ARCHER AVIATION INC., 10-Q filed on 5/12/2025
Quarterly Report
v3.25.1
Cover Page - shares
 3 Months Ended
Mar. 31, 2025
May 06, 2025
Entity Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 001-39668  
Entity Registrant Name Archer Aviation Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 85-2730902  
Entity Address, Address Line One 190 West Tasman Drive  
Entity Address, City or Town San Jose  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 95134  
City Area Code 650  
Local Phone Number 272-3233  
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  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   549,011,059
Entity Central Index Key 0001824502  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Class A    
Entity Information [Line Items]    
Title of 12(b) Security Class A common stock, par value $0.0001 per share  
Trading Symbol ACHR  
Security Exchange Name NYSE  
Warrants    
Entity Information [Line Items]    
Title of 12(b) Security Warrants, each whole warrant exercisable for one share of Class A common stock at an exercise price of $11.50 per share  
Trading Symbol ACHR WS  
Security Exchange Name NYSE  
v3.25.1
Consolidated Condensed Balance Sheets - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Current assets    
Cash and cash equivalents $ 1,030.4 $ 834.5
Restricted cash 6.5 6.8
Prepaid expenses 22.3 12.5
Other current assets 5.8 4.6
Total current assets 1,065.0 858.4
Property and equipment, net 132.1 126.8
Intangible assets, net 0.3 0.3
Right-of-use assets 7.6 8.1
Other long-term assets 9.6 7.6
Total assets 1,214.6 1,001.2
Current liabilities    
Accounts payable 14.8 14.6
Current portion of lease liabilities 4.0 3.7
Accrued expenses and other current liabilities 48.6 52.8
Total current liabilities 67.4 71.1
Notes payable 64.1 64.0
Lease liabilities, net of current portion 10.2 11.3
Warrant liabilities 47.7 89.4
Other long-term liabilities 13.9 12.8
Total liabilities 203.3 248.6
Commitments and contingencies (Note 7)
Stockholders’ equity    
Preferred stock, $0.0001 par value; 10,000,000 shares authorized; no shares issued and outstanding as of March 31, 2025 and December 31, 2024 0.0 0.0
Additional paid-in capital 2,790.4 2,438.4
Accumulated deficit (1,779.0) (1,685.6)
Accumulated other comprehensive loss (0.2) (0.3)
Total stockholders’ equity 1,011.3 752.6
Total liabilities and stockholders’ equity 1,214.6 1,001.2
Class A    
Stockholders’ equity    
Common stock 0.1 0.1
Class B    
Stockholders’ equity    
Common stock $ 0.0 $ 0.0
v3.25.1
Consolidated Condensed Balance Sheets (Parenthetical) - $ / shares
Mar. 31, 2025
Dec. 31, 2024
Preferred stock, par value (in dollars per share) $ 0.0001 $ 0.0001
Preferred stock, authorized (in shares) 10,000,000 10,000,000
Preferred stock, issued (in shares) 0 0
Preferred stock, outstanding (in shares) 0 0
Class A    
Common stock, par value (in dollars per share) $ 0.0001 $ 0.0001
Common stock, authorized (in shares) 1,400,000,000 1,400,000,000
Common stock, issued (in shares) 548,881,477 503,777,464
Common stock, outstanding (in shares) 548,881,477 503,777,464
Class B    
Common stock, par value (in dollars per share) $ 0.0001 $ 0.0001
Common stock, authorized (in shares) 300,000,000 300,000,000
Common stock, issued (in shares) 0 0
Common stock, outstanding (in shares) 0 0
v3.25.1
Consolidated Condensed Statements of Operations - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Operating expenses    
Research and development $ 103.7 $ 83.5
General and administrative 40.3 58.7
Total operating expenses 144.0 142.2
Loss from operations (144.0) (142.2)
Other income, net 42.0 20.6
Interest income, net 8.7 5.3
Loss before income taxes (93.3) (116.3)
Income tax expense (0.1) (0.2)
Net loss $ (93.4) $ (116.5)
Net loss per share, basic (in dollars per share) $ (0.17) $ (0.36)
Net loss per share, diluted (in dollars per share) $ (0.17) $ (0.36)
Weighted-average shares outstanding, basic (in shares) 540,427,085 320,256,596
Weighted-average shares outstanding, diluted (in shares) 540,427,085 320,256,596
v3.25.1
Consolidated Condensed Statements of Comprehensive Loss - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Statement of Comprehensive Income [Abstract]    
Net loss $ (93.4) $ (116.5)
Other comprehensive income:    
Foreign currency translation adjustment 0.1 0.0
Comprehensive loss $ (93.3) $ (116.5)
v3.25.1
Consolidated Condensed Statements of Stockholders’ Equity - USD ($)
$ in Millions
Total
Additional Paid-in Capital
Accumulated Deficit
Accumulated Other Comprehensive Loss
Class A
Class A
Common Stock
Class B
Class B
Common Stock
Common stock, beginning balance (in shares) at Dec. 31, 2023           265,617,341   38,165,615
Beginning balance at Dec. 31, 2023 $ 367.1 $ 1,515.9 $ (1,148.8) $ 0.0   $ 0.0   $ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Conversion of Class B common stock to Class A common stock (in shares)           200,000   (200,000)
Issuance of restricted stock units and restricted stock expense (in shares)           4,873,123    
Issuance of restricted stock units and restricted stock expense 34.0 34.0            
Exercise of stock options (in shares)           186,529   66,760
Exercise of stock options 0.0              
Issuance of warrants and warrant expense 48.9 48.9            
Exercise of warrants (in shares)           4,503,845    
Exercise of warrants 0.0              
Common stock issued under at-the-market program (in shares)           6,569,896    
Common stock issued under at-the-market program 33.9 33.9            
Stock-based compensation 11.8 11.8            
Net loss (116.5)   (116.5)          
Common stock, ending balance (in shares) at Mar. 31, 2024           281,950,734   38,032,375
Ending balance at Mar. 31, 2024 379.2 1,644.5 (1,265.3) 0.0   $ 0.0   $ 0.0
Common stock, beginning balance (in shares) at Dec. 31, 2024         503,777,464 503,777,464 0  
Beginning balance at Dec. 31, 2024 752.6 2,438.4 (1,685.6) (0.3)   $ 0.1    
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Issuance of Class A common stock (in shares)           1,906,161    
Issuance of Class A common stock 16.7 16.7            
Issuance of restricted stock units and restricted stock expense (in shares)           4,544,253    
Issuance of restricted stock units and restricted stock expense $ 1.9 1.9            
Exercise of stock options (in shares) 168,509         168,510    
Exercise of stock options $ 0.0              
Issuance of warrants and warrant expense 0.8 0.8            
Exercise of warrants (in shares)           3,000    
Exercise of warrants 0.0              
PIPE financing (in shares)           2,982,089    
PIPE financing 9.6 9.6            
Registered direct offering (in shares)           35,500,000    
Registered direct offering 289.5 289.5            
Stock-based compensation 33.5 33.5            
Net loss (93.4)   (93.4)          
Other comprehensive income 0.1     0.1        
Common stock, ending balance (in shares) at Mar. 31, 2025         548,881,477 548,881,477 0  
Ending balance at Mar. 31, 2025 $ 1,011.3 $ 2,790.4 $ (1,779.0) $ (0.2)   $ 0.1    
v3.25.1
Consolidated Condensed Statements of Cash Flows - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Cash flows from operating activities    
Net loss $ (93.4) $ (116.5)
Adjustments to reconcile net loss to net cash used in operating activities:    
Depreciation and amortization expense 4.1 2.3
Stock-based compensation 30.1 40.7
Change in fair value of warrant liabilities (41.7) (20.8)
Non-cash lease expense 0.8 0.7
Research and development warrant expense 0.8 2.1
Technology and dispute resolution agreements expense 0.0 5.6
Changes in operating assets and liabilities:    
Prepaid expenses (1.6) 0.2
Other current assets (1.2) (1.1)
Other long-term assets (1.7) (0.6)
Accounts payable 0.5 0.0
Accrued expenses and other current liabilities 8.1 1.7
Operating lease right-of-use assets and lease liabilities, net (1.0) (0.8)
Other long-term liabilities 1.6 0.0
Net cash used in operating activities (94.6) (86.5)
Cash flows from investing activities    
Purchase of property and equipment (10.0) (17.3)
Net cash used in investing activities (10.0) (17.3)
Cash flows from financing activities    
Proceeds from issuance of debt 0.0 11.0
Payment of debt issuance costs 0.0 (0.1)
Proceeds from PIPE financing 10.0 0.0
Proceeds from registered direct offering 301.8 0.0
Proceeds from shares issued under at-the-market program 0.0 33.9
Payment of offering costs in connection with financing activities (11.6) 0.0
Net cash provided by financing activities 300.2 44.8
Net increase (decrease) in cash, cash equivalents, and restricted cash 195.6 (59.0)
Cash, cash equivalents, and restricted cash, beginning of period 841.3 471.5
Cash, cash equivalents, and restricted cash, end of period 1,036.9 412.5
Supplemental Cash Flow Information:    
Cash paid for interest 1.0 0.2
Non-cash investing and financing activities:    
Purchases of property and equipment included in accounts payable and accrued expenses 6.7 10.0
Payment of offering costs in connection with financing activities in common stock $ 1.2 $ 0.0
v3.25.1
Organization and Nature of Business
 3 Months Ended
Mar. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Organization and Nature of Business Organization and Nature of Business
Organization and Nature of Business
Archer Aviation Inc. (the “Company”), a Delaware corporation, with its headquarters located in San Jose, California, is an
aerospace company. The Company is developing technologies and aircraft that will power the future of advanced aviation. The
Company’s primary product is an electric vertical take-off and landing (“eVTOL”) aircraft.
