeq. Plaintiff seeks permanent injunctive relief and unspecified monetary damages on purchases of RotaTeq, trebled, and fees and costs. In May 2023, MSD moved to dismiss the complaint. In November 2023, the court granted in part and denied in part the motion to dismiss, dismissing plaintiff’s Idaho and Utah consumer law claims and allowing all other claims to proceed.
Bravecto Litigation
As previously disclosed, in January 2020, the Company was served with a complaint in the U.S. District Court for the District of New Jersey. Following motion practice, the plaintiffs filed a third amended complaint in August 2024, seeking to certify a nationwide class action of purchasers or users of Bravecto (fluralaner) products in the U.S. or its territories between May 1, 2014 and July 1, 2021. Plaintiffs contend Bravecto causes neurological events in dogs and cats and alleges violations of the New Jersey Consumer Fraud Act, Breach of Warranty, Product Liability, and related theories. The Company moved to dismiss or, alternatively, to strike the class allegations from the third amended complaint, and that motion is pending. A similar case was filed in Quebec, Canada in May 2019. The
Superior Court certified a class of dog owners in Quebec who gave Bravecto Chew to their dogs between February 16, 2017 and November 2, 2018 whose dogs experienced one of the conditions in the post-marketing adverse reactions section of the labeling approved on November 2, 2018. The Company and plaintiffs each appealed the class certification decision. The Court of Appeal of Quebec amended the class period to start July 2, 2014, allowed the second plaintiff to serve as a class representative, and modified the list of conditions in the class definition. The Company sought leave to appeal to the Supreme Court of Canada, which was denied. The case is proceeding in the Superior Court.
340B Program Litigation
As previously disclosed, Merck filed a complaint in the U.S. District Court for the District of Columbia to challenge the letter Merck received from the U.S. Health Resources and Services Administration (HRSA) in May 2022 regarding Merck’s 340B Program integrity initiative. On September 17, 2024, the court entered a consent judgment granting Merck the relief it had sought in the litigation, including declarations that HRSA’s May 2022 letter was unlawful and that the version of Merck’s 340B Program integrity initiative at issue in the litigation did not violate Section 340B on its face.
Qui Tam Litigation
As previously disclosed, in June 2012, the U.S. District Court for the Eastern District of Pennsylvania unsealed a complaint that had been filed against the Company under the federal False Claims Act by two former employees alleging, among other things, that the Company defrauded the U.S. government by falsifying data in connection with a clinical study conducted on the mumps component of the Company’s M-M-R II vaccine. The complaint alleges the fraud took place between 1999 and 2001. The U.S. government had the right to participate in and take over the prosecution of this lawsuit but notified the court that it declined to exercise that right. The two former employees pursued the lawsuit without the involvement of the U.S. government. In July 2023, the court denied relators’ motion for summary judgment, granted two of the Company’s motions for summary judgment, and denied the Company’s remaining motions for summary judgment as moot. The court entered judgment in favor of the Company and dismissed relators’ amended complaint in full with prejudice. Relators appealed that decision, and in August 2024, the Third Circuit affirmed the district court’s decision.
In addition, as previously disclosed, two putative class action lawsuits on behalf of direct purchasers of the M‑M‑R II vaccine, which charge that the Company misrepresented the efficacy of the M-M-R II vaccine in violation of federal antitrust laws and various state consumer protection laws, are pending in the Eastern District of Pennsylvania. The court granted the Company’s motion for summary judgment as to plaintiffs’ state law claims and denied the motion as to plaintiffs’ antitrust claim. The Company appealed, and on October 7, 2024, the Third Circuit reversed-in-part the district court’s order and remanded the case with instructions to enter summary judgment for the Company. On November 20, 2024, plaintiffs-appellees filed a petition for rehearing and rehearing en banc, and on February 10, 2025, the court denied the petition.
Merck KGaA Litigation
As previously disclosed, in January 2016, to protect its long-established brand rights in the U.S., the Company filed a lawsuit against Merck KGaA, Darmstadt, Germany (KGaA), historically operating as the EMD Group in the U.S., alleging it improperly uses the name “Merck” in the U.S. KGaA has filed suit against the Company in a number of jurisdictions outside of the U.S. alleging, among other things, unfair competition, trademark infringement and/or corporate name infringement. In certain of those jurisdictions, KGaA also alleges breach of the parties’ coexistence agreement. The litigation is ongoing in the U.S. with no trial date set, and also ongoing in jurisdictions outside of the U.S.
Patent Litigation
From time to time, generic manufacturers of pharmaceutical products file abbreviated New Drug Applications (ANDAs) with the U.S. Food and Drug Administration (FDA) seeking to market generic forms of the Company’s products prior to the expiration of relevant patents owned by the Company. To protect its patent rights, the Company may file patent infringement lawsuits against such generic companies. Similar lawsuits defending the Company’s patent rights may exist in other countries. The Company intends to vigorously defend its patents, which it believes are valid, against infringement by companies attempting to market products prior to the expiration of such patents. As with any litigation, there can be no assurance of the outcomes, which, if adverse, could result in significantly shortened periods of exclusivity for these products and, with respect to products acquired through acquisitions accounted for as business combinations, potentially significant intangible asset impairment charges.
Bridion As previously disclosed, between January and November 2020, the Company received multiple Paragraph IV Certification Letters under the Hatch-Waxman Act notifying the Company that generic drug companies had filed applications to the FDA seeking pre-patent expiry approval to sell generic versions of Bridion (sugammadex)
Injection. In March, April and December 2020, the Company filed patent infringement lawsuits in the U.S. District Courts for the District of New Jersey and the Northern District of West Virginia against those generic companies. All actions in the District of New Jersey were consolidated. The West Virginia case was jointly dismissed with prejudice in August 2022 in favor of proceeding in New Jersey. The remaining defendants in the New Jersey action have stipulated to infringement of the asserted claims and withdrew all remaining claims and defenses other than a defense seeking to shorten the patent term extension (PTE) of the sugammadex patent to December 2022. The U.S. District Court for the District of New Jersey held a one-day trial in December 2022 on this remaining PTE calculation defense. The court ordered a post-trial briefing on this defense and held closing arguments in February 2023.
As previously disclosed, in June 2023, the U.S. District Court for the District of New Jersey ruled in Merck’s favor. The court held that Merck’s calculation of PTE for the sugammadex patent covering the compound is not invalid and that the U.S. Patent & Trademark Office correctly granted a full five-year extension. This ruling affirms and validates Merck’s U.S. patent protection for Bridion through at least January 2026. Also in June 2023, the U.S. District Court for the District of New Jersey issued a final judgment prohibiting the FDA from approving any of the pending or tentatively approved generic applications until January 27, 2026, except for any subsequent agreements between defendants and Merck or further order by the court.
In July 2023, defendants filed a notice of appeal with the U.S. Court of Appeals for the Federal Circuit. The appeal is currently pending. Oral argument took place on February 4, 2025.
While the New Jersey action was pending, the Company settled with five generic companies providing that these generic companies can bring their generic versions of Bridion to the market in January 2026 (which may be delayed by any applicable pediatric exclusivity) or earlier under certain circumstances. The Company agreed to stay the lawsuit filed against two generic companies, which in exchange agreed to be bound by a judgment on the merits of the consolidated action in the District of New Jersey. One of the generic companies in the consolidated action requested dismissal of the action against it and the Company did not oppose this request, which was subsequently granted by the court. The Company does not expect this company to bring its generic version of Bridion to the market before January 2026 or later, depending on any applicable pediatric exclusivity.
In February 2024, the Company received another Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Hikma Pharmaceuticals USA Inc. (Hikma) had filed an application to the FDA seeking pre-patent expiry approval to sell a generic version of Bridion Injection. In March 2024, the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Hikma, postponing FDA approval of the Hikma generic drug for 30 months or until expiration of the sugammadex patent (January 27, 2026) and any potentially applicable pediatric exclusivity or an adverse court decision, if any, whichever may occur earlier. Expiration of the patent, and any potentially applicable pediatric exclusivity, will occur earlier than expiry of the 30-month stay. On April 16, 2024, the district court stayed the case during the pendency of the Federal Circuit appeal noted above.
Januvia, Janumet, Janumet XR As previously disclosed, the FDA granted pediatric exclusivity with respect to Januvia (sitagliptin), Janumet (sitagliptin/metformin HCl), and Janumet XR (sitagliptin and metformin HCl extended-release), which provides a further six months of exclusivity in the U.S. beyond the expiration of all patents listed in the FDA’s Orange Book. Adding this exclusivity to the term of the key patent protection extended exclusivity on these products to January 2023. However, Januvia, Janumet, and Janumet XR contain sitagliptin phosphate monohydrate and the Company has another patent covering certain phosphate salt and polymorphic forms of sitagliptin that expires in May 2027, including pediatric exclusivity (salt/polymorph patent).
As previously disclosed, beginning in 2019, a number of generic drug companies filed ANDAs seeking approval of generic forms of Januvia and Janumet along with paragraph IV certifications challenging the validity of the salt/polymorph patent. The Company responded by filing infringement suits which have all been settled. The Company has settled with a total 26 generic companies providing that these generic companies can bring their generic versions of Januvia and Janumet to the market in the U.S. in May 2026 or earlier under certain circumstances, and their generic versions of Janumet XR to the market in July 2026 or earlier under certain circumstances.
In March 2021, the Company filed a patent infringement lawsuit in the U.S. District Court for the District of Delaware against Zydus Worldwide DMCC, Zydus Pharmaceuticals (USA) Inc., and Cadila Healthcare Ltd. (collectively, Zydus). In that lawsuit, the Company alleged infringement of the salt/polymorph patent based on the filing of Zydus’s NDA seeking approval of a form of sitagliptin that is a different from than that used in Januvia. In December 2022, the parties reached settlement that included dismissal of the case without prejudice enabling Zydus to seek final approval of a non-automatically substitutable product.
In January 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl tablets and certifying that no valid or enforceable claim of any of the patents listed in FDA’s Orange Book for Janumet will be infringed by the proposed Zydus product. In March 2023, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable product containing a different form of sitagliptin than that used in Janumet. In November 2023, the Company received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying the Company that Zydus filed an ANDA seeking approval of sitagliptin/metformin HCl Extended Release tablets. In January 2024, the parties reached settlement enabling Zydus to seek final approval of a non-automatically substitutable version containing a different form of sitagliptin than that used in Janumet XR.
As a result of these settlement agreements related to the later expiring salt/polymorph patent directed to the specific sitagliptin salt form of the products, the Company expects that Januvia and Janumet will not lose market exclusivity in the U.S. until May 2026 and Janumet XR will not lose market exclusivity in the U.S. until July 2026, although Zydus has received FDA approval for a non-automatically substitutable form of sitagliptin that differs from the form in the Company’s sitagliptin products.
In March 2024, the Company received another Paragraph IV Certification Letter under the Hatch-Waxman Act from Azurity Pharmaceuticals, Inc. (Azurity) asserting that a different sitagliptin product subject to its ANDA does not infringe the salt/polymorph patent. In May 2024, Merck filed a civil action in the U.S. District Court of Delaware alleging infringement. The case was dismissed without prejudice in July 2024. Following the dismissal, the Company granted Azurity a covenant not to assert the salt/polymorph patent against the Azurity product that is the subject of such ANDA.
Supplementary Protection Certificates (SPCs) for Janumet expired in April 2023 for the majority of European countries. Prior to expiration, generic companies sought revocation of the Janumet SPCs in a number of European countries. In February 2022, a Finnish court referred certain questions to the Court of Justice of the European Union that could impact the validity of the Janumet SPCs in Europe. A decision was rendered on December 19, 2024. The decision provides guidance on points of law and does not directly apply these to the Janumet SPCs. Thus, additional proceedings in certain countries where generic companies were prevented from launching products during the SPC period may be necessary to determine whether the SPCs are valid and if not, whether damages are appropriate. Those countries include Belgium, Czech Republic, Ireland, Finland, France, Slovakia and Switzerland. If the Janumet SPCs are ultimately upheld, the Company has reserved its rights related to the pursuit of damages for those countries where a generic launched prior to expiry of the Janumet SPC.
In October 2023, the Company filed a patent infringement lawsuit against Sawai Pharmaceuticals Co., Ltd. and Medisa Shinyaku Co., Ltd (collectively, Defendants) in the Tokyo District Court seeking an injunction to stop the manufacture, sale and offer for sale of the Defendants’ sitagliptin dihydrogen phosphate product, while the Company’s patents and patent term extensions are in force. The lawsuit is in response to the Defendants’ application for marketing authorization to sell a generic sitagliptin dihydrogen phosphate product, in the anhydrate form, which was approved in August 2023. Merck asserts that the Defendants’ activity infringes a patent term extension associated with Merck’s patent directed to the sitagliptin compound patent.
Keytruda As previously disclosed, in November 2022, the Company filed a complaint against The Johns Hopkins University (JHU) in the U.S. District Court of Maryland. This action concerns patents emerging from a joint research collaboration between Merck and JHU regarding the use of pembrolizumab, which Merck sells under the trade name Keytruda. Merck and JHU partnered to design and conduct a clinical study administering Keytruda to cancer patients having tumors that had the genetic biomarker known as microsatellite instability-high (MSI-H). After the conclusion of the study, JHU secured U.S. patents citing the joint research study. Merck alleges that JHU has breached the collaboration agreement by filing and obtaining these patents without informing or involving Merck and then licensing the patents to others. Merck therefore brought this action for breach of contract, declaratory judgment of noninfringement, and promissory estoppel. JHU answered the complaint in April and May 2023, denying Merck’s claims, and counterclaiming for willful infringement of nine issued U.S. patents, including a demand for damages. Between November 30, 2023 and March 13, 2024, the Company filed inter partes review petitions with the United States Patent & Trademark Office Patent Trial and Appeal Board (PTAB), challenging the validity of all nine patents asserted in the case. Between June 2024 and October 2024, the PTAB instituted a review of all nine asserted patents. In July 2024, the district court granted Merck’s motion to stay the case in its entirety pending the outcome of the PTAB proceeding instituted in June 2024.
Lynparza As previously disclosed, in December 2022, AstraZeneca Pharmaceuticals LP received a Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Natco Pharma Limited (Natco) has filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In February 2023, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S.
District Court for the District of New Jersey against Natco. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until June 2025 or until an adverse court decision, if any, whichever may occur earlier. In May, June, July, and November 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Natco asserting additional patents covering olaparib.
In December 2023, AstraZeneca Pharmaceuticals LP received a second Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Sandoz Inc. has filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In February 2024, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Sandoz. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until June 2026 or until an adverse court decision, if any, whichever may occur earlier. In May, July, and November 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Sandoz asserting additional patents covering olaparib.
In May 2024, AstraZeneca Pharmaceuticals LP received a third Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Cipla USA, Inc. and Cipla Limited (collectively, Cipla) filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In June 2024, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Cipla. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until November 2026 or until an adverse court decision, if any, whichever may occur earlier. In June, July, and November 2024, AstraZeneca and the Company filed additional patent infringement lawsuits in the U.S. District Court for the District of New Jersey against Cipla asserting additional patents covering olaparib.
In November 2024, AstraZeneca Pharmaceuticals LP received another Paragraph IV Certification Letter under the Hatch-Waxman Act notifying AstraZeneca that Zydus Pharmaceuticals (USA) Inc. filed an application to the FDA seeking pre-patent expiry approval to sell generic versions of Lynparza (olaparib) tablet. In November 2024, AstraZeneca and the Company filed a patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Zydus. This lawsuit, which asserts one or more patents covering olaparib, automatically stays FDA approval of the generic application until May 2027 or until an adverse court decision, if any, whichever may occur earlier. In November 2024, AstraZeneca and the Company filed an additional patent infringement lawsuit in the U.S. District Court for the District of New Jersey against Zydus asserting an additional patent covering olaparib.
Other Litigation
There are various other pending legal proceedings involving the Company, principally product liability and intellectual property lawsuits. While it is not feasible to predict the outcome of such proceedings, in the opinion of the Company, either the likelihood of loss is remote or any reasonably possible loss associated with the resolution of such proceedings is not expected to be material to the Company’s financial condition, results of operations or cash flows either individually or in the aggregate.
Legal Defense Reserves
Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. Some of the significant factors considered in the review of these legal defense reserves are as follows: the actual costs incurred by the Company; the development of the Company’s legal defense strategy and structure in light of the scope of its litigation; the number of cases being brought against the Company; the costs and outcomes of completed trials and the most current information regarding anticipated timing, progression, and related costs of pre-trial activities and trials in the associated litigation. The amount of legal defense reserves as of December 31, 2024 and 2023 of approximately $225 million and $210 million, respectively, represents the Company’s best estimate of the minimum amount of defense costs to be incurred in connection with its outstanding litigation; however, events such as additional trials and other events that could arise in the course of its litigation could affect the ultimate amount of legal defense costs to be incurred by the Company. The Company will continue to monitor its legal defense costs and review the adequacy of the associated reserves and may determine to increase the reserves at any time in the future if, based upon the factors set forth, it believes it would be appropriate to do so.
Environmental Matters
The Company and its subsidiaries are parties to a number of proceedings brought under the Comprehensive Environmental Response, Compensation and Liability Act, commonly known as Superfund, and other federal and state equivalents. These proceedings seek to require the operators of hazardous waste disposal facilities, transporters of waste to the sites and generators of hazardous waste disposed of at the sites to clean up the sites or
to reimburse the government for cleanup costs. The Company has been made a party to these proceedings as an alleged generator of waste disposed of at the sites. In each case, the government alleges that the defendants are jointly and severally liable for the cleanup costs. Although joint and several liability is alleged, these proceedings are frequently resolved so that the allocation of cleanup costs among the parties more nearly reflects the relative contributions of the parties to the site situation. The Company’s potential liability varies greatly from site to site. For some sites the potential liability is de minimis and for others the final costs of cleanup have not yet been determined. While it is not feasible to predict the outcome of many of these proceedings brought by federal or state agencies or private litigants, in the opinion of the Company, such proceedings should not ultimately result in any liability which would have a material adverse effect on the financial condition, results of operations or liquidity of the Company. The Company has taken an active role in identifying and accruing for these costs and such amounts do not include any reduction for anticipated recoveries of cleanup costs from former site owners or operators or other recalcitrant potentially responsible parties.
In management’s opinion, the liabilities for all environmental matters that are probable and reasonably estimable have been accrued and totaled $41 million and $42 million at December 31, 2024 and 2023, respectively. These liabilities are undiscounted, do not consider potential recoveries from other parties and will be paid out over the periods of remediation for the applicable sites, which are expected to occur primarily over the next 15 years. Although it is not possible to predict with certainty the outcome of these matters, or the ultimate costs of remediation, management does not believe that any reasonably possible expenditures that may be incurred in excess of the liabilities accrued should exceed approximately $46 million in the aggregate. Management also does not believe that these expenditures should result in a material adverse effect on the Company’s financial condition, results of operations or liquidity for any year.
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Equity
12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Equity Equity
The Merck certificate of incorporation authorizes 6,500,000,000 shares of common stock and 20,000,000 shares of preferred stock.
Capital Stock
A summary of common stock and treasury stock transactions (shares in millions) is as follows:
 202420232022
  Common
Stock
Treasury
Stock
Common
Stock
Treasury
Stock
Common
Stock
Treasury
Stock
Balance January 13,577 1,045 3,577 1,039 3,577 1,049 
Purchases of treasury stock 11 — 13 — — 
Issuances (1)
 (7)— (7)— (10)
Balance December 313,577 1,049 3,577 1,045 3,577 1,039 
(1)    Issuances primarily reflect activity under share-based compensation plans.
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Share-Based Compensation Plans
12 Months Ended
Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]  
Share-Based Compensation Plans Share-Based Compensation Plans
The Company has share-based compensation plans under which the Company grants restricted stock units (RSUs) and performance share units (PSUs) to certain management level employees. In addition, employees and non-employee directors may be granted options to purchase shares of Company common stock at the fair market value at the time of grant. These plans were approved by the Company’s shareholders.
At December 31, 2024, 75 million shares collectively were authorized for future grants under the Company’s share-based compensation plans. These awards are settled with treasury shares.
Employee stock options are granted to purchase shares of Company stock at the fair market value at the time of grant. These awards generally vest one-third each year over a three-year period, with a contractual term of 7-10 years. RSUs are stock awards that are granted to employees and entitle the holder to shares of common stock as the awards vest. The fair value of the stock option and RSU awards is determined and fixed on the grant date based on the Company’s stock price. PSUs are stock awards where the ultimate number of shares issued will be contingent on the Company’s performance against a pre-set objective or set of objectives. The fair value of each PSU is determined on the date of grant based on the Company’s stock price. For RSUs and PSUs, dividends declared during the vesting period are payable to the employees only upon vesting. Over the PSU performance period, the number of shares of stock that are expected to be issued will be adjusted based on the probability of achievement of a performance target and final compensation expense will be recognized based on the ultimate number of shares issued. RSU and PSU distributions will be in shares of Company stock after the end of the vesting or performance
period, subject to the terms applicable to such awards. PSU awards generally vest after three years. RSU awards generally vest one-third each year over a three-year period.
Total pretax share-based compensation cost recorded in 2024, 2023 and 2022 was $761 million, $645 million and $541 million, respectively. Income tax benefits for share-based compensation expense recognized in 2024, 2023 and 2022 were $117 million, $96 million and $78 million, respectively.
The Company uses the Black-Scholes option pricing model for determining the fair value of option grants. In applying this model, the Company uses both historical data and current market data to estimate the fair value of its options. The Black-Scholes model requires several assumptions including expected dividend yield, risk-free interest rate, volatility, and term of the options. The expected dividend yield is based on historical patterns of dividend payments. The risk-free interest rate is based on the rate at grant date of zero-coupon U.S. Treasury Notes with a term equal to the expected term of the option. Expected volatility is estimated using a blend of historical and implied volatility. The historical component is based on historical monthly price changes. The implied volatility is obtained from market data on the Company’s traded options. The expected life represents the amount of time that options granted are expected to be outstanding, based on historical and forecasted exercise behavior.
The weighted average exercise price of options granted in 2024, 2023 and 2022 was $129.22, $117.89 and $87.10 per option, respectively. The weighted average fair value of options granted in 2024, 2023 and 2022 was $25.60, $21.69 and $15.45 per option, respectively, and were determined using the following assumptions:
Years Ended December 31202420232022
Expected dividend yield3.0 %3.1 %3.1 %
Risk-free interest rate4.7 %3.4 %3.0 %
Expected volatility20.5 %22.4 %22.5 %
Expected life (years)5.85.85.9
Summarized information relative to stock option plan activity (options in thousands) is as follows:
Number
of Options
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Term (Years)
Aggregate
Intrinsic
Value
Outstanding January 1, 2024
13,527 $77.54 
Granted1,753 129.22 
Exercised(2,581)68.90 
Forfeited(199)111.48   
Outstanding December 31, 2024
12,500 $86.04 5.9$249 
Vested and expected to vest December 31, 202412,201 $85.10 5.9$249 
Exercisable December 31, 20249,084 $74.00 4.9$241 
Additional information pertaining to stock option plans is provided in the table below:
Years Ended December 31202420232022
Total intrinsic value of stock options exercised$144 $95 $225 
Fair value of stock options vested32 30 30 
Cash received from the exercise of stock options177 125 384 
A summary of nonvested RSU and PSU activity (shares in thousands) is as follows:
 RSUsPSUs
  Number
of Shares
Weighted
Average
Grant Date
Fair Value
Number
of Shares
Weighted
Average
Grant Date
Fair Value
Nonvested January 1, 2024
12,542 $100.10 1,966 $90.80 
Granted6,356 128.79 968 121.91 
Vested(6,091)92.97 (1,109)73.50 
Forfeited(575)113.18 (59)121.12 
Nonvested December 31, 202412,232 $117.94 1,766 $117.57 
Expected to vest December 31, 202410,976 $117.25 1,669 $116.26 
At December 31, 2024, there was $1.1 billion of total pretax unrecognized compensation expense related to nonvested stock options, RSU and PSU awards which will be recognized over a weighted average period of 1.9 years. For segment reporting, share-based compensation costs are unallocated expenses.
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Pension and Other Postretirement Benefit Plans
12 Months Ended
Dec. 31, 2024
Retirement Benefits [Abstract]  
Pension and Other Postretirement Benefit Plans Pension and Other Postretirement Benefit Plans
The Company has defined benefit pension plans covering eligible employees in the U.S. and in certain of its international subsidiaries. In addition, the Company provides medical benefits, principally to its eligible U.S. retirees and their dependents, through its other postretirement benefit plans. The Company uses December 31 as the year-end measurement date for all of its pension plans and other postretirement benefit plans.
Net Periodic Benefit Cost
The net periodic benefit cost (credit) for pension and other postretirement benefit plans consisted of the following components:
Pension Benefits
U.S.InternationalOther Postretirement Benefits
Years Ended December 31202420232022202420232022202420232022
Service cost$373 $326 $372 $243 $196 $283 $30 $32 $48 
Interest cost537 526 457 294 299 145 56 63 46 
Expected return on plan assets(826)(735)(753)(554)(517)(383)(80)(64)(86)
Amortization of unrecognized prior service (credit) cost
 (1)(32)(13)(14)(43)(49)(57)
Net loss (gain) amortization43 — 128 5 (3)96 (51)(42)(43)
Termination benefits5 1 — 4 — — 
Curtailments 12  (1)—  (1)(1)
Settlements 28 239 (1)(5) — — 
Net periodic benefit cost (credit)$132 $155 $425 $(25)$(29)$129 $(84)$(61)$(93)
In connection with restructuring actions (see Note 5), termination charges were recorded in 2024, 2023 and 2022 on pension and other postretirement benefit plans related to expanded eligibility for certain employees exiting Merck. Also, in connection with these restructuring activities, curtailments and settlements were recorded on certain pension plans. Lump sum payments to U.S. pension plan participants also contributed to the settlements recorded during 2023 and 2022.
The components of net periodic benefit cost (credit) other than the service cost component are included in Other (income) expense, net (see Note 14), with the exception of certain amounts for termination benefits, curtailments and settlements, which are recorded in Restructuring costs if the event giving rise to the termination benefits, curtailment or settlement is related to restructuring actions.
Obligations and Funded Status
Summarized information about the changes in plan assets and benefit obligations, the funded status and the amounts recorded at December 31 is as follows:

Pension BenefitsOther
Postretirement
Benefits
U.S.International
202420232024202320242023
Fair value of plan assets January 1$9,804 $9,094 $9,562 $8,473 $1,045 $947 
Actual return on plan assets266 1,077 637 832 35 115 
Company contributions262 307 198 249 46 74 
Effects of exchange rate changes — (522)283  — 
Benefits paid(615)(497)(250)(256)(89)(95)
Settlements (177)(14)(53) (2)
Other — 36 34 3 
Fair value of plan assets December 31$9,717 $9,804 $9,647 $9,562 $1,040 $1,045 
Benefit obligation January 1$10,446 $9,854 $9,042 $7,755 $1,104 $1,157 
Service cost373 326 243 196 30 32 
Interest cost537 526 294 299 56 63 
Actuarial (gains) losses (1)
(595)403 (549)766 32 (58)
Benefits paid(615)(497)(250)(256)(89)(95)
Effects of exchange rate changes — (473)288 (4)
Plan amendments — (56)14  — 
Curtailments  (1) — 
Termination benefits5 1 — 4 — 
Settlements (177)(14)(53) (2)
Other — 36 34 3 
Benefit obligation December 31$10,151 $10,446 $8,274 $9,042 $1,136 $1,104 
Funded status December 31$(434)$(642)$1,373 $520 $(96)$(59)
Recognized as:
Other Assets$26 $— $1,785 $1,019 $51 $107 
Accrued and other current liabilities(55)(49)(18)(19)(7)(8)
Other Noncurrent Liabilities(405)(593)(394)(480)(140)(158)
(1)    Actuarial (gains) losses primarily reflect changes in discount rates.
At December 31, 2024 and 2023, the accumulated benefit obligation was $18.1 billion and $19.1 billion, respectively, for all pension plans, of which $10.0 billion and $10.3 billion, respectively, related to U.S. pension plans.
Information related to the funded status of selected pension plans at December 31 is as follows:
U.S.International
2024202320242023
Pension plans with a projected benefit obligation in excess of plan assets
Projected benefit obligation
$9,517 $10,446 $1,847 $2,961 
Fair value of plan assets9,057 9,804 1,435 2,462 
Pension plans with an accumulated benefit obligation in excess of plan assets
Accumulated benefit obligation$442 $9,700 $1,768 $1,791 
Fair value of plan assets 9,186 1,385 1,336 
Plan Assets
Entities are required to use a fair value hierarchy which maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. There are three levels of inputs used to measure fair value with Level 1 having the highest priority and Level 3 having the lowest:
Level 1 — Quoted prices (unadjusted) in active markets for identical assets or liabilities.
Level 2 — Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3 — Unobservable inputs that are supported by little or no market activity. The Level 3 assets are those whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques with significant unobservable inputs, as well as instruments for which the determination of fair value requires significant judgment or estimation. At December 31, 2024 and 2023, $700 million and $788 million, respectively, or approximately 4% of the Company’s pension investments were categorized as Level 3 assets.
If the inputs used to measure the financial assets fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument.