The Company’s Planned Lines of Business
The Company intends to operate the following lines of business:
Commercial
This is planned to consist of the sale of the Company’s commercial aircraft (“Archer Direct”), such as Midnight, as well as technologies and services related thereto, and direct-to-consumer aerial ride share services in select metropolitan areas around the world (“Archer UAM”).
Defense
This is planned to consist of the sale of next-generation aircraft, related technologies and support services for defense applications.
v3.25.1
Liquidity and Going Concern
 3 Months Ended
Mar. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Liquidity and Going Concern Liquidity and Going Concern
Since the Company’s formation, the Company has devoted substantial effort and capital resources to the design and development of its planned aircraft, UAM network and business lines. Funding of these activities has primarily been through the net proceeds received from the issuance of related and third-party debt (Note 6 - Notes Payable), and the sale of preferred and common stock to related and third parties (Note 8 - Preferred and Common Stock). Through March 31, 2025, the Company has incurred cumulative losses from operations, negative cash flows from operating activities, and has an accumulated deficit of $1,779.0 million. As of March 31, 2025, the Company had cash and cash equivalents of $1,030.4 million, which management believes will be sufficient to fund the Company’s current operating plan for at least the next 12 months from the date these consolidated condensed financial statements were issued.
There can be no assurance that the Company will be successful in achieving its business plans, that the Company’s current capital will be sufficient to support its ongoing business plans, or that any additional financing will be available in a timely manner or on acceptable terms, if at all. If the Company’s business plans require it to raise additional capital, but the Company is unable to do so, it may be required to alter, or scale back its aircraft design, development and certification programs, as well as its manufacturing capabilities, or be unable to fund capital expenditures. Any such events would have a material adverse effect on the Company’s financial position, results of operations, cash flows, and ability to achieve the Company’s intended business plans.
v3.25.1
Summary of Significant Accounting Policies
 3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies Summary of Significant Accounting Policies
Basis of Presentation
The accompanying unaudited consolidated condensed financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial information. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States (“U.S. GAAP”) for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring adjustments, necessary for a fair statement of financial position, results of operations, and cash flows for the interim periods presented have been reflected herein. The results of operations for interim periods are not necessarily indicative of the results to be expected for the full year. The unaudited consolidated condensed financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of and for the fiscal year ended December 31, 2024 set forth in the Company’s Annual Report on Form 10-K filed with the SEC on February 27, 2025. The December 31, 2024 consolidated condensed balance sheet was derived from audited financial statements but does not include all disclosures required by U.S. GAAP.
The Company has provided a discussion of significant accounting policies, estimates, and judgments in the Company’s audited consolidated financial statements. There have been no changes to the Company’s significant accounting policies since December 31, 2024 which are expected to have a material impact on the Company’s financial position, results of operations, or cash flows.
Cash, Cash Equivalents, and Restricted Cash
Cash consists of cash on deposit with financial institutions. Cash equivalents consist of short-term, highly liquid financial instruments that are readily convertible to cash and have maturities of three months or less from the date of purchase. As of March 31, 2025 and December 31, 2024, the Company’s cash and cash equivalents included money market funds of $906.0 million and $729.9 million, respectively.
Restricted cash consists primarily of cash held as security for the Company’s standby letters of credit. Refer to Note 7 - Commitments and Contingencies for additional information.
The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported in the consolidated condensed balance sheets that sum to amounts reported on the consolidated condensed statements of cash flows (in millions):
March 31,
2025		December 31,
2024
Cash and cash equivalents$1,030.4 $834.5 
Restricted cash6.5 6.8 
Total cash, cash equivalents, and restricted cash$1,036.9 $841.3 
Fair Value Measurements
The Company applies the provisions of Accounting Standards Codification (“ASC”) 820, Fair Value Measurement, which defines a single authoritative definition of fair value, sets out a framework for measuring fair value, and expands on required disclosures about fair value measurements. The provisions of ASC 820 relate to financial assets and liabilities as well as other assets and liabilities carried at fair value on a recurring and nonrecurring basis. The standard clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the standard establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows:
Level 1Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.
Level 2Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability.
Level 3Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at the measurement date.
The carrying amounts of the Company’s cash, prepaid expenses, other current assets, accounts payable, accrued compensation, and accrued liabilities approximate their fair values due to the short-term nature of these instruments.
The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2025 and December 31, 2024 and indicate the fair value hierarchy of the valuation inputs the Company utilized to determine such fair value (in millions):
As of March 31, 2025
DescriptionLevel 1Level 2Level 3Total
Assets:
Cash equivalents:
Money market funds$906.0 $— $— $906.0 
Liabilities:
Warrant liability – public warrants$31.3 $— $— $31.3 
Warrant liability – private placement warrants$— $— $16.4 $16.4 
As of December 31, 2024
DescriptionLevel 1Level 2Level 3Total
Assets:
Cash equivalents:
Money market funds$729.9 $— $— $729.9 
Liabilities:
Warrant liability – public warrants$56.0 $— $— $56.0 
Warrant liability – private placement warrants$— $— $33.4 $33.4 
Cash Equivalents
The Company’s cash equivalents consist of short-term, highly liquid financial instruments that are readily convertible to cash and have maturities of three months or less from the date of purchase. The Company classifies its money market funds as Level 1, because they are valued based on quoted market prices in active markets.
The following table presents a summary of the Company’s cash equivalents as of March 31, 2025 and December 31, 2024 (in millions):
As of March 31, 2025
DescriptionAmortized CostUnrealized GainsUnrealized LossesFair Value
Cash equivalents:
Money market funds$906.0 $— $— $906.0 
Total$906.0 $— $— $906.0 
As of December 31, 2024
DescriptionAmortized CostUnrealized GainsUnrealized LossesFair Value
Cash equivalents:
Money market funds$729.9 $— $— $729.9 
Total$729.9 $— $— $729.9 
Public Warrants
The measurement of the public warrants as of March 31, 2025 is classified as Level 1 due to the use of an observable market quote in an active market under the ticker “ACHR WS”. The quoted price of the public warrants was $1.80 and $3.22 per warrant as of March 31, 2025 and December 31, 2024, respectively.
Private Placement Warrants
The Company utilizes a Monte Carlo simulation model for the private placement warrants at each reporting period, with changes in fair value recognized in the consolidated condensed statements of operations. The estimated fair value of the private placement warrant liability is determined using Level 3 inputs. Inherent in a Monte Carlo simulation model are assumptions related to expected share-price volatility, expected life, risk-free interest rate, and dividend yield.
The key inputs into the Monte Carlo simulation model for the private placement warrants are as follows:
InputMarch 31,
2025		December 31,
2024
Stock price$7.11 $9.75 
Strike price$11.50 $11.50 
Term (in years)1.51.7
Risk-free rate3.9 %4.2 %
Volatility88.9 %92.1 %
Dividend yield0.0 %0.0 %
The following table presents the change in fair value of the Company’s Level 3 private placement warrants during the three months ended March 31, 2025 (in millions):

Balance as of December 31, 2024
$33.4 
Change in fair value(17.0)
Balance as of March 31, 2025
$16.4 
In connection with the change in fair value of the Company’s private placement warrants, the Company recognized a gain of $17.0 million and $7.9 million within other income, net in the consolidated condensed statements of operations during the three months ended March 31, 2025 and 2024, respectively. Refer to Note 11 - Liability Classified Warrants for additional information about the private placement warrants.
Financial Instruments Not Recorded at Fair Value on a Recurring Basis
Certain financial instruments, including debt, are not measured at fair value on a recurring basis in the consolidated condensed balance sheets. The fair value of debt as of March 31, 2025 approximates its carrying value (Level 2). Refer to Note 6 - Notes Payable for additional information.
Assets and Liabilities Recorded at Fair Value on a Non-Recurring Basis
Certain assets and liabilities are subject to measurement at fair value on a non-recurring basis if there are indicators of impairment or if they are deemed to be impaired as a result of an impairment review.
Intangible Assets, Net
Intangible assets consist solely of domain names and are recorded at cost, net of accumulated amortization, and if applicable, impairment charges. Amortization of domain names is provided over a 15-year estimated useful life on a straight-line basis or based on the pattern in which economic benefits are consumed, if reliably determinable. The Company reviews intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company has analyzed a variety of factors to determine if any circumstance could trigger an impairment loss, and, at this time and based on the information presently known, no event has occurred and indicated that it is more likely than not that an impairment loss has been incurred. Therefore, the Company did not record any impairment charges for its intangible assets for the three months ended March 31, 2025 and 2024.
As of March 31, 2025 and December 31, 2024, the net carrying amounts for domain names were $0.3 million and $0.3 million, respectively, and were recorded in the Company’s consolidated condensed balance sheets.
Cloud Computing Arrangements
The Company capitalizes certain implementation costs incurred in the application development stage of projects related to its cloud computing arrangements that are service contracts. Capitalized implementation costs are recognized in other long-term assets in the consolidated condensed balance sheets and amortized on a straight-line basis over the fixed, noncancellable term of the associated hosting arrangement plus any reasonably certain renewal periods. Costs related to preliminary project activities and post-implementation activities are expensed as incurred. As of March 31, 2025 and December 31, 2024, the net carrying amounts of the Company’s capitalized cloud computing implementation costs were $6.3 million and $5.9 million, respectively.
Contract Liabilities
The Company records contract liabilities related to differences between the timing of cash receipts from the customer and the recognition of revenue. Contract liabilities consisted of the following (in millions):
March 31,
2025		December 31,
2024
Current portion of contract liabilities
$0.9 $0.9 
Contract liabilities, net of current portion13.3 11.8 
Total
$14.2 $12.7 
Current portion of contract liabilities is recorded in accrued expenses and other current liabilities and contract liabilities, net of current portion is recorded in other long-term liabilities in the Company’s consolidated condensed balance sheets. As of March 31, 2025 and December 31, 2024, the Company’s contract liabilities primarily consisted of a $10.0 million pre-delivery payment received from United Airlines, Inc. (“United”) under the terms of the Amended United Purchase Agreement (defined below) (see Note 9 - Stock-Based Compensation), and installment payments received under a contract order with the United States Air Force for the design, development, and ground test of the Company’s production aircraft, Midnight, of $3.3 million and $1.8 million, respectively. No revenues were recognized during the three months ended March 31, 2025 and 2024.
Net Loss Per Share
Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding. For all periods presented, the calculation of basic net loss per share excludes shares issued upon the early exercise of stock options where the vesting conditions have not been satisfied. Common stock purchased pursuant to an early exercise of stock options is not deemed to be outstanding for accounting purposes until those shares vest. The Company also excludes unvested shares subject to repurchase in the number of shares outstanding in the consolidated condensed balance sheets and statements of stockholders’ equity.
Because the Company reported net losses for all periods presented, diluted loss per share is the same as basic loss per share.
Contingently issuable shares, including equity awards with performance conditions, are considered outstanding common shares and included in the computation of basic net loss per share as of the date that all necessary conditions to earn the awards have been satisfied.
The following table presents the number of antidilutive shares excluded from the calculation of diluted net loss per share:
Three Months Ended March 31,
20252024
Options to purchase common stock1,871,637 2,915,738 
Unvested restricted stock units31,685,118 35,015,943 
Warrants33,344,301 47,011,560 
Shares issuable under the Employee Stock Purchase Plan (Note 9)
688,280 1,091,452 
Total67,589,336 86,034,693 
Segments
The following table presents significant expenses provided to the Chief Operating Decision Maker (in millions):
Three Months Ended March 31,
20252024
Operating expenses
Depreciation and amortization expense
$4.1 $2.3 
Research and development warrant expense
0.8 2.1 
Stock-based compensation
30.1 40.7 
Technology and dispute resolution agreements expense
— 10.3 
Other research and development expense
88.2 67.1 
Other general and administrative expense
20.8 19.7 
Total operating expenses144.0 142.2 
Loss from operations(144.0)(142.2)
Other income, net42.0 20.6 
Interest income, net8.7 5.3 
Loss before income taxes(93.3)(116.3)
Income tax expense(0.1)(0.2)
Net loss$(93.4)$(116.5)
Comprehensive Loss
Comprehensive loss includes all changes in equity during the period from non-owner sources. The Company’s comprehensive loss consists of its net loss and foreign currency translation adjustment.
Recent Accounting Pronouncements
Recently Issued Accounting Pronouncements Not Yet Adopted
In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires disclosure of incremental income tax information related to the income tax rate reconciliation and expanded disclosures of income taxes paid, among other disclosure requirements. The update is effective for annual periods beginning after December 15, 2024 on a prospective basis, and retrospective application is permitted. The Company is currently evaluating the impact of ASU 2023-09 on its disclosures within its consolidated financial statements.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which requires disclosure of additional information about specific expense categories in the notes to the financial statements. The update is effective for annual periods beginning after December 15, 2026, and interim periods within annual periods beginning after December 15, 2027. Early adoption is permitted. The update can be applied either (1) prospectively to financial statements issued for reporting periods after the effective date or (2) retrospectively to any of all prior periods presented in the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its disclosures within its consolidated financial statements.
v3.25.1
Property and Equipment, Net
 3 Months Ended
Mar. 31, 2025
Property, Plant and Equipment [Abstract]  
Property and Equipment, Net Property and Equipment, Net
Property and equipment, net, consisted of the following (in millions):
March 31,
2025		December 31,
2024
Building$67.3 $64.4 
Furniture, fixtures, and equipment29.3 24.7 
Vehicles0.9 0.1 
Computer hardware6.0 5.8 
Computer software2.0 1.9 
Website design0.8 0.8 
Building and leasehold improvements36.9 34.2 
Construction in progress11.0 13.3 
Total property and equipment154.2 145.2 
Less: Accumulated depreciation(22.1)(18.4)
Total property and equipment, net$132.1 $126.8 
The following table presents depreciation expense included in each respective expense category in the consolidated condensed statements of operations (in millions):
Three Months Ended March 31,
20252024
Research and development$3.6 $2.0 
General and administrative0.1 0.1 
Total depreciation expense$3.7 $2.1 
v3.25.1
Accrued Expenses and Other Current Liabilities
 3 Months Ended
Mar. 31, 2025
Other Liabilities Disclosure [Abstract]  
Accrued Expenses and Other Current Liabilities Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following (in millions):
March 31,
2025		December 31,
2024
Accrued professional fees$10.8 $6.5 
Accrued employee costs11.2 22.2 
Accrued parts and materials15.9 12.5 
Current portion of contract liabilities0.9 0.9 
Other current liabilities9.8 10.7 
Total$48.6 $52.8 
v3.25.1
Notes Payable
 3 Months Ended
Mar. 31, 2025
Debt Disclosure [Abstract]  
Notes Payable Notes Payable
Notes payable consisted of the following (in millions):
March 31,
2025		December 31,
2024
Synovus Bank Loan$65.0 $65.0 
Loan unamortized discount and loan issuance costs(0.9)(1.0)
Total debt, net of discount and loan issuance costs64.1 64.0 
Less current portion, net of discount and loan issuance costs— — 
Total long-term notes payable, net of discount and loan issuance costs$64.1 $64.0 
On October 5, 2023, the Company entered into a credit agreement (the “Credit Agreement”) with Synovus Bank, as administrative agent and lender, and the additional lenders (the “Lenders”) from time to time, in an aggregate principal amount of up to $65.0 million for the construction and development of the Company’s manufacturing facility in Covington, Georgia (the “Loan”).
The Company is required to make 120 monthly interest payments from November 14, 2023 until maturity, and 84 equal monthly principal installments from November 14, 2026 until maturity. The Credit Agreement matures on the earlier of October 5, 2033 or the date on which the outstanding Loan has been declared or automatically becomes due and payable pursuant to the terms of the Credit Agreement.
The interest rate on the Loan is a floating rate per annum equal to secured overnight financing rate (as defined in the Credit Agreement) plus the applicable margin of 2.0%, which increases by 5.0% per annum upon the occurrence of an event of default.
The Company’s obligations under the Credit Agreement are secured by funds in a collateral account and the Credit Agreement is guaranteed by the Company’s domestic subsidiaries. The Company may prepay with certain premium that links to the passage of time, and in certain circumstances would be required to prepay the Loan under the Credit Agreement without payment of a premium. The Credit Agreement contains customary representations and warranties, customary affirmative and negative covenants, and customary events of default. As of March 31, 2025, the Company was in compliance with all the covenants of the Credit Agreement.
The Company has drawn down the full $65.0 million of the Loan as of March 31, 2025. The effective interest rate for the draw downs ranged from 6.6% to 7.1% and 6.7% to 7.2% as of March 31, 2025 and December 31, 2024, respectively. During the three months ended March 31, 2025 and 2024, the Company recognized interest expense of $1.1 million and $0.3 million, respectively, including an immaterial amount related to the amortization of issuance costs within interest income, net in the consolidated condensed statements of operations. The carrying value of the Loan, net of unamortized issuance costs of $0.9 million, was $64.1 million as of March 31, 2025.
The future scheduled principal maturities of the Loan as of March 31, 2025 are as follows (in millions):

Remaining 2025
$— 
2026
0.4 
2027
2.6 
2028
2.6 
2029
2.6 
Thereafter56.8 
$65.0 
v3.25.1
Commitments and Contingencies
 3 Months Ended
Mar. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Operating Leases
The Company leases office, lab, hangar, and storage facilities under various operating lease agreements with lease periods expiring between 2025 and 2030 and generally containing periodic rent increases and various renewal and termination options.
The Company’s lease costs were as follows (in millions):
Three Months Ended March 31,
20252024
Operating lease cost$1.3 $1.2 
Short-term lease cost0.1 0.1 
Total lease cost$1.4 $1.3 
The Company’s weighted-average remaining lease term and discount rate as of March 31, 2025 and 2024 were as follows:
20252024
Weighted-average remaining lease term (in months)4653
Weighted-average discount rate14.4 %14.6 %
The minimum aggregate future obligations under the Company’s non-cancelable operating leases as of March 31, 2025 were as follows (in millions):
Remaining 2025
$4.7 
20265.5 
20272.9 
20282.2 
20292.3 
Thereafter2.1 
Total future lease payments19.7 
Less: leasehold improvement allowance(0.5)
Total net future lease payments19.2 
Less: imputed interest(5.0)
Present value of future lease payments$14.2 
Supplemental cash flow information and non-cash activities related to right-of-use assets and lease liabilities were as follows (in millions):
Three Months Ended March 31,
20252024
Operating cash outflows from operating leases$1.5 $1.1 
Operating lease liabilities from obtaining right-of-use assets$0.2 $0.3 
Finance Lease
In February 2023, the Company entered into a lease arrangement with the Newton County Industrial Development Authority (the “Authority”) for the Company’s manufacturing facilities to be constructed in Covington, Georgia. In connection with the lease arrangement, the Authority issued a taxable revenue bond (the “Bond”), which was acquired by the Company. The arrangement is structured so that the Company’s lease payments to the Authority equal and offset the Authority’s bond payments to the Company. Accordingly, the Company offsets the finance lease obligation and the Bond on its consolidated condensed balance sheets.
Letters of Credit
As of March 31, 2025, the Company had standby letters of credit in the aggregate outstanding amount of $5.5 million, secured with restricted cash.