The fair values of the Company’s pension plan assets at December 31 by asset category are as follows:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3
NAV (1)
TotalLevel 1Level 2Level 3
NAV (1)
Total
20242023
U.S. Pension Plans
Cash and cash equivalents$43 $ $ $121 $164 $34 $— $— $124 $158 
Investment funds
Developed markets equities170   2,385 2,555 224 — — 2,573 2,797 
Emerging markets equities   1,265 1,265 — — — 740 740 
Real estate   174 174 — — — 113 113 
Equity securities
Developed markets2,171    2,171 2,071 — — — 2,071 
Fixed income securities
Government and agency obligations 2,101   2,101 — 2,307 — — 2,307 
Corporate obligations 1,293   1,293 — 1,485 — — 1,485 
Mortgage and asset-backed securities 21   21 — 21 — — 21 
Other investments (liabilities)
Derivatives(29)   (29)109 — — — 109 
Other  2  2 — — — 
Plan assets at fair value$2,355 $3,415 $2 $3,945 $9,717 $2,438 $3,813 $$3,550 $9,804 
International Pension Plans
Cash and cash equivalents$112 $ $ $11 $123 $98 $— $— $20 $118 
Investment funds
Developed markets equities599 3,537  96 4,232 507 3,257 — 106 3,870 
Government and agency obligations262 2,974  149 3,385 234 3,123 — 166 3,523 
Corporate obligations23 8  149 180 23 — 166 197 
Emerging markets equities54   91 145 44 — — 66 110 
Other fixed income obligations8 7  4 19 — 20 
Real estate   12 12 — — — 10 10 
Equity securities
Developed markets287    287 278 — — — 278 
Fixed income securities
Government and agency obligations 368   368 — 423 — — 423 
Corporate obligations 141   141 — 160 — — 160 
Mortgage and asset-backed securities 54   54 — 61 — — 61 
Other investments
Insurance contracts (2)
 1 698 2 701 — 785 788 
Other     — — — 
Plan assets at fair value$1,345 $7,090 $698 $514 $9,647 $1,197 $7,041 $785 $539 $9,562 
(1)    Certain investments that were measured at net asset value (NAV) per share or its equivalent have not been classified in the fair value hierarchy. The NAV amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the fair value of plan assets at December 31, 2024 and 2023.
(2)    The plans’ Level 3 investments in insurance contracts are generally valued using a crediting rate that approximates market returns and invest in underlying securities whose market values are unobservable and determined using pricing models, discounted cash flow methodologies, or similar techniques.
The table below provides a summary of the changes in fair value, including transfers in and/or out, of all financial assets measured at fair value using significant unobservable inputs (Level 3) for the Company’s pension plan assets:
 20242023
Insurance
Contracts
OtherTotalInsurance
Contracts
OtherTotal
U.S. Pension Plans
Balance January 1$ $3 $3 $— $$
Actual return on plan assets:
Relating to assets still held at December 31 (2)(2)— (2)(2)
Relating to assets sold during the year 2 2 — 
Purchases and sales, net (1)(1)— (1)(1)
Balance December 31$ $2 $2 $— $$
International Pension Plans
Balance January 1$785 $ $785 $761 $— $761 
Actual return on plan assets:
Relating to assets still held at December 31(26) (26)77 — 77 
Purchases and sales, net(61) (61)(53)— (53)
Balance December 31$698 $ $698 $785 $— $785 
The fair values of the Company’s other postretirement benefit plan assets at December 31 by asset category are as follows:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3
NAV (1)
TotalLevel 1Level 2Level 3
NAV (1)
Total
20242023
Cash and cash equivalents$ $ $ $5 $5 $— $— $— $13 $13 
Investment funds
Developed markets equities3   46 49 24 — — 277 301 
Emerging markets equities   24 24 — — — 80 80 
Real estate   3 3 — — — 12 12 
Equity securities
Developed markets41   41 223 — — — 223 
Fixed income securities
Corporate obligations 598  598 — 157 — — 157 
Government and agency obligations 266  266 — 245 — — 245 
Mortgage and asset-backed securities 54   54 — — — 
Other Investments (liabilities)
Derivatives     12 — — — 12 
Plan assets at fair value$44 $918 $ $78 $1,040 $259 $404 $— $382 $1,045 
(1)    Certain investments that were measured at net asset value (NAV) per share or its equivalent have not been classified in the fair value hierarchy. The NAV amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the fair value of plan assets at December 31, 2024 and 2023.
The Company has established investment guidelines for its U.S. pension and other postretirement plans to create an asset allocation that is expected to deliver a rate of return sufficient to meet the long-term obligation of each plan, given an acceptable level of risk. The target investment portfolio of the Company’s U.S. pension and other postretirement benefit plans is allocated 25% to 40% in U.S. equities, 15% to 30% in international equities, 40% to 50% in fixed-income investments, and up to 8% in cash and other investments. The portfolio’s equity weighting is consistent with the long-term nature of the plans’ benefit obligations. The expected annual standard deviation of returns of the target portfolio, which approximates 12%, reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests. For international pension plans, the targeted investment portfolio varies based on the duration of pension liabilities and local government rules and regulations.
Although a significant percentage of plan assets are invested in U.S. equities, concentration risk is mitigated through the use of strategies that are diversified within management guidelines.
Expected Contributions
Contributions during 2025 are expected to be approximately $270 million for U.S. pension plans, approximately $180 million for international pension plans and approximately $70 million for other postretirement benefit plans.
Expected Benefit Payments
Expected benefit payments are as follows:
U.S. Pension BenefitsInternational Pension
Benefits
Other
Postretirement
Benefits
2025$771 $291 $86 
2026775 275 87 
2027789 286 89 
2028799 300 91 
2029822 314 96 
2030 — 2034
4,386 1,792 515 
Expected benefit payments are based on the same assumptions used to measure the benefit obligations and include estimated future employee service.
Amounts Recognized in Other Comprehensive Income (Loss)
Net gain/loss amounts reflect differences between expected and actual returns on plan assets as well as the effects of changes in actuarial assumptions. Net gain/loss amounts in excess of certain thresholds are amortized into net periodic benefit cost over the average remaining service life of employees. The following amounts were reflected as components of OCI:
 Pension PlansOther Postretirement
Benefit Plans
U.S.International
Years Ended December 31202420232022202420232022202420232022
Net gain (loss) arising during the period
$35 $(69)$(42)$634 $(438)$116 $(78)$110 $— 
Prior service credit (cost) arising during the period
 — — 56 (16)(4) — — 
 $35 $(69)$(42)$690 $(454)$112 $(78)$110 $— 
Net loss (gain) amortization included in benefit cost$43 $— $128 $5 $(3)$96 $(51)$(42)$(43)
Prior service (credit) cost amortization included in benefit cost
 (1)(32)(13)(14)(43)(49)(57)
Settlements and curtailments 36 251 (1)(6) (1)(1)
 $43 $35 $347 $(9)$(7)$83 $(94)$(92)$(101)
Actuarial Assumptions
The Company reassesses its benefit plan assumptions on a regular basis. The weighted average assumptions used in determining U.S. pension and other postretirement benefit plan and international pension plan information are as follows:
 U.S. Pension and Other
Postretirement Benefit Plans
International Pension Plans
December 31202420232022202420232022
Net periodic benefit cost      
Discount rate5.30 %5.50 %3.00 %3.40 %3.90 %1.50 %
Expected rate of return on plan assets7.75 %7.00 %6.70 %5.20 %5.00 %3.70 %
Salary growth rate4.60 %4.60 %4.60 %3.20 %3.20 %2.90 %
Interest crediting rate5.30 %5.30 %5.00 %3.40 %3.30 %3.00 %
Benefit obligation      
Discount rate5.70 %5.30 %5.50 %3.70 %3.40 %3.90 %
Salary growth rate4.80 %4.60 %4.60 %3.10 %3.20 %3.20 %
Interest crediting rate5.40 %5.30 %5.30 %3.50 %3.40 %3.30 %
For both the pension and other postretirement benefit plans, the discount rate is evaluated on measurement dates and modified to reflect the prevailing market rate of a portfolio of high-quality fixed-income debt instruments that would provide the future cash flows needed to pay the benefits included in the benefit obligation as they come due. The expected rate of return for both the pension and other postretirement benefit plans represents the average rate of return to be earned on plan assets over the period the benefits included in the benefit obligation are to be paid and is determined on a plan basis. The expected rate of return for each plan is developed considering long-term historical returns data, current market conditions, and actual returns on the plan assets. Using this reference information, the long-term return expectations for each asset category and a weighted-average expected return for each plan’s target portfolio is developed according to the allocation among those investment categories. The expected portfolio performance reflects the contribution of active management as appropriate. For 2025, the expected rate of return for the Company’s U.S. pension and other postretirement benefit plans will be 7.70%, as compared to 7.75% in 2024.
The health care cost trend rate assumptions for other postretirement benefit plans are as follows:
December 3120242023
Health care cost trend rate assumed for next year7.90 %7.80 %
Rate to which the cost trend rate is assumed to decline4.50 %4.50 %
Year that the trend rate reaches the ultimate trend rate20402038

Savings Plans
The Company also maintains defined contribution savings plans in the U.S. The Company matches a percentage of each employee’s contributions consistent with the provisions of the plan for which the employee is eligible. Total employer contributions to these plans in 2024, 2023 and 2022 were $215 million, $199 million and $175 million, respectively.
v3.25.0.1
Other (Income) Expense, Net
12 Months Ended
Dec. 31, 2024
Other Income and Expenses [Abstract]  
Other (Income) Expense, Net Other (Income) Expense, Net
Other (income) expense, net, consisted of:
Years Ended December 31202420232022
Interest income$(415)$(365)$(157)
Interest expense1,271 1,146 962 
Exchange losses227 370 237 
(Income) loss from investments in equity securities, net (1)
(14)(340)1,419 
Net periodic defined benefit plan (credit) cost other than service cost(633)(498)(279)
Other, net(460)153 (681)
 $(24)$466 $1,501 
(1)    Includes net realized and unrealized gains and losses from investments in equity securities either owned directly or through ownership interests in investment funds. Unrealized gains and losses from investments that are directly owned are determined at the end of the reporting period, while gains and losses from ownership interests in investment funds are accounted for on a one quarter lag.
Other, net (as reflected in the table above) in 2024 includes $170 million of income related to the expansion of a collaboration agreement with Daiichi Sankyo (see Note 4). Other, net, in 2023 includes a $572.5 million charge related to settlements with certain plaintiffs in the Zetia antitrust litigation (see Note 10).
Interest paid was $1.3 billion in 2024, $1.1 billion in 2023 and $937 million in 2022.
v3.25.0.1
Taxes on Income
12 Months Ended
Dec. 31, 2024
Income Tax Disclosure [Abstract]  
Taxes on Income Taxes on Income
A reconciliation between the effective tax rate and the U.S. statutory rate is as follows:
 202420232022
AmountTax RateAmountTax RateAmountTax Rate
U.S. statutory rate applied to income before taxes
$4,186 21.0 %$397 21.0 %$3,453 21.0 %
Differential arising from:
Foreign earnings(1,301)(6.5)(941)(49.8)(1,821)(11.1)
Tax settlements and statute lapses
(557)(2.8)— — (10)(0.1)
R&D tax credit(202)(1.0)(214)(11.3)(117)(0.7)
Inventory donations
(71)(0.4)(65)(3.5)(52)(0.3)
State taxes(39)(0.2)(117)(6.2)(110)(0.7)
Charges for certain research and development asset acquisitions
554 2.8 253 13.4 — — 
Valuation allowances54 0.3 70 3.7 108 0.7 
Restructuring52 0.3 41 2.2 11 0.1 
GILTI and the foreign-derived intangible income deduction29 0.1 (80)(4.3)462 2.8 
Acquisition-related costs, including amortization
18 0.1 42 2.2 (3)— 
Acquisition of Prometheus
  2,139 113.3 — — 
Other80 0.4 (13)(0.7)(3)— 
 $2,803 14.1 %$1,512 80.0 %$1,918 11.7 %
Where applicable, the impact of changes in uncertain tax positions is reflected in the reconciling items above.
The Company’s remaining transition tax liability under the Tax Cuts and Jobs Act (TCJA) of 2017, which has been reduced by payments and the expected utilization of foreign tax credits, was a net liability of $518 million at December 31, 2024, which is comprised of a $1.2 billion tax liability included in Income taxes payable, offset by $702 million of foreign tax credits included in Other Assets that Merck expects to be applied upon the completion of the IRS’s examination of the Company’s tax returns for the 2017 and 2018 federal tax years. As a result of the transition tax under the TCJA, the Company is no longer indefinitely reinvested with respect to its undistributed earnings from foreign subsidiaries and has provided a deferred tax liability for foreign withholding taxes that would apply. The
Company remains indefinitely reinvested with respect to its financial statement basis in excess of tax basis of its foreign subsidiaries. A determination of the net deferred tax liability with respect to this basis difference is not practicable.
The foreign earnings tax rate differentials in the tax rate reconciliation above primarily reflect the impacts of operations in jurisdictions with different effective tax rates than the U.S., particularly Ireland, the Netherlands and Switzerland, as well as Singapore and Puerto Rico which operate under tax incentive grants (which begin to expire in 2025), thereby yielding a favorable impact on the effective tax rate compared with the U.S. statutory rate of 21%. The Company has an additional Cantonal tax holiday in Switzerland that provides for a tax rate reduction and is effective through 2032. The Company’s income that is subject to tax incentive grants and the Cantonal tax holiday in Switzerland is subject to the global minimum tax provision of the Organization for Economic Cooperation and Development (OECD) Pillar 2, effective in 2024.
Income before taxes consisted of:
Years Ended December 31202420232022
Domestic$(1,849)$(15,622)$1,011 
Foreign21,785 17,511 15,433 
 $19,936 $1,889 $16,444 
Taxes on income consisted of:
Years Ended December 31202420232022
Current provision
Federal$944 $928 $2,265 
Foreign3,123 2,435 1,164 
State(15)48 57 
 4,052 3,411 3,486 
Deferred provision
Federal(1,475)(1,559)(1,510)
Foreign212 (233)71 
State14 (107)(129)
 (1,249)(1,899)(1,568)
 $2,803 $1,512 $1,918 
Deferred income taxes at December 31 consisted of:
 20242023
AssetsLiabilitiesAssetsLiabilities
Product intangibles and licenses$71 $978 $— $1,308 
R&D capitalization3,062  2,099 — 
Inventory related84 413 86 370 
Accelerated depreciation 645 — 626 
Undistributed foreign earnings
275 371 76 118 
Equity investments 90 — 73 
Pensions and other postretirement benefits224 400 323 249 
Compensation related400  357 — 
Unrecognized tax benefits152  147 — 
Net operating losses and other tax credit carryforwards910  868 — 
Other802 159 755 214 
Subtotal5,980 3,056 4,711 2,958 
Valuation allowance(710) (656) 
Total deferred taxes$5,270 $3,056 $4,055 $2,958 
Net deferred income taxes$2,214 $1,097 
Recognized as:
Other Assets$3,601 $1,968 
Deferred Income Taxes $1,387  $871 
The Company has net operating loss (NOL) carryforwards in several jurisdictions. As of December 31, 2024, $324 million of deferred tax assets on NOL carryforwards relate to foreign jurisdictions. Valuation allowances of $264 million have been established on these foreign NOL carryforwards and other foreign deferred tax assets. In addition, the Company has $586 million of deferred tax assets relating to various U.S. tax credit carryforwards and NOL carryforwards. Valuation allowances of $446 million have been established on these U.S. tax credit carryforwards and NOL carryforwards.
Income taxes paid in 2024, 2023 and 2022 consisted of:
Years Ended December 31202420232022
Domestic (1)
$974 $2,258 $1,891 
Foreign2,954 2,080 1,348 
 $3,928 $4,338 $3,239 
(1)    Includes TCJA transition tax payments.
Tax benefits relating to stock option exercises were $26 million in 2024, $12 million in 2023 and $45 million in 2022.
A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
202420232022
Balance January 1$2,384 $1,835 $1,529 
Additions related to current year positions421 553 344 
Additions related to prior year positions35 91 48 
Reductions for tax positions of prior years
(33)(20)(40)
Settlements
(18)(23)(6)
Lapse of statute of limitations (1)
(528)(52)(40)
Balance December 31$2,261 $2,384 $1,835 
(1)    Amount in 2024 reflects a reduction of $451 million resulting from the expiration of the statute of limitations related to the 2019 and 2020 federal tax return years.
If the Company were to recognize the unrecognized tax benefits of $2.3 billion at December 31, 2024, the income tax provision would reflect a favorable net impact of $2.2 billion.
The Company is under examination by numerous tax authorities in various jurisdictions globally. The Company believes that it is reasonably possible that the total amount of unrecognized tax benefits as of December 31, 2024 could decrease by up to approximately $22 million in the next 12 months as a result of various audit closures, settlements or the expiration of the statute of limitations. The ultimate finalization of the Company’s examinations with relevant taxing authorities can include formal administrative and legal proceedings, which could have a significant impact on the timing of the reversal of unrecognized tax benefits. The Company believes that its reserves for uncertain tax positions are adequate to cover existing risks or exposures.
Interest and penalties associated with uncertain tax positions amounted to an expense of $51 million in 2024, $131 million in 2023 and $54 million in 2022. These amounts reflect the beneficial impacts of various tax settlements. Liabilities for accrued interest and penalties were $437 million and $388 million as of December 31, 2024 and 2023, respectively.
In 2024, the Company recorded a benefit of $519 million due to a reduction in reserves for unrecognized income tax benefits resulting from the expiration in 2024 of the statute of limitations for assessments related to the 2019 and 2020 federal tax return years. The Internal Revenue Service (IRS) is currently conducting examinations of the Company’s tax returns for the years 2017 and 2018, including the one-time transition tax enacted under the TCJA. If the IRS disagrees with the Company’s transition tax position, it may result in a significant tax liability. The IRS is also currently conducting examinations of the Company’s tax returns for the years 2021 and 2022. In addition, various state and foreign tax examinations are in progress and for these jurisdictions, the Company’s income tax returns are open for examination for the period 2009 through 2024.
v3.25.0.1
Earnings per Share
12 Months Ended
Dec. 31, 2024
Earnings Per Share [Abstract]  
Earnings per Share Earnings per Share
The calculations of earnings per share (shares in millions) are as follows:
Years Ended December 31202420232022
Net Income Attributable to Merck & Co., Inc.$17,117 $365 $14,519 
Average common shares outstanding2,532 2,537 2,532 
Common shares issuable (1)
9 10 10 
Average common shares outstanding assuming dilution2,541 2,547 2,542 
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders
$6.76 $0.14 $5.73 
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders
$6.74 $0.14 $5.71 
(1)     Issuable primarily under share-based compensation plans.
In 2024, 2023 and 2022, 6 million, 5 million and 2 million, respectively, of common shares issuable under share-based compensation plans were excluded from the computation of earnings per common share assuming dilution because the effect would have been antidilutive.
v3.25.0.1
Other Comprehensive Income (Loss)
12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Other Comprehensive Income (Loss) Other Comprehensive Income (Loss)
Changes in each component of other comprehensive income (loss) are as follows:
DerivativesEmployee
Benefit
Plans
 Foreign Currency
Translation
Adjustment
Accumulated Other
Comprehensive Loss
Balance at January 1, 2022, net of taxes
$144 $(2,743)$(1,830)$(4,429)
Other comprehensive income (loss) before reclassification adjustments, pretax684 70 (584)170 
Tax(143)12 (19)(150)
Other comprehensive income (loss) before reclassification adjustments, net of taxes541 82 (603)20 
Reclassification adjustments, pretax(775)
(1)
329 
(2)
— (446)
Tax163 (76)— 87 
Reclassification adjustments, net of taxes(612)253 — (359)
Other comprehensive income (loss), net of taxes(71)335 (603)(339)
Balance at December 31, 2022, net of taxes73 (2,408)(2,433)(4,768)
Other comprehensive income (loss) before reclassification adjustments, pretax114 (413)17 (282)
Tax(24)86 63 125 
Other comprehensive income (loss) before reclassification adjustments, net of taxes90 (327)80 (157)
Reclassification adjustments, pretax(237)
(1)
(64)
(2)
(292)
Tax50 — 56 
Reclassification adjustments, net of taxes(187)(58)(236)
Other comprehensive income (loss), net of taxes(97)(385)89 (393)
Balance at December 31, 2023, net of taxes(24)(2,793)
(3)
(2,344)(5,161)
Other comprehensive income (loss) before reclassification adjustments, pretax508 647 (559)596 
Tax(109)(138)23 (224)
Other comprehensive income (loss) before reclassification adjustments, net of taxes399 509 (536)372 
Reclassification adjustments, pretax(168)
(1)
(60)
(2)
20 (208)
Tax35 17  52 
Reclassification adjustments, net of taxes(133)(43)20 (156)
Other comprehensive income (loss), net of taxes266 466 (516)216 
Balance at December 31, 2024, net of taxes$242 $(2,327)
(3)
$(2,860)$(4,945)
(1)    Primarily relates to foreign currency cash flow hedges that were reclassified from AOCL to Sales (see Note 6).
(2)    Includes net amortization of prior service cost, actuarial gains and losses, settlements and curtailments included in net periodic benefit cost (see Note 13).
(3)    Includes pension plan net loss of $3.0 billion and $3.5 billion at December 31, 2024 and 2023, respectively, and other postretirement benefit plan net gain of $400 million and $500 million at December 31, 2024 and 2023, respectively, as well as pension plan prior service credit of $174 million and $141 million at December 31, 2024 and 2023, respectively, and other postretirement benefit plan prior service credit of $61 million and $95 million at December 31, 2024 and 2023, respectively.
v3.25.0.1
Segment Reporting
12 Months Ended
Dec. 31, 2024
Segment Reporting [Abstract]  
Segment Reporting Segment Reporting
The Company’s operations are principally managed on a product basis and include two operating segments, Pharmaceutical and Animal Health, both of which are reportable segments.
The Pharmaceutical segment includes human health pharmaceutical and vaccine products. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Human health vaccine products consist of preventive pediatric, adolescent and adult vaccines. The Company sells these human health vaccines primarily to physicians, wholesalers, distributors and government entities. A large component of pediatric and adolescent vaccine sales are made to the U.S. Centers for Disease Control and Prevention Vaccines for Children program, which is funded by the U.S. government. Additionally, the Company sells vaccines to the Federal government for placement into vaccine stockpiles.
The Animal Health segment discovers, develops, manufactures and markets a wide range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment and control of disease in all major livestock and companion animal species. The Company also offers an extensive suite of digitally connected identification, traceability and monitoring products. The Company sells its products to veterinarians, distributors, animal producers, farmers and pet owners.
Sales of the Company’s products were as follows:
Years Ended December 31202420232022
U.S.Int’lTotalU.S.Int’lTotalU.S.Int’lTotal
Pharmaceutical:
Oncology
Keytruda$17,872 $11,610 $29,482 $15,114 $9,897 $25,011 $12,686 $8,251 $20,937 
Alliance revenue - Lynparza (1)
626 685 1,311 607 592 1,199 584 532 1,116 
Alliance revenue - Lenvima (1)
705 305 1,010 657 303 960 579 297 876 
Welireg466 43 509 209 10 218 123 — 123 
Alliance revenue - Reblozyl (2)
303 68 371 168 43 212 123 43 166 
Vaccines
Gardasil/Gardasil 9
2,425 6,158 8,583 2,083 6,803 8,886 2,065 4,832 6,897 
ProQuad/M-M-R II/Varivax1,919 566 2,485 1,837 531 2,368 1,724 518 2,241 
Vaxneuvance461 347 808 561 103 665 163 170 
RotaTeq472 239 711 493 276 769 508 275 783 
Pneumovax 23
56 207 263 127 285 412 346 256 602 
Hospital Acute Care
Bridion1,401 363 1,764 1,156 686 1,842 922 762 1,685 
Prevymis371 414 785 264 341 605 188 240 428 
Dificid303 37 340 274 28 302 241 22 263 
Zerbaxa146 106 252 119 100 218 89 79 169 
Noxafil7 170 177 32 181 213 51 187 238 
Cardiovascular
Winrevair
408 11 419 — — — — — — 
Alliance revenue - Adempas/Verquvo (3)
388 27 415 350 16 367 329 12 341 
Adempas 287 287 — 255 255 — 238 238 
Virology
Lagevrio176 787 964 10 1,418 1,428 1,523 4,161 5,684 
Isentress/Isentress HD185 209 394 215 268 483 274 359 633 
Delstrigo
56 193 249 49 152 201 39 111 151 
Pifeltro
113 50 163 101 41 142 87 30 118 
Neuroscience
Belsomra72 150 222 81 150 231 79 179 258 
Immunology
Simponi 543 543 — 710 710 — 706 706 
Remicade 114 114 — 187 187 — 207 207 
Diabetes
Januvia469 865 1,334 1,151 1,039 2,189 1,248 1,565 2,813 
Janumet161 774 935 223 954 1,177 355 1,344 1,700 
Other pharmaceutical (4)
729 1,782 2,510 658 1,675 2,333 663 1,803 2,462 
Total Pharmaceutical segment sales30,290 27,110 57,400 26,539 27,044 53,583 24,989 27,016 52,005 
Animal Health:
Livestock732 2,729 3,462 700 2,637 3,337 710 2,590 3,300 
Companion Animal1,129 1,287 2,415 1,104 1,184 2,288 1,112 1,138 2,250 
Total Animal Health segment sales1,861 4,016 5,877 1,804 3,821 5,625 1,822 3,728 5,550 
Total segment sales32,151 31,126 63,277 28,343 30,865 59,208 26,811 30,744 57,555 
Other (5)
126 765 891 137 770 907 395 1,333 1,728 
 $32,277 $31,891 $64,168 $28,480 $31,635 $60,115 $27,206 $32,077 $59,283 
U.S. plus international may not equal total due to rounding.
(1)    Alliance revenue for Lynparza and Lenvima represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 4).
(2)    Alliance revenue for Reblozyl represents royalties and, for 2022, also includes a payment received related to the achievement of a regulatory approval milestone (see Note 4).
(3)    Alliance revenue for Adempas/Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 4).
(4)    Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately.
(5)    Other is primarily comprised of miscellaneous corporate revenue, including revenue hedging activities which increased sales by $195 million, $244 million and $810 million in 2024, 2023 and 2022, respectively, as well as revenue from third-party manufacturing arrangements (including sales to Organon). Other for 2024, 2023 and 2022 also includes $106 million, $118 million and $165 million, respectively, related to upfront and milestone payments received by Merck for out-licensing arrangements.
Consolidated sales by geographic area where derived are as follows:
Years Ended December 31202420232022
United States$32,277 $28,480 $27,206 
Europe, Middle East and Africa14,041 13,254 14,493 
China5,494 6,802 5,191 
Latin America3,459 3,086 2,582 
Japan3,280 3,164 3,629 
Asia Pacific (other than China and Japan)3,058 3,225 3,614 
Other2,559 2,104 2,568 
 $64,168 $60,115 $59,283 
A reconciliation of segment profits to Income Before Taxes is as follows:
Years Ended December 31202420232022
Pharma-ceutical
Animal Health
Total
Pharma-ceutical
Animal Health
Total
Pharma-ceutical
Animal Health
Total
Segment sales
$57,400 $5,877 $63,277 $53,583 $5,625 $59,208 $52,005 $5,550 $57,555 
Less segment costs: (1)
Cost of sales
6,828 2,469 8,849 2,498 9,678 2,259 
Selling, general and administrative
6,128 1,084 5,903 1,038 5,474 999 
Research and development (2)
 385 — 353 — 329 
Other segment items (3)
(89)1 (49)(1)— 
Total segment profits44,533 1,938 46,471 38,880 1,737 40,617 36,852 1,963 38,815 
Other profits492 474 1,160 
Unallocated:
Interest income415 365 157 
Interest expense(1,271)(1,146)(962)
Amortization(2,395)(2,044)(2,085)
Depreciation(1,843)(1,625)(1,642)
Research and development(17,350)(30,008)(13,011)
Restructuring costs(309)(599)(337)
Charge for Zetia antitrust litigation settlements (573)— 
Other unallocated, net(4,274)(3,572)(5,651)
$19,936 $1,889 $16,444 
(1)    The significant expense categories and amounts align with the segment level information that is regularly provided to the chief operating decision maker.
(2)    Human health-related research and development expenses incurred by Merck Research Laboratories are not allocated to segment profits as noted below.
(3)    Includes equity (income) loss from affiliates and other miscellaneous non-operating expenses.

Pharmaceutical segment profits are comprised of segment sales less standard costs, as well as selling, general and administrative expenses directly incurred by the segment. Animal Health segment profits are comprised of segment sales, less all cost of sales, as well as selling, general and administrative expenses and research and development costs directly incurred by the segment. The chief operating decision maker (Merck’s Chief Executive Officer) uses segment profit to allocate resources predominately during the planning and forecasting process. For internal management reporting presented to the chief operating decision maker, Merck does not allocate the remaining cost of sales not included in segment profits as described above, research and development expenses incurred by Merck Research Laboratories, the Company’s research and development division that focuses on human health-related activities, or general and administrative expenses not directly incurred by the segments, nor the cost of financing these activities. Separate divisions maintain responsibility for monitoring and managing these costs, including depreciation related to fixed assets utilized by these divisions and, therefore, they are not included in segment profits. In addition, costs related to restructuring activities, as well as the amortization of intangible assets and amortization of purchase accounting adjustments are not allocated to segments.
Other profits are primarily comprised of miscellaneous corporate profits, as well as operating profits (losses) related to third-party manufacturing arrangements.
Other unallocated, net, includes expenses from corporate and manufacturing cost centers, intangible asset impairment charges, gains or losses on sales of businesses, expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration, and other miscellaneous income or expense items.
Equity income from affiliates and depreciation included in segment profits is as follows:
PharmaceuticalAnimal HealthTotal
Year Ended December 31, 2024
Equity income from affiliates$144 $ $144 
Depreciation5 256 261 
Year Ended December 31, 2023
Equity income from affiliates$111 $— $111 
Depreciation198 203 
Year Ended December 31, 2022
Equity income from affiliates
$39 $— $39 
Depreciation177 182 
Property, plant and equipment, net, by geographic area where located is as follows:
December 31202420232022
United States$14,724 $13,915 $12,891 
Europe, Middle East and Africa7,548 7,562 6,993 
Asia Pacific (other than China and Japan)982 1,022 966 
China202 193 207 
Japan143 133 135 
Latin America133 222 225 
Other47 
 $23,779 $23,051 $21,422 
The Company does not disaggregate assets on a products and services basis for internal management reporting and, therefore, such information is not presented.
v3.25.0.1
Pay vs Performance Disclosure - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Pay vs Performance Disclosure      
Net Income Attributable to Merck & Co., Inc. $ 17,117 $ 365 $ 14,519
v3.25.0.1
Insider Trading Arrangements
3 Months Ended
Dec. 31, 2024
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.25.0.1
Insider Trading Policies and Procedures
12 Months Ended
Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]  
Insider Trading Policies and Procedures Adopted true
v3.25.0.1
Cybersecurity Risk Management and Strategy Disclosure
12 Months Ended
Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]  
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]
The Company’s cybersecurity measures are primarily focused on ensuring the security and protection of its IT systems and data. The Company’s information security program is managed by a dedicated Chief Information Security Officer (CISO), whose group is responsible for leading enterprise-wide cybersecurity risk management, strategy, policy, standards, architecture, and processes. The CISO has worked in the cybersecurity and national security fields for more than 30 years. He has a Master of Science in Telecommunications and Computers. He has served as a board member of the Health Information Sharing and Analysis Center for 10 years. Oversight of the information security program has been integrated into the Company’s overall enterprise risk management program.