Litigation
During the ordinary course of the business, the Company may be subject to legal proceedings, various claims, and litigation. Such proceedings can be costly, time consuming, and unpredictable, and therefore, no assurance can be given that the final outcome of such proceedings will not materially impact the Company’s financial condition or results of operations.
Delaware Class Action Litigation
On May 17, 2024, two putative stockholders of the Company (and formerly, Atlas Crest Investment Corp. (“Atlas”)) filed class action lawsuits, on behalf of themselves and other similarly-situated stockholders, in the Delaware Court of Chancery against the directors and officers of Atlas, the Company, the Company’s co-founders, Moelis & Company Group LP and Moelis & Company LLC. The complaint asserts claims against the defendants for breaches of fiduciary duties, aiding and abetting breaches of fiduciary duties, and unjust enrichment, in connection with the merger between Atlas and the Company. The plaintiffs request damages in an amount to be determined at trial, as well as attorneys’ and experts’ fees. Relatedly, on June 19, 2024, another putative stockholder of the Company filed a class action lawsuit, on behalf of himself and other similarly-situated stockholders, in the Delaware Court of Chancery asserting similar claims as the aforementioned May 17, 2024 complaint against the same defendants named in that May complaint. The Delaware Court of Chancery subsequently consolidated the related class actions and appointed a lead plaintiff. The Company along with the other defendants filed a motion to dismiss on October 3, 2024. The plaintiffs filed an answer on January 13, 2025. A hearing on that motion to dismiss was held on April 17, 2025, but the court has yet to issue a ruling.
v3.25.1
Preferred and Common Stock
 3 Months Ended
Mar. 31, 2025
Equity [Abstract]  
Preferred and Common Stock Preferred and Common Stock
Preferred Stock
As of March 31, 2025, no shares of preferred stock were outstanding, and the Company has no present plans to issue any shares of preferred stock.
Voting
Holders of the Company’s Class A common stock are entitled to one vote per share on all matters to be voted upon by the stockholders.
Dividends
Holders of Class A common stock are entitled to receive such dividends, if any, as may be declared from time to time by the Company’s Board of Directors in its discretion out of funds legally available therefor. No dividends on common stock have been declared by the Company’s Board of Directors through March 31, 2025, and the Company does not expect to pay dividends in the foreseeable future.
Preemptive Rights
Stockholders have no preemptive or other subscription rights and there are no sinking fund or redemption provisions applicable to Class A common stock.
Liquidation
In the event of the Company’s voluntary or involuntary liquidation, dissolution, distribution of assets or winding-up, subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of the Company’s common stock will be entitled to receive an equal amount per share of all of the Company’s assets of whatever kind available for distribution to stockholders, after the rights of the holders of any preferred stock have been satisfied.
PIPE Financings
On August 8, 2024, the Company entered into subscription agreements with certain investors providing for the private placement of the Company’s Class A common stock at a purchase price of $3.35 per share (the “First 2024 PIPE Financing”), pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”). A portion of the First 2024 PIPE Financing closed on August 12, 2024 for 49,283,582 shares of the Company’s Class A common stock for net proceeds of approximately $158.0 million, after deducting offering costs. The remaining portion of the First 2024 PIPE Financing covering an aggregate of 2,982,089 shares of the Company’s Class A common stock issued and sold to Stellantis N.V. (“Stellantis”) closed on January 6, 2025 for net proceeds of approximately $9.6 million, after deducting offering costs.
On December 11, 2024, the Company entered into subscription agreements with certain investors providing for the private placement of the Company’s Class A common stock at a purchase price of $6.65 per share (the “Second 2024 PIPE Financing”), pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act. A portion of the Second 2024 PIPE Financing closed on December 13, 2024 for 63,909,776 shares of the Company’s Class A common stock for net proceeds of approximately $407.7 million, after deducting offering costs. The remaining portion of the Second 2024 PIPE Financing covering an aggregate of 751,879 shares of the Company’s Class A common stock to be issued and sold to Stellantis for anticipated gross proceeds of approximately $5.0 million is subject to the satisfaction of certain closing conditions, including approval by the Company’s stockholders.
At-The-Market Program
In November 2024, the Company filed a shelf registration statement on Form S-3ASR with the SEC and a related prospectus for the sale under a Controlled Equity OfferingSM Sales Agreement (the “ATM Sales Agreement”) of shares of its Class A common stock, having an aggregate value of up to $70.0 million (the “ATM Program”). The Company pays the placement agent a commission rate of up to 3.0% of the gross proceeds from any shares of Class A common stock sold through the ATM Sales Agreement. During the three months ended March 31, 2025, the Company did not sell any shares of Class A common stock under the ATM Program. As of March 31, 2025, the Company had $47.5 million remaining eligible for sales under the ATM Program.
Registered Direct Offering
On February 12, 2025, the Company closed a registered direct offering in which pursuant to the securities purchase agreement dated February 11, 2025, by and between the Company and certain institutional investors, the Company issued and sold 35,500,000 shares of the Company’s Class A common stock for net proceeds of approximately $289.5 million, after deducting offering costs.
v3.25.1
Stock-Based Compensation​
 3 Months Ended
Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Stock-Based Compensation​ Stock-Based Compensation
Amended and Restated 2021 Plan
In August 2021, the Company adopted the 2021 Equity Incentive Plan (the “2021 Plan”), which was approved by the stockholders of the Company in September 2021 and became effective immediately upon the closing of the Business Combination. In April 2022, the Company amended and restated the 2021 Plan (the “Amended and Restated 2021 Plan”), which was approved by the stockholders of the Company in June 2022. The aggregate number of shares of Class A common stock that may be issued under the plan increased to 34,175,708. In addition, the number of shares of Class A common stock reserved for issuance under the Amended and Restated 2021 Plan will automatically increase on January 1st of each year following this amendment, starting on January 1, 2023 and ending on (and including) January 1, 2031, in an amount equal to the lesser of (i) 5.0% of the total number of shares of Class A and Class B common stock outstanding on December 31 of the preceding year, or (ii) a lesser number of shares of Class A common stock determined by the Board of Directors prior to the date of the increase (the “EIP Evergreen Provision”). The EIP Evergreen Provision is calculated using the number of legally outstanding shares of common stock and includes shares, such as unvested shares pursuant to early exercised stock options, that are not considered outstanding for accounting purposes. In accordance therewith, the number of shares of Class A common stock reserved for issuance under the Amended and Restated 2021 Plan increased by 25,191,478 shares on January 1, 2025. The Amended and Restated 2021 Plan provides for the grant of incentive and non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock units, performance awards, and other awards to employees, directors, and non-employees.
In connection with the adoption of the 2021 Plan, the Company ceased issuing awards under its 2019 Equity Incentive Plan (the “2019 Plan”). Following the closing of the Business Combination, the Company assumed the outstanding stock options under the 2019 Plan and converted such stock options into options to purchase the Company’s common stock. Such stock options will continue to be governed by the terms of the 2019 Plan and the stock option agreements thereunder, until such outstanding options are exercised or until they terminate or expire.
Employee Stock Purchase Plan
In August 2021, the Company adopted the 2021 Employee Stock Purchase Plan (the “ESPP”), which became effective immediately upon the closing of the Business Combination. The ESPP permits eligible employees to purchase shares of Class A common stock at a price equal to 85.0% of the lower of the fair market value of Class A common stock on the first day of an offering or on the date of purchase. Additionally, the number of shares of Class A common stock reserved for issuance under the ESPP will automatically increase on January 1st of each year, beginning on January 1, 2022 and continuing through and including January 1, 2031, by the lesser of (i) 1.0% of the total number of shares of Class A common stock outstanding on December 31 of the preceding year; (ii) 9,938,118 shares of Class A common stock; or (iii) a lesser number of shares of Class A common stock determined by the Board of Directors prior to the date of the increase (the “ESPP Evergreen Provision”). The ESPP Evergreen Provision is calculated using the number of legally outstanding shares of common stock and includes shares, such as unvested shares pursuant to early exercised stock options, that are not considered outstanding for accounting purposes. In accordance therewith, the number of shares of Class A common stock reserved for issuance under the ESPP increased by 4,677,185 on January 1, 2025. As of March 31, 2025, the maximum number of shares authorized for issuance under the ESPP was 15,762,995, of which 12,810,367 shares remained available under the ESPP.
The Company currently offers six-month offering periods, and at the end of each offering period, which occurs every six months on May 31 and November 30, employees can elect to purchase shares of the Company’s Class A common stock with contributions of up to 15.0% of their base pay, accumulated via payroll deductions, subject to certain limitations.
The Company uses the Black-Scholes option pricing model to calculate the grant date fair value of each award granted under the ESPP. The following table sets forth the key assumptions and fair value results for each award granted in the Company’s six-month offering period that started on December 1, 2024:
December 1, 2024
Stock price$9.57 
Term (in years)0.5
Risk-free interest rate4.4 %
Volatility85.0 %
Dividend yield0.0 %
Grant date fair value per share$3.67 
During the three months ended March 31, 2025 and 2024, the Company recognized stock-based compensation expense of $0.9 million and $0.7 million for the ESPP, respectively.
As of March 31, 2025, the total remaining stock-based compensation expense was $0.6 million for the ESPP, which is expected to be recognized over the current six-month offering period until May 31, 2025.
Annual Equity Awards
Subject to the achievement of certain performance goals established by the Company from time to time, the Company’s employees are eligible to receive an annual incentive bonus that will entitle them to an annual grant of restricted stock units (“RSUs”) that are fully vested on the date of grant. Furthermore, all annual equity awards are contingent and issued only upon approval by the Company’s Board of Directors or the Compensation Committee. During the three months ended March 31, 2025 and 2024, the Company recognized stock-based compensation expense of $3.8 million and $3.8 million, respectively, related to these annual equity awards.