The CISO provides periodic reports to the Audit Committee (Audit Committee) of the Board of Directors (Board), the full Board, as well as to the Company’s Chief Executive Officer and other members of senior management, as appropriate. These reports include updates on the Company’s cybersecurity risks and threats, the status of projects intended to strengthen its information security systems, assessments of the information security program (including remediation, mitigation, and management of identified vulnerabilities), and the emerging threat landscape. The information security program is regularly evaluated by internal and external consultants and auditors with the results of those reviews reported to senior management and the Audit Committee, which is comprised entirely of independent directors and has oversight responsibility for these risks.
The Company’s information security group monitors the Company’s information systems to prevent, detect, mitigate, and remediate cybersecurity incidents. The Company uses tools and techniques to continually assess and monitor, manage and mitigate cybersecurity threats to its IT systems in a manner consistent with industry practice. The Company engages with key vendors, industry participants, and intelligence and law enforcement communities as part of its continuing efforts to obtain current threat intelligence, collaborate on security enhancements, and evaluate and improve the effectiveness of its information security program. As part of this program, the Company conducts periodic tabletop and red-teaming exercises to assess its cybersecurity incident response processes and defenses. The Company also maintains vendor management diligence and oversight processes to identify and monitor potential risks from cybersecurity threats attendant to its use of third-party service providers. Additionally, the Company monitors cybersecurity threat intelligence received from key third-party service providers associated with the Company.
Cybersecurity Risk Management Processes Integrated [Flag] true
Cybersecurity Risk Management Processes Integrated [Text Block]
The Company’s cybersecurity measures are primarily focused on ensuring the security and protection of its IT systems and data. The Company’s information security program is managed by a dedicated Chief Information Security Officer (CISO), whose group is responsible for leading enterprise-wide cybersecurity risk management, strategy, policy, standards, architecture, and processes. The CISO has worked in the cybersecurity and national security fields for more than 30 years. He has a Master of Science in Telecommunications and Computers. He has served as a board member of the Health Information Sharing and Analysis Center for 10 years. Oversight of the information security program has been integrated into the Company’s overall enterprise risk management program.
Cybersecurity Risk Management Third Party Engaged [Flag] true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag] true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag] false
Cybersecurity Risk Board of Directors Oversight [Text Block] The CISO provides periodic reports to the Audit Committee (Audit Committee) of the Board of Directors (Board), the full Board, as well as to the Company’s Chief Executive Officer and other members of senior management, as appropriate. These reports include updates on the Company’s cybersecurity risks and threats, the status of projects intended to strengthen its information security systems, assessments of the information security program (including remediation, mitigation, and management of identified vulnerabilities), and the emerging threat landscape. The information security program is regularly evaluated by internal and external consultants and auditors with the results of those reviews reported to senior management and the Audit Committee, which is comprised entirely of independent directors and has oversight responsibility for these risks.
In the event of a cybersecurity incident, the Company has a process in place whereby members of the information security group will alert the CISO and the CISO will alert the appropriate levels of management, including an incident assessment team, as well as the legal and finance departments so that the materiality of any such event can be assessed in furtherance of fulfilling any reporting requirements. If warranted, senior management will notify the Audit Committee or the full Board, as appropriate.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block] The information security program is regularly evaluated by internal and external consultants and auditors with the results of those reviews reported to senior management and the Audit Committee, which is comprised entirely of independent directors and has oversight responsibility for these risks.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block] The CISO provides periodic reports to the Audit Committee (Audit Committee) of the Board of Directors (Board), the full Board, as well as to the Company’s Chief Executive Officer and other members of senior management, as appropriate. These reports include updates on the Company’s cybersecurity risks and threats, the status of projects intended to strengthen its information security systems, assessments of the information security program (including remediation, mitigation, and management of identified vulnerabilities), and the emerging threat landscape. The information security program is regularly evaluated by internal and external consultants and auditors with the results of those reviews reported to senior management and the Audit Committee, which is comprised entirely of independent directors and has oversight responsibility for these risks.
In the event of a cybersecurity incident, the Company has a process in place whereby members of the information security group will alert the CISO and the CISO will alert the appropriate levels of management, including an incident assessment team, as well as the legal and finance departments so that the materiality of any such event can be assessed in furtherance of fulfilling any reporting requirements. If warranted, senior management will notify the Audit Committee or the full Board, as appropriate.
Cybersecurity Risk Role of Management [Text Block]
The Company’s cybersecurity measures are primarily focused on ensuring the security and protection of its IT systems and data. The Company’s information security program is managed by a dedicated Chief Information Security Officer (CISO), whose group is responsible for leading enterprise-wide cybersecurity risk management, strategy, policy, standards, architecture, and processes. The CISO has worked in the cybersecurity and national security fields for more than 30 years. He has a Master of Science in Telecommunications and Computers. He has served as a board member of the Health Information Sharing and Analysis Center for 10 years. Oversight of the information security program has been integrated into the Company’s overall enterprise risk management program.
In the event of a cybersecurity incident, the Company has a process in place whereby members of the information security group will alert the CISO and the CISO will alert the appropriate levels of management, including an incident assessment team, as well as the legal and finance departments so that the materiality of any such event can be assessed in furtherance of fulfilling any reporting requirements. If warranted, senior management will notify the Audit Committee or the full Board, as appropriate.
Cybersecurity Risk Management Positions or Committees Responsible [Flag] true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block] The Company’s information security program is managed by a dedicated Chief Information Security Officer (CISO), whose group is responsible for leading enterprise-wide cybersecurity risk management, strategy, policy, standards, architecture, and processes.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block] The CISO has worked in the cybersecurity and national security fields for more than 30 years. He has a Master of Science in Telecommunications and Computers. He has served as a board member of the Health Information Sharing and Analysis Center for 10 years.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]
The CISO provides periodic reports to the Audit Committee (Audit Committee) of the Board of Directors (Board), the full Board, as well as to the Company’s Chief Executive Officer and other members of senior management, as appropriate. These reports include updates on the Company’s cybersecurity risks and threats, the status of projects intended to strengthen its information security systems, assessments of the information security program (including remediation, mitigation, and management of identified vulnerabilities), and the emerging threat landscape. The information security program is regularly evaluated by internal and external consultants and auditors with the results of those reviews reported to senior management and the Audit Committee, which is comprised entirely of independent directors and has oversight responsibility for these risks.
In the event of a cybersecurity incident, the Company has a process in place whereby members of the information security group will alert the CISO and the CISO will alert the appropriate levels of management, including an incident assessment team, as well as the legal and finance departments so that the materiality of any such event can be assessed in furtherance of fulfilling any reporting requirements. If warranted, senior management will notify the Audit Committee or the full Board, as appropriate.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag] true
v3.25.0.1
Summary of Accounting Policies (Policies)
12 Months Ended
Dec. 31, 2024
Accounting Policies [Abstract]  
Principles of Consolidation
Principles of Consolidation — The consolidated financial statements include the accounts of the Company and all of its subsidiaries in which a controlling interest is maintained. Intercompany balances and transactions are eliminated. Controlling interest is determined by majority ownership interest and the absence of substantive third-party participating rights or, in the case of variable interest entities, by majority exposure to expected losses, residual returns or both. For those consolidated subsidiaries where Merck ownership is less than 100%, the outside shareholders’ interests are shown as Noncontrolling interests in equity. Investments in affiliates over which the Company has significant influence but not a controlling interest, such as interests in entities owned equally by the Company and a third party that are under shared control, are carried on the equity method basis.
Acquisitions
Acquisitions — In a business combination, the acquisition method of accounting requires that the assets acquired and liabilities assumed be recorded as of the date of the acquisition at their respective fair values with limited exceptions. Assets acquired and liabilities assumed in a business combination that arise from contingencies are generally recognized at fair value. If fair value cannot be determined, the asset or liability is recognized if probable and reasonably estimable; if these criteria are not met, no asset or liability is recognized. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Accordingly, the Company may be required to value assets at fair value measures that do not reflect the Company’s intended use of those assets. Any excess of the purchase price (consideration transferred) over the estimated fair values of net assets acquired is recorded as goodwill. Transaction costs and costs to restructure the acquired company are expensed as incurred. The operating results of the acquired business are reflected in the Company’s consolidated financial statements after the date of the acquisition.
If the Company determines the assets acquired do not meet the definition of a business under the acquisition method of accounting, the transaction will be accounted for as an acquisition of assets rather than a business combination and, therefore, no goodwill will be recorded. In an asset acquisition, acquired in-process research and development (IPR&D) with no alternative future use is charged to expense and contingent consideration is not recognized at the acquisition date.
Foreign Currency Translation
Foreign Currency Translation — The net assets of international subsidiaries where the local currencies have been determined to be the functional currencies are translated into U.S. dollars using current exchange rates and results of operations are translated at average exchange rates. The U.S. dollar effects that arise from translating the net assets of these subsidiaries at changing rates are recorded in Other Comprehensive Income (OCI) and remain in Accumulated other comprehensive loss (AOCL) until either the sale or complete or substantially complete liquidation of the subsidiary. For those subsidiaries that operate in highly inflationary economies and for those subsidiaries where the U.S. dollar has been determined to be the functional currency, non-monetary foreign currency
assets and liabilities are translated using historical rates, while monetary assets and liabilities are translated at current rates, with the U.S. dollar effects of rate changes included in Other (income) expense, net.
Cash Equivalents
Cash Equivalents — Cash equivalents are comprised of certain highly liquid investments with original maturities of less than three months.
Inventories
Inventories — Inventories are valued at the lower of cost or net realizable value. The cost of a substantial majority of U.S. human health inventories is determined using the last-in, first-out (LIFO) method for both financial reporting and tax purposes. The cost of all other inventories is determined using the first-in, first-out (FIFO) method. Inventories consist of currently marketed products, as well as certain inventories produced in preparation for product launches that are considered by the Company to be probable of obtaining regulatory approval. In evaluating the recoverability of inventories produced in preparation for product launches, the Company considers the likelihood that revenue will be obtained from the future sale of the related inventory together with the status of the product during the research and regulatory approval process.
Investments
Investments — Investments in marketable debt securities classified as available-for-sale are reported at fair value. Fair values of the Company’s investments in marketable debt securities are determined using quoted market prices in active markets for identical assets or quoted prices for similar assets or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Changes in fair value that are not impairment related are reported net of taxes in OCI. The Company considers available evidence in evaluating potential impairments of its investments in marketable debt securities, including the extent to which fair value is less than cost, whether an allowance for credit loss is required, as well as adverse factors that could affect the value of the securities. An impairment has occurred if the Company does not expect to recover the entire amortized cost basis of the marketable debt security. If the Company does not intend to sell the impaired debt security, and it is not more likely than not it will be required to sell the debt security before the recovery of its amortized cost basis, the amount of the impairment recognized in earnings, recorded in Other (income) expense, net, is limited to the portion attributed to credit loss. The remaining portion of the impairment related to other factors is recognized in OCI. Realized gains and losses for debt securities are included in Other (income) expense, net.
Investments in publicly traded equity securities are reported at fair value as determined using quoted market prices in active markets for identical assets or quoted prices for similar assets or other inputs that are observable or can be corroborated by observable market data. Changes in fair value are included in Other (income) expense, net. Unrealized gains and losses from investments that are directly owned are determined at the end of the reporting period. Gains and losses from ownership interests in investment funds, which are accounted for as equity method investments, are reported on a one quarter lag. Investments in equity securities without readily determinable fair values are recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, minus impairments. Such adjustments are recognized in Other (income) expense, net. Realized gains and losses for equity securities are included in Other (income) expense, net.
Revenue Recognition
Revenue Recognition — Recognition of revenue requires evidence of a contract, probable collection of sales proceeds and completion of substantially all performance obligations. Merck acts as the principal in substantially all of its customer arrangements and therefore records revenue on a gross basis. The majority of the Company’s contracts related to the Pharmaceutical and Animal Health segments have a single performance obligation - the promise to transfer goods. Shipping is considered immaterial in the context of the overall customer arrangement and damages or loss of goods in transit are rare. Therefore, shipping is not deemed a separately recognized performance obligation.
The vast majority of revenues from sales of products are recognized at a point in time when control of the goods is transferred to the customer, which the Company has determined is when title and risks and rewards of ownership transfer to the customer and the Company is entitled to payment. The Company recognizes revenue from the sales of vaccines to the U.S. federal government for placement into vaccine stockpiles in accordance with Securities and Exchange Commission (SEC) Interpretation, Commission Guidance Regarding Accounting for Sales of Vaccines and BioTerror Countermeasures to the Federal Government for Placement into the Pediatric Vaccine Stockpile or the Strategic National Stockpile. This interpretation allows companies to recognize revenue for sales of vaccines into U.S. government stockpiles even though these sales might not meet the criteria for revenue recognition under other accounting guidance. For certain services in the Animal Health segment, revenue is recognized over time, generally ratably over the contract term as services are provided. These service revenues are not material.
The nature of the Company’s business gives rise to several types of variable consideration including discounts and returns, which are estimated at the time of sale generally using the expected value method, although the most likely amount method is used for prompt pay discounts.
In the U.S., sales discounts are issued to customers at the point-of-sale, through an intermediary wholesaler (known as chargebacks), or in the form of rebates. Additionally, sales are generally made with a limited right of return under certain conditions. Revenues are recorded net of provisions for sales discounts and returns, which are established at the time of sale. In addition, if collection of accounts receivable is expected to be in excess of one year, sales are recorded net of time value of money discounts, which have not been material.
The U.S. provision for aggregate customer discounts covering chargebacks and rebates was $13.3 billion in 2024, $12.5 billion in 2023 and $12.3 billion in 2022. Chargebacks are discounts that occur when a contracted customer purchases through an intermediary wholesaler. The wholesaler then charges the Company back for the difference between the price initially paid by the wholesaler and the contract price agreed to between Merck and the customer. The provision for chargebacks is based on expected sell-through levels by the Company’s wholesale customers to contracted customers, as well as estimated wholesaler inventory levels. Rebates are amounts owed based upon definitive contractual agreements or legal requirements with private sector and public sector (Medicaid and Medicare Part D) benefit providers after the final dispensing of the product to a benefit plan participant. The provision for rebates is based on expected patient usage, as well as inventory levels in the distribution channel to determine the contractual obligation to the benefit providers. The Company uses historical customer segment utilization mix, sales forecasts, changes to product mix and price, inventory levels in the distribution channel, government pricing calculations and prior payment history in order to estimate the expected provision. Amounts accrued for aggregate customer discounts are evaluated on a quarterly basis through comparison of information provided by the wholesalers, health maintenance organizations, pharmacy benefit managers, federal and state agencies, and other customers to the amounts accrued. The accrued balances relative to the provisions for chargebacks and rebates included in Accounts receivable and Accrued and other current liabilities were $293 million and $2.2 billion, respectively, at December 31, 2024 and were $188 million and $2.3 billion, respectively, at December 31, 2023.
Outside of the U.S., variable consideration in the form of discounts and rebates are a combination of commercially-driven discounts in highly competitive product classes, discounts required to gain or maintain reimbursement, or legislatively mandated rebates. In certain European countries, legislatively mandated rebates are calculated based on an estimate of the government’s total unbudgeted spending and the Company’s specific payback obligation. Rebates may also be required based on specific product sales thresholds. The Company applies an estimated factor against its actual invoiced sales to represent the expected level of future discount or rebate obligations associated with the sale.
The Company maintains a returns policy that allows its U.S. pharmaceutical customers to return product within a specified period prior to and subsequent to the expiration date (generally, three to six months before and 12 months after product expiration). The estimate of the provision for returns is based upon historical experience with actual returns. Additionally, the Company considers factors such as levels of inventory in the distribution channel, product dating and expiration period, whether products have been discontinued, entrance in the market of generic or other competition, changes in formularies or launch of over-the-counter products, among others. Outside of the U.S., returns are only allowed in certain countries on a limited basis.
Merck’s payment terms for U.S. pharmaceutical customers are typically 36 days from receipt of invoice and for U.S. animal health customers are typically 30 days from receipt of invoice; however, certain products have longer payment terms, including Keytruda (pembrolizumab), which has payment terms of 90 days. Payment terms for vaccine sales in the U.S. typically range from 30 days to 60 days. Outside of the U.S., payment terms are typically 30 days to 90 days, although certain markets have longer payment terms.
See Note 18 for disaggregated revenue disclosures.
Depreciation Depreciation — Depreciation is provided over the estimated useful lives of the assets, principally using the straight-line method. For tax purposes, accelerated tax methods are used. The estimated useful lives primarily range from 25 to 45 years for Buildings, and from 3 to 15 years for Machinery, equipment and office furnishings.
Advertising and Promotion Costs Advertising and Promotion Costs — Advertising and promotion costs are expensed as incurred.
Software Capitalization
Software Capitalization — The Company capitalizes certain costs incurred in connection with obtaining or developing internal-use software including external direct costs of material and services, and payroll costs for employees directly involved with the software development. These costs are included in Property, plant and equipment. In addition, the Company capitalizes certain costs incurred to implement a cloud computing arrangement
that is considered a service agreement, which are included in Other Assets. Capitalized software costs are being amortized over periods ranging from 2 to 10 years, with the longer lives generally associated with enterprise-wide projects implemented over multiple years. Costs incurred during the preliminary project stage and post-implementation stage, as well as maintenance and training costs, are expensed as incurred.
Goodwill
Goodwill — Goodwill represents the excess of the consideration transferred over the fair value of net assets acquired in a business combination. Goodwill is assigned to reporting units and evaluated for impairment at least annually, or more frequently if impairment indicators exist, by first assessing qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If the Company concludes it is more likely than not that the fair value of a reporting unit is less than its carrying amount, a quantitative fair value test is performed. If the carrying value of a reporting unit is greater than its fair value, a goodwill impairment charge will be recorded for the difference (up to the carrying value of goodwill).
Acquired Intangibles
Acquired Intangibles — Intangibles acquired in a business combination include product rights, trade names and patents, licenses and other, which are initially recorded at fair value, assigned an estimated useful life, and amortized primarily on a straight-line basis over their estimated useful lives ranging from 2 to 24 years. The Company periodically evaluates whether current facts or circumstances indicate that the carrying values of its acquired intangibles may not be recoverable. If such circumstances are determined to exist, an estimate of the undiscounted future cash flows of these assets, or appropriate asset groupings, is compared to the carrying value to determine whether an impairment exists. If the asset is determined to be impaired, the loss is measured based on the difference between the carrying value of the intangible asset and its fair value, which is determined based on the net present value of estimated future cash flows.
Acquired In-Process Research and Development
Acquired In-Process Research and Development — IPR&D that the Company acquires in conjunction with a business combination represents the fair value assigned to incomplete research projects which, at the time of acquisition, have not reached technological feasibility. The amounts are capitalized and are accounted for as indefinite-lived intangible assets, subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each IPR&D project, Merck will make a determination as to the then-useful life of the intangible asset, generally determined by the period in which the substantial majority of the cash flows are expected to be generated, and begin amortization. The Company evaluates IPR&D for impairment at least annually, or more frequently if impairment indicators exist, by performing a quantitative test that compares the fair value of the IPR&D intangible asset with its carrying value. If the fair value is less than the carrying amount, an impairment loss is recognized in operating results.
Contingent Consideration for Business Combinations Contingent Consideration for Business Combinations — Certain of the Company’s acquisitions involve the potential for future payment of consideration that is contingent upon the achievement of performance milestones, including product development milestones and royalty payments on future product sales. If the transaction is accounted for as a business combination, the fair value of contingent consideration liabilities is determined at the acquisition date using unobservable inputs. These inputs include the estimated amount and timing of projected cash flows, the probability of success (achievement of the contingent event) and the risk-adjusted discount rate used to present value the probability-weighted cash flows. Subsequent to the acquisition date, at each reporting period until the contingency is resolved, the contingent consideration liability is remeasured at current fair value with changes (either expense or income) recorded in earnings. Significant events that increase or decrease the probability of achieving development and regulatory milestones or that increase or decrease projected cash flows will result in corresponding increases or decreases in the fair values of the related contingent consideration obligations.
Research and Development Research and Development — Research and development is expensed as incurred. Nonrefundable advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. Research and development expenses include restructuring costs and IPR&D impairment charges. In addition, research and development expenses include expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration associated with IPR&D assets. Research and development expenses also include upfront and milestone payments related to asset acquisitions and licensing transactions involving clinical development programs that have not yet received regulatory approval.
Collaborative Arrangements
Collaborative Arrangements — Merck has entered into collaborative arrangements that provide the Company with varying rights to develop, produce and market products together with its collaborative partners. When Merck is the principal on sales transactions with third parties, the Company recognizes sales, cost of sales and selling, general and administrative expenses on a gross basis. Profit sharing amounts it pays to its collaborative partners are recorded within Cost of sales. When the collaborative partner is the principal on sales transactions with third parties, the Company records profit sharing amounts received from its collaborative partners as alliance revenue
(within Sales). Alliance revenue is recorded net of cost of sales and includes an adjustment to share commercialization costs between the partners in accordance with the collaboration agreement. The adjustment is determined by comparing the commercialization costs Merck has incurred directly and reported within Selling, general and administrative expenses with the costs the collaborative partner has incurred. Research and development costs Merck incurs related to collaborations are recorded within Research and development expenses. Cost reimbursements to the collaborative partner or payments received from the collaborative partner to share these costs pursuant to the terms of the collaboration agreements are recorded as increases or decreases to Research and development expenses.
In addition, the terms of the collaboration agreements may require the Company to make payments based upon the achievement of certain developmental, regulatory approval or commercial milestones. Upfront and milestone payments payable by Merck to collaborative partners prior to regulatory approval are expensed as incurred and included in Research and development expenses. Payments due to collaborative partners upon or subsequent to regulatory approval are capitalized and amortized to Cost of sales over the estimated useful life of the corresponding intangible asset, provided that future cash flows support the amounts capitalized. Sales-based milestones payable by Merck to collaborative partners are accrued and capitalized, subject to cumulative amortization catch-up, when determined by the Company to be probable of being achieved based on future sales forecasts. The amortization catch-up is calculated either from the time of the first regulatory approval for products that were unapproved at the time the collaboration was formed or, for new indications of approved products, from the time of the formation of the collaboration. The related intangible asset that is recognized is amortized to Cost of sales over its remaining useful life, subject to impairment testing.
Share-Based Compensation
Share-Based Compensation — The Company expenses all share-based payments to employees over the requisite service period based on the grant-date fair value of the awards.
Restructuring Costs
Restructuring Costs — The Company records liabilities for costs associated with exit or disposal activities in the period in which the liability is incurred. In accordance with existing benefit arrangements, future employee termination costs to be incurred in conjunction with involuntary separations are accrued when such separations are probable and estimable. When accruing these costs, the Company will recognize the amount within a range of costs that is the best estimate within the range. When no amount within the range is a better estimate than any other amount, the Company recognizes the minimum amount within the range. Costs for one-time termination benefits in which the employee is required to render service until termination in order to receive the benefits are recognized ratably over the future service period.
Contingencies and Legal Defense Costs
Contingencies and Legal Defense Costs — The Company records accruals for contingencies and legal defense costs expected to be incurred in connection with a loss contingency when it is probable that a liability has been incurred and the amount can be reasonably estimated.
Taxes on Income
Taxes on Income — Deferred taxes are recognized for the future tax effects of temporary differences between financial and income tax reporting based on enacted tax laws and rates. The Company evaluates tax positions to determine whether the benefits of tax positions are more likely than not of being sustained upon audit based on the technical merits of the tax position. For tax positions that are more likely than not of being sustained upon audit, the Company recognizes the amount of the benefit that is greater than 50% likely of being realized upon ultimate settlement in the financial statements. For tax positions that are not more likely than not of being sustained upon audit, the Company does not recognize any portion of the benefit in the financial statements. The Company recognizes interest and penalties associated with uncertain tax positions as a component of Taxes on Income. The Company accounts for the tax effects of the tax on global intangible low-taxed income (GILTI) of certain foreign subsidiaries in the income tax provision in the period the tax arises. The Company’s policy for releasing disproportionate income tax effects from AOCL is to utilize the item-by-item approach.
Reclassifications Reclassifications — Certain reclassifications have been made to prior year amounts to conform to the current year presentation.
Use of Estimates
Use of Estimates — The consolidated financial statements are prepared in conformity with accounting principles generally accepted in the U.S. (GAAP) and, accordingly, include certain amounts that are based on management’s best estimates and judgments. Estimates are used when accounting for amounts recorded in connection with acquisitions, including initial fair value determinations of assets and liabilities in a business combination (primarily IPR&D, other intangible assets and contingent consideration), as well as subsequent fair value measurements. Additionally, estimates are used in determining such items as provisions for sales discounts, rebates and returns, depreciable and amortizable lives, recoverability of inventories, including those produced in preparation for product launches, amounts recorded for contingencies, environmental liabilities, accruals for contingent sales-
based milestone payments and other reserves, pension and other postretirement benefit plan assumptions, share-based compensation assumptions, restructuring costs, impairments of long-lived assets (including intangible assets and goodwill) and investments, and taxes on income. Because of the uncertainty inherent in such estimates, actual results may differ from these estimates.
Recently Adopted Accounting Standards and Recently Issued Accounting Standards Not Yet Adopted
Recently Adopted Accounting Standards — In August 2023, the Financial Accounting Standards Board (FASB) issued amended guidance that requires a newly formed joint venture to recognize and initially measure its assets and liabilities at fair value upon formation. The amended guidance includes exceptions to fair value measurement that are consistent with the accounting for business combinations guidance. The Company adopted the guidance effective July 1, 2024 on a prospective basis. There was no impact to the Company’s consolidated financial statements upon adoption.
In November 2023, the FASB issued guidance intended to improve reportable segment disclosure requirements, primarily through expanded disclosures for significant segment expenses. The Company adopted the guidance effective for the 2024 annual period. The guidance resulted in incremental disclosures to the Company’s segment reporting disclosures. See Note 18 for further details.
Recently Issued Accounting Standards Not Yet Adopted — In December 2023, the FASB issued guidance intended to improve the transparency of income tax disclosures by requiring consistent categories and disaggregation of information in the effective income tax rate reconciliation and income taxes paid disclosures by jurisdiction. The guidance also includes other amendments to improve the effectiveness of income tax disclosures by removing certain previously required disclosures. The guidance is effective for 2025 annual reporting. The guidance will result in incremental disclosures within the footnotes to the Company’s financial statements.
In November 2024, the FASB issued guidance intended to improve financial reporting by requiring entities to disclose additional information about specific expense categories at interim and annual reporting periods. The guidance is effective for 2027 annual reporting and 2028 interim reporting. Early adoption is permitted. The guidance, which can be applied on a prospective or retrospective basis, will result in incremental disclosures within the footnotes to the Company’s financial statements.
v3.25.0.1
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements (Tables)
12 Months Ended
Dec. 31, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]  
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed
The estimated fair values of assets acquired and liabilities assumed from the Elanco aqua business are as follows:
July 9, 2024
Inventories
$65 
Property, plant and equipment
66
Product rights - Clynav (useful life 15 years) (1)
340
Other product rights (useful lives 15 years) (1)
291
Other assets and liabilities, net23 
Total identifiable net assets785 
Goodwill (2)
518
Consideration transferred$1,303 
(1)    The estimated fair values of Clynav and other product rights were determined using an income approach, specifically the multi-period excess earnings method. The future probability-weighted net cash flows were discounted to present value utilizing a discount rate of 8.5%. Actual cash flows are likely to be different than those assumed.
(2)    The goodwill recognized is largely attributable to anticipated synergies expected to arise after the acquisition and was allocated to the Animal Health segment. The goodwill is expected to be deductible for tax purposes.
v3.25.0.1
Collaborative Arrangements (Tables)
12 Months Ended
Dec. 31, 2024
Collaborative Arrangements [Abstract]  
Collaborative Arrangements
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Lynparza$1,311 $1,199 $1,116 
Alliance revenue - Koselugo170 97 54 
Total alliance revenue$1,481 $1,296 $1,170 
Cost of sales (1)
378 311 492 
Selling, general and administrative165 192 185 
Research and development77 79 106 
December 3120242023
Receivables from AstraZeneca included in Other current assets
$424 $341 
Payables to AstraZeneca included in Accrued and other current liabilities (2)
713 256 
Payables to AstraZeneca included in Other Noncurrent Liabilities (2)
 600 
(1)    Represents amortization of capitalized milestone payments. Amounts in 2024 and 2022 include $48 million and $250 million, respectively, of cumulative amortization catch-up expense as noted above.
(2)    Includes accrued milestone payments.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Lenvima$1,010 $960 $876 
Cost of sales (1)
241 381 212 
Selling, general and administrative159 189 158 
Research and development21 66 136 
December 3120242023
Receivables from Eisai included in Other current assets
$257 $226 
Payables to Eisai included in Accrued and other current liabilities (2)
 125 
(1)     Represents amortization of capitalized milestone payments. Amount in 2023 includes $154 million of cumulative amortization catch-up expense as noted above.
(2)     Represents an accrued milestone payment.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Alliance revenue - Adempas/Verquvo$415 $367 $341 
Net sales of Adempas recorded by Merck287 255 238 
Net sales of Verquvo recorded by Merck37 36 22 
Total sales$739 $658 $601 
Cost of sales (1)
244 224 210 
Selling, general and administrative111 131 153 
Research and development102 90 75 
December 3120242023
Receivables from Bayer included in Other current assets
$160 $156 
Payables to Bayer included in Accrued and other current liabilities
82 80 
(1)    Includes amortization of intangible assets, cost of products sold by Merck, as well as Bayer’s share of profits from sales in Merck’s marketing territories.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Net sales of Lagevrio recorded by Merck
$964 $1,428 $5,684 
Cost of sales (1)
554 852 3,038 
Selling, general and administrative
57 97 147 
Research and development
13 60 88 
December 3120242023
Payables to Ridgeback included in Accrued and other current liabilities (2)
$68 $113 
(1)    Includes cost of products sold by Merck, Ridgeback’s share of profits, royalty expense, amortization of capitalized milestone payments and inventory reserves.
(2)    Includes accrued royalties.
Summarized financial information related to this collaboration is as follows:
Years Ended December 3120242023
Selling, general and administrative
$26 $
Research and development (1)
351 5,549 
December 3120242023
Receivables from Daiichi Sankyo included in Other current assets
$8 $— 
Payables to Daiichi Sankyo included in Accrued and other current liabilities (2)
817 800 
Payables to Daiichi Sankyo included in Other Noncurrent Liabilities (2)
 750 
(1)    Expenses in 2023 include the $5.5 billion charge for the upfront and continuing option payments noted above.
(2)    Includes accrued continuation payment.
Summarized financial information related to this collaboration is as follows:
Years Ended December 31202420232022
Selling, general and administrative
$16 $$— 
Research and development (1)
358 218 288 
December 3120242023
Payables to Moderna included in Accrued and other current liabilities
$57 $63 
(1)    Expenses in 2022 include the $250 million option exercise payment noted above.
v3.25.0.1
Restructuring (Tables)
12 Months Ended
Dec. 31, 2024
Restructuring and Related Activities [Abstract]  
Charges Related to Restructuring Program Activities by Type of Cost
The following table summarizes the charges related to the restructuring programs by type of cost:
Accelerated
Depreciation
Separation
Costs
Other Exit Costs
Total
Year Ended December 31, 2024
2024 Restructuring Program
Cost of sales$254 $ $241 $495 
Selling, general and administrative  83 83 
Research and development  1 1 
Restructuring costs 122 187 309 
$254 $122 $512 $888 
Year Ended December 31, 2023
2024 Restructuring Program
Cost of sales$— $— $62 $62 
Restructuring costs— 115 13 128 
— 115 75 190 
2019 Restructuring Program
Cost of sales131 — 18 149 
Selling, general and administrative— 113 122 
Research and development— — 
Restructuring costs— 339 132 471 
 140 339 264 743 
$140 $454 $339 $933 
Year Ended December 31, 2022    
2019 Restructuring Program
Cost of sales$72 $— $133 $205 
Selling, general and administrative19 — 75 94 
Research and development29 — 30 
Restructuring costs— 212 125 337 
 $120 $212 $334 $666 
Charges and Spending Relating to Restructuring Activities by Program
The following table summarizes the charges and spending relating to restructuring program activities:
Accelerated
Depreciation
Separation
Costs
Other Exit Costs
Total
Restructuring reserves January 1, 2023
$— $479 $34 $513 
Expenses140 454 339 933 
(Payments) receipts, net— (252)(158)(410)
Non-cash activity(140)— (184)(324)
Restructuring reserves December 31, 2023
— 681 31 712 
Expenses254 122 512 888 
(Payments) receipts, net (239)(206)(445)
Non-cash activity(254) (337)(591)
Restructuring reserves December 31, 2024
$ $564 $ $564 
v3.25.0.1
Financial Instruments (Tables)
12 Months Ended
Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Effect of Net Investment Hedges
The effects of the Company’s net investment hedges on OCI and the Consolidated Statement of Income are shown below:
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (1)
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing
Years Ended December 31202420232022202420232022
Net Investment Hedging Relationships
Foreign exchange contracts$(30)$— $(48)$(4)$$(1)
Euro-denominated notes(192)105 (162) — — 
(1)    No amounts were reclassified from AOCL into income related to the sale of a subsidiary.
Summary of Interest Rate Derivatives
At December 31, 2024, the Company was a party to six pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of the fixed-rate notes as detailed in the table below.
Par Value of DebtNumber of Interest Rate Swaps HeldTotal Swap Notional Amount
4.50% notes due 2033
$1,500 $1,500 
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position
The table below presents the location of amounts recorded in the Consolidated Balance Sheet related to cumulative basis adjustments for fair value hedges as of December 31:
Carrying Amount of Hedged Liabilities
Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount
2024202320242023
Balance Sheet Caption
Long-Term Debt $1,509 $1,056 $17 $56 
Fair Value of Derivatives on a Gross Basis Segregated Between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments
Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments as of December 31:
  20242023
  Fair Value of
Derivative
U.S. Dollar
Notional
Fair Value of
Derivative
U.S. Dollar
Notional
 AssetLiabilityAssetLiability
Derivatives Designated as Hedging InstrumentsBalance Sheet Caption      
Interest rate swap contracts
Other Assets
$17 $ $1,500 $57 $— $1,000 
Foreign exchange contractsOther current assets323  8,662 106 — 6,138 
Foreign exchange contractsOther Assets66  2,125 26 — 1,929 
Foreign exchange contractsAccrued and other current liabilities 1 162 — 76 3,680 
Foreign exchange contractsOther Noncurrent Liabilities 1 16 — 
  $406 $2 $12,465 $189 $77 $12,754 
Derivatives Not Designated as Hedging InstrumentsBalance Sheet Caption      
Foreign exchange contractsOther current assets$323 $ $12,544 $153 $— $9,693 
Foreign exchange contractsAccrued and other current liabilities 343 13,551 — 162 8,104 
  $323 $343 $26,095 $153 $162 $17,797 
  $729 $345 $38,560 $342 $239 $30,551 
Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes as of December 31:
20242023
AssetLiabilityAssetLiability
Gross amounts recognized in the consolidated balance sheet$729 $345 $342 $239 
Gross amounts subject to offset in master netting arrangements not offset in the consolidated balance sheet(299)(299)(215)(215)
Cash collateral received
(165) (3)— 
Net amounts$265 $46 $124 $24 
Location and Pretax Gain or Loss Amounts for Derivatives
The table below provides information regarding the location and amount of pretax gains and losses of derivatives designated in fair value or cash flow hedging relationships:
Years Ended December 31202420232022202420232022202420232022
Financial Statement Caption in which Effects of Fair Value or Cash Flow Hedges are RecordedSales
Other (income) expense, net (1)
Other comprehensive income (loss)
$64,168 $60,115 $59,283 $(24)$466 $1,501 $216 $(393)$(339)
(Gain) loss on fair value hedging relationships:
Interest rate swap contracts
Hedged items — — (39)56 (13) — — 
Derivatives designated as hedging instruments — — 39 (57) — — 
Impact of cash flow hedging relationships:
Foreign exchange contracts
Amount of gain recognized in OCI on derivatives
 — —  — — 508 114 684 
Increase in Sales as a result of AOCL reclassifications
167 249 773  — — (167)(249)(773)
Interest rate contracts
Amount of gain recognized in Other (income) expense, net on derivatives
 — — (1)(1)(2) — — 
Amount of (loss) gain recognized in OCI on derivatives
 — —  — — (1)13 (2)
(1)    Interest expense is a component of Other (income) expense, net.
Income Statement Effects of Derivatives Not Designated as Hedging Instruments
The table below provides information regarding the income statement effects of derivatives not designated as hedging instruments:
Amount of Derivative Pretax Loss (Gain) Recognized in Income
Years Ended December 31202420232022
Derivatives Not Designated as Hedging InstrumentsIncome Statement Caption
Foreign exchange contracts (1)
Other (income) expense, net$251 $(6)$(49)
Foreign exchange contracts (2)
Sales(28)(37)
(1)    These derivative contracts primarily mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.
(2)     These derivative contracts serve as economic hedges of forecasted transactions.
Information on Investments in Debt and Equity Securities
Information on investments in debt and equity securities at December 31 is as follows:
 
 20242023
 Amortized
Cost
Gross UnrealizedFair
Value
Amortized
Cost
Gross UnrealizedFair
Value
GainsLossesGainsLosses
Commercial paper$348 $ $ $348 $252 $— $— $252 
U.S. government and agency securities188   188 72— — 72 
Corporate notes and bonds    13 — — 13 
Total debt securities$536 $ $ $536 $337 $— $— $337 
Publicly traded equity securities (1)
920 764 
Total debt and publicly traded equity securities$1,456 $1,101 
(1)    Unrealized net losses of $30 million were recorded in Other (income) expense, net in 2024 on equity securities still held at December 31, 2024. Unrealized net gains of $411 million were recorded in Other (income) expense, net in 2023 on equity securities still held at December 31, 2023.
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis
Financial assets and liabilities measured at fair value on a recurring basis at December 31 are summarized below:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3TotalLevel 1Level 2Level 3Total
  20242023
Assets
Investments
Commercial paper$ $348 $ $348 $— $252 $— $252 
U.S. government and agency securities 99  99 — — — — 
Publicly traded equity securities463   463 252 — — 252 
 463 447  910 252 252 — 504 
Other assets (1)
U.S. government and agency securities89   89 72 — — 72 
Corporate notes and bonds    13 — — 13 
Publicly traded equity securities (2)
457   457 512 — — 512 
546   546 597 — — 597 
Derivative assets (3)
Forward exchange contracts 499  499 — 202 — 202 
Purchased currency options 213  213 — 83 — 83 
Interest rate swaps 17  17 — 57 — 57 
  729  729 — 342 — 342 
Total assets$1,009 $1,176 $ $2,185 $849 $594 $— $1,443 
Liabilities
Other liabilities
Contingent consideration$ $ $193 $193 $— $— $354 $354 
Derivative liabilities (3)
Forward exchange contracts 338  338 — 239 — 239 
Written currency options 7  7 — — — — 
 345  345 — 239 — 239 
Total liabilities$ $345 $193 $538 $— $239 $354 $593 
(1)    Investments included in other assets are restricted as to use, including for the payment of benefits under employee benefit plans.
(2)    Balance at December 31, 2024 includes securities with a fair value of $81 million, which are subject to a contractual sale restriction that expires in March 2025. Balance at December 31, 2023 includes securities with a fair value of $177 million, which were subject to a contractual sale restriction that expired in July 2024.
(3)    The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.
Summarized Information about the Changes in Liabilities for Contingent Consideration
Summarized information about the changes in the fair value of liabilities for contingent consideration associated with business combinations is as follows:
20242023
Fair value January 1$354 $456 
Changes in estimated fair value (1)
(10)15 
Payments(151)(117)
Fair value December 31 (2)
$193 $354 
(1)    Recorded in Cost of sales, Research and development expenses, and Other (income) expense, net. Includes cumulative translation adjustments.
(2)    Balance at December 31, 2024 includes $148 million of current liabilities, of which $123 million relates to the termination of the Sanofi Pasteur MSD joint venture in 2016. As part of the termination, Merck recorded a liability for contingent future royalty payments of 11.5% on net sales of all Merck products that were previously sold by the joint venture through December 31, 2024. The fair value of this liability is determined utilizing the estimated amount and timing of projected cash flows using a risk-adjusted discount rate to present value the cash flows.
v3.25.0.1
Inventories (Tables)
12 Months Ended
Dec. 31, 2024
Inventory Disclosure [Abstract]  
Inventories
Inventories at December 31 consisted of:
20242023
Finished goods$2,022 $1,954 
Raw materials and work in process8,831 8,037 
Supplies289 277 

11,142 10,268 
Decrease to LIFO cost(840)(562)
 $10,302 $9,706 
Recognized as:
Inventories$6,109 $6,358 
Other Assets4,193 3,348 
Inventories
Inventories at December 31 consisted of:
20242023
Finished goods$2,022 $1,954 
Raw materials and work in process8,831 8,037 
Supplies289 277 

11,142 10,268 
Decrease to LIFO cost(840)(562)
 $10,302 $9,706 
Recognized as:
Inventories$6,109 $6,358 
Other Assets4,193 3,348 
v3.25.0.1
Goodwill and Other Intangibles (Tables)
12 Months Ended
Dec. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill Activity by Segment
The following table summarizes goodwill activity by segment:
PharmaceuticalAnimal HealthTotal
Balance January 1, 2023
$17,936 $3,268 $21,204 
Other (1)
(14)(7)
Balance December 31, 2023 (2)
17,922 3,275 21,197 
Acquisitions
 518 518 
Other (1)
(19)(28)(47)
Balance December 31, 2024 (2)
$17,903 $3,765 $21,668 
(1)    Includes cumulative translation adjustments on goodwill balances.
(2)    Accumulated goodwill impairment losses were $531 million at both December 31, 2024 and 2023.
Other Intangibles
Other acquired intangibles at December 31 consisted of:
 20242023
Gross
Carrying
Amount
Accumulated
Amortization
NetGross
Carrying
Amount
Accumulated
Amortization
Net
Product rights
$29,988 $19,066 $10,922 $23,643 $17,765 $5,878 
IPR&D430  430 6,816 — 6,816 
Trade names2,881 954 1,927 2,881 776 2,105 
Licenses and other8,863 5,772 3,091 8,263 5,051 3,212 
 $42,162 $25,792 $16,370 $41,603 $23,592 $18,011 
v3.25.0.1
Loans Payable, Long-Term Debt and Leases (Tables)
12 Months Ended
Dec. 31, 2024
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
Long-term debt at December 31 consisted of:
20242023
2.15% notes due 2031
$1,989 $1,988 
2.75% notes due 2051
1,980 1,980 
3.70% notes due 2045
1,980 1,979 
3.40% notes due 2029
1,742 1,740 
4.50% notes due 2033
1,509 1,547 
1.70% notes due 2027
1,497 1,495 
2.90% notes due 2061
1,484 1,484 
5.00% notes due 2053
1,482 1,481 
4.00% notes due 2049
1,474 1,473 
4.15% notes due 2043
1,240 1,240 
1.45% notes due 2030
1,240 1,238 
2.45% notes due 2050
1,216 1,214 
1.875% euro-denominated notes due 2026
1,041 1,103 
0.75% notes due 2026
998 996 
1.90% notes due 2028
996 995 
5.15% notes due 2063
987 987 
3.90% notes due 2039
987 986 
2.35% notes due 2040
986 985 
3.25% euro-denominated notes due 2032
880 — 
3.50% euro-denominated notes due 2037
877 — 
3.70% euro-denominated notes due 2044
876 — 
3.75% euro-denominated notes due 2054
873 — 
4.30% notes due 2030
746 745 
4.90% notes due 2044
740 740 
6.50% notes due 2033
702 707 
1.375% euro-denominated notes due 2036
517 548 
2.50% euro-denominated notes due 2034
517 548 
4.05% notes due 2028
498 497 
3.60% notes due 2042
492 492 
6.55% notes due 2037
404 406 
5.75% notes due 2036
339 339 
5.95% debentures due 2028
307 307 
5.85% notes due 2039
271 271 
6.40% debentures due 2028
251 250 
6.30% debentures due 2026
135 135 
2.75% notes due 2025
 2,498 
Other209 289 
$34,462 $33,683 
Supplemental Balance Sheet Information
Supplemental balance sheet information related to operating leases is as follows:
December 3120242023
Assets
Other Assets (1)
$1,370 $1,437 
Liabilities
Accrued and other current liabilities282 285 
Other Noncurrent Liabilities877 928 
$1,159 $1,213 
Weighted-average remaining lease term (years)6.07.0
Weighted-average discount rate3.2 %3.3 %
(1)    Includes prepaid leases that have no related lease liability.
Schedule of Maturities of Operating Lease Liabilities
Maturities of operating leases liabilities are as follows:
2025$329 
2026292 
2027235 
2028146 
2029116 
Thereafter403 
Total lease payments1,521 
Less: Imputed interest362 
$1,159 
v3.25.0.1
Equity (Tables)
12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Summary of Common Stock and Treasury Stock Transactions
A summary of common stock and treasury stock transactions (shares in millions) is as follows:
 202420232022
  Common
Stock
Treasury
Stock
Common
Stock
Treasury
Stock
Common
Stock
Treasury
Stock
Balance January 13,577 1,045 3,577 1,039 3,577 1,049 
Purchases of treasury stock 11 — 13 — — 
Issuances (1)
 (7)— (7)— (10)
Balance December 313,577 1,049 3,577 1,045 3,577 1,039 
(1)    Issuances primarily reflect activity under share-based compensation plans.
v3.25.0.1
Share-Based Compensation Plans (Tables)
12 Months Ended
Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]  
Assumptions Used to Determine Weighted-Average Fair Value of Options Granted The weighted average fair value of options granted in 2024, 2023 and 2022 was $25.60, $21.69 and $15.45 per option, respectively, and were determined using the following assumptions:
Years Ended December 31202420232022
Expected dividend yield3.0 %3.1 %3.1 %
Risk-free interest rate4.7 %3.4 %3.0 %
Expected volatility20.5 %22.4 %22.5 %
Expected life (years)5.85.85.9
Summarized Information Relative to Stock Option Plan Activity
Summarized information relative to stock option plan activity (options in thousands) is as follows:
Number
of Options
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Term (Years)
Aggregate
Intrinsic
Value
Outstanding January 1, 2024
13,527 $77.54 
Granted1,753 129.22 
Exercised(2,581)68.90 
Forfeited(199)111.48   
Outstanding December 31, 2024
12,500 $86.04 5.9$249 
Vested and expected to vest December 31, 202412,201 $85.10 5.9$249 
Exercisable December 31, 20249,084 $74.00 4.9$241 
Additional Information Pertaining to Stock Option Plans
Additional information pertaining to stock option plans is provided in the table below:
Years Ended December 31202420232022
Total intrinsic value of stock options exercised$144 $95 $225 
Fair value of stock options vested32 30 30 
Cash received from the exercise of stock options177 125 384 
Summary of Nonvested RSU and PSU Activity
A summary of nonvested RSU and PSU activity (shares in thousands) is as follows:
 RSUsPSUs
  Number
of Shares
Weighted
Average
Grant Date
Fair Value
Number
of Shares
Weighted
Average
Grant Date
Fair Value
Nonvested January 1, 2024
12,542 $100.10 1,966 $90.80 
Granted6,356 128.79 968 121.91 
Vested(6,091)92.97 (1,109)73.50 
Forfeited(575)113.18 (59)121.12 
Nonvested December 31, 202412,232 $117.94 1,766 $117.57 
Expected to vest December 31, 202410,976 $117.25 1,669 $116.26 
v3.25.0.1
Pension and Other Postretirement Benefit Plans (Tables)
12 Months Ended
Dec. 31, 2024
Retirement Benefits [Abstract]  
Components of Net Periodic Benefit Cost
The net periodic benefit cost (credit) for pension and other postretirement benefit plans consisted of the following components:
Pension Benefits
U.S.InternationalOther Postretirement Benefits
Years Ended December 31202420232022202420232022202420232022
Service cost$373 $326 $372 $243 $196 $283 $30 $32 $48 
Interest cost537 526 457 294 299 145 56 63 46 
Expected return on plan assets(826)(735)(753)(554)(517)(383)(80)(64)(86)
Amortization of unrecognized prior service (credit) cost
 (1)(32)(13)(14)(43)(49)(57)
Net loss (gain) amortization43 — 128 5 (3)96 (51)(42)(43)
Termination benefits5 1 — 4 — — 
Curtailments 12  (1)—  (1)(1)
Settlements 28 239 (1)(5) — — 
Net periodic benefit cost (credit)$132 $155 $425 $(25)$(29)$129 $(84)$(61)$(93)
Obligation and Funded Status
Summarized information about the changes in plan assets and benefit obligations, the funded status and the amounts recorded at December 31 is as follows:

Pension BenefitsOther
Postretirement
Benefits
U.S.International
202420232024202320242023
Fair value of plan assets January 1$9,804 $9,094 $9,562 $8,473 $1,045 $947 
Actual return on plan assets266 1,077 637 832 35 115 
Company contributions262 307 198 249 46 74 
Effects of exchange rate changes — (522)283  — 
Benefits paid(615)(497)(250)(256)(89)(95)
Settlements (177)(14)(53) (2)
Other — 36 34 3 
Fair value of plan assets December 31$9,717 $9,804 $9,647 $9,562 $1,040 $1,045 
Benefit obligation January 1$10,446 $9,854 $9,042 $7,755 $1,104 $1,157 
Service cost373 326 243 196 30 32 
Interest cost537 526 294 299 56 63 
Actuarial (gains) losses (1)
(595)403 (549)766 32 (58)
Benefits paid(615)(497)(250)(256)(89)(95)
Effects of exchange rate changes — (473)288 (4)
Plan amendments — (56)14  — 
Curtailments  (1) — 
Termination benefits5 1 — 4 — 
Settlements (177)(14)(53) (2)
Other — 36 34 3 
Benefit obligation December 31$10,151 $10,446 $8,274 $9,042 $1,136 $1,104 
Funded status December 31$(434)$(642)$1,373 $520 $(96)$(59)
Recognized as:
Other Assets$26 $— $1,785 $1,019 $51 $107 
Accrued and other current liabilities(55)(49)(18)(19)(7)(8)
Other Noncurrent Liabilities(405)(593)(394)(480)(140)(158)
(1)    Actuarial (gains) losses primarily reflect changes in discount rates.
Funded Status of Selected Pension Plans
Information related to the funded status of selected pension plans at December 31 is as follows:
U.S.International
2024202320242023
Pension plans with a projected benefit obligation in excess of plan assets
Projected benefit obligation
$9,517 $10,446 $1,847 $2,961 
Fair value of plan assets9,057 9,804 1,435 2,462 
Pension plans with an accumulated benefit obligation in excess of plan assets
Accumulated benefit obligation$442 $9,700 $1,768 $1,791 
Fair value of plan assets 9,186 1,385 1,336 
Funded Status of Selected Pension Plans
Information related to the funded status of selected pension plans at December 31 is as follows:
U.S.International
2024202320242023
Pension plans with a projected benefit obligation in excess of plan assets
Projected benefit obligation
$9,517 $10,446 $1,847 $2,961 
Fair value of plan assets9,057 9,804 1,435 2,462 
Pension plans with an accumulated benefit obligation in excess of plan assets
Accumulated benefit obligation$442 $9,700 $1,768 $1,791 
Fair value of plan assets 9,186 1,385 1,336 
Schedule of Allocation of Plan Assets
The fair values of the Company’s pension plan assets at December 31 by asset category are as follows:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3
NAV (1)
TotalLevel 1Level 2Level 3
NAV (1)
Total
20242023
U.S. Pension Plans
Cash and cash equivalents$43 $ $ $121 $164 $34 $— $— $124 $158 
Investment funds
Developed markets equities170   2,385 2,555 224 — — 2,573 2,797 
Emerging markets equities   1,265 1,265 — — — 740 740 
Real estate   174 174 — — — 113 113 
Equity securities
Developed markets2,171    2,171 2,071 — — — 2,071 
Fixed income securities
Government and agency obligations 2,101   2,101 — 2,307 — — 2,307 
Corporate obligations 1,293   1,293 — 1,485 — — 1,485 
Mortgage and asset-backed securities 21   21 — 21 — — 21 
Other investments (liabilities)
Derivatives(29)   (29)109 — — — 109 
Other  2  2 — — — 
Plan assets at fair value$2,355 $3,415 $2 $3,945 $9,717 $2,438 $3,813 $$3,550 $9,804 
International Pension Plans
Cash and cash equivalents$112 $ $ $11 $123 $98 $— $— $20 $118 
Investment funds
Developed markets equities599 3,537  96 4,232 507 3,257 — 106 3,870 
Government and agency obligations262 2,974  149 3,385 234 3,123 — 166 3,523 
Corporate obligations23 8  149 180 23 — 166 197 
Emerging markets equities54   91 145 44 — — 66 110 
Other fixed income obligations8 7  4 19 — 20 
Real estate   12 12 — — — 10 10 
Equity securities
Developed markets287    287 278 — — — 278 
Fixed income securities
Government and agency obligations 368   368 — 423 — — 423 
Corporate obligations 141   141 — 160 — — 160 
Mortgage and asset-backed securities 54   54 — 61 — — 61 
Other investments
Insurance contracts (2)
 1 698 2 701 — 785 788 
Other     — — — 
Plan assets at fair value$1,345 $7,090 $698 $514 $9,647 $1,197 $7,041 $785 $539 $9,562 
(1)    Certain investments that were measured at net asset value (NAV) per share or its equivalent have not been classified in the fair value hierarchy. The NAV amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the fair value of plan assets at December 31, 2024 and 2023.
(2)    The plans’ Level 3 investments in insurance contracts are generally valued using a crediting rate that approximates market returns and invest in underlying securities whose market values are unobservable and determined using pricing models, discounted cash flow methodologies, or similar techniques.
The fair values of the Company’s other postretirement benefit plan assets at December 31 by asset category are as follows:
 Fair Value Measurements UsingFair Value Measurements Using
Level 1Level 2Level 3
NAV (1)
TotalLevel 1Level 2Level 3
NAV (1)
Total
20242023
Cash and cash equivalents$ $ $ $5 $5 $— $— $— $13 $13 
Investment funds
Developed markets equities3   46 49 24 — — 277 301 
Emerging markets equities   24 24 — — — 80 80 
Real estate   3 3 — — — 12 12 
Equity securities
Developed markets41   41 223 — — — 223 
Fixed income securities
Corporate obligations 598  598 — 157 — — 157 
Government and agency obligations 266  266 — 245 — — 245 
Mortgage and asset-backed securities 54   54 — — — 
Other Investments (liabilities)
Derivatives     12 — — — 12 
Plan assets at fair value$44 $918 $ $78 $1,040 $259 $404 $— $382 $1,045 
(1)    Certain investments that were measured at net asset value (NAV) per share or its equivalent have not been classified in the fair value hierarchy. The NAV amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the fair value of plan assets at December 31, 2024 and 2023.
Summary of Changes in Fair Value of Company's Level 3 Pension Plan Assets
The table below provides a summary of the changes in fair value, including transfers in and/or out, of all financial assets measured at fair value using significant unobservable inputs (Level 3) for the Company’s pension plan assets:
 20242023
Insurance
Contracts
OtherTotalInsurance
Contracts
OtherTotal
U.S. Pension Plans
Balance January 1$ $3 $3 $— $$
Actual return on plan assets:
Relating to assets still held at December 31 (2)(2)— (2)(2)
Relating to assets sold during the year 2 2 — 
Purchases and sales, net (1)(1)— (1)(1)
Balance December 31$ $2 $2 $— $$
International Pension Plans
Balance January 1$785 $ $785 $761 $— $761 
Actual return on plan assets:
Relating to assets still held at December 31(26) (26)77 — 77 
Purchases and sales, net(61) (61)(53)— (53)
Balance December 31$698 $ $698 $785 $— $785 
Summary of Expected Benefit Payments
Expected benefit payments are as follows:
U.S. Pension BenefitsInternational Pension
Benefits
Other
Postretirement
Benefits
2025$771 $291 $86 
2026775 275 87 
2027789 286 89 
2028799 300 91 
2029822 314 96 
2030 — 2034
4,386 1,792 515 
Components of Other Comprehensive Income (Loss) The following amounts were reflected as components of OCI:
 Pension PlansOther Postretirement
Benefit Plans
U.S.International
Years Ended December 31202420232022202420232022202420232022
Net gain (loss) arising during the period
$35 $(69)$(42)$634 $(438)$116 $(78)$110 $— 
Prior service credit (cost) arising during the period
 — — 56 (16)(4) — — 
 $35 $(69)$(42)$690 $(454)$112 $(78)$110 $— 
Net loss (gain) amortization included in benefit cost$43 $— $128 $5 $(3)$96 $(51)$(42)$(43)
Prior service (credit) cost amortization included in benefit cost
 (1)(32)(13)(14)(43)(49)(57)
Settlements and curtailments 36 251 (1)(6) (1)(1)
 $43 $35 $347 $(9)$(7)$83 $(94)$(92)$(101)
Summary of Weighted Average Assumptions Used in Determining Pension Plan and U.S. Pension and Other Postretirement Benefit Plan Information
The Company reassesses its benefit plan assumptions on a regular basis. The weighted average assumptions used in determining U.S. pension and other postretirement benefit plan and international pension plan information are as follows:
 U.S. Pension and Other
Postretirement Benefit Plans
International Pension Plans
December 31202420232022202420232022
Net periodic benefit cost      
Discount rate5.30 %5.50 %3.00 %3.40 %3.90 %1.50 %
Expected rate of return on plan assets7.75 %7.00 %6.70 %5.20 %5.00 %3.70 %
Salary growth rate4.60 %4.60 %4.60 %3.20 %3.20 %2.90 %
Interest crediting rate5.30 %5.30 %5.00 %3.40 %3.30 %3.00 %
Benefit obligation      
Discount rate5.70 %5.30 %5.50 %3.70 %3.40 %3.90 %
Salary growth rate4.80 %4.60 %4.60 %3.10 %3.20 %3.20 %
Interest crediting rate5.40 %5.30 %5.30 %3.50 %3.40 %3.30 %
Summary of Health Care Cost Trend Rate Assumptions for Other Postretirement Benefit Plans
The health care cost trend rate assumptions for other postretirement benefit plans are as follows:
December 3120242023
Health care cost trend rate assumed for next year7.90 %7.80 %
Rate to which the cost trend rate is assumed to decline4.50 %4.50 %
Year that the trend rate reaches the ultimate trend rate20402038
v3.25.0.1
Other (Income) Expense, Net (Tables)
12 Months Ended
Dec. 31, 2024
Other Income and Expenses [Abstract]  
Other (Income) Expense, Net
Other (income) expense, net, consisted of:
Years Ended December 31202420232022
Interest income$(415)$(365)$(157)
Interest expense1,271 1,146 962 
Exchange losses227 370 237 
(Income) loss from investments in equity securities, net (1)
(14)(340)1,419 
Net periodic defined benefit plan (credit) cost other than service cost(633)(498)(279)
Other, net(460)153 (681)
 $(24)$466 $1,501 
(1)    Includes net realized and unrealized gains and losses from investments in equity securities either owned directly or through ownership interests in investment funds. Unrealized gains and losses from investments that are directly owned are determined at the end of the reporting period, while gains and losses from ownership interests in investment funds are accounted for on a one quarter lag.
v3.25.0.1
Taxes on Income (Tables)
12 Months Ended
Dec. 31, 2024
Income Tax Disclosure [Abstract]  
Reconciliation Between Effective Tax Rate and U.S. Statutory Rate
A reconciliation between the effective tax rate and the U.S. statutory rate is as follows:
 202420232022
AmountTax RateAmountTax RateAmountTax Rate
U.S. statutory rate applied to income before taxes
$4,186 21.0 %$397 21.0 %$3,453 21.0 %
Differential arising from:
Foreign earnings(1,301)(6.5)(941)(49.8)(1,821)(11.1)
Tax settlements and statute lapses
(557)(2.8)— — (10)(0.1)
R&D tax credit(202)(1.0)(214)(11.3)(117)(0.7)
Inventory donations
(71)(0.4)(65)(3.5)(52)(0.3)
State taxes(39)(0.2)(117)(6.2)(110)(0.7)
Charges for certain research and development asset acquisitions
554 2.8 253 13.4 — — 
Valuation allowances54 0.3 70 3.7 108 0.7 
Restructuring52 0.3 41 2.2 11 0.1 
GILTI and the foreign-derived intangible income deduction29 0.1 (80)(4.3)462 2.8 
Acquisition-related costs, including amortization
18 0.1 42 2.2 (3)— 
Acquisition of Prometheus
  2,139 113.3 — — 
Other80 0.4 (13)(0.7)(3)— 
 $2,803 14.1 %$1,512 80.0 %$1,918 11.7 %
Where applicable, the impact of changes in uncertain tax positions is reflected in the reconciling items above.