Stock Options
A summary of the Company’s stock option activity is as follows:
Number of
Shares
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Life (Years)
Aggregate
Intrinsic
Value
(In millions)
Outstanding as of January 1, 20252,118,011 $0.13 5.8$20.4 
Exercised(168,509)$0.10 $1.5 
Expired/forfeited(77,865)$0.15 
Outstanding as of March 31, 2025
1,871,637 $0.14 5.6$13.1 
Exercisable as of March 31, 2025
1,494,201 $0.13 5.5$10.4 
Vested and expected to vest as of March 31, 2025
1,871,637 $0.14 5.6$13.1 
The Company recognized stock-based compensation expense of $0.6 million and $0.8 million for stock options for the three months ended March 31, 2025 and 2024, respectively.
As of March 31, 2025, the total remaining stock-based compensation expense for unvested stock options was $1.6 million, which is expected to be recognized over a weighted-average period of 0.3 years.
Restricted Stock Units
A summary of the Company’s RSU activity is as follows:
Number of
Shares
Weighted
Average
Grant Fair Value
Outstanding as of January 1, 202528,658,246 $5.02 
Granted7,906,872 $9.51 
Performance based adjustment (1)
190,844 $6.39 
Vested(4,578,181)$6.30 
Forfeited(492,663)$5.49 
Outstanding as of March 31, 2025
31,685,118 $5.96 
(1) Represents units adjusted for the vesting of the first tranche of PSUs (defined below) granted in 2024.
During the three months ended March 31, 2025, the Company granted 1,897,941 RSUs under the Amended and Restated 2021 Plan, representing the annual equity awards for 2024. The RSUs were fully vested on the date of grant and settled in Class A common stock on a one-for-one basis. In addition, the Company granted 5,487,006 RSUs under the Amended and Restated 2021 Plan, which generally vest over a three-year period with a one-year cliff and remain subject to forfeiture if vesting conditions are not met. Upon vesting, RSUs are settled in Class A common stock on a one-for-one basis. The shares of Class A common stock underlying RSU grants are not issued and outstanding until the applicable vesting date.
During the three months ended March 31, 2025, the Company granted 521,925 RSUs under the Amended and Restated 2021 Plan to certain executives, which vest over a three-year period with a payout based on the Company’s relative performance of total shareholder return (“TSR”) compared with the annualized TSR of certain peer companies for the service period (the “PSUs”). The award payout can range from 0.0% to 200.0% of the initial grant, and is measured on each anniversary of the grant date. Upon vesting, the PSUs are settled in Class A common stock on a one-for-one basis. If an executive’s employment ends due to disability, death, termination without cause or resignation for good reason, the executive (or beneficiary) remains eligible under the award and, if the award is earned, will receive a proration of PSUs based on active employment during the annual service periods. In all other cases, the award will not vest and all rights to the PSUs will terminate.
The Company determined the fair value of the PSUs using a Monte Carlo simulation model on the grant date. The Company will recognize compensation expense for the PSUs on a straight-line basis over the three-year performance period.
The following assumptions were used to estimate the fair value, using the Monte Carlo simulation, of the PSUs:
February 17, 2025
Stock price$10.35 
Term (in years)3.0
Risk-free interest rate4.2 %
Volatility88.2 %
Dividend yield0.0 %
Immediately prior to closing of the Business Combination, each of the Company’s founders was granted 20,009,224 RSUs under the 2019 Plan (each, a “Founder Grant” and, together, the “Founder Grants”) pursuant to the terms and conditions of the Business Combination Agreement. One-quarter of each of the Founder Grants was intended to vest upon the achievement of the earlier to occur of (i) a price-based milestone or (ii) a performance-based milestone, with a different set of such price and performance-based milestones applying to each quarter of each of the Founder Grants and so long as the achievement occurs within seven years following the closing of the Business Combination.
The Company accounts for the Founder Grants as four separate tranches, with each tranche consisting of two award conditions, a performance award condition and market award condition. Each tranche vests when either the market condition or performance condition is satisfied (only one condition is satisfied). The Company determined the fair value of the performance award by utilizing the trading price on the Closing Date. When the applicable performance milestone is deemed probable of being achieved, the Company will recognize compensation expense for the portion earned to date over the requisite period. For the market award, the Company determined both the fair value and derived service period using a Monte Carlo simulation model on the Closing Date. The Company will recognize compensation expense for the market award on a straight-line basis over the derived service period. If the applicable performance condition is not probable of being achieved, compensation cost for the value of the award incorporating the market condition is recognized, so long as the requisite service is provided. If the performance milestone becomes probable of being achieved, the full fair value of the award will be recognized, and any remaining expense for the market award will be canceled.
One-quarter of each of the Founder Grants, totaling 10,004,612 shares of Class B common stock, vested immediately prior to the Closing Date pursuant to the terms and conditions of the Business Combination Agreement. On April 14, 2022, the vested 5,002,306 shares of Class B common stock of the Company’s former co-CEO were cancelled. On July 13, 2023, following the expiration of 15 months from the separation of the former co-CEO from the Company on April 13, 2022, the former officer’s unvested 15,006,918 shares of Class B common stock for the remaining three tranches were forfeited. The Company then reversed the previously recognized stock-compensation expense of $59.1 million associated with those shares. During the year ended December 31, 2024, the performance milestone for the second tranche of the outstanding Founder Grant, covering 5,002,306 shares of Class B common stock, was achieved. As of March 31, 2025, there were 10,004,612 RSUs outstanding, representing the remaining two tranches of the outstanding Founder Grant.
For the three months ended March 31, 2025 and 2024, the Company recorded $1.9 million and $22.4 million of stock-based compensation expense, respectively, for the remaining tranches of the outstanding Founder Grant in general and administrative expenses in the consolidated condensed statements of operations.
For the three months ended March 31, 2025 and 2024, the Company recorded $16.4 million and $13.0 million of stock-based compensation expense, respectively, related to RSUs (excluding the Founder Grant).
As of March 31, 2025, the total remaining stock-based compensation expense for unvested RSUs (including the remaining Founder Grant) was $153.2 million, which is expected to be recognized over a weighted-average period of 0.9 years.
Issuance of Class A Common Stock
During the three months ended March 31, 2025, the Company issued 1,906,161 shares of Class A common stock pursuant to a shelf registration statement on Form S-3 filed in May 2024 to certain service providers to satisfy $13.6 million of the Company’s outstanding amounts payable to those service providers.
The Company records stock-based compensation expense for stock-based compensation awards based on the fair value on the date of grant. The stock-based compensation expense is recognized ratably over the course of the requisite service period.
The Company has elected to account for forfeitures as they occur and will record stock-based compensation expense assuming all stockholders will complete the requisite service period. If an employee forfeits an award because they fail to complete the requisite service period, the Company will reverse stock-based compensation expense previously recognized in the period the award is forfeited.
The following table presents stock-based compensation expense included in each respective expense category in the consolidated condensed statements of operations (in millions):
Three Months Ended March 31,
20252024
Research and development$11.1 $12.4 
General and administrative19.0 28.3 
Total stock-based compensation expense$30.1 $40.7 
Warrants
A summary of the Company’s warrant activity is as follows:
Number of
Shares
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Life (Years)
Aggregate
Intrinsic
Value
(In millions)
Outstanding as of January 1, 202520,753,630 $0.01 3.5$202.1 
Outstanding as of March 31, 2025
20,753,630 $0.01 3.2$147.4 
Vested and exercisable as of March 31, 2025
12,805,276 $0.01 2.4$90.9 
United Airlines
On January 29, 2021, the Company entered into a Purchase Agreement (the “United Purchase Agreement”), Collaboration Agreement (the “United Collaboration Agreement”), and Warrant to Purchase Shares Agreement (the “United Warrant Agreement”) with United. Under the terms of the United Purchase Agreement, United has a conditional purchase order for up to 200 of the Company’s aircraft, with an option to purchase an additional 100 aircraft. Those purchases are conditioned upon the Company meeting certain conditions that include, but are not limited to, the certification of the Company’s aircraft by the Federal Aviation Administration (“FAA”) and further negotiation and reaching of mutual agreement on certain material terms related to the purchases. The Company issued 14,741,764 warrants to United to purchase shares of the Company’s Class A common stock. Each warrant provides United with the right to purchase one share of the Company’s Class A common stock at an exercise price of $0.01 per share. The warrants were initially expected to vest in four installments in accordance with the following milestones: the execution of the United Purchase Agreement and the United Collaboration Agreement, the completion of the Business Combination, the certification of the aircraft by the FAA, and the sale of aircraft to United.
On August 9, 2022, the Company entered into Amendment No. 1 to the United Purchase Agreement (the “Amended United Purchase Agreement”) and Amendment No. 1 to the United Warrant Agreement (the “Amended United Warrant Agreement”). In association with the Amended United Purchase Agreement, the Company received a $10.0 million pre-delivery payment from United for 100 of the Company’s aircraft (the “Pre-Delivery Payment”), which was recognized as a contract liability in other long-term liabilities in the Company’s consolidated condensed balance sheets. Pursuant to the Amended United Warrant Agreement, the vesting condition of the fourth milestone of the United Warrant Agreement was modified, and the warrants now vest in four installments in accordance with the following sub-milestones: (i) 737,088 warrants vested upon receipt by the Company of the Pre-Delivery Payment on August 9, 2022; (ii) 2,211,264 warrants vested on February 9, 2023 upon the six-month anniversary of the amendment date; (iii) 3,685.45 warrants shall vest upon the acceptance and delivery of each of the Company’s 160 aircraft; and (iv) 22,112.65 warrants shall vest upon the acceptance and delivery of each of the Company’s 40 aircraft.