Income Before Taxes
Income before taxes consisted of:
Years Ended December 31202420232022
Domestic$(1,849)$(15,622)$1,011 
Foreign21,785 17,511 15,433 
 $19,936 $1,889 $16,444 
Taxes on Income
Taxes on income consisted of:
Years Ended December 31202420232022
Current provision
Federal$944 $928 $2,265 
Foreign3,123 2,435 1,164 
State(15)48 57 
 4,052 3,411 3,486 
Deferred provision
Federal(1,475)(1,559)(1,510)
Foreign212 (233)71 
State14 (107)(129)
 (1,249)(1,899)(1,568)
 $2,803 $1,512 $1,918 
Deferred Income Taxes
Deferred income taxes at December 31 consisted of:
 20242023
AssetsLiabilitiesAssetsLiabilities
Product intangibles and licenses$71 $978 $— $1,308 
R&D capitalization3,062  2,099 — 
Inventory related84 413 86 370 
Accelerated depreciation 645 — 626 
Undistributed foreign earnings
275 371 76 118 
Equity investments 90 — 73 
Pensions and other postretirement benefits224 400 323 249 
Compensation related400  357 — 
Unrecognized tax benefits152  147 — 
Net operating losses and other tax credit carryforwards910  868 — 
Other802 159 755 214 
Subtotal5,980 3,056 4,711 2,958 
Valuation allowance(710) (656) 
Total deferred taxes$5,270 $3,056 $4,055 $2,958 
Net deferred income taxes$2,214 $1,097 
Recognized as:
Other Assets$3,601 $1,968 
Deferred Income Taxes $1,387  $871 
Income Taxes Paid
Income taxes paid in 2024, 2023 and 2022 consisted of:
Years Ended December 31202420232022
Domestic (1)
$974 $2,258 $1,891 
Foreign2,954 2,080 1,348 
 $3,928 $4,338 $3,239 
(1)    Includes TCJA transition tax payments.
Unrecognized Tax Benefits
A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
202420232022
Balance January 1$2,384 $1,835 $1,529 
Additions related to current year positions421 553 344 
Additions related to prior year positions35 91 48 
Reductions for tax positions of prior years
(33)(20)(40)
Settlements
(18)(23)(6)
Lapse of statute of limitations (1)
(528)(52)(40)
Balance December 31$2,261 $2,384 $1,835 
(1)    Amount in 2024 reflects a reduction of $451 million resulting from the expiration of the statute of limitations related to the 2019 and 2020 federal tax return years.
v3.25.0.1
Earnings per Share (Tables)
12 Months Ended
Dec. 31, 2024
Earnings Per Share [Abstract]  
Calculations of Earnings Per Share
The calculations of earnings per share (shares in millions) are as follows:
Years Ended December 31202420232022
Net Income Attributable to Merck & Co., Inc.$17,117 $365 $14,519 
Average common shares outstanding2,532 2,537 2,532 
Common shares issuable (1)
9 10 10 
Average common shares outstanding assuming dilution2,541 2,547 2,542 
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders
$6.76 $0.14 $5.73 
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders
$6.74 $0.14 $5.71 
(1)     Issuable primarily under share-based compensation plans.
v3.25.0.1
Other Comprehensive Income (Loss) (Tables)
12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Changes in AOCI by Component
Changes in each component of other comprehensive income (loss) are as follows:
DerivativesEmployee
Benefit
Plans
 Foreign Currency
Translation
Adjustment
Accumulated Other
Comprehensive Loss
Balance at January 1, 2022, net of taxes
$144 $(2,743)$(1,830)$(4,429)
Other comprehensive income (loss) before reclassification adjustments, pretax684 70 (584)170 
Tax(143)12 (19)(150)
Other comprehensive income (loss) before reclassification adjustments, net of taxes541 82 (603)20 
Reclassification adjustments, pretax(775)
(1)
329 
(2)
— (446)
Tax163 (76)— 87 
Reclassification adjustments, net of taxes(612)253 — (359)
Other comprehensive income (loss), net of taxes(71)335 (603)(339)
Balance at December 31, 2022, net of taxes73 (2,408)(2,433)(4,768)
Other comprehensive income (loss) before reclassification adjustments, pretax114 (413)17 (282)
Tax(24)86 63 125 
Other comprehensive income (loss) before reclassification adjustments, net of taxes90 (327)80 (157)
Reclassification adjustments, pretax(237)
(1)
(64)
(2)
(292)
Tax50 — 56 
Reclassification adjustments, net of taxes(187)(58)(236)
Other comprehensive income (loss), net of taxes(97)(385)89 (393)
Balance at December 31, 2023, net of taxes(24)(2,793)
(3)
(2,344)(5,161)
Other comprehensive income (loss) before reclassification adjustments, pretax508 647 (559)596 
Tax(109)(138)23 (224)
Other comprehensive income (loss) before reclassification adjustments, net of taxes399 509 (536)372 
Reclassification adjustments, pretax(168)
(1)
(60)
(2)
20 (208)
Tax35 17  52 
Reclassification adjustments, net of taxes(133)(43)20 (156)
Other comprehensive income (loss), net of taxes266 466 (516)216 
Balance at December 31, 2024, net of taxes$242 $(2,327)
(3)
$(2,860)$(4,945)
(1)    Primarily relates to foreign currency cash flow hedges that were reclassified from AOCL to Sales (see Note 6).
(2)    Includes net amortization of prior service cost, actuarial gains and losses, settlements and curtailments included in net periodic benefit cost (see Note 13).
(3)    Includes pension plan net loss of $3.0 billion and $3.5 billion at December 31, 2024 and 2023, respectively, and other postretirement benefit plan net gain of $400 million and $500 million at December 31, 2024 and 2023, respectively, as well as pension plan prior service credit of $174 million and $141 million at December 31, 2024 and 2023, respectively, and other postretirement benefit plan prior service credit of $61 million and $95 million at December 31, 2024 and 2023, respectively.
v3.25.0.1
Segment Reporting (Tables)
12 Months Ended
Dec. 31, 2024
Segment Reporting [Abstract]  
Sales of Company's Products
Sales of the Company’s products were as follows:
Years Ended December 31202420232022
U.S.Int’lTotalU.S.Int’lTotalU.S.Int’lTotal
Pharmaceutical:
Oncology
Keytruda$17,872 $11,610 $29,482 $15,114 $9,897 $25,011 $12,686 $8,251 $20,937 
Alliance revenue - Lynparza (1)
626 685 1,311 607 592 1,199 584 532 1,116 
Alliance revenue - Lenvima (1)
705 305 1,010 657 303 960 579 297 876 
Welireg466 43 509 209 10 218 123 — 123 
Alliance revenue - Reblozyl (2)
303 68 371 168 43 212 123 43 166 
Vaccines
Gardasil/Gardasil 9
2,425 6,158 8,583 2,083 6,803 8,886 2,065 4,832 6,897 
ProQuad/M-M-R II/Varivax1,919 566 2,485 1,837 531 2,368 1,724 518 2,241 
Vaxneuvance461 347 808 561 103 665 163 170 
RotaTeq472 239 711 493 276 769 508 275 783 
Pneumovax 23
56 207 263 127 285 412 346 256 602 
Hospital Acute Care
Bridion1,401 363 1,764 1,156 686 1,842 922 762 1,685 
Prevymis371 414 785 264 341 605 188 240 428 
Dificid303 37 340 274 28 302 241 22 263 
Zerbaxa146 106 252 119 100 218 89 79 169 
Noxafil7 170 177 32 181 213 51 187 238 
Cardiovascular
Winrevair
408 11 419 — — — — — — 
Alliance revenue - Adempas/Verquvo (3)
388 27 415 350 16 367 329 12 341 
Adempas 287 287 — 255 255 — 238 238 
Virology
Lagevrio176 787 964 10 1,418 1,428 1,523 4,161 5,684 
Isentress/Isentress HD185 209 394 215 268 483 274 359 633 
Delstrigo
56 193 249 49 152 201 39 111 151 
Pifeltro
113 50 163 101 41 142 87 30 118 
Neuroscience
Belsomra72 150 222 81 150 231 79 179 258 
Immunology
Simponi 543 543 — 710 710 — 706 706 
Remicade 114 114 — 187 187 — 207 207 
Diabetes
Januvia469 865 1,334 1,151 1,039 2,189 1,248 1,565 2,813 
Janumet161 774 935 223 954 1,177 355 1,344 1,700 
Other pharmaceutical (4)
729 1,782 2,510 658 1,675 2,333 663 1,803 2,462 
Total Pharmaceutical segment sales30,290 27,110 57,400 26,539 27,044 53,583 24,989 27,016 52,005 
Animal Health:
Livestock732 2,729 3,462 700 2,637 3,337 710 2,590 3,300 
Companion Animal1,129 1,287 2,415 1,104 1,184 2,288 1,112 1,138 2,250 
Total Animal Health segment sales1,861 4,016 5,877 1,804 3,821 5,625 1,822 3,728 5,550 
Total segment sales32,151 31,126 63,277 28,343 30,865 59,208 26,811 30,744 57,555 
Other (5)
126 765 891 137 770 907 395 1,333 1,728 
 $32,277 $31,891 $64,168 $28,480 $31,635 $60,115 $27,206 $32,077 $59,283 
U.S. plus international may not equal total due to rounding.
(1)    Alliance revenue for Lynparza and Lenvima represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs (see Note 4).
(2)    Alliance revenue for Reblozyl represents royalties and, for 2022, also includes a payment received related to the achievement of a regulatory approval milestone (see Note 4).
(3)    Alliance revenue for Adempas/Verquvo represents Merck’s share of profits from sales in Bayer’s marketing territories, which are product sales net of cost of sales and commercialization costs (see Note 4).
(4)    Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately.
(5)    Other is primarily comprised of miscellaneous corporate revenue, including revenue hedging activities which increased sales by $195 million, $244 million and $810 million in 2024, 2023 and 2022, respectively, as well as revenue from third-party manufacturing arrangements (including sales to Organon). Other for 2024, 2023 and 2022 also includes $106 million, $118 million and $165 million, respectively, related to upfront and milestone payments received by Merck for out-licensing arrangements.
Consolidated Revenues by Geographic Area
Consolidated sales by geographic area where derived are as follows:
Years Ended December 31202420232022
United States$32,277 $28,480 $27,206 
Europe, Middle East and Africa14,041 13,254 14,493 
China5,494 6,802 5,191 
Latin America3,459 3,086 2,582 
Japan3,280 3,164 3,629 
Asia Pacific (other than China and Japan)3,058 3,225 3,614 
Other2,559 2,104 2,568 
 $64,168 $60,115 $59,283 
Reconciliation of Segment Profits to Income Before Taxes
A reconciliation of segment profits to Income Before Taxes is as follows:
Years Ended December 31202420232022
Pharma-ceutical
Animal Health
Total
Pharma-ceutical
Animal Health
Total
Pharma-ceutical
Animal Health
Total
Segment sales
$57,400 $5,877 $63,277 $53,583 $5,625 $59,208 $52,005 $5,550 $57,555 
Less segment costs: (1)
Cost of sales
6,828 2,469 8,849 2,498 9,678 2,259 
Selling, general and administrative
6,128 1,084 5,903 1,038 5,474 999 
Research and development (2)
 385 — 353 — 329 
Other segment items (3)
(89)1 (49)(1)— 
Total segment profits44,533 1,938 46,471 38,880 1,737 40,617 36,852 1,963 38,815 
Other profits492 474 1,160 
Unallocated:
Interest income415 365 157 
Interest expense(1,271)(1,146)(962)
Amortization(2,395)(2,044)(2,085)
Depreciation(1,843)(1,625)(1,642)
Research and development(17,350)(30,008)(13,011)
Restructuring costs(309)(599)(337)
Charge for Zetia antitrust litigation settlements (573)— 
Other unallocated, net(4,274)(3,572)(5,651)
$19,936 $1,889 $16,444 
(1)    The significant expense categories and amounts align with the segment level information that is regularly provided to the chief operating decision maker.
(2)    Human health-related research and development expenses incurred by Merck Research Laboratories are not allocated to segment profits as noted below.
(3)    Includes equity (income) loss from affiliates and other miscellaneous non-operating expenses.
Equity Loss from Affiliates and Depreciation Included in Segment Profits
Equity income from affiliates and depreciation included in segment profits is as follows:
PharmaceuticalAnimal HealthTotal
Year Ended December 31, 2024
Equity income from affiliates$144 $ $144 
Depreciation5 256 261 
Year Ended December 31, 2023
Equity income from affiliates$111 $— $111 
Depreciation198 203 
Year Ended December 31, 2022
Equity income from affiliates
$39 $— $39 
Depreciation177 182 
Property, Plant and Equipment, Net by Geographic Area
Property, plant and equipment, net, by geographic area where located is as follows:
December 31202420232022
United States$14,724 $13,915 $12,891 
Europe, Middle East and Africa7,548 7,562 6,993 
Asia Pacific (other than China and Japan)982 1,022 966 
China202 193 207 
Japan143 133 135 
Latin America133 222 225 
Other47 
 $23,779 $23,051 $21,422 
v3.25.0.1
Nature of Operations (Details)
12 Months Ended
Dec. 31, 2024
segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Number of operating segments 2
v3.25.0.1
Summary of Accounting Policies (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Intangible Assets Excluding Goodwill [Line Items]      
Customer discounts $ 13,300 $ 12,500 $ 12,300
Accrual for chargebacks reflected as direct reduction to accounts receivable 293 188  
Accrual for rebates included in accrued and other current liabilities $ 2,200 2,300  
Product return period and expiration 12 months    
Depreciation $ 2,104 1,828 1,824
Advertising and promotion costs $ 2,400 $ 2,300 $ 2,200
Minimum      
Intangible Assets Excluding Goodwill [Line Items]      
Product return period 3 months    
Estimated useful life of intangible assets 2 years    
Minimum | Capitalized Software      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of intangible assets 2 years    
Minimum | Buildings      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of property, plant and equipment 25 years    
Minimum | Machinery, equipment and office furnishings      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of property, plant and equipment 3 years    
Minimum | United States      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms, vaccine sales 30 days    
Minimum | United States | Pharmaceutical      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms 36 days    
Minimum | United States | Animal Health      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms 30 days    
Minimum | Outside of the United States      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms 30 days    
Maximum      
Intangible Assets Excluding Goodwill [Line Items]      
Product return period 6 months    
Estimated useful life of intangible assets 24 years    
Maximum | Capitalized Software      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of intangible assets 10 years    
Maximum | Buildings      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of property, plant and equipment 45 years    
Maximum | Machinery, equipment and office furnishings      
Intangible Assets Excluding Goodwill [Line Items]      
Estimated useful life of property, plant and equipment 15 years    
Maximum | United States      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms 90 days    
Payment terms, vaccine sales 60 days    
Maximum | Outside of the United States      
Intangible Assets Excluding Goodwill [Line Items]      
Payment terms 90 days    
v3.25.0.1
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements - Narrative (Details)
$ in Millions
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 02, 2021
Dec. 31, 2024
USD ($)
jurisdiction
Sep. 30, 2024
USD ($)
Jul. 31, 2024
USD ($)
candidate
aqua_facility
Mar. 31, 2024
USD ($)
Jun. 30, 2023
USD ($)
Jan. 31, 2023
USD ($)
Oct. 31, 2022
USD ($)
Aug. 31, 2022
USD ($)
Jul. 31, 2022
USD ($)
May 31, 2022
USD ($)
Mar. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
jurisdiction
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
jurisdiction
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
Apr. 30, 2024
candidate
Oct. 31, 2023
USD ($)
antibodyDrugConjugate
candidate
Feb. 28, 2023
USD ($)
candidate
Business Acquisition [Line Items]                                        
Research and development                             $ 17,938 $ 30,531 $ 13,548      
Sales                             64,168 60,115 59,283      
Cost of sales                             15,193 16,126 17,411      
Other current assets   $ 8,706                     $ 8,706   8,706 8,368        
Accrued and other current liabilities   15,694                     15,694   15,694 15,766        
Forecast | Subsequent Event                                        
Business Acquisition [Line Items]                                        
Contingent consideration                       $ 440                
Royalty Pharma                                        
Business Acquisition [Line Items]                                        
Compensation earned on arragement               $ 50                        
Related Party                                        
Business Acquisition [Line Items]                                        
Other current assets   330                     330   330 632        
Accrued and other current liabilities   $ 113                     $ 113   113 598        
Manufacturing and supply agreements | Related Party                                        
Business Acquisition [Line Items]                                        
Sales                             392 394 383      
Cost of sales                             $ 390 422 404      
Minimum | Manufacturing and supply agreements | Related Party                                        
Business Acquisition [Line Items]                                        
Period of continuing involvement after disposal 4 years                                      
Maximum | Manufacturing and supply agreements | Related Party                                        
Business Acquisition [Line Items]                                        
Period of continuing involvement after disposal 10 years                                      
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff | Organon & Co.                                        
Business Acquisition [Line Items]                                        
Number of jurisdictions under interim operating agreement | jurisdiction   1                     1   1          
Orion                                        
Business Acquisition [Line Items]                                        
Eligible future contingent development-related payments (up to)       $ 30                                
Aggregate, regulatory milestones payments, maximum       625                                
Sales milestone payments       $ 975                                
Orion | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement                                        
Business Acquisition [Line Items]                                        
Upfront payment made to collaborative partner                   $ 290                    
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement                                        
Business Acquisition [Line Items]                                        
Research and development                             $ 351 5,549        
Number of antibody drug conjugates obtained right and obligations | antibodyDrugConjugate                                     3  
Accrued and other current liabilities   $ 817                     $ 817   817 800        
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement                                        
Business Acquisition [Line Items]                                        
Eligible future contingent development-related payments (up to)                                     $ 540  
Aggregate, regulatory milestones payments, maximum                                     1,500  
Sales milestone payments                     $ 780               $ 3,100  
Number of antibody drug conjugates | candidate                                       7
Upfront payment made to collaborative partner                                       $ 175
Number of antibody drug conjugates terminated | candidate                                   1 2  
Number of exercised license option antibody drug conjugates | candidate       1                                
Number of licensed antibody drug conjugates | candidate       3                                
Number of unexercised license option antibody drug conjugates | candidate       1                                
Payment resulting from the license option exercise       $ 38                                
Stock investment in counterparty             $ 100                          
Option payment made to collaborative partner                     30                  
Milestone payment to be made to a collaborative partner                               25        
Contingent developmental milestone payments                             90          
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | First Commercial Sale Milestones                                        
Business Acquisition [Line Items]                                        
Sales milestone payments                     $ 290                  
Orna Therapeutics | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement                                        
Business Acquisition [Line Items]                                        
Eligible future contingent development-related payments (up to)                 $ 440                      
Aggregate, regulatory milestones payments, maximum                 675                      
Sales milestone payments                 2,400                      
Preferred stock investment in counterparty                                 $ 100      
Upfront payment made to collaborative partner                 $ 150                      
Elanco Animal Health Incorporated Aqua Business                                        
Business Acquisition [Line Items]                                        
Cash paid for acquisition of business       $ 1,300                                
Aqua manufacturing facilities | aqua_facility       2                                
LM-299, LaNova Medicines Ltd                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition   588                                    
Maximum aggregate sales-based milestone payments   1,400                     1,400   1,400          
Future contingent developmental milestone payments (up to)   140                     140   140          
Future regulatory milestone payments (up to)   860                     860   860          
LM-299, LaNova Medicines Ltd | Forecast                                        
Business Acquisition [Line Items]                                        
Contingent consideration dependent upon technology transfer                           $ 300            
CN201, Curon Biopharmaceutical                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition     $ 700                                  
Future contingent developmental milestone payments (up to)     300                                  
Future regulatory milestone payments (up to)     300                                  
Research and development                             750          
CN201, Curon Biopharmaceutical | Third-Party                                        
Business Acquisition [Line Items]                                        
Aggregate contingent developmental, regulatory, and sales-based-related payments     $ 128                                  
Eyebiotech Limited                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition       $ 1,200                                
Maximum aggregate sales-based milestone payments       500                                
Future contingent developmental milestone payments (up to)       200                                
Future regulatory milestone payments (up to)       1,000                                
Research and development                             1,350          
Transaction costs       207                                
Developmental milestone payment triggered and paid                         100              
Net assets acquired       $ 21                                
Harpoon Therapeutics, Inc.                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition         $ 765                              
Research and development                             656          
Transaction costs         56                              
Net assets acquired         $ 165                              
Prometheus Biosciences, Inc.                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition           $ 11,000                            
Research and development                               10,200        
Net assets acquired           877                            
Consideration transferred, to settle share-based equity awards           1,200                            
Consideration transferred, to settle equity awards, unvested           700                            
Cash recorded for asset acquisition           368                            
Investments recorded for asset acquisition           296                            
Deferred tax assets recorded for asset acquisition           218                            
Other net liabilities recorded for asset acquisition           $ 5                            
Imago BioSciences, Inc.                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition             1,350                          
Research and development                               $ 1,200        
Transaction costs             60                          
Net assets acquired             $ 219                          
HS-10535 Hansoh Pharma                                        
Business Acquisition [Line Items]                                        
Consideration transferred, asset acquisition   112                                    
Maximum aggregate sales-based milestone payments   1,470                     1,470   1,470          
Future contingent developmental milestone payments (up to)   115                     115   115          
Future regulatory milestone payments (up to)   $ 315                     $ 315   $ 315          
v3.25.0.1
Acquisitions, Divestitures, Research Collaborations and Licensing Agreements - Estimated Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Jul. 09, 2024
Dec. 31, 2023
Dec. 31, 2022
Business Acquisition [Line Items]        
Goodwill $ 21,668   $ 21,197 $ 21,204
Elanco Animal Health Incorporated Aqua Business        
Business Acquisition [Line Items]        
Inventories   $ 65    
Property, plant and equipment   66    
Other assets and liabilities, net   23    
Total identifiable net assets   785    
Goodwill   518    
Consideration transferred   $ 1,303    
Discount rate   8.50%    
Elanco Animal Health Incorporated Aqua Business | Product Rights - Clynay        
Business Acquisition [Line Items]        
Product rights and other   $ 340    
Estimated useful life of intangible assets   15 years    
Elanco Animal Health Incorporated Aqua Business | Other Product Rights        
Business Acquisition [Line Items]        
Product rights and other   $ 291    
Estimated useful life of intangible assets   15 years    
v3.25.0.1
Collaborative Arrangements - AstraZeneca PLC - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Amortization expense for intangible assets $ 2,400 $ 2,000 $ 2,100
Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 3,091 3,212  
Koselugo | Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 49    
Lynparza | Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 1,200    
AstraZeneca      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Amortization expense for intangible assets 48   250
AstraZeneca | Koselugo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Probable contingent payments 100    
Liabilities 100    
AstraZeneca | Lynparza | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Milestone payments sales-based     400
Probable contingent payments     600
Liabilities     600
Sales milestone payments 2,000    
Regulatory milestone payments $ 245 $ 105 $ 250
v3.25.0.1
Collaborative Arrangements - AstraZeneca PLC (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Collaborative Arrangement, Revenue Not from Contract with Customer, Statement of Income or Comprehensive Income [Extensible Enumeration] Sales Sales Sales
Cost of sales $ 15,193 $ 16,126 $ 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Other current assets 38,782 32,168  
Accrued and other current liabilities 15,694 15,766  
AstraZeneca | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Revenue from collaborative arrangement 1,481 1,296 1,170
Cost of sales 378 311 492
Selling, general and administrative 165 192 185
Research and development 77 79 106
Other current assets 424 341  
Accrued and other current liabilities 713 256  
Other Noncurrent Liabilities 0 600  
AstraZeneca | Alliance revenue - Lynparza | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Revenue from collaborative arrangement 1,311 1,199 1,116
AstraZeneca | Alliance revenue - Koselugo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Revenue from collaborative arrangement $ 170 $ 97 $ 54
v3.25.0.1
Collaborative Arrangements - Eisai Co., Ltd. - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Amortization expense for intangible assets $ 2,400 $ 2,000 $ 2,100
Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 3,091 3,212  
Alliance revenue - Lenvima | Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 442    
Eisai      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Amortization expense for intangible assets   154  
Eisai | Alliance revenue - Lenvima | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Milestone payments sales-based 125 125 600
Probable contingent payments   250  
Liabilities   $ 250  
Sales milestone payments $ 2,300    
Regulatory milestone payments     50
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Milestone payments sales-based     $ 400
v3.25.0.1
Collaborative Arrangements - Eisai Co., Ltd. (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Cost of sales $ 15,193 $ 16,126 $ 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Other current assets 38,782 32,168  
Accrued and other current liabilities 15,694 15,766  
Amortization expense for intangible assets 2,400 2,000 2,100
Eisai      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Amortization expense for intangible assets   154  
Eisai | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Revenue from collaborative arrangement 1,010 960 876
Cost of sales 241 381 212
Selling, general and administrative 159 189 158
Research and development 21 66 $ 136
Other current assets 257 226  
Accrued and other current liabilities $ 0 $ 125  
v3.25.0.1
Collaborative Arrangements - Bayer AG (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
Cost of sales 15,193 16,126 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Other current assets 38,782 32,168  
Accrued and other current liabilities 15,694 15,766  
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Milestone payments sales-based     400
Revenue from collaborative arrangement 415 367 341
Sales 739 658 601
Cost of sales 244 224 210
Selling, general and administrative 111 131 153
Research and development 102 90 75
Other current assets 160 156  
Accrued and other current liabilities 82 80  
Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 3,091 3,212  
Adempas | Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales 287 255 238
Adempas | Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets 372    
Verquvo | Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales 37 $ 36 $ 22
Verquvo | Licenses and other      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Intangible assets $ 42    
v3.25.0.1
Collaborative Arrangements - Ridgeback Biotherapeutics LP (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
Cost of sales 15,193 16,126 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Accrued and other current liabilities 15,694 15,766  
Ridgeback Biotherapeutics LP | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Cost of sales 554 852 3,038
Selling, general and administrative 57 97 147
Research and development 13 60 88
Accrued and other current liabilities 68 113  
Ridgeback Biotherapeutics LP | Lagevrio | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales $ 964 $ 1,428 $ 5,684
v3.25.0.1
Collaborative Arrangements - Daiicho Sankyo - Narrative (Details)
$ in Millions
1 Months Ended 12 Months Ended
Aug. 31, 2024
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
Oct. 31, 2023
USD ($)
antibodyDrugConjugate
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Research and development   $ 17,938 $ 30,531 $ 13,548  
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Number of antibody drug conjugates obtained right and obligations | antibodyDrugConjugate         3
Aggregate upfront payments due upon execution in collaborative arrangement         $ 4,000
Refundable upfront payments         1,000
Maximum aggregate contingent milestone payments, per product         $ 5,500
Research and development   $ 351 5,549    
Royalty percentage         5.00%
Upfront cash payment $ 170        
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Ifinatamab Deruxtecan          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Refundable upfront payments         $ 500
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Refundable upfront payments         500
Aggregate upfront payments due upon lapse of time         750
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan and Ralduotatug Deruxtecan          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Aggregate upfront payments due upon lapse of time     $ 1,500    
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Raludotatug Deruxtecan          
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]          
Aggregate upfront payments due upon lapse of time         $ 750
Liable contracted portion amount of research and development expenses to incur costs for, percentage         75.00%
Liable contracted portion amount of research and development expenses to incur costs for         $ 2,000
v3.25.0.1
Collaborative Arrangements - Daiicho Sankyo (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Selling, general and administrative $ 10,816 $ 10,504 $ 10,042
Research and development 17,938 30,531 13,548
Other current assets 38,782 32,168  
Accrued and other current liabilities 15,694 15,766  
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Selling, general and administrative 26 3  
Research and development 351 5,549  
Other current assets 8 0  
Accrued and other current liabilities 817 800  
Other Noncurrent Liabilities 0 750  
Bayer AG | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Selling, general and administrative 111 131 153
Research and development 102 90 $ 75
Other current assets 160 156  
Accrued and other current liabilities $ 82 $ 80  
v3.25.0.1
Collaborative Arrangements - Moderna, Inc. - Narrative (Details) - Moderna - Collaborative Arrangement, Transaction with Party to Collaborative Arrangement - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]    
Contractual payment $ 250  
Capitalization of shared costs   $ 198
v3.25.0.1
Collaborative Arrangements - Moderna, Inc. (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Selling, general and administrative $ 10,816 $ 10,504 $ 10,042
Research and development 17,938 30,531 13,548
Accrued and other current liabilities 15,694 15,766  
Moderna | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Selling, general and administrative 16 5 0
Research and development 358 218 $ 288
Accrued and other current liabilities $ 57 $ 63  
v3.25.0.1
Collaborative Arrangements - Bristol Meyers Squibb Company - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Bristol Myers Squibb | Licensing Agreements      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Royalty rate, deduction, percentage 50.00%    
Bristol Myers Squibb | Licensing Agreements | Regulatory Milestones      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Proceeds from collaborators     $ 20
Bristol Myers Squibb | Licensing Agreements | Alliance Revenue-Reblozyl      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Sales milestone payments $ 80    
Bristol Myers Squibb | Minimum | Licensing Agreements      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Royalty rate, percentage 20.00%    
Bristol Myers Squibb | Maximum | Licensing Agreements      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Royalty rate, percentage 24.00%    
Bristol Myers Squibb Company | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Revenue from collaborative arrangement $ 371 $ 212 $ 166
v3.25.0.1
Restructuring - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 888 $ 933  
2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Expected restructuring and related cost $ 4,000    
Estimate of cumulative pre tax costs that will be noncash 60.00%    
Total pretax restructuring costs $ 888 190  
Cumulative costs since inception $ 1,100    
2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   $ 743 $ 666
v3.25.0.1
Restructuring - Charges Activities by Type of Cost (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 888 $ 933  
Restructuring Program, 2024 and 2019      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   933  
2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 888 190  
2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   $ 743 $ 666
Cost of sales | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Cost of sales Cost of sales  
Total pretax restructuring costs $ 495 $ 62  
Cost of sales | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Cost of sales Cost of sales
Total pretax restructuring costs   $ 149 $ 205
Selling, general and administrative | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Selling, general and administrative    
Total pretax restructuring costs $ 83    
Selling, general and administrative | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Selling, general and administrative Selling, general and administrative
Total pretax restructuring costs   $ 122 $ 94
Research and development | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Research and development    
Total pretax restructuring costs $ 1    
Research and development | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Research and development Research and development
Total pretax restructuring costs   $ 1 $ 30
Restructuring costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring costs Restructuring costs  
Total pretax restructuring costs $ 309 $ 128  
Restructuring costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Restructuring costs Restructuring costs
Total pretax restructuring costs   $ 471 $ 337
Accelerated Depreciation      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs 254 140  
Accelerated Depreciation | Restructuring Program, 2024 and 2019      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   140  
Accelerated Depreciation | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 254 0  
Accelerated Depreciation | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   $ 140 $ 120
Accelerated Depreciation | Cost of sales | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Cost of sales Cost of sales  
Total pretax restructuring costs $ 254 $ 0  
Accelerated Depreciation | Cost of sales | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Cost of sales Cost of sales
Total pretax restructuring costs   $ 131 $ 72
Accelerated Depreciation | Selling, general and administrative | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Selling, general and administrative    
Total pretax restructuring costs $ 0    
Accelerated Depreciation | Selling, general and administrative | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Selling, general and administrative Selling, general and administrative
Total pretax restructuring costs   $ 9 $ 19
Accelerated Depreciation | Research and development | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Research and development    
Total pretax restructuring costs $ 0    
Accelerated Depreciation | Research and development | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Research and development Research and development
Total pretax restructuring costs   $ 0 $ 29
Accelerated Depreciation | Restructuring costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring costs Restructuring costs  
Total pretax restructuring costs $ 0 $ 0  
Accelerated Depreciation | Restructuring costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Restructuring costs Restructuring costs
Total pretax restructuring costs   $ 0 $ 0
Separation Costs      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs 122 454  
Separation Costs | Restructuring Program, 2024 and 2019      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   454  
Separation Costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 122 115  
Separation Costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   $ 339 $ 212
Separation Costs | Cost of sales | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Cost of sales Cost of sales  
Total pretax restructuring costs $ 0 $ 0  
Separation Costs | Cost of sales | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Cost of sales Cost of sales
Total pretax restructuring costs   $ 0 $ 0
Separation Costs | Selling, general and administrative | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Selling, general and administrative    
Total pretax restructuring costs $ 0    
Separation Costs | Selling, general and administrative | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Selling, general and administrative Selling, general and administrative
Total pretax restructuring costs   $ 0 $ 0
Separation Costs | Research and development | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Research and development    
Total pretax restructuring costs $ 0    
Separation Costs | Research and development | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Research and development Research and development
Total pretax restructuring costs   $ 0 $ 0
Separation Costs | Restructuring costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring costs Restructuring costs  
Total pretax restructuring costs $ 122 $ 115  
Separation Costs | Restructuring costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Restructuring costs Restructuring costs
Total pretax restructuring costs   $ 339 $ 212
Other Exit Costs      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs 512 339  
Other Exit Costs | Restructuring Program, 2024 and 2019      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   339  
Other Exit Costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs $ 512 75  
Other Exit Costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Total pretax restructuring costs   $ 264 $ 334
Other Exit Costs | Cost of sales | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Cost of sales Cost of sales  
Total pretax restructuring costs $ 241 $ 62  
Other Exit Costs | Cost of sales | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Cost of sales Cost of sales
Total pretax restructuring costs   $ 18 $ 133
Other Exit Costs | Selling, general and administrative | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Selling, general and administrative    
Total pretax restructuring costs $ 83    
Other Exit Costs | Selling, general and administrative | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Selling, general and administrative Selling, general and administrative
Total pretax restructuring costs   $ 113 $ 75
Other Exit Costs | Research and development | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Research and development    
Total pretax restructuring costs $ 1    
Other Exit Costs | Research and development | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Research and development Research and development
Total pretax restructuring costs   $ 1 $ 1
Other Exit Costs | Restructuring costs | 2024 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration] Restructuring costs Restructuring costs  
Total pretax restructuring costs $ 187 $ 13  
Other Exit Costs | Restructuring costs | 2019 Restructuring Program      
Restructuring Cost and Reserve [Line Items]      
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]   Restructuring costs Restructuring costs
Total pretax restructuring costs   $ 132 $ 125
v3.25.0.1
Restructuring - Activities by Program (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Restructuring Reserve [Roll Forward]    
Restructuring reserve, beginning balance $ 712 $ 513
Expenses 888 933
(Payments) receipts, net (445) (410)
Non-cash activity (591) (324)
Restructuring reserve, ending balance 564 712
Separation Costs    
Restructuring Reserve [Roll Forward]    
Restructuring reserve, beginning balance 681 479
Expenses 122 454
(Payments) receipts, net (239) (252)
Non-cash activity 0 0
Restructuring reserve, ending balance 564 681
Accelerated Depreciation    
Restructuring Reserve [Roll Forward]    
Restructuring reserve, beginning balance 0 0
Expenses 254 140
(Payments) receipts, net 0 0
Non-cash activity (254) (140)
Restructuring reserve, ending balance 0 0
Other Exit Costs    
Restructuring Reserve [Roll Forward]    
Restructuring reserve, beginning balance 31 34
Expenses 512 339
(Payments) receipts, net (206) (158)
Non-cash activity (337) (184)
Restructuring reserve, ending balance $ 0 $ 31
v3.25.0.1
Financial Instruments - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Jan. 31, 2025
Derivative [Line Items]        
Total Swap Notional Amount $ 38,560 $ 30,551    
Pretax net unrealized losses on derivatives maturing within the next 12 months estimated to be reclassified from AOCI to sales (262)      
Equity investments without readily determinable fair values 863 832    
Unrealized gains recognized on investments in equity securities without readily determinable fair value 19 10    
Unrealized losses recognized on investments in equity securities without readily determinable fair values 51 61    
Cumulative upward price adjustment 309      
Cumulative downward price adjustment 107      
(Income) loss from investments in equity securities, net (14) (340) $ 1,419  
Payments of contingent consideration 151 117    
Fair value of loans payable and long-term debt, including current portion 32,600 32,000    
Debt, carrying amount 37,100 35,100    
Factored accounts receivable 2,100 3,000    
Cash collateral received from counterparties $ 165 3    
5.00% notes due 2053        
Derivative [Line Items]        
Stated interest rate 5.00%      
Senior Notes | Subsequent Event | 5.00% notes due 2053        
Derivative [Line Items]        
Stated interest rate       5.00%
Interest rate swap contracts | 5.00% notes due 2053 | Subsequent Event        
Derivative [Line Items]        
Total Swap Notional Amount       $ 250
Lyfnua        
Derivative [Line Items]        
Payments of contingent consideration $ 25      
Sanofi Pasteur        
Derivative [Line Items]        
Payments of contingent consideration 126      
Equity Funds        
Derivative [Line Items]        
Equity securities held through ownership interests in investment funds 267 417 598  
(Income) loss from investments in equity securities, net 29 106 $ 1,000  
Accounts Receivable Factoring Collections        
Derivative [Line Items]        
Funds collected from factoring of receivable, held in restricted cash $ 55 44    
Customer Concentration Risk | Accounts Receivable | McKesson Corporation        
Derivative [Line Items]        
Percentage of accounts receivable represented by customers with largest balances 21.00%      
Customer Concentration Risk | Accounts Receivable | Cencora, Inc.        
Derivative [Line Items]        
Percentage of accounts receivable represented by customers with largest balances 21.00%      
Customer Concentration Risk | Accounts Receivable | Cardinal Health, Inc.        
Derivative [Line Items]        
Percentage of accounts receivable represented by customers with largest balances 13.00%      
Level 2        
Derivative [Line Items]        
Cash equivalents $ 12,300 6,000    
Derivatives Designated as Hedging Instruments        
Derivative [Line Items]        
Total Swap Notional Amount 12,465 12,754    
Derivatives Not Designated as Hedging Instruments        
Derivative [Line Items]        
Total Swap Notional Amount $ 26,095 $ 17,797    
Maximum | Derivatives Designated as Hedging Instruments        
Derivative [Line Items]        
Term of derivative contract 2 years      
Maximum | Derivatives Not Designated as Hedging Instruments        
Derivative [Line Items]        
Maximum planning cycle of hedges (less than) 6 months      
v3.25.0.1
Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Foreign exchange contracts      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income $ (30) $ 0 $ (48)
Foreign exchange contracts | Other (income) expense, net      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing (4) 1 (1)
Euro-denominated notes      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income (192) 105 (162)
Euro-denominated notes | Other (income) expense, net      
Derivative Instruments and Hedging Activities Disclosures [Line Items]      
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing $ 0 $ 0 $ 0
v3.25.0.1
Financial Instruments - Summary of Interest Rate Swaps Held (Details)
Jan. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
interest_rate_swap
May 31, 2024
EUR (€)
Dec. 31, 2023
USD ($)
May 31, 2023
Derivative [Line Items]          
Total Swap Notional Amount   $ 38,560,000,000   $ 30,551,000,000  
4.50% notes due 2033          
Derivative [Line Items]          
Stated interest rate   4.50%      
Senior Notes          
Derivative [Line Items]          
Par Value of Debt | €     € 3,400,000,000    
Senior Notes | 4.50% notes due 2033          
Derivative [Line Items]          
Stated interest rate         4.50%
Interest rate swap contracts | 4.50% notes due 2033          
Derivative [Line Items]          
Par Value of Debt   $ 1,500,000,000      
Number of Interest Rate Swaps Held | interest_rate_swap   6      
Total Swap Notional Amount   $ 1,500,000,000      
Interest rate swap contracts | 5.00% notes due 2053 | Subsequent Event          
Derivative [Line Items]          
Total Swap Notional Amount $ 250,000,000        
v3.25.0.1
Financial Instruments - Amounts Recorded on Balance Sheet Related to Fair Value Hedges (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]    
Hedged Liability, Statement of Financial Position [Extensible Enumeration] Long-Term Debt Long-Term Debt
Carrying Amount of Hedged Liabilities $ 1,509 $ 1,056
Cumulative Amount of Fair Value Hedging Adjustment Increase Included in the Carrying Amount $ 17 $ 56
v3.25.0.1
Financial Instruments - Fair Value of Derivatives Segregated between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Derivatives, Fair Value [Line Items]    
Fair value of derivative, asset $ 729 $ 342
Fair value of derivative, liability 345 239
U.S dollar notional amount 38,560 30,551
Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Fair value of derivative, asset 406 189
Fair value of derivative, liability 2 77
U.S dollar notional amount 12,465 12,754
Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Fair value of derivative, asset 323 153
Fair value of derivative, liability 343 162
U.S dollar notional amount $ 26,095 $ 17,797
Interest rate swap contracts | Derivatives Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other Assets Other Assets
Fair value of derivative, asset $ 17 $ 57
Derivative asset, notional amount $ 1,500 $ 1,000
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other current assets    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other current assets Other current assets
Fair value of derivative, asset $ 323 $ 106
Derivative asset, notional amount $ 8,662 $ 6,138
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other Assets    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other Assets Other Assets
Fair value of derivative, asset $ 66 $ 26
Derivative asset, notional amount $ 2,125 $ 1,929
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Accrued and other current liabilities    
Derivatives, Fair Value [Line Items]    
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Accrued and other current liabilities Accrued and other current liabilities
Fair value of derivative, liability $ 1 $ 76
Derivative liability, notional amount $ 162 $ 3,680
Foreign exchange contracts | Derivatives Designated as Hedging Instruments | Other Noncurrent Liabilities    
Derivatives, Fair Value [Line Items]    
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Other Noncurrent Liabilities Other Noncurrent Liabilities
Fair value of derivative, liability $ 1 $ 1
Derivative liability, notional amount $ 16 $ 7
Foreign exchange contracts | Derivatives Not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other current assets Other current assets
Fair value of derivative, asset $ 323 $ 153
Derivative asset, notional amount $ 12,544 $ 9,693
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Accrued and other current liabilities Accrued and other current liabilities
Fair value of derivative, liability $ 343 $ 162
Derivative liability, notional amount $ 13,551 $ 8,104
v3.25.0.1
Financial Instruments - Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]    
Gross amounts recognized in the consolidated balance sheet, asset $ 729 $ 342
Gross amount subject to offset in master netting arrangements not offset in the condensed balance sheet, asset (299) (215)
Cash collateral received/posted, asset (165) (3)
Net amounts, asset 265 124
Gross amounts recognized in the consolidated balance sheet, liability 345 239
Gross amount subject to offset in master netting arrangements not offset in the condensed balance sheet, liability (299) (215)
Cash collateral received/posted, liability 0 0
Net amounts, liability $ 46 $ 24
v3.25.0.1
Financial Instruments - Location and Pretax (Gains) or Loss Amounts for Derivatives (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
Other (income) expense, net (24) 466 1,501
Other comprehensive income (loss) $ 216 $ (393) $ (339)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Other (income) expense, net Other (income) expense, net Other (income) expense, net
Foreign exchange contracts      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of gain recognized in OCI on derivatives $ 508 $ 114 $ 684
Increase in Sales as a result of AOCL reclassifications (167) (249) (773)
Interest rate swap contracts      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of gain recognized in OCI on derivatives (1) 13 (2)
Amount of gain recognized in Other (income) expense, net on derivatives (1) (1) (2)
Other (income) expense, net | Interest rate swap contracts      
Derivative Instruments, Gain (Loss) [Line Items]      
Hedged items (39) 56 (13)
Derivatives designated as hedging instruments 39 (57) 4
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest | Foreign exchange contracts      
Derivative Instruments, Gain (Loss) [Line Items]      
Sales $ 167 $ 249 $ 773
v3.25.0.1
Financial Instruments - Income Statement Effects on Derivatives Not Designated as Hedging Instruments (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Currency Swap | Other (income) expense, net      
Derivative [Line Items]      
Amount of Derivative Pretax Loss (Gain) Recognized in Income $ 251 $ (6) $ (49)
Foreign Exchange Future | Sales      
Derivative [Line Items]      
Amount of Derivative Pretax Loss (Gain) Recognized in Income $ (28) $ 5 $ (37)
v3.25.0.1
Financial Instruments - Information on Debt and Equity Securities (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]    
Debt securities, amortized cost $ 536 $ 337
Debt securities, gross unrealized gains 0 0
Debt securities, gross unrealized losses 0 0
Debt securities, fair value 536 337
Equity securities 920 764
Total debt and publicly traded equity securities, fair value 1,456 1,101
Unrealized net gains (losses) (30) 411
Commercial paper    
Debt Securities, Available-for-sale [Line Items]    
Debt securities, amortized cost 348 252
Debt securities, gross unrealized gains 0 0
Debt securities, gross unrealized losses 0 0
Debt securities, fair value 348 252
U.S. government and agency securities    
Debt Securities, Available-for-sale [Line Items]    
Debt securities, amortized cost 188 72
Debt securities, gross unrealized gains 0 0
Debt securities, gross unrealized losses 0 0
Debt securities, fair value 188 72
Corporate notes and bonds    
Debt Securities, Available-for-sale [Line Items]    
Debt securities, amortized cost 0 13
Debt securities, gross unrealized gains 0 0
Debt securities, gross unrealized losses 0 0
Debt securities, fair value $ 0 $ 13
v3.25.0.1
Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Assets      
Investments $ 536 $ 337  
Equity securities 920 764  
Other Assets 16,044 11,996  
Fair value of derivative, asset 729 342  
Liabilities      
Contingent consideration 193 354 $ 456
Fair value of derivative, liability 345 239  
Commercial paper      
Assets      
Investments 348 252  
U.S. government and agency securities      
Assets      
Investments 188 72  
Corporate notes and bonds      
Assets      
Investments 0 13  
Fair Value, Measurements, Recurring      
Assets      
Investments 910 504  
Other Assets 546 597  
Fair value of derivative, asset 729 342  
Total assets 2,185 1,443  
Liabilities      
Contingent consideration 193 354  
Fair value of derivative, liability 345 239  
Total liabilities 538 593  
Fair Value, Measurements, Recurring | Foreign exchange contracts      
Assets      
Fair value of derivative, asset 499 202  
Liabilities      
Fair value of derivative, liability 338 239  
Fair Value, Measurements, Recurring | Currency Options      
Assets      
Fair value of derivative, asset 213 83  
Liabilities      
Fair value of derivative, liability 7 0  
Fair Value, Measurements, Recurring | Interest rate swap contracts      
Assets      
Fair value of derivative, asset 17 57  
Fair Value, Measurements, Recurring | Commercial paper      
Assets      
Investments 348 252  
Fair Value, Measurements, Recurring | Publicly traded equity securities      
Assets      
Equity securities 463 252  
Publicly traded equity securities 457 512  
Fair Value, Measurements, Recurring | U.S. government and agency securities      
Assets      
Available-for-sale debt securities included in Short-term investments 99 0  
Debt securities, available-for-sale, noncurrent 89 72  
Fair Value, Measurements, Recurring | Corporate notes and bonds      
Assets      
Debt securities, available-for-sale, noncurrent 0 13  
Fair Value, Measurements, Recurring | Level 1      
Assets      
Investments 463 252  
Other Assets 546 597  
Fair value of derivative, asset 0 0  
Total assets 1,009 849  
Liabilities      
Contingent consideration 0 0  
Fair value of derivative, liability 0 0  
Total liabilities 0 0  
Fair Value, Measurements, Recurring | Level 1 | Foreign exchange contracts      
Assets      
Fair value of derivative, asset 0 0  
Liabilities      
Fair value of derivative, liability 0 0  
Fair Value, Measurements, Recurring | Level 1 | Currency Options      
Assets      
Fair value of derivative, asset 0 0  
Liabilities      
Fair value of derivative, liability 0 0  
Fair Value, Measurements, Recurring | Level 1 | Interest rate swap contracts      
Assets      
Fair value of derivative, asset 0 0  
Fair Value, Measurements, Recurring | Level 1 | Commercial paper      
Assets      
Investments 0 0  
Fair Value, Measurements, Recurring | Level 1 | Publicly traded equity securities      
Assets      
Equity securities 463 252  
Publicly traded equity securities 457 512  
Liabilities      
Securities, fair value, which are subject to a contractual sale restriction 81 177  
Fair Value, Measurements, Recurring | Level 1 | U.S. government and agency securities      
Assets      
Available-for-sale debt securities included in Short-term investments 0 0  
Debt securities, available-for-sale, noncurrent 89 72  
Fair Value, Measurements, Recurring | Level 1 | Corporate notes and bonds      
Assets      
Debt securities, available-for-sale, noncurrent 0 13  
Fair Value, Measurements, Recurring | Level 2      
Assets      
Investments 447 252  
Other Assets 0 0  
Fair value of derivative, asset 729 342  
Total assets 1,176 594  
Liabilities      
Contingent consideration 0 0  
Fair value of derivative, liability 345 239  
Total liabilities 345 239  
Fair Value, Measurements, Recurring | Level 2 | Foreign exchange contracts      
Assets      
Fair value of derivative, asset 499 202  
Liabilities      
Fair value of derivative, liability 338 239  
Fair Value, Measurements, Recurring | Level 2 | Currency Options      
Assets      
Fair value of derivative, asset 213 83  
Liabilities      
Fair value of derivative, liability 7 0  
Fair Value, Measurements, Recurring | Level 2 | Interest rate swap contracts      
Assets      
Fair value of derivative, asset 17 57  
Fair Value, Measurements, Recurring | Level 2 | Commercial paper      
Assets      
Investments 348 252  
Fair Value, Measurements, Recurring | Level 2 | Publicly traded equity securities      
Assets      
Equity securities 0 0  
Publicly traded equity securities 0 0  
Fair Value, Measurements, Recurring | Level 2 | U.S. government and agency securities      
Assets      
Available-for-sale debt securities included in Short-term investments 99 0  
Debt securities, available-for-sale, noncurrent 0 0  
Fair Value, Measurements, Recurring | Level 2 | Corporate notes and bonds      
Assets      
Debt securities, available-for-sale, noncurrent 0 0  
Fair Value, Measurements, Recurring | Level 3      
Assets      
Investments 0 0  
Other Assets 0 0  
Fair value of derivative, asset 0 0  
Total assets 0 0  
Liabilities      
Contingent consideration 193 354  
Fair value of derivative, liability 0 0  
Total liabilities 193 354  
Fair Value, Measurements, Recurring | Level 3 | Foreign exchange contracts      
Assets      
Fair value of derivative, asset 0 0  
Liabilities      
Fair value of derivative, liability 0 0  
Fair Value, Measurements, Recurring | Level 3 | Currency Options      
Assets      
Fair value of derivative, asset 0 0  
Liabilities      
Fair value of derivative, liability 0 0  
Fair Value, Measurements, Recurring | Level 3 | Interest rate swap contracts      
Assets      
Fair value of derivative, asset 0 0  
Fair Value, Measurements, Recurring | Level 3 | Commercial paper      
Assets      
Investments 0 0  
Fair Value, Measurements, Recurring | Level 3 | Publicly traded equity securities      
Assets      
Equity securities 0 0  
Publicly traded equity securities 0 0  
Fair Value, Measurements, Recurring | Level 3 | U.S. government and agency securities      
Assets      
Available-for-sale debt securities included in Short-term investments 0 0  
Debt securities, available-for-sale, noncurrent 0 0  
Fair Value, Measurements, Recurring | Level 3 | Corporate notes and bonds      
Assets      
Debt securities, available-for-sale, noncurrent $ 0 $ 0  
v3.25.0.1
Financial Instruments - Information About Changes in Liabilities for Contingent Consideration (Details)
$ in Millions
12 Months Ended
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Contingent consideration, beginning balance $ 354 $ 456
Changes in estimated fair value (10) 15
Payments (151) (117)
Contingent consideration, ending balance 193 $ 354
Contingent consideration, liability, current 148  
Sanofi Pasteur    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Payments (126)  
Contingent consideration, liability, current $ 123  
Contingent consideration, measurement input, discount rate 0.115  
v3.25.0.1
Inventories - Inventories (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Inventory Disclosure [Abstract]    
Finished goods $ 2,022 $ 1,954
Raw materials and work in process 8,831 8,037
Supplies 289 277
Total 11,142 10,268
Decrease to LIFO cost (840) (562)
Total current and noncurrent inventories 10,302 9,706
Recognized as:    
Inventories 6,109 6,358
Other Assets $ 4,193 $ 3,348
v3.25.0.1
Inventories - Narrative (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Inventory [Line Items]    
LIFO inventory amount $ 3,400 $ 3,100
Inventory classified in Other assets 4,193 3,348
Inventory Not Expected to be Sold Within One Year    
Inventory [Line Items]    
Inventory classified in Other assets 3,800 2,600
Inventories Produced in Preparation for Product Launches    
Inventory [Line Items]    
Inventory classified in Other assets $ 412 $ 790
v3.25.0.1
Goodwill and Other Intangibles - Goodwill Activity by Segment (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Goodwill [Roll Forward]    
Goodwill, beginning balance $ 21,197 $ 21,204
Acquisitions 518  
Other (47) (7)
Goodwill, ending balance 21,668 21,197
Accumulated goodwill impairment losses 531 531
Pharmaceutical    
Goodwill [Roll Forward]    
Goodwill, beginning balance 17,922 17,936
Acquisitions 0  
Other (19) (14)
Goodwill, ending balance 17,903 17,922
Animal Health    
Goodwill [Roll Forward]    
Goodwill, beginning balance 3,275 3,268
Acquisitions 518  
Other (28) 7
Goodwill, ending balance $ 3,765 $ 3,275
v3.25.0.1
Goodwill and Other Intangibles - Other Intangibles (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Intangible Assets Excluding Goodwill [Line Items]    
Intangible assets, gross carrying amount $ 42,162 $ 41,603
Accumulated amortization 25,792 23,592
Intangible assets, net 16,370 18,011
IPR&D    
Intangible Assets Excluding Goodwill [Line Items]    
Indefinite-lived intangible assets 430 6,816
Product rights    
Intangible Assets Excluding Goodwill [Line Items]    
Finite-lived intangible assets, gross carrying amount 29,988 23,643
Accumulated amortization 19,066 17,765
Finite-lived intangible assets, net 10,922 5,878
Trade names    
Intangible Assets Excluding Goodwill [Line Items]    
Finite-lived intangible assets, gross carrying amount 2,881 2,881
Accumulated amortization 954 776
Finite-lived intangible assets, net 1,927 2,105
Licenses and other    
Intangible Assets Excluding Goodwill [Line Items]    
Finite-lived intangible assets, gross carrying amount 8,863 8,263
Accumulated amortization 5,772 5,051
Finite-lived intangible assets, net $ 3,091 $ 3,212
v3.25.0.1
Goodwill and Other Intangibles - Narrative (Details) - USD ($)
$ in Millions
1 Months Ended 3 Months Ended 12 Months Ended
Dec. 31, 2022
Sep. 30, 2022
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Intangible Assets Excluding Goodwill [Line Items]          
Other intangibles, net     $ 16,370 $ 18,011  
Intangible asset impairment charges     39 $ 792 $ 1,749
Impairment, Intangible Asset, Indefinite-Lived (Excluding Goodwill), Statement of Income or Comprehensive Income [Extensible Enumeration]       Research and development Research and development
Impairment, Intangible Asset, Finite-Lived, Statement of Income or Comprehensive Income [Extensible Enumeration]         Research and development
Amortization expense for intangible assets     2,400 $ 2,000 $ 2,100
Estimated aggregate amortization expense, 2025     2,400    
Estimated aggregate amortization expense, 2026     2,300    
Estimated aggregate amortization expense, 2027     2,100    
Estimated aggregate amortization expense, 2028     1,800    
Estimated aggregate amortization expense, 2029     1,500    
IPR&D          
Intangible Assets Excluding Goodwill [Line Items]          
IPR&D intangible asset     430 6,816  
Animal Health          
Intangible Assets Excluding Goodwill [Line Items]          
Other intangibles, net     4,300    
gefapixant | IPR&D          
Intangible Assets Excluding Goodwill [Line Items]          
IPR&D impairment charges       779  
Lyfnua          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     21    
nemtabrutinib | IPR&D          
Intangible Assets Excluding Goodwill [Line Items]          
IPR&D intangible asset     418    
IPR&D impairment charges $ 780 $ 807     1,600
Product rights          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     10,922 5,878  
Product rights | Reblozyl          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     2,800    
Product rights | Zerbaxa          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     260    
Product rights | Animal Health          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     1,700    
Product rights | Winrevair          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     5,900    
Trade names          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     1,927 2,105  
Trade names | Animal Health          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     1,900    
Licenses and other          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     3,091 $ 3,212  
Licenses and other | Lynparza          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     1,200    
Licenses and other | Lenvima          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     442    
Licenses and other | Adempas          
Intangible Assets Excluding Goodwill [Line Items]          
Finite-lived intangible assets, net     $ 372    
Licenses and other | derazantinib          
Intangible Assets Excluding Goodwill [Line Items]          
Intangible asset impairment charge related to finite-lived intangible asset         $ 80
v3.25.0.1
Loans Payable, Long-Term Debt and Leases - Narrative (Details)
$ in Millions
12 Months Ended
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
May 31, 2024
EUR (€)
Debt Instrument [Line Items]        
Long-term debt, current maturities $ 2,500 $ 1,300    
Loans payable and current portion of long-term debt 2,649 $ 1,372    
Long-term debt, maturities, repayments of principal in 2025 2,600      
Long-term debt, maturities, repayments of principal in 2026 2,200      
Long-term debt, maturities, repayments of principal in 2027 1,500      
Long-term debt, maturities, repayments of principal in 2028 2,100      
Long-term debt, maturities, repayments of principal in 2029 1,700      
Long-term debt, interest payments in 2025 1,200      
Long-term debt, interest payments in 2026 1,200      
Long-term debt, interest payments in 2027 1,100      
Long-term debt, interest payments in 2028 1,100      
Long-term debt, interest payments in 2029 1,000      
Available borrowing capacity under credit facility $ 6,000      
Operating lease, weighted average remaining lease term 6 years 7 years    
Operating lease, cost $ 348 $ 339 $ 334  
Operating lease, payments 357 347 335  
Right-of-use asset obtained in exchange for operating lease liability 47 $ 122 $ 57  
Lessee, operating lease, lease not yet commenced, amount $ 183      
Buildings        
Debt Instrument [Line Items]        
Operating lease, weighted average remaining lease term 6 years      
Lessee, operating lease, renewal term 5 years      
Vehicles        
Debt Instrument [Line Items]        
Operating lease, weighted average remaining lease term 4 years      
Senior Notes        
Debt Instrument [Line Items]        
Face amount of debt | €       € 3,400,000,000
Other Variable Rate Debt        
Debt Instrument [Line Items]        
Effective interest rate 5.02% 4.82%    
6.30% debentures due 2026        
Debt Instrument [Line Items]        
Stated interest rate 6.30%      
3.25% Notes due 2032 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate       3.25%
Face amount of debt | €       € 850,000,000
3.50% Notes due 2037 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate       3.50%
Face amount of debt | €       € 850,000,000
3.70% Notes due 2044 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate       3.70%
Face amount of debt | €       € 850,000,000
3.75% Notes due 2054 | Senior Notes        
Debt Instrument [Line Items]        
Stated interest rate       3.75%
Face amount of debt | €       € 850,000,000
Notes Subject To Repayment At Option Of Holder        
Debt Instrument [Line Items]        
Loans payable and current portion of long-term debt $ 149 $ 69    
Commercial paper        
Debt Instrument [Line Items]        
Weighted-average interest rate of commercial paper 5.18% 5.14%    
v3.25.0.1
Loans Payable, Long-Term Debt and Leases - Long-Term Debt (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Debt Instrument [Line Items]    
Long-Term Debt $ 34,462 $ 33,683
2.15% notes due 2031    
Debt Instrument [Line Items]    
Stated interest rate 2.15%  
Long-Term Debt $ 1,989 1,988
2.75% notes due 2051    
Debt Instrument [Line Items]    
Stated interest rate 2.75%  
Long-Term Debt $ 1,980 1,980
3.70% notes due 2045    
Debt Instrument [Line Items]    
Stated interest rate 3.70%  
Long-Term Debt $ 1,980 1,979
3.40% notes due 2029    
Debt Instrument [Line Items]    
Stated interest rate 3.40%  
Long-Term Debt $ 1,742 1,740
4.50% notes due 2033    
Debt Instrument [Line Items]    
Stated interest rate 4.50%  
Long-Term Debt $ 1,509 1,547
1.70% notes due 2027    
Debt Instrument [Line Items]    
Stated interest rate 1.70%  
Long-Term Debt $ 1,497 1,495
2.90% notes due 2061    
Debt Instrument [Line Items]    
Stated interest rate 2.90%  
Long-Term Debt $ 1,484 1,484
5.00% notes due 2053    
Debt Instrument [Line Items]    
Stated interest rate 5.00%  
Long-Term Debt $ 1,482 1,481
4.00% notes due 2049    
Debt Instrument [Line Items]    
Stated interest rate 4.00%  
Long-Term Debt $ 1,474 1,473
4.15% notes due 2043    
Debt Instrument [Line Items]    
Stated interest rate 4.15%  
Long-Term Debt $ 1,240 1,240
1.45% notes due 2030    
Debt Instrument [Line Items]    
Stated interest rate 1.45%  
Long-Term Debt $ 1,240 1,238
2.45% notes due 2050    
Debt Instrument [Line Items]    
Stated interest rate 2.45%  
Long-Term Debt $ 1,216 1,214
1.875% euro-denominated notes due 2026    
Debt Instrument [Line Items]    
Stated interest rate 1.875%  
Long-Term Debt $ 1,041 1,103
0.75% notes due 2026    
Debt Instrument [Line Items]    
Stated interest rate 0.75%  
Long-Term Debt $ 998 996
1.90% notes due 2028    
Debt Instrument [Line Items]    
Stated interest rate 1.90%  
Long-Term Debt $ 996 995
5.15% notes due 2063    
Debt Instrument [Line Items]    
Stated interest rate 5.15%  
Long-Term Debt $ 987 987
3.90% notes due 2039    
Debt Instrument [Line Items]    
Stated interest rate 3.90%  
Long-Term Debt $ 987 986
2.35% notes due 2040    
Debt Instrument [Line Items]    
Stated interest rate 2.35%  
Long-Term Debt $ 986 985
3.25% euro-denominated notes due 2032    
Debt Instrument [Line Items]    
Stated interest rate 3.25%  
Long-Term Debt $ 880 0
3.50% euro-denominated notes due 2037    
Debt Instrument [Line Items]    
Stated interest rate 3.50%  
Long-Term Debt $ 877 0
3.70% euro-denominated notes due 2044    
Debt Instrument [Line Items]    
Stated interest rate 3.70%  
Long-Term Debt $ 876 0
3.75% euro-denominated notes due 2054    
Debt Instrument [Line Items]    
Stated interest rate 3.75%  
Long-Term Debt $ 873 0
4.30% notes due 2030    
Debt Instrument [Line Items]    
Stated interest rate 4.30%  
Long-Term Debt $ 746 745
4.90% notes due 2044    
Debt Instrument [Line Items]    
Stated interest rate 4.90%  
Long-Term Debt $ 740 740
6.50% notes due 2033    
Debt Instrument [Line Items]    
Stated interest rate 6.50%  
Long-Term Debt $ 702 707
1.375% euro-denominated notes due 2036    
Debt Instrument [Line Items]    
Stated interest rate 1.375%  
Long-Term Debt $ 517 548
2.50% euro-denominated notes due 2034    
Debt Instrument [Line Items]    
Stated interest rate 2.50%  
Long-Term Debt $ 517 548
4.05% notes due 2028    
Debt Instrument [Line Items]    
Stated interest rate 4.05%  
Long-Term Debt $ 498 497
3.60% notes due 2042    
Debt Instrument [Line Items]    
Stated interest rate 3.60%  
Long-Term Debt $ 492 492
6.55% notes due 2037    
Debt Instrument [Line Items]    
Stated interest rate 6.55%  
Long-Term Debt $ 404 406
5.75% notes due 2036    
Debt Instrument [Line Items]    
Stated interest rate 5.75%  
Long-Term Debt $ 339 339
5.95% debentures due 2028    
Debt Instrument [Line Items]    
Stated interest rate 5.95%  
Long-Term Debt $ 307 307
5.85% notes due 2039    
Debt Instrument [Line Items]    
Stated interest rate 5.85%  
Long-Term Debt $ 271 271
6.40% debentures due 2028    
Debt Instrument [Line Items]    
Stated interest rate 6.40%  
Long-Term Debt $ 251 250
6.30% debentures due 2026    
Debt Instrument [Line Items]    
Stated interest rate 6.30%  
Long-Term Debt $ 135 135
2.75% notes due 2025    
Debt Instrument [Line Items]    
Stated interest rate 2.75%  
Long-Term Debt $ 0 2,498
Other    
Debt Instrument [Line Items]    
Long-Term Debt $ 209 $ 289
v3.25.0.1
Loans Payable, Long-Term Debt and Leases - Balance Sheet Information (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Debt Disclosure [Abstract]    
Other Assets $ 1,370 $ 1,437
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Other Assets Other Assets
Accrued and other current liabilities $ 282 $ 285
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Accrued and other current liabilities Accrued and other current liabilities
Other Noncurrent Liabilities $ 877 $ 928
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Other Noncurrent Liabilities Other Noncurrent Liabilities
Total operating lease liability $ 1,159 $ 1,213
Weighted-average remaining lease term (years) 6 years 7 years
Weighted-average discount rate 3.20% 3.30%
v3.25.0.1
Loans Payable, Long-Term Debt and Leases - Maturity Schedule (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Debt Disclosure [Abstract]    
2025 $ 329  
2026 292  
2027 235  
2028 146  
2029 116  
Thereafter 403  
Total lease payments 1,521  
Less: Imputed interest 362  
Total operating lease liability $ 1,159 $ 1,213
v3.25.0.1
Contingencies and Environmental Liabilities (Details)
$ in Millions
1 Months Ended 2 Months Ended 5 Months Ended 12 Months Ended
Dec. 19, 2022
Jul. 31, 2023
motion
Jun. 30, 2023
May 31, 2023
patent
Oct. 31, 2024
patent
Dec. 31, 2024
USD ($)
case
Plaintiff
Dec. 31, 2023
USD ($)
Loss Contingencies [Line Items]              
Environmental Loss Contingency Statement Of Financial Position Extensible Enumeration Not Disclosed Flag           liabilities  
Accrued liabilities for environmental matters | $           $ 41 $ 42
Term for paying off environmental liabilities           15 years  
Aggregate possible expenditure on environmental matters in excess of amounts accrued | $           $ 46  
Legal Defense Costs              
Loss Contingencies [Line Items]              
Legal defense costs reserve | $           $ 225 $ 210
Commercial and Other Litigation | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, pending claims           2  
Loss contingency, number of plaintiffs | Plaintiff           2  
The Johns Hopkins University              
Loss Contingencies [Line Items]              
Number of patents allegedly infringed | patent       9      
Number of patents allegedly infringed under review | patent         9    
Qui Tam | United States | Settled Litigation              
Loss Contingencies [Line Items]              
Loss contingency, motion for summary judgements granted | motion   2          