The Company accounts for the Amended United Purchase Agreement and the United Collaboration Agreement under ASC 606, Revenue from Contracts with Customers. The Company identified the sale of each aircraft ordered by United as a separate performance obligation in the contract. As the performance obligations have not been satisfied, the Company has not recognized any revenue as of March 31, 2025.
With respect to the warrant vesting milestones outlined above, the Company accounts for them as consideration payable to a customer under ASC 606 related to the future purchase of aircraft by United. The Company determined that the warrants are classified as equity awards based on the criteria of ASC 480, Distinguishing Liabilities from Equity and ASC 718, Compensation — Stock Compensation. Pursuant to ASC 718, the Company measured the grant date fair value of the warrants to be recognized upon the achievement of each of the original four milestones and the vesting of the related warrants, which was
determined to be $13.35, based on a valuation of the Company’s Class A common stock on January 29, 2021.
For the first milestone, issuance of the warrants in conjunction with the execution of the United Purchase Agreement and the United Collaboration Agreement, the Company recorded the grant date fair value of the respective warrant tranche at the vesting date upon satisfaction of the milestone, and the related costs were recorded in other warrant expense due to the absence of historical or probable future revenue. For the second milestone, the completion of the Business Combination transaction, the related costs were also recorded in other warrant expense due to the absence of historical or probable future revenue. A total of 8,845,058 warrants vested from achievement of the first two milestones and were exercised. For the third milestone, the certification of the aircraft by the FAA, the Company will assess whether it is probable that the award will vest at the end of every reporting period. If and when the award is deemed probable of vesting, the Company will begin capitalizing the grant date fair value of the associated warrants as an asset through the vesting date and subsequently amortize the asset as a reduction to revenue as it sells the new aircraft to United.
For the original fourth milestone, the sale of aircraft to United, the Company was initially expected to record the cost associated with the vesting of each portion of warrants within this milestone as a reduction of the transaction price as revenue is recognized for each sale of the aircraft. In connection with the Amended United Warrant Agreement, the Company evaluated the accounting implications associated with the amendment to the fourth milestone in accordance with ASC 606 and ASC 718. For the first sub-milestone, the receipt of the Pre-Delivery Payment, the Company accounted for it as a modification under ASC 718 and recorded the modification date fair value of the associated warrants in other warrant expense upon satisfaction of the sub-milestone on August 9, 2022. For the second sub-milestone, the vesting of warrants on February 9, 2023, the Company accounted for it as a modification under ASC 718 and recorded the modification date fair value of the associated warrants in other warrant expense on a straight-line basis over six months following the amendment date. The modification date fair value of each warrant associated with the first and second sub-milestones was determined to be $4.37, which was the closing price of the Company’s Class A common stock on the modification date. A total of 2,948,352 warrants vested from achievement of the first two sub-milestones under the fourth milestone and were exercised. For the third and fourth sub-milestones, the sale of 160 aircraft and 40 aircraft, respectively, the Company determined that the amendment does not represent a modification under ASC 718. The Company will record the cost associated with the vesting of each portion of the associated warrants as a reduction of the transaction price based on the original grant date fair value as revenue is recognized for each sale of the aircraft.
There was no other warrant expense recognized for the three months ended March 31, 2025 and 2024.
Stellantis N.V.
On January 3, 2023, the Company entered into a manufacturing and collaboration agreement with Stellantis, pursuant to which the Company and Stellantis will collaborate on the development and implementation of the Company’s manufacturing operations for the production of its eVTOL aircraft products (the “Stellantis Collaboration Agreement”). In connection with the Stellantis Collaboration Agreement, the Company entered into a forward purchase agreement (as amended, the “Stellantis Forward Purchase Agreement”) and a warrant agreement (the “Stellantis Warrant Agreement”) with Stellantis on January 3, 2023.
Under the terms of the Stellantis Forward Purchase Agreement, the Company agreed to issue and sell to Stellantis up to $150.0 million of shares of the Company’s Class A common stock pursuant to terms and conditions of the Stellantis Forward Purchase Agreement. The shares pursuant to the Stellantis Forward Purchase Agreement were fully issued in July 2024.
Under the terms of the Stellantis Warrant Agreement, Stellantis is entitled to purchase up to 15.0 million shares of the Company’s Class A common stock, at an exercise price of $0.01 per share (the “Stellantis Warrant”). The Stellantis Warrant will vest and become exercisable in three equal tranches upon 12, 24 and 36 months of the grant date, provided that (i) Stellantis has performed certain undertakings set forth in the Stellantis Collaboration Agreement and/or (ii) the VWAP (as defined in the Stellantis Warrant Agreement) for the Class A common stock exceeding certain specified amounts. Pursuant to the terms and conditions of the Stellantis Collaboration Agreement, Stellantis is deemed to have performed the undertakings if the Stellantis Collaboration Agreement has not been terminated by the Company as of the specified vesting date for each tranche.
As the Company is currently in pre-revenue stage and is not generating any revenue from the Stellantis Collaboration Agreement, all costs incurred with third parties are recorded based on the nature of the costs incurred. The Company accounts for the warrant in accordance with the provisions of ASC 718. The grant date fair value of each warrant was determined to be $1.93, which was the closing price of the Company’s Class A common stock on January 3, 2023. For each tranche of the warrant, the Company will recognize compensation costs as the related services are received from Stellantis on a straight-line basis over the associated service period. During the three months ended March 31, 2025 and 2024, the Company recorded $0.8 million and $2.1 million of research and development expense, respectively, in the consolidated condensed statements of operations in connection with the Stellantis Collaboration Agreement.
v3.25.1
Income Taxes
 3 Months Ended
Mar. 31, 2025
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
The Company recognized foreign current income tax provision of $0.1 million and $0.2 million during the three months ended March 31, 2025 and 2024. The Company did not record any deferred income tax provision for the three months ended March 31, 2025 and 2024. For the three months ended March 31, 2025 and 2024, the provision for income taxes differed from the United States federal statutory rate primarily due to foreign taxes currently payable. The Company realized no benefit for the current year losses due to a full valuation allowance against the United States and foreign net deferred tax assets.
In assessing the realizability of deferred tax assets, management considers whether it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the period in which those temporary differences become deductible. Based upon the analysis of federal and state deferred tax balances, future tax projections, and the Company’s lack of taxable income in the carryback period, the Company did not believe it is more-likely-than-not that the net deferred tax assets will be realizable. Accordingly, the Company had provided a full valuation allowance against the entire domestic and the majority of the foreign net deferred tax assets as of March 31, 2025 and December 31, 2024. The Company intends to maintain the full valuation allowance against the United States net deferred tax assets until sufficient positive evidence exists to support a reversal of, or decrease in, the valuation allowance.
v3.25.1
Liability Classified Warrants
 3 Months Ended
Mar. 31, 2025
Warrants and Rights Note Disclosure [Abstract]  
Liability Classified Warrants Liability Classified Warrants
As of March 31, 2025, there were 17,395,947 public warrants outstanding. Public warrants may only be exercised for a whole number of shares. No fractional shares are issued upon exercise of the public warrants. The public warrants became exercisable on October 30, 2021, 12 months after the closing of the initial public offering of Atlas, the predecessor of Archer. The public warrants will expire five years from the consummation of the Business Combination or earlier upon redemption or liquidation.
Once the public warrants become exercisable, the Company may redeem the public warrants for redemption:
• in whole and not in part;
• at a price of $0.01 per public warrant;
• upon not less than 30 days’ prior written notice of redemption to each warrant holder; and
• if, and only if, the closing price of the Class A common stock equals or exceeds $18.00 per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading days within a 30-trading day period commencing after the warrants become exercisable and ending three business days before the Company sends the notice of redemption to the warrant holders.
If and when the warrants become redeemable by the Company, the Company may exercise its redemption right even if the Company is unable to register or qualify the underlying securities for sale under all applicable state securities laws.
Each public warrant entitles the registered holder to purchase one share of Class A common stock at a price of $11.50 per share. The exercise price and number of Class A common stock issuable upon exercise of the public warrants may be adjusted in certain circumstances including in the event of a share dividend, extraordinary dividend or recapitalization, reorganization, merger, or consolidation. The public warrants will not be adjusted for issuances of Class A common stock at a price below its exercise price. Additionally, in no event will the Company be required to net cash settle the public warrants.
As of March 31, 2025, there were 8,000,000 private placement warrants outstanding. The private placement warrants are identical to the public warrants underlying the shares sold in the initial public offering of Atlas, except that the private placement warrants and the shares of Class A common stock issuable upon the exercise of the private placement warrants became transferable, assignable, and salable on October 16, 2021, 30 days after the completion of the Business Combination, subject to certain limited exceptions. Additionally, the private placement warrants will be exercisable on a cashless basis and will be non-redeemable so long as they are held by the initial purchasers or their permitted transferees. If the private placement warrants are held by someone other than the initial purchasers or their permitted transferees, the private placement warrants will be redeemable by the Company and exercisable by such holders on the same basis as the public warrants.
v3.25.1
Pay vs Performance Disclosure - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Pay vs Performance Disclosure    
Net loss $ (93.4) $ (116.5)
v3.25.1
Insider Trading Arrangements
shares in Thousands
 3 Months Ended
Mar. 31, 2025
shares
Trading Arrangements, by Individual  
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
Eric Lentell [Member]  
Trading Arrangements, by Individual  
Material Terms of Trading Arrangement
On March 31, 2025, Eric Lentell, General Counsel of the Company, adopted a trading arrangement for the sale of the Company’s Class A common stock. The trading arrangement, which expires on December 31, 2025, provides for the potential sale of approximately 100,000 shares of Class A common stock following the vesting and settlement of certain equity awards pursuant to the terms of the plan. Because the actual number of shares to be sold under this trading plan will be net of the shares sold to satisfy Mr. Lentell’s tax obligations, the precise number of shares that may be sold is not yet determinable.
Name Eric Lentell
Title General Counsel
Rule 10b5-1 Arrangement Adopted true
Adoption Date March 31, 2025
Expiration Date December 31, 2025
Arrangement Duration 275 days
Aggregate Available 100
v3.25.1
Summary of Significant Accounting Policies (Policies)
 3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation
The accompanying unaudited consolidated condensed financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial information. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States (“U.S. GAAP”) for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring adjustments, necessary for a fair statement of financial position, results of operations, and cash flows for the interim periods presented have been reflected herein. The results of operations for interim periods are not necessarily indicative of the results to be expected for the full year. The unaudited consolidated condensed financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of and for the fiscal year ended December 31, 2024 set forth in the Company’s Annual Report on Form 10-K filed with the SEC on February 27, 2025. The December 31, 2024 consolidated condensed balance sheet was derived from audited financial statements but does not include all disclosures required by U.S. GAAP.
Cash, Cash Equivalents, and Restricted Cash Cash consists of cash on deposit with financial institutions. Cash equivalents consist of short-term, highly liquid financial instruments that are readily convertible to cash and have maturities of three months or less from the date of purchase.
Cash and Cash Equivalents Restricted cash consists primarily of cash held as security for the Company’s standby letters of credit.
Fair Value Measurements
Fair Value Measurements
The Company applies the provisions of Accounting Standards Codification (“ASC”) 820, Fair Value Measurement, which defines a single authoritative definition of fair value, sets out a framework for measuring fair value, and expands on required disclosures about fair value measurements. The provisions of ASC 820 relate to financial assets and liabilities as well as other assets and liabilities carried at fair value on a recurring and nonrecurring basis. The standard clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the standard establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows:
Level 1Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.
Level 2Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability.
Level 3Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at the measurement date.
The carrying amounts of the Company’s cash, prepaid expenses, other current assets, accounts payable, accrued compensation, and accrued liabilities approximate their fair values due to the short-term nature of these instruments.
Cash Equivalents
The Company’s cash equivalents consist of short-term, highly liquid financial instruments that are readily convertible to cash and have maturities of three months or less from the date of purchase. The Company classifies its money market funds as Level 1, because they are valued based on quoted market prices in active markets.
Public Warrants
The measurement of the public warrants as of March 31, 2025 is classified as Level 1 due to the use of an observable market quote in an active market under the ticker “ACHR WS”.
Private Placement Warrants
The Company utilizes a Monte Carlo simulation model for the private placement warrants at each reporting period, with changes in fair value recognized in the consolidated condensed statements of operations. The estimated fair value of the private placement warrant liability is determined using Level 3 inputs. Inherent in a Monte Carlo simulation model are assumptions related to expected share-price volatility, expected life, risk-free interest rate, and dividend yield.
Financial Instruments Not Recorded at Fair Value on a Recurring Basis
Certain financial instruments, including debt, are not measured at fair value on a recurring basis in the consolidated condensed balance sheets. The fair value of debt as of March 31, 2025 approximates its carrying value (Level 2). Refer to Note 6 - Notes Payable for additional information.
Assets and Liabilities Recorded at Fair Value on a Non-Recurring Basis
Certain assets and liabilities are subject to measurement at fair value on a non-recurring basis if there are indicators of impairment or if they are deemed to be impaired as a result of an impairment review.
Intangible Assets, Net
Intangible Assets, Net
Intangible assets consist solely of domain names and are recorded at cost, net of accumulated amortization, and if applicable, impairment charges. Amortization of domain names is provided over a 15-year estimated useful life on a straight-line basis or based on the pattern in which economic benefits are consumed, if reliably determinable. The Company reviews intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company has analyzed a variety of factors to determine if any circumstance could trigger an impairment loss, and, at this time and based on the information presently known, no event has occurred and indicated that it is more likely than not that an impairment loss has been incurred. Therefore, the Company did not record any impairment charges for its intangible assets for the three months ended March 31, 2025 and 2024.
Cloud Computing Arrangements
Cloud Computing Arrangements
The Company capitalizes certain implementation costs incurred in the application development stage of projects related to its cloud computing arrangements that are service contracts. Capitalized implementation costs are recognized in other long-term assets in the consolidated condensed balance sheets and amortized on a straight-line basis over the fixed, noncancellable term of the associated hosting arrangement plus any reasonably certain renewal periods. Costs related to preliminary project activities and post-implementation activities are expensed as incurred.
Contract Liabilities
Contract Liabilities
The Company records contract liabilities related to differences between the timing of cash receipts from the customer and the recognition of revenue. Contract liabilities consisted of the following (in millions):
March 31,
2025		December 31,
2024
Current portion of contract liabilities
$0.9 $0.9 
Contract liabilities, net of current portion13.3 11.8 
Total
$14.2 $12.7 
Current portion of contract liabilities is recorded in accrued expenses and other current liabilities and contract liabilities, net of current portion is recorded in other long-term liabilities in the Company’s consolidated condensed balance sheets. As of March 31, 2025 and December 31, 2024, the Company’s contract liabilities primarily consisted of a $10.0 million pre-delivery payment received from United Airlines, Inc. (“United”) under the terms of the Amended United Purchase Agreement (defined below) (see Note 9 - Stock-Based Compensation), and installment payments received under a contract order with the United States Air Force for the design, development, and ground test of the Company’s production aircraft, Midnight, of $3.3 million and $1.8 million, respectively. No revenues were recognized during the three months ended March 31, 2025 and 2024.
Net Loss Per Share
Net Loss Per Share
Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding. For all periods presented, the calculation of basic net loss per share excludes shares issued upon the early exercise of stock options where the vesting conditions have not been satisfied. Common stock purchased pursuant to an early exercise of stock options is not deemed to be outstanding for accounting purposes until those shares vest. The Company also excludes unvested shares subject to repurchase in the number of shares outstanding in the consolidated condensed balance sheets and statements of stockholders’ equity.
Because the Company reported net losses for all periods presented, diluted loss per share is the same as basic loss per share.
Contingently issuable shares, including equity awards with performance conditions, are considered outstanding common shares and included in the computation of basic net loss per share as of the date that all necessary conditions to earn the awards have been satisfied.
Comprehensive Loss
Comprehensive Loss
Comprehensive loss includes all changes in equity during the period from non-owner sources. The Company’s comprehensive loss consists of its net loss and foreign currency translation adjustment.
Recent Accounting Pronouncements
Recent Accounting Pronouncements
Recently Issued Accounting Pronouncements Not Yet Adopted
In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires disclosure of incremental income tax information related to the income tax rate reconciliation and expanded disclosures of income taxes paid, among other disclosure requirements. The update is effective for annual periods beginning after December 15, 2024 on a prospective basis, and retrospective application is permitted. The Company is currently evaluating the impact of ASU 2023-09 on its disclosures within its consolidated financial statements.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which requires disclosure of additional information about specific expense categories in the notes to the financial statements. The update is effective for annual periods beginning after December 15, 2026, and interim periods within annual periods beginning after December 15, 2027. Early adoption is permitted. The update can be applied either (1) prospectively to financial statements issued for reporting periods after the effective date or (2) retrospectively to any of all prior periods presented in the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its disclosures within its consolidated financial statements.