Gardasil/Gardasil 9 | United States | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, pending claims           225  
Gardasil/Gardasil 9 | Outside of the United States | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, pending claims           15  
RotaTeq | United States | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, number of plaintiffs           35  
Bridion | Patents              
Loss Contingencies [Line Items]              
Loss contingency, claims settled (in cases)           5  
Bridion | Patents | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, pending claims           2  
Loss contingency, trial period 1 day            
Bridion | Patents | Settled Litigation              
Loss Contingencies [Line Items]              
Patent extension, term     5 years        
Januvia/Janumet              
Loss Contingencies [Line Items]              
Loss contingency, claims settled (in cases)           26  
Dr. Scholl's | United States | Pending Litigation              
Loss Contingencies [Line Items]              
Loss contingency, pending claims           415  
v3.25.0.1
Equity - Narrative (Details) - shares
Dec. 31, 2024
Dec. 31, 2023
Equity [Abstract]    
Common stock, authorized (in shares) 6,500,000,000 6,500,000,000
Preferred stock, authorized (in shares) 20,000,000  
v3.25.0.1
Equity - Shareholders' Equity (Details) - shares
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Movement in Common Stock and Treasury Stock [Roll Forward]      
Balance January 1, common stock (in shares) 3,577,103,522    
Balance January 1, treasury stock (in shares) 1,045,470,249    
Balance December 31, common stock (in shares) 3,577,103,522 3,577,103,522  
Balance December 31, treasury stock (in shares) 1,049,466,187 1,045,470,249  
Common Stock      
Movement in Common Stock and Treasury Stock [Roll Forward]      
Balance January 1, common stock (in shares) 3,577,000,000 3,577,000,000 3,577,000,000
Purchases of treasury stock (in shares) 0 0 0
Issuances (in shares) 0 0 0
Balance December 31, common stock (in shares) 3,577,000,000 3,577,000,000 3,577,000,000
Treasury Stock      
Movement in Common Stock and Treasury Stock [Roll Forward]      
Balance January 1, treasury stock (in shares) 1,045,000,000 1,039,000,000 1,049,000,000
Purchases of treasury stock (in shares) 11,000,000 13,000,000 0
Issuances (in shares) (7,000,000) (7,000,000) (10,000,000)
Balance December 31, treasury stock (in shares) 1,049,000,000 1,045,000,000 1,039,000,000
v3.25.0.1
Share-Based Compensation Plans - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares collectively authorized for future grants under share-based compensation plans (in shares) 75,000,000    
Pretax share-based compensation cost recorded, related to continuing operations $ 761 $ 645 $ 541
Income tax benefits related to share-based compensation $ 117 $ 96 $ 78
Weighted average exercise price of options granted (in dollars per share) $ 129.22 $ 117.89 $ 87.10
Total pre tax unrecognized compensation expense related to nonvested stock options, RSU and PSU awards $ 1,100    
Weighted average period in years of recognition for nonvested stock options, RSU and PSU awards 1 year 10 months 24 days    
Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Quantity of stock options that vest per year 33.33%    
Period over which share-based payment awards vest 3 years    
PSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Period over which share-based payment awards vest 3 years    
RSUs      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Quantity of stock options that vest per year 33.33%    
Period over which share-based payment awards vest 3 years    
Minimum | Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Contractual term of options 7 years    
Maximum | Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Contractual term of options 10 years    
v3.25.0.1
Share-Based Compensation Plans - Assumptions Used to Determine Weighted-Average Fair Value of Options Granted (Details) - $ / shares
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]      
Weighted average fair value of options granted (in dollars per share) $ 25.60 $ 21.69 $ 15.45
Expected dividend yield 3.00% 3.10% 3.10%
Risk-free interest rate 4.70% 3.40% 3.00%
Expected volatility 20.50% 22.40% 22.50%
Expected life (years) 5 years 9 months 18 days 5 years 9 months 18 days 5 years 10 months 24 days
v3.25.0.1
Share-Based Compensation Plans - Summary of Information Relative to Stock Option Plan Activity (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Number of Options      
Number of Options, Outstanding, January 1 (in shares) 13,527    
Number of Options, Granted (in shares) 1,753    
Number of Options, Exercised (in shares) (2,581)    
Number of Options, Forfeited (in shares) (199)    
Number of Options, Outstanding, December 31 (in shares) 12,500 13,527  
Number of Options, Vested and expected to vest (in shares) 12,201    
Number of Options, Exercisable (in shares) 9,084    
Weighted Average Exercise Price      
Weighted Average Exercise Price, Options Outstanding, January 1 (in dollars per share) $ 77.54    
Weighted Average Exercise Price, Granted (in dollars per share) 129.22 $ 117.89 $ 87.10
Weighted Average Exercise Price, Exercised (in dollars per share) 68.90    
Weighted Average Exercise Price, Forfeited (in dollars per share) 111.48    
Weighted Average Exercise Price, Options Outstanding, December 31 (in dollars per share) 86.04 $ 77.54  
Weighted Average Exercise Price, Vested and expected to vest (in dollars per share) 85.10    
Weighted Average Exercise Price, Exercisable (in dollars per share) $ 74.00    
Weighted Average Remaining Contractual Term, Outstanding 5 years 10 months 24 days    
Weighted Average Remaining Contractual Term, Vested and expected to vest 5 years 10 months 24 days    
Weighted Average Remaining Contractual Term, Exercisable 4 years 10 months 24 days    
Aggregate Intrinsic Value, Outstanding $ 249    
Aggregate Intrinsic Value, Vested and expected to vest 249    
Aggregate Intrinsic Value, Exercisable $ 241    
v3.25.0.1
Share-Based Compensation Plans - Additional Information Pertaining to Stock Option Plans (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]      
Total intrinsic value of stock options exercised $ 144 $ 95 $ 225
Fair value of stock options vested 32 30 30
Cash received from the exercise of stock options $ 177 $ 125 $ 384
v3.25.0.1
Share-Based Compensation Plans - Summary of Nonvested RSU and PSU Activity (Details)
shares in Thousands
12 Months Ended
Dec. 31, 2024
$ / shares
shares
RSUs  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]  
Number of Shares, Nonvested January 1 (in shares) | shares 12,542
Number of Shares, Granted (in shares) | shares 6,356
Number of Shares, Vested (in shares) | shares (6,091)
Number of Shares, Forfeited (in shares) | shares (575)
Number of Shares, Nonvested December 31 (in shares) | shares 12,232
Number of Shares, Expected to Vest (in shares) | shares 10,976
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]  
Weighted Average Grant Date Fair Value, Nonvested January 1 (in dollars per share) | $ / shares $ 100.10
Weighted Average Grant Date Fair Value, Granted (in dollars per share) | $ / shares 128.79
Weighted Average Grant Date Fair Value, Vested (in dollars per share) | $ / shares 92.97
Weighted Average Grant Date Fair Value, Forfeited (in dollars per share) | $ / shares 113.18
Weighted Average Grant Date Fair Value, Nonvested December 31 (in dollars per share) | $ / shares 117.94
Weighted Average Grant Date Fair Value, Expected to vest (in dollars per share) | $ / shares $ 117.25
PSUs  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]  
Number of Shares, Nonvested January 1 (in shares) | shares 1,966
Number of Shares, Granted (in shares) | shares 968
Number of Shares, Vested (in shares) | shares (1,109)
Number of Shares, Forfeited (in shares) | shares (59)
Number of Shares, Nonvested December 31 (in shares) | shares 1,766
Number of Shares, Expected to Vest (in shares) | shares 1,669
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]  
Weighted Average Grant Date Fair Value, Nonvested January 1 (in dollars per share) | $ / shares $ 90.80
Weighted Average Grant Date Fair Value, Granted (in dollars per share) | $ / shares 121.91
Weighted Average Grant Date Fair Value, Vested (in dollars per share) | $ / shares 73.50
Weighted Average Grant Date Fair Value, Forfeited (in dollars per share) | $ / shares 121.12
Weighted Average Grant Date Fair Value, Nonvested December 31 (in dollars per share) | $ / shares 117.57
Weighted Average Grant Date Fair Value, Expected to vest (in dollars per share) | $ / shares $ 116.26
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]        
Employer contributions to defined contribution savings plans   $ 215 $ 199 $ 175
Pension Benefits        
Defined Benefit Plan Disclosure [Line Items]        
Accumulated benefit obligation   $ 18,100 $ 19,100  
Percentage of Company's pension investments categorized as level 3 assets   4.00% 4.00%  
Pension Benefits | Level 3        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   $ 700 $ 788  
Other Postretirement Benefits        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   1,040 1,045 $ 947
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year   70    
Other Postretirement Benefits | Level 3        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   $ 0 $ 0  
United States        
Defined Benefit Plan Disclosure [Line Items]        
Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests   12.00%    
Expected rate of return on plan assets   7.75% 7.00% 6.70%
United States | Forecast | Subsequent Event        
Defined Benefit Plan Disclosure [Line Items]        
Expected rate of return on plan assets 7.70%      
United States | U.S. equities | Minimum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   25.00%    
United States | U.S. equities | Maximum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   40.00%    
United States | International equities | Minimum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   15.00%    
United States | International equities | Maximum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   30.00%    
United States | Fixed Income Investments | Minimum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   40.00%    
United States | Fixed Income Investments | Maximum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   50.00%    
United States | Cash And Other Investments | Maximum        
Defined Benefit Plan Disclosure [Line Items]        
Target allocation   8.00%    
United States | Pension Benefits        
Defined Benefit Plan Disclosure [Line Items]        
Accumulated benefit obligation   $ 10,000 $ 10,300  
Fair value of plan assets   9,717 9,804 $ 9,094
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year   270    
United States | Pension Benefits | Level 3        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   2 3 4
International | Pension Benefits        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   9,647 $ 9,562 $ 8,473
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year   $ 180    
Expected rate of return on plan assets   5.20% 5.00% 3.70%
International | Pension Benefits | Level 3        
Defined Benefit Plan Disclosure [Line Items]        
Fair value of plan assets   $ 698 $ 785 $ 761
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Other Postretirement Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Service cost $ 30 $ 32 $ 48
Interest cost 56 63 46
Expected return on plan assets (80) (64) (86)
Amortization of unrecognized prior service (credit) cost (43) (49) (57)
Net loss (gain) amortization (51) (42) (43)
Termination benefits 4 0 0
Curtailments 0 (1) (1)
Settlements 0 0 0
Net periodic benefit cost (credit) (84) (61) (93)
United States | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Service cost 373 326 372
Interest cost 537 526 457
Expected return on plan assets (826) (735) (753)
Amortization of unrecognized prior service (credit) cost 0 (1) (32)
Net loss (gain) amortization 43 0 128
Termination benefits 5 3 2
Curtailments 0 8 12
Settlements 0 28 239
Net periodic benefit cost (credit) 132 155 425
International | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Service cost 243 196 283
Interest cost 294 299 145
Expected return on plan assets (554) (517) (383)
Amortization of unrecognized prior service (credit) cost (13) 2 (14)
Net loss (gain) amortization 5 (3) 96
Termination benefits 1 0 1
Curtailments 0 (1) 0
Settlements (1) (5) 1
Net periodic benefit cost (credit) $ (25) $ (29) $ 129
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Obligation and Funded Status (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Other Postretirement Benefits      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair value of plan assets January 1 $ 1,045 $ 947  
Actual return on plan assets 35 115  
Company contributions 46 74  
Effects of exchange rate changes 0 0  
Benefits paid (89) (95)  
Settlements 0 (2)  
Other 3 6  
Fair value of plan assets December 31 1,040 1,045 $ 947
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
Benefit obligation January 1 1,104 1,157  
Service cost 30 32 48
Interest cost 56 63 46
Actuarial (gains) losses 32 (58)  
Benefits paid (89) (95)  
Effects of exchange rate changes (4) 1  
Plan amendments 0 0  
Curtailments 0 0  
Termination benefits 4 0 0
Settlements 0 (2)  
Other 3 6  
Benefit obligation December 31 1,136 1,104 1,157
Funded status December 31 (96) (59)  
Recognized as:      
Other Assets 51 107  
Accrued and other current liabilities (7) (8)  
Other Noncurrent Liabilities (140) (158)  
United States | Pension Benefits      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair value of plan assets January 1 9,804 9,094  
Actual return on plan assets 266 1,077  
Company contributions 262 307  
Effects of exchange rate changes 0 0  
Benefits paid (615) (497)  
Settlements 0 (177)  
Other 0 0  
Fair value of plan assets December 31 9,717 9,804 9,094
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
Benefit obligation January 1 10,446 9,854  
Service cost 373 326 372
Interest cost 537 526 457
Actuarial (gains) losses (595) 403  
Benefits paid (615) (497)  
Effects of exchange rate changes 0 0  
Plan amendments 0 0  
Curtailments 0 8  
Termination benefits 5 3 2
Settlements 0 (177)  
Other 0 0  
Benefit obligation December 31 10,151 10,446 9,854
Funded status December 31 (434) (642)  
Recognized as:      
Other Assets 26 0  
Accrued and other current liabilities (55) (49)  
Other Noncurrent Liabilities (405) (593)  
International | Pension Benefits      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair value of plan assets January 1 9,562 8,473  
Actual return on plan assets 637 832  
Company contributions 198 249  
Effects of exchange rate changes (522) 283  
Benefits paid (250) (256)  
Settlements (14) (53)  
Other 36 34  
Fair value of plan assets December 31 9,647 9,562 8,473
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
Benefit obligation January 1 9,042 7,755  
Service cost 243 196 283
Interest cost 294 299 145
Actuarial (gains) losses (549) 766  
Benefits paid (250) (256)  
Effects of exchange rate changes (473) 288  
Plan amendments (56) 14  
Curtailments 0 (1)  
Termination benefits 1 0 1
Settlements (14) (53)  
Other 36 34  
Benefit obligation December 31 8,274 9,042 $ 7,755
Funded status December 31 1,373 520  
Recognized as:      
Other Assets 1,785 1,019  
Accrued and other current liabilities (18) (19)  
Other Noncurrent Liabilities $ (394) $ (480)  
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Accumulated and Projected Benefit Obligation in Excess of Plan Assets (Details) - Pension Benefits - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
United States    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Pension plans with a projected benefit obligation in excess of plan assets, projected benefit obligation $ 9,517 $ 10,446
Pension plans with a projected benefit obligation in excess of plan assets, fair value of plan assets 9,057 9,804
Pension plans with an accumulated benefit obligation in excess of plan assets, accumulated benefit obligation 442 9,700
Pension plans with an accumulated benefit obligation in excess of plan assets, fair value of plan assets 0 9,186
International    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Pension plans with a projected benefit obligation in excess of plan assets, projected benefit obligation 1,847 2,961
Pension plans with a projected benefit obligation in excess of plan assets, fair value of plan assets 1,435 2,462
Pension plans with an accumulated benefit obligation in excess of plan assets, accumulated benefit obligation 1,768 1,791
Pension plans with an accumulated benefit obligation in excess of plan assets, fair value of plan assets $ 1,385 $ 1,336
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Fair Values of Pension Plan Assets (Details) - Pension Benefits - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets $ 700 $ 788  
United States      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 9,717 9,804 $ 9,094
United States | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 164 158  
United States | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,555 2,797  
United States | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,265 740  
United States | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 174 113  
United States | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,171 2,071  
United States | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,101 2,307  
United States | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,293 1,485  
United States | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 21 21  
United States | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets (29) 109  
United States | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2 3  
United States | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,355 2,438  
United States | Level 1 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 43 34  
United States | Level 1 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 170 224  
United States | Level 1 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 1 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 1 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,171 2,071  
United States | Level 1 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 1 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 1 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 1 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets (29) 109  
United States | Level 1 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 3,415 3,813  
United States | Level 2 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,101 2,307  
United States | Level 2 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,293 1,485  
United States | Level 2 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 21 21  
United States | Level 2 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 2 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2 3 4
United States | Level 3 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | Level 3 | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0 0
United States | Level 3 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2 3 4
United States | NAV      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 3,945 3,550  
United States | NAV | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 121 124  
United States | NAV | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,385 2,573  
United States | NAV | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,265 740  
United States | NAV | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 174 113  
United States | NAV | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | NAV | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | NAV | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | NAV | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | NAV | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
United States | NAV | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 9,647 9,562 8,473
International | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 123 118  
International | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 4,232 3,870  
International | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 145 110  
International | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 12 10  
International | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 3,385 3,523  
International | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 180 197  
International | Other fixed income obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 19 20  
International | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 287 278  
International | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 368 423  
International | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 141 160  
International | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 54 61  
International | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 701 788  
International | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 4  
International | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,345 1,197  
International | Level 1 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 112 98  
International | Level 1 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 599 507  
International | Level 1 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 54 44  
International | Level 1 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 1 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 262 234  
International | Level 1 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 23 23  
International | Level 1 | Other fixed income obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 8 9  
International | Level 1 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 287 278  
International | Level 1 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 1 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 1 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 1 | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 1 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 4  
International | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 7,090 7,041  
International | Level 2 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 2 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 3,537 3,257  
International | Level 2 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 2 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 2 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,974 3,123  
International | Level 2 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 8 8  
International | Level 2 | Other fixed income obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 7 8  
International | Level 2 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 2 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 368 423  
International | Level 2 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 141 160  
International | Level 2 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 54 61  
International | Level 2 | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1 1  
International | Level 2 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 698 785 761
International | Level 3 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Other fixed income obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | Level 3 | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 698 785 761
International | Level 3 | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0 $ 0
International | NAV      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 514 539  
International | NAV | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 11 20  
International | NAV | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 96 106  
International | NAV | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 91 66  
International | NAV | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 12 10  
International | NAV | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 149 166  
International | NAV | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 149 166  
International | NAV | Other fixed income obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 4 3  
International | NAV | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | NAV | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | NAV | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | NAV | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
International | NAV | Insurance contracts      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2 2  
International | NAV | Other      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets $ 0 $ 0  
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Summary of Changes in Fair Value of Company's Level 3 Pension Plan Assets (Details) - Pension Benefits - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Level 3    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 $ 788  
Actual return on plan assets:    
Fair value of plan assets December 31 700 $ 788
United States    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 9,804 9,094
Actual return on plan assets:    
Fair value of plan assets December 31 9,717 9,804
United States | Other    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 3  
Actual return on plan assets:    
Fair value of plan assets December 31 2 3
United States | Level 3    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 3 4
Actual return on plan assets:    
Relating to assets still held at December 31 (2) (2)
Relating to assets sold during the year 2 2
Purchases and sales, net (1) (1)
Fair value of plan assets December 31 2 3
United States | Level 3 | Insurance Contracts    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 0 0
Actual return on plan assets:    
Relating to assets still held at December 31 0 0
Relating to assets sold during the year 0 0
Purchases and sales, net 0 0
Fair value of plan assets December 31 0 0
United States | Level 3 | Other    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 3 4
Actual return on plan assets:    
Relating to assets still held at December 31 (2) (2)
Relating to assets sold during the year 2 2
Purchases and sales, net (1) (1)
Fair value of plan assets December 31 2 3
International    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 9,562 8,473
Actual return on plan assets:    
Fair value of plan assets December 31 9,647 9,562
International | Insurance Contracts    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 788  
Actual return on plan assets:    
Fair value of plan assets December 31 701 788
International | Other    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 4  
Actual return on plan assets:    
Fair value of plan assets December 31 0 4
International | Level 3    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 785 761
Actual return on plan assets:    
Relating to assets still held at December 31 (26) 77
Purchases and sales, net (61) (53)
Fair value of plan assets December 31 698 785
International | Level 3 | Insurance Contracts    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 785 761
Actual return on plan assets:    
Relating to assets still held at December 31 (26) 77
Purchases and sales, net (61) (53)
Fair value of plan assets December 31 698 785
International | Level 3 | Other    
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]    
Fair value of plan assets January 1 0 0
Actual return on plan assets:    
Relating to assets still held at December 31 0 0
Purchases and sales, net 0 0
Fair value of plan assets December 31 $ 0 $ 0
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Fair Values of Other Postretirement Benefit Plan Assets (Details) - Other Postretirement Benefits - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value $ 1,040 $ 1,045 $ 947
Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 5 13  
Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 49 301  
Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 24 80  
Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 3 12  
Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 41 223  
Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 598 157  
Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 266 245  
Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 54 2  
Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 12  
Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 44 259  
Level 1 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 3 24  
Level 1 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 41 223  
Level 1 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 1 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 12  
Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 918 404  
Level 2 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 2 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 2 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 2 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 2 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 2 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 598 157  
Level 2 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 266 245  
Level 2 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 54 2  
Level 2 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
Level 3 | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
NAV      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 78 382  
NAV | Cash and cash equivalents      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 5 13  
NAV | Developed markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 46 277  
NAV | Emerging markets equities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 24 80  
NAV | Real estate      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 3 12  
NAV | Developed markets      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0  
NAV | Corporate obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0  
NAV | Government and agency obligations      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0  
NAV | Mortgage and asset-backed securities      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value 0 0  
NAV | Derivatives      
Defined Benefit Plan Disclosure [Line Items]      
Plan assets at fair value $ 0 $ 0  
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Summary of Expected Benefit Payments (Details)
$ in Millions
Dec. 31, 2024
USD ($)
Other Postretirement Benefits  
Defined Benefit Plan Disclosure [Line Items]  
2025 $ 86
2026 87
2027 89
2028 91
2029 96
2030 — 2034 515
United States | Pension Benefits  
Defined Benefit Plan Disclosure [Line Items]  
2025 771
2026 775
2027 789
2028 799
2029 822
2030 — 2034 4,386
International | Pension Benefits  
Defined Benefit Plan Disclosure [Line Items]  
2025 291
2026 275
2027 286
2028 300
2029 314
2030 — 2034 $ 1,792
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Components of Other Comprehensive Income (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Other Postretirement Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Net gain (loss) arising during the period $ (78) $ 110 $ 0
Prior service credit (cost) arising during the period 0 0 0
Total (78) 110 0
Net loss (gain) amortization included in benefit cost (51) (42) (43)