v3.25.1
Summary of Significant Accounting Policies (Tables)
 3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]  
Schedule of Cash and Cash Equivalents
The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported in the consolidated condensed balance sheets that sum to amounts reported on the consolidated condensed statements of cash flows (in millions):
March 31,
2025		December 31,
2024
Cash and cash equivalents$1,030.4 $834.5 
Restricted cash6.5 6.8 
Total cash, cash equivalents, and restricted cash$1,036.9 $841.3 
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis
The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2025 and December 31, 2024 and indicate the fair value hierarchy of the valuation inputs the Company utilized to determine such fair value (in millions):
As of March 31, 2025
DescriptionLevel 1Level 2Level 3Total
Assets:
Cash equivalents:
Money market funds$906.0 $— $— $906.0 
Liabilities:
Warrant liability – public warrants$31.3 $— $— $31.3 
Warrant liability – private placement warrants$— $— $16.4 $16.4 
As of December 31, 2024
DescriptionLevel 1Level 2Level 3Total
Assets:
Cash equivalents:
Money market funds$729.9 $— $— $729.9 
Liabilities:
Warrant liability – public warrants$56.0 $— $— $56.0 
Warrant liability – private placement warrants$— $— $33.4 $33.4 
Schedule of Cash Equivalents and Short-Term Investments
The following table presents a summary of the Company’s cash equivalents as of March 31, 2025 and December 31, 2024 (in millions):
As of March 31, 2025
DescriptionAmortized CostUnrealized GainsUnrealized LossesFair Value
Cash equivalents:
Money market funds$906.0 $— $— $906.0 
Total$906.0 $— $— $906.0 
As of December 31, 2024
DescriptionAmortized CostUnrealized GainsUnrealized LossesFair Value
Cash equivalents:
Money market funds$729.9 $— $— $729.9 
Total$729.9 $— $— $729.9 
Schedule of Key Inputs into the Monte Carlo Simulation Model for the Private Placement Warrants
The key inputs into the Monte Carlo simulation model for the private placement warrants are as follows:
InputMarch 31,
2025		December 31,
2024
Stock price$7.11 $9.75 
Strike price$11.50 $11.50 
Term (in years)1.51.7
Risk-free rate3.9 %4.2 %
Volatility88.9 %92.1 %
Dividend yield0.0 %0.0 %
Schedule of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
The following table presents the change in fair value of the Company’s Level 3 private placement warrants during the three months ended March 31, 2025 (in millions):

Balance as of December 31, 2024
$33.4 
Change in fair value(17.0)
Balance as of March 31, 2025
$16.4 
Schedule of Contract Liabilities Contract liabilities consisted of the following (in millions):
March 31,
2025		December 31,
2024
Current portion of contract liabilities
$0.9 $0.9 
Contract liabilities, net of current portion13.3 11.8 
Total
$14.2 $12.7 
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share
The following table presents the number of antidilutive shares excluded from the calculation of diluted net loss per share:
Three Months Ended March 31,
20252024
Options to purchase common stock1,871,637 2,915,738 
Unvested restricted stock units31,685,118 35,015,943 
Warrants33,344,301 47,011,560 
Shares issuable under the Employee Stock Purchase Plan (Note 9)
688,280 1,091,452 
Total67,589,336 86,034,693 
Schedule of Financial Information Respect to the Company’s Single Operating Segment
The following table presents significant expenses provided to the Chief Operating Decision Maker (in millions):
Three Months Ended March 31,
20252024
Operating expenses
Depreciation and amortization expense
$4.1 $2.3 
Research and development warrant expense
0.8 2.1 
Stock-based compensation
30.1 40.7 
Technology and dispute resolution agreements expense
— 10.3 
Other research and development expense
88.2 67.1 
Other general and administrative expense
20.8 19.7 
Total operating expenses144.0 142.2 
Loss from operations(144.0)(142.2)
Other income, net42.0 20.6 
Interest income, net8.7 5.3 
Loss before income taxes(93.3)(116.3)
Income tax expense(0.1)(0.2)
Net loss$(93.4)$(116.5)
v3.25.1
Property and Equipment, Net (Tables)
 3 Months Ended
Mar. 31, 2025
Property, Plant and Equipment [Abstract]  
Schedule of Property, Plant and Equipment Net
Property and equipment, net, consisted of the following (in millions):
March 31,
2025		December 31,
2024
Building$67.3 $64.4 
Furniture, fixtures, and equipment29.3 24.7 
Vehicles0.9 0.1 
Computer hardware6.0 5.8 
Computer software2.0 1.9 
Website design0.8 0.8 
Building and leasehold improvements36.9 34.2 
Construction in progress11.0 13.3 
Total property and equipment154.2 145.2 
Less: Accumulated depreciation(22.1)(18.4)
Total property and equipment, net$132.1 $126.8 
The following table presents depreciation expense included in each respective expense category in the consolidated condensed statements of operations (in millions):
Three Months Ended March 31,
20252024
Research and development$3.6 $2.0 
General and administrative0.1 0.1 
Total depreciation expense$3.7 $2.1 
v3.25.1
Accrued Expenses and Other Current Liabilities (Tables)
 3 Months Ended
Mar. 31, 2025
Other Liabilities Disclosure [Abstract]  
Schedule of Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following (in millions):
March 31,
2025		December 31,
2024
Accrued professional fees$10.8 $6.5 
Accrued employee costs11.2 22.2 
Accrued parts and materials15.9 12.5 
Current portion of contract liabilities0.9 0.9 
Other current liabilities9.8 10.7 
Total$48.6 $52.8 
v3.25.1
Notes Payable (Tables)
 3 Months Ended
Mar. 31, 2025
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
Notes payable consisted of the following (in millions):
March 31,
2025		December 31,
2024
Synovus Bank Loan$65.0 $65.0 
Loan unamortized discount and loan issuance costs(0.9)(1.0)
Total debt, net of discount and loan issuance costs64.1 64.0 
Less current portion, net of discount and loan issuance costs— — 
Total long-term notes payable, net of discount and loan issuance costs$64.1 $64.0 
Schedule of Maturities of Long-term Debt
The future scheduled principal maturities of the Loan as of March 31, 2025 are as follows (in millions):

Remaining 2025
$— 
2026
0.4 
2027
2.6 
2028
2.6 
2029
2.6 
Thereafter56.8 
$65.0 
v3.25.1
Commitments and Contingencies (Tables)
 3 Months Ended
Mar. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Schedule of Lease Costs
The Company’s lease costs were as follows (in millions):
Three Months Ended March 31,
20252024
Operating lease cost$1.3 $1.2 
Short-term lease cost0.1 0.1 
Total lease cost$1.4 $1.3 
The Company’s weighted-average remaining lease term and discount rate as of March 31, 2025 and 2024 were as follows:
20252024
Weighted-average remaining lease term (in months)4653
Weighted-average discount rate14.4 %14.6 %
Supplemental cash flow information and non-cash activities related to right-of-use assets and lease liabilities were as follows (in millions):
Three Months Ended March 31,
20252024
Operating cash outflows from operating leases$1.5 $1.1 
Operating lease liabilities from obtaining right-of-use assets$0.2 $0.3 
Schedule of Operating Lease Maturities
The minimum aggregate future obligations under the Company’s non-cancelable operating leases as of March 31, 2025 were as follows (in millions):
Remaining 2025
$4.7 
20265.5 
20272.9 
20282.2 
20292.3 
Thereafter2.1 
Total future lease payments19.7 
Less: leasehold improvement allowance(0.5)
Total net future lease payments19.2 
Less: imputed interest(5.0)
Present value of future lease payments$14.2 
v3.25.1
Stock-Based Compensation​ (Tables)
 3 Months Ended
Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions The following table sets forth the key assumptions and fair value results for each award granted in the Company’s six-month offering period that started on December 1, 2024:
December 1, 2024
Stock price$9.57 
Term (in years)0.5
Risk-free interest rate4.4 %
Volatility85.0 %
Dividend yield0.0 %
Grant date fair value per share$3.67 
Schedule of Stock Option Activity
A summary of the Company’s stock option activity is as follows:
Number of
Shares
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Life (Years)
Aggregate
Intrinsic
Value
(In millions)
Outstanding as of January 1, 20252,118,011 $0.13 5.8$20.4 
Exercised(168,509)$0.10 $1.5 
Expired/forfeited(77,865)$0.15 
Outstanding as of March 31, 2025
1,871,637 $0.14 5.6$13.1 
Exercisable as of March 31, 2025
1,494,201 $0.13 5.5$10.4 
Vested and expected to vest as of March 31, 2025
1,871,637 $0.14 5.6$13.1 
Schedule of Share-based Payment Arrangement, Restricted Stock Unit, Activity
A summary of the Company’s RSU activity is as follows:
Number of
Shares
Weighted
Average
Grant Fair Value
Outstanding as of January 1, 202528,658,246 $5.02 
Granted7,906,872 $9.51 
Performance based adjustment (1)
190,844 $6.39 
Vested(4,578,181)$6.30 
Forfeited(492,663)$5.49 
Outstanding as of March 31, 2025
31,685,118 $5.96 
(1) Represents units adjusted for the vesting of the first tranche of PSUs (defined below) granted in 2024.
Schedule of Share-Based Payment Award, Valuation Assumptions
The following assumptions were used to estimate the fair value, using the Monte Carlo simulation, of the PSUs:
February 17, 2025
Stock price$10.35 
Term (in years)3.0
Risk-free interest rate4.2 %
Volatility88.2 %
Dividend yield0.0 %
Schedule of Share-based Payment Arrangement, Expensed and Capitalized, Amount
The following table presents stock-based compensation expense included in each respective expense category in the consolidated condensed statements of operations (in millions):
Three Months Ended March 31,
20252024
Research and development$11.1 $12.4 
General and administrative19.0 28.3 
Total stock-based compensation expense$30.1 $40.7 
Schedule of Share-based Payment Arrangement, Warrant Activity
A summary of the Company’s warrant activity is as follows:
Number of
Shares
Weighted
Average
Exercise
Price
Weighted
Average
Remaining
Contractual
Life (Years)
Aggregate
Intrinsic
Value
(In millions)
Outstanding as of January 1, 202520,753,630 $0.01 3.5$202.1 
Outstanding as of March 31, 2025
20,753,630 $0.01 3.2$147.4 
Vested and exercisable as of March 31, 2025
12,805,276 $0.01 2.4$90.9 
v3.25.1
Liquidity and Going Concern (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Accumulated deficit $ (1,779.0) $ (1,685.6)
Cash and cash equivalents $ 1,030.4 $ 834.5
v3.25.1
Summary of Significant Accounting Policies - Narrative (Details)
 3 Months Ended
Mar. 31, 2025
USD ($)
$ / shares
Mar. 31, 2024
USD ($)
Dec. 31, 2024
USD ($)
$ / shares
Aug. 09, 2022
USD ($)
Cash and Cash Equivalents [Line Items]        
Cash and cash equivalents $ 1,030,400,000   $ 834,500,000  
Change in fair value of warrant liabilities $ 41,700,000 $ 20,800,000    
Finite-lived intangible asset, useful life 15 years      
Intangible assets, net $ 300,000   300,000  
Capitalized cloud computing implementation costs 6,300,000   5,900,000  
Contract with liability, revenue recognized 0 0    
United Airlines Inc.        
Cash and Cash Equivalents [Line Items]        
Purchase agreement, pre delivery payment received 10,000,000   10,000,000 $ 10,000,000
United States Air Force        
Cash and Cash Equivalents [Line Items]        
Purchase agreement, installment payment received $ 3,300,000   $ 1,800,000  
Stock price        
Cash and Cash Equivalents [Line Items]        
Warrant liability, measurement input (in dollars per share) | $ / shares 7.11   9.75  
Public Warrants | Stock price        
Cash and Cash Equivalents [Line Items]        
Warrant liability, measurement input (in dollars per share) | $ / shares 1.80   3.22  
Private Placement Warrants        
Cash and Cash Equivalents [Line Items]        
Change in fair value of warrant liabilities $ 17,000,000 $ 7,900,000    
Money market funds        
Cash and Cash Equivalents [Line Items]        
Cash