Prior service (credit) cost amortization included in benefit cost (43) (49) (57)
Settlements and curtailments 0 (1) (1)
Total (94) (92) (101)
United States | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Net gain (loss) arising during the period 35 (69) (42)
Prior service credit (cost) arising during the period 0 0 0
Total 35 (69) (42)
Net loss (gain) amortization included in benefit cost 43 0 128
Prior service (credit) cost amortization included in benefit cost 0 (1) (32)
Settlements and curtailments 0 36 251
Total 43 35 347
International | Pension Benefits      
Defined Benefit Plan Disclosure [Line Items]      
Net gain (loss) arising during the period 634 (438) 116
Prior service credit (cost) arising during the period 56 (16) (4)
Total 690 (454) 112
Net loss (gain) amortization included in benefit cost 5 (3) 96
Prior service (credit) cost amortization included in benefit cost (13) 2 (14)
Settlements and curtailments (1) (6) 1
Total $ (9) $ (7) $ 83
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Summary of Weighted Average Assumptions Used in Determining Pension Plan and U.S. Pension and Other Postretirement Benefit Plan Information (Details)
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
United States      
Net periodic benefit cost      
Discount rate 5.30% 5.50% 3.00%
Expected rate of return on plan assets 7.75% 7.00% 6.70%
Salary growth rate 4.60% 4.60% 4.60%
Interest crediting rate 5.30% 5.30% 5.00%
Benefit obligation      
Discount rate 5.70% 5.30% 5.50%
Salary growth rate 4.80% 4.60% 4.60%
Interest crediting rate 5.40% 5.30% 5.30%
International | Pension Benefits      
Net periodic benefit cost      
Discount rate 3.40% 3.90% 1.50%
Expected rate of return on plan assets 5.20% 5.00% 3.70%
Salary growth rate 3.20% 3.20% 2.90%
Interest crediting rate 3.40% 3.30% 3.00%
Benefit obligation      
Discount rate 3.70% 3.40% 3.90%
Salary growth rate 3.10% 3.20% 3.20%
Interest crediting rate 3.50% 3.40% 3.30%
v3.25.0.1
Pension and Other Postretirement Benefit Plans - Summary of Health Care Cost Trend Rate Assumptions for Other Postretirement Benefit Plans (Details) - Other Postretirement Benefits
Dec. 31, 2024
Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]    
Health care cost trend rate assumed for next year 7.90% 7.80%
Rate to which the cost trend rate is assumed to decline 4.50% 4.50%
v3.25.0.1
Other (Income) Expense, Net - Schedule of Other (Income) Expense, Net (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Other Income and Expenses [Abstract]      
Interest income $ (415) $ (365) $ (157)
Interest expense 1,271 1,146 962
Exchange losses 227 370 237
(Income) loss from investments in equity securities, net (14) (340) 1,419
Net periodic defined benefit plan (credit) cost other than service cost (633) (498) (279)
Other, net (460) 153 (681)
Other (income) expense, net $ (24) $ 466 $ 1,501
v3.25.0.1
Other (Income) Expense, Net - Narrative (Details) - USD ($)
$ in Millions
1 Months Ended 12 Months Ended
Aug. 31, 2024
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Component of Other Income / Expense of Nonoperating [Line Items]        
Interest paid   $ 1,300.0 $ 1,100.0 $ 937.0
Zetia antitrust litigation        
Component of Other Income / Expense of Nonoperating [Line Items]        
Loss related to settlement litigation     $ 572.5  
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement        
Component of Other Income / Expense of Nonoperating [Line Items]        
Upfront cash payment $ 170.0      
v3.25.0.1
Taxes on Income - Reconciliation Between Effective Tax Rate and US Statutory Rate (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Amount      
U.S. statutory rate applied to income before taxes $ 4,186 $ 397 $ 3,453
Differential arising from:      
Foreign earnings (1,301) (941) (1,821)
Tax settlements and statute lapses (557) 0 (10)
R&D tax credit (202) (214) (117)
Inventory donations (71) (65) (52)
State taxes (39) (117) (110)
Charges for certain research and development asset acquisitions 554 253 0
Valuation allowances 54 70 108
Restructuring 52 41 11
GILTI and the foreign-derived intangible income deduction 29 (80) 462
Acquisition-related costs, including amortization 18 42 (3)
Acquisition of Prometheus 0 2,139 0
Other 80 (13) (3)
Taxes on income $ 2,803 $ 1,512 $ 1,918
Tax Rate      
U.S. statutory rate applied to income before taxes 21.00% 21.00% 21.00%
Differential arising from:      
Foreign earnings (6.50%) (49.80%) (11.10%)
Tax settlements and statute lapses (2.80%) 0.00% (0.10%)
R&D tax credit (1.00%) (11.30%) (0.70%)
Inventory donations (0.40%) (3.50%) (0.30%)
State taxes (0.20%) (6.20%) (0.70%)
Charges for certain research and development asset acquisitions 2.80% 13.40% 0.00%
Valuation allowances 0.30% 3.70% 0.70%
Restructuring 0.30% 2.20% 0.10%
GILTI and the foreign-derived intangible income deduction 0.10% (4.30%) 2.80%
Acquisition-related costs, including amortization 0.10% 2.20% 0.00%
Acquisition of Prometheus 0.00% 113.30% 0.00%
Other 0.40% (0.70%) 0.00%
Total, Tax Rate 14.10% 80.00% 11.70%
v3.25.0.1
Taxes on Income - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Income Tax Contingency [Line Items]        
Transition tax for accumulated foreign earnings, liability $ 518      
Transition tax liability, current 1,200      
Transition tax asset, credit, noncurrent 702      
Deferred tax assets on NOL carryforwards relating to foreign jurisdictions 324      
Deferred tax assets relating to various U.S. tax credit carryforwards and NOL carryforwards 586      
Tax benefits relating to stock option exercises 26 $ 12 $ 45  
Unrecognized tax benefits 2,261 2,384 1,835 $ 1,529
Favorable net impact to income tax provision if unrecognized tax benefits were recognized 2,200      
Reasonably possible amount that liability for unrecognized tax benefits could decline up to in next 12 months (up to) 22      
Interest and penalties associated with uncertain tax positions, expense (benefit) 51 131 $ 54  
Liabilities for accrued interest and penalties 437 $ 388    
Tax Year 2019 and 2020        
Income Tax Contingency [Line Items]        
Reduction in reserves resulting from lapse of statute of limitations 519      
Foreign Jurisdiction        
Income Tax Contingency [Line Items]        
Valuation allowance on foreign NOL carryforwards 264      
Federal        
Income Tax Contingency [Line Items]        
Valuation allowance on foreign NOL carryforwards $ 446      
v3.25.0.1
Taxes on Income - Income Before Taxes (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Income Tax Disclosure [Abstract]      
Domestic $ (1,849) $ (15,622) $ 1,011
Foreign 21,785 17,511 15,433
Income Before Taxes $ 19,936 $ 1,889 $ 16,444
v3.25.0.1
Taxes on Income - Taxes on Income (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Current provision      
Federal $ 944 $ 928 $ 2,265
Foreign 3,123 2,435 1,164
State (15) 48 57
Total current provision 4,052 3,411 3,486
Deferred provision      
Federal (1,475) (1,559) (1,510)
Foreign 212 (233) 71
State 14 (107) (129)
Total deferred provision (1,249) (1,899) (1,568)
Taxes on income $ 2,803 $ 1,512 $ 1,918
v3.25.0.1
Taxes on Income - Deferred Income Taxes (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Income Tax [Line Items]    
Product intangibles and licenses, Assets $ 71  
Product intangibles and licenses, Liabilities 978 $ 1,308
R&D capitalization, Assets 3,062 2,099
Inventory related, Assets 84 86
Inventory related, Liabilities 413 370
Accelerated depreciation, Liabilities 645 626
Undistributed foreign earnings, Assets 275 76
Undistributed foreign earnings, Liabilities 371 118
Equity method investments, Liabilities 90 73
Pensions and other postretirement benefits, Assets 224 323
Pensions and other postretirement benefits, Liabilities 400 249
Compensation related, Assets 400 357
Unrecognized tax benefits, Assets 152 147
Net operating losses and other tax credit carryforwards, Assets 910 868
Other, Assets 802 755
Other, Liabilities 159 214
Subtotal, Assets 5,980 4,711
Subtotal, Liabilities 3,056 2,958
Valuation allowance, Assets (710) (656)
Total deferred taxes 5,270 4,055
Deferred income taxes, Assets 2,214 1,097
Deferred Income Taxes 1,387 871
Other Assets    
Income Tax [Line Items]    
Total deferred taxes $ 3,601 $ 1,968
v3.25.0.1
Taxes on Income - Income Tax Authority (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Income Tax Contingency [Line Items]      
Income taxes paid $ 3,928 $ 4,338 $ 3,239
Federal      
Income Tax Contingency [Line Items]      
Income taxes paid 974 2,258 1,891
Foreign Jurisdiction      
Income Tax Contingency [Line Items]      
Income taxes paid $ 2,954 $ 2,080 $ 1,348
v3.25.0.1
Taxes on Income - Unrecognized Tax Benefits (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits [Roll Forward]      
Balance January 1 $ 2,384 $ 1,835 $ 1,529
Additions related to current year positions 421 553 344
Additions related to prior year positions 35 91 48
Reductions for tax positions of prior years (33) (20) (40)
Settlements (18) (23) (6)
Lapse of statute of limitations (528) (52) (40)
Balance December 31 2,261 $ 2,384 $ 1,835
Tax Year 2019 and 2020      
Reconciliation of Unrecognized Tax Benefits [Roll Forward]      
Lapse of statute of limitations $ (451)    
v3.25.0.1
Earnings Per Share - Calculations of Earnings Per Share (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Earnings Per Share [Abstract]      
Net income attributable to Merck & Co., Inc., basic $ 17,117 $ 365 $ 14,519
Net income attributable to Merck & Co., Inc., diluted $ 17,117 $ 365 $ 14,519
Average common shares outstanding (in shares) 2,532 2,537 2,532
Common shares issuable (in shares) 9 10 10
Average common shares outstanding assuming dilution (in shares) 2,541 2,547 2,542
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share) $ 6.76 $ 0.14 $ 5.73
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders (in dollars per share) $ 6.74 $ 0.14 $ 5.71
v3.25.0.1
Earnings Per Share - Narrative (Details) - shares
shares in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Earnings Per Share [Abstract]      
Antidilutive shares (in shares) 6 5 2
v3.25.0.1
Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Beginning balance $ 37,635 $ 46,058 $ 38,257
Other comprehensive income (loss), net of taxes 216 (393) (339)
Ending balance 46,372 37,635 46,058
Derivatives      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Beginning balance (24) 73 144
Other comprehensive income (loss) before reclassification adjustments, pretax 508 114 684
Tax (109) (24) (143)
Other comprehensive income (loss) before reclassification adjustments, net of taxes 399 90 541
Reclassification adjustments, pretax (168) (237) (775)
Tax 35 50 163
Reclassification adjustments, net of taxes (133) (187) (612)
Other comprehensive income (loss), net of taxes 266 (97) (71)
Ending balance 242 (24) 73
Employee Benefit Plans      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Beginning balance (2,793) (2,408) (2,743)
Other comprehensive income (loss) before reclassification adjustments, pretax 647 (413) 70
Tax (138) 86 12
Other comprehensive income (loss) before reclassification adjustments, net of taxes 509 (327) 82
Reclassification adjustments, pretax (60) (64) 329
Tax 17 6 (76)
Reclassification adjustments, net of taxes (43) (58) 253
Other comprehensive income (loss), net of taxes 466 (385) 335
Ending balance (2,327) (2,793) (2,408)
Pension Plan Net Loss      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Pension and other postretirement benefit plans, net loss (gain) and prior service (credit) included in AOCI 3,000 3,500  
Other Postretirement Benefit Plan Net Gain      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Pension and other postretirement benefit plans, net loss (gain) and prior service (credit) included in AOCI (400) (500)  
Pension Plan Prior Service Credit      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Pension and other postretirement benefit plans, net loss (gain) and prior service (credit) included in AOCI (174) (141)  
Other Postretirement Benefit Plan Prior Service Credit      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Pension and other postretirement benefit plans, net loss (gain) and prior service (credit) included in AOCI (61) (95)  
Foreign Currency Translation Adjustment      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Beginning balance (2,344) (2,433) (1,830)
Other comprehensive income (loss) before reclassification adjustments, pretax (559) 17 (584)
Tax 23 63 (19)
Other comprehensive income (loss) before reclassification adjustments, net of taxes (536) 80 (603)
Reclassification adjustments, pretax 20 9 0
Tax 0 0 0
Reclassification adjustments, net of taxes 20 9 0
Other comprehensive income (loss), net of taxes (516) 89 (603)
Ending balance (2,860) (2,344) (2,433)
Accumulated Other Comprehensive Loss      
Accumulated Other Comprehensive Income (Loss) [Roll Forward]      
Beginning balance (5,161) (4,768) (4,429)
Other comprehensive income (loss) before reclassification adjustments, pretax 596 (282) 170
Tax (224) 125 (150)
Other comprehensive income (loss) before reclassification adjustments, net of taxes 372 (157) 20
Reclassification adjustments, pretax (208) (292) (446)
Tax 52 56 87
Reclassification adjustments, net of taxes (156) (236) (359)
Other comprehensive income (loss), net of taxes 216 (393) (339)
Ending balance $ (4,945) $ (5,161) $ (4,768)
v3.25.0.1
Segment Reporting - Narrative (Details)
12 Months Ended
Dec. 31, 2024
segment
Segment Reporting [Abstract]  
Number of operating segments 2
v3.25.0.1
Segment Reporting - Sales of Company's Products (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Segment Reporting Information [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
Increase (decrease) in revenue hedging activities 195 244 810
Revenue related to the sale of the marketing rights 106 118 165
Operating Segments      
Segment Reporting Information [Line Items]      
Sales 63,277 59,208 57,555
Operating Segments | Pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 57,400 53,583 52,005
Operating Segments | Pharmaceutical | Keytruda      
Segment Reporting Information [Line Items]      
Sales 29,482 25,011 20,937
Operating Segments | Pharmaceutical | Alliance revenue - Lynparza      
Segment Reporting Information [Line Items]      
Sales 1,311 1,199 1,116
Operating Segments | Pharmaceutical | Alliance revenue - Lenvima      
Segment Reporting Information [Line Items]      
Sales 1,010 960 876
Operating Segments | Pharmaceutical | Welireg      
Segment Reporting Information [Line Items]      
Sales 509 218 123
Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl      
Segment Reporting Information [Line Items]      
Sales 371 212 166
Operating Segments | Pharmaceutical | Gardasil/Gardasil 9      
Segment Reporting Information [Line Items]      
Sales 8,583 8,886 6,897
Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax      
Segment Reporting Information [Line Items]      
Sales 2,485 2,368 2,241
Operating Segments | Pharmaceutical | Vaxneuvance      
Segment Reporting Information [Line Items]      
Sales 808 665 170
Operating Segments | Pharmaceutical | RotaTeq      
Segment Reporting Information [Line Items]      
Sales 711 769 783
Operating Segments | Pharmaceutical | Pneumovax 23      
Segment Reporting Information [Line Items]      
Sales 263 412 602
Operating Segments | Pharmaceutical | Bridion      
Segment Reporting Information [Line Items]      
Sales 1,764 1,842 1,685
Operating Segments | Pharmaceutical | Prevymis      
Segment Reporting Information [Line Items]      
Sales 785 605 428
Operating Segments | Pharmaceutical | Dificid      
Segment Reporting Information [Line Items]      
Sales 340 302 263
Operating Segments | Pharmaceutical | Zerbaxa      
Segment Reporting Information [Line Items]      
Sales 252 218 169
Operating Segments | Pharmaceutical | Noxafil      
Segment Reporting Information [Line Items]      
Sales 177 213 238
Operating Segments | Pharmaceutical | Winrevair      
Segment Reporting Information [Line Items]      
Sales 419 0 0
Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo      
Segment Reporting Information [Line Items]      
Sales 415 367 341
Operating Segments | Pharmaceutical | Adempas      
Segment Reporting Information [Line Items]      
Sales 287 255 238
Operating Segments | Pharmaceutical | Lagevrio      
Segment Reporting Information [Line Items]      
Sales 964 1,428 5,684
Operating Segments | Pharmaceutical | Isentress/Isentress HD      
Segment Reporting Information [Line Items]      
Sales 394 483 633
Operating Segments | Pharmaceutical | Delstrigo      
Segment Reporting Information [Line Items]      
Sales 249 201 151
Operating Segments | Pharmaceutical | Pifeltro      
Segment Reporting Information [Line Items]      
Sales 163 142 118
Operating Segments | Pharmaceutical | Belsomra      
Segment Reporting Information [Line Items]      
Sales 222 231 258
Operating Segments | Pharmaceutical | Simponi      
Segment Reporting Information [Line Items]      
Sales 543 710 706
Operating Segments | Pharmaceutical | Remicade      
Segment Reporting Information [Line Items]      
Sales 114 187 207
Operating Segments | Pharmaceutical | Januvia      
Segment Reporting Information [Line Items]      
Sales 1,334 2,189 2,813
Operating Segments | Pharmaceutical | Janumet      
Segment Reporting Information [Line Items]      
Sales 935 1,177 1,700
Operating Segments | Pharmaceutical | Other pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 2,510 2,333 2,462
Operating Segments | Animal Health      
Segment Reporting Information [Line Items]      
Sales 5,877 5,625 5,550
Operating Segments | Animal Health | Livestock      
Segment Reporting Information [Line Items]      
Sales 3,462 3,337 3,300
Operating Segments | Animal Health | Companion Animal      
Segment Reporting Information [Line Items]      
Sales 2,415 2,288 2,250
Other      
Segment Reporting Information [Line Items]      
Sales 891 907 1,728
United States      
Segment Reporting Information [Line Items]      
Sales 32,277 28,480 27,206
United States | Operating Segments      
Segment Reporting Information [Line Items]      
Sales 32,151 28,343 26,811
United States | Operating Segments | Pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 30,290 26,539 24,989
United States | Operating Segments | Pharmaceutical | Keytruda      
Segment Reporting Information [Line Items]      
Sales 17,872 15,114 12,686
United States | Operating Segments | Pharmaceutical | Alliance revenue - Lynparza      
Segment Reporting Information [Line Items]      
Sales 626 607 584
United States | Operating Segments | Pharmaceutical | Alliance revenue - Lenvima      
Segment Reporting Information [Line Items]      
Sales 705 657 579
United States | Operating Segments | Pharmaceutical | Welireg      
Segment Reporting Information [Line Items]      
Sales 466 209 123
United States | Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl      
Segment Reporting Information [Line Items]      
Sales 303 168 123
United States | Operating Segments | Pharmaceutical | Gardasil/Gardasil 9      
Segment Reporting Information [Line Items]      
Sales 2,425 2,083 2,065
United States | Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax      
Segment Reporting Information [Line Items]      
Sales 1,919 1,837 1,724
United States | Operating Segments | Pharmaceutical | Vaxneuvance      
Segment Reporting Information [Line Items]      
Sales 461 561 163
United States | Operating Segments | Pharmaceutical | RotaTeq      
Segment Reporting Information [Line Items]      
Sales 472 493 508
United States | Operating Segments | Pharmaceutical | Pneumovax 23      
Segment Reporting Information [Line Items]      
Sales 56 127 346
United States | Operating Segments | Pharmaceutical | Bridion      
Segment Reporting Information [Line Items]      
Sales 1,401 1,156 922
United States | Operating Segments | Pharmaceutical | Prevymis      
Segment Reporting Information [Line Items]      
Sales 371 264 188
United States | Operating Segments | Pharmaceutical | Dificid      
Segment Reporting Information [Line Items]      
Sales 303 274 241
United States | Operating Segments | Pharmaceutical | Zerbaxa      
Segment Reporting Information [Line Items]      
Sales 146 119 89
United States | Operating Segments | Pharmaceutical | Noxafil      
Segment Reporting Information [Line Items]      
Sales 7 32 51
United States | Operating Segments | Pharmaceutical | Winrevair      
Segment Reporting Information [Line Items]      
Sales 408 0 0
United States | Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo      
Segment Reporting Information [Line Items]      
Sales 388 350 329
United States | Operating Segments | Pharmaceutical | Adempas      
Segment Reporting Information [Line Items]      
Sales 0 0 0
United States | Operating Segments | Pharmaceutical | Lagevrio      
Segment Reporting Information [Line Items]      
Sales 176 10 1,523
United States | Operating Segments | Pharmaceutical | Isentress/Isentress HD      
Segment Reporting Information [Line Items]      
Sales 185 215 274
United States | Operating Segments | Pharmaceutical | Delstrigo      
Segment Reporting Information [Line Items]      
Sales 56 49 39
United States | Operating Segments | Pharmaceutical | Pifeltro      
Segment Reporting Information [Line Items]      
Sales 113 101 87
United States | Operating Segments | Pharmaceutical | Belsomra      
Segment Reporting Information [Line Items]      
Sales 72 81 79
United States | Operating Segments | Pharmaceutical | Simponi      
Segment Reporting Information [Line Items]      
Sales 0 0 0
United States | Operating Segments | Pharmaceutical | Remicade      
Segment Reporting Information [Line Items]      
Sales 0 0 0
United States | Operating Segments | Pharmaceutical | Januvia      
Segment Reporting Information [Line Items]      
Sales 469 1,151 1,248
United States | Operating Segments | Pharmaceutical | Janumet      
Segment Reporting Information [Line Items]      
Sales 161 223 355
United States | Operating Segments | Pharmaceutical | Other pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 729 658 663
United States | Operating Segments | Animal Health      
Segment Reporting Information [Line Items]      
Sales 1,861 1,804 1,822
United States | Operating Segments | Animal Health | Livestock      
Segment Reporting Information [Line Items]      
Sales 732 700 710
United States | Operating Segments | Animal Health | Companion Animal      
Segment Reporting Information [Line Items]      
Sales 1,129 1,104 1,112
United States | Other      
Segment Reporting Information [Line Items]      
Sales 126 137 395
Int’l      
Segment Reporting Information [Line Items]      
Sales 31,891 31,635 32,077
Int’l | Operating Segments      
Segment Reporting Information [Line Items]      
Sales 31,126 30,865 30,744
Int’l | Operating Segments | Pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 27,110 27,044 27,016
Int’l | Operating Segments | Pharmaceutical | Keytruda      
Segment Reporting Information [Line Items]      
Sales 11,610 9,897 8,251
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Lynparza      
Segment Reporting Information [Line Items]      
Sales 685 592 532
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Lenvima      
Segment Reporting Information [Line Items]      
Sales 305 303 297
Int’l | Operating Segments | Pharmaceutical | Welireg      
Segment Reporting Information [Line Items]      
Sales 43 10 0
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl      
Segment Reporting Information [Line Items]      
Sales 68 43 43
Int’l | Operating Segments | Pharmaceutical | Gardasil/Gardasil 9      
Segment Reporting Information [Line Items]      
Sales 6,158 6,803 4,832
Int’l | Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax      
Segment Reporting Information [Line Items]      
Sales 566 531 518
Int’l | Operating Segments | Pharmaceutical | Vaxneuvance      
Segment Reporting Information [Line Items]      
Sales 347 103 7
Int’l | Operating Segments | Pharmaceutical | RotaTeq      
Segment Reporting Information [Line Items]      
Sales 239 276 275
Int’l | Operating Segments | Pharmaceutical | Pneumovax 23      
Segment Reporting Information [Line Items]      
Sales 207 285 256
Int’l | Operating Segments | Pharmaceutical | Bridion      
Segment Reporting Information [Line Items]      
Sales 363 686 762
Int’l | Operating Segments | Pharmaceutical | Prevymis      
Segment Reporting Information [Line Items]      
Sales 414 341 240
Int’l | Operating Segments | Pharmaceutical | Dificid      
Segment Reporting Information [Line Items]      
Sales 37 28 22
Int’l | Operating Segments | Pharmaceutical | Zerbaxa      
Segment Reporting Information [Line Items]      
Sales 106 100 79
Int’l | Operating Segments | Pharmaceutical | Noxafil      
Segment Reporting Information [Line Items]      
Sales 170 181 187
Int’l | Operating Segments | Pharmaceutical | Winrevair      
Segment Reporting Information [Line Items]      
Sales 11 0 0
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo      
Segment Reporting Information [Line Items]      
Sales 27 16 12
Int’l | Operating Segments | Pharmaceutical | Adempas      
Segment Reporting Information [Line Items]      
Sales 287 255 238
Int’l | Operating Segments | Pharmaceutical | Lagevrio      
Segment Reporting Information [Line Items]      
Sales 787 1,418 4,161
Int’l | Operating Segments | Pharmaceutical | Isentress/Isentress HD      
Segment Reporting Information [Line Items]      
Sales 209 268 359
Int’l | Operating Segments | Pharmaceutical | Delstrigo      
Segment Reporting Information [Line Items]      
Sales 193 152 111
Int’l | Operating Segments | Pharmaceutical | Pifeltro      
Segment Reporting Information [Line Items]      
Sales 50 41 30
Int’l | Operating Segments | Pharmaceutical | Belsomra      
Segment Reporting Information [Line Items]      
Sales 150 150 179
Int’l | Operating Segments | Pharmaceutical | Simponi      
Segment Reporting Information [Line Items]      
Sales 543 710 706
Int’l | Operating Segments | Pharmaceutical | Remicade      
Segment Reporting Information [Line Items]      
Sales 114 187 207
Int’l | Operating Segments | Pharmaceutical | Januvia      
Segment Reporting Information [Line Items]      
Sales 865 1,039 1,565
Int’l | Operating Segments | Pharmaceutical | Janumet      
Segment Reporting Information [Line Items]      
Sales 774 954 1,344
Int’l | Operating Segments | Pharmaceutical | Other pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 1,782 1,675 1,803
Int’l | Operating Segments | Animal Health      
Segment Reporting Information [Line Items]      
Sales 4,016 3,821 3,728
Int’l | Operating Segments | Animal Health | Livestock      
Segment Reporting Information [Line Items]      
Sales 2,729 2,637 2,590
Int’l | Operating Segments | Animal Health | Companion Animal      
Segment Reporting Information [Line Items]      
Sales 1,287 1,184 1,138
Int’l | Other      
Segment Reporting Information [Line Items]      
Sales $ 765 $ 770 $ 1,333
v3.25.0.1
Segment Reporting - Consolidated Revenues by Geographic Area (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
United States      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 32,277 28,480 27,206
Europe, Middle East and Africa      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 14,041 13,254 14,493
China      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 5,494 6,802 5,191
Latin America      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 3,459 3,086 2,582
Japan      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 3,280 3,164 3,629
Asia Pacific (other than China and Japan)      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales 3,058 3,225 3,614
Other      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Sales $ 2,559 $ 2,104 $ 2,568
v3.25.0.1
Segment Reporting - Reconciliation of Segment Profits to Income Before Taxes (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Segment Reporting Information [Line Items]      
Sales $ 64,168 $ 60,115 $ 59,283
Cost of sales 15,193 16,126 17,411
Selling, general and administrative 10,816 10,504 10,042
Research and development 17,938 30,531 13,548
Other segment items (24) 466 1,501
Income Before Taxes 19,936 1,889 16,444
Interest income 415 365 157
Interest expense (1,271) (1,146) (962)
Amortization (2,395) (2,044) (2,085)
Depreciation (2,104) (1,828) (1,824)
Research and development (17,938) (30,531) (13,548)
Restructuring costs (309) (599) (337)
Total segment profits      
Segment Reporting Information [Line Items]      
Sales 63,277 59,208 57,555
Income Before Taxes 46,471 40,617 38,815
Depreciation (261) (203) (182)
Total segment profits | Pharmaceutical      
Segment Reporting Information [Line Items]      
Sales 57,400 53,583 52,005
Cost of sales 6,828 8,849 9,678
Selling, general and administrative 6,128 5,903 5,474
Research and development 0 0 0
Other segment items (89) (49) 1
Income Before Taxes 44,533 38,880 36,852
Depreciation (5) (5) (5)
Research and development 0 0 0
Total segment profits | Animal Health      
Segment Reporting Information [Line Items]      
Sales 5,877 5,625 5,550
Cost of sales 2,469 2,498 2,259
Selling, general and administrative 1,084 1,038 999
Research and development 385 353 329
Other segment items 1 (1) 0
Income Before Taxes 1,938 1,737 1,963
Depreciation (256) (198) (177)
Research and development (385) (353) (329)
Other profits      
Segment Reporting Information [Line Items]      
Sales 891 907 1,728
Research and development 17,350 30,008 13,011
Income Before Taxes 492 474 1,160
Interest income 415 365 157
Interest expense (1,271) (1,146) (962)
Amortization (2,395) (2,044) (2,085)
Depreciation (1,843) (1,625) (1,642)
Research and development (17,350) (30,008) (13,011)
Restructuring costs (309) (599) (337)
Charge for Zetia antitrust litigation settlements 0 (573) 0
Other unallocated, net $ (4,274) $ (3,572) $ (5,651)
v3.25.0.1
Segment Reporting - Equity Income from Affiliates and Depreciation Included in Segment Profits (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Segment Reporting Information [Line Items]      
Depreciation $ 2,104 $ 1,828 $ 1,824
Operating Segments      
Segment Reporting Information [Line Items]      
Equity income from affiliates 144 111 39
Depreciation 261 203 182
Operating Segments | Pharmaceutical      
Segment Reporting Information [Line Items]      
Equity income from affiliates 144 111 39
Depreciation 5 5 5
Operating Segments | Animal Health      
Segment Reporting Information [Line Items]      
Equity income from affiliates 0 0 0
Depreciation $ 256 $ 198 $ 177
v3.25.0.1
Segment Reporting - Property, Plant and Equipment, Net by Geographic Area (Details) - USD ($)
$ in Millions
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net $ 23,779 $ 23,051 $ 21,422
United States      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 14,724 13,915 12,891
Europe, Middle East and Africa      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 7,548 7,562 6,993
Asia Pacific (other than China and Japan)      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 982 1,022 966
China      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 202 193 207
Japan      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 143 133 135
Latin America      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net 133 222 225
Other      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Property, plant and equipment, net $ 47 $ 4 $ 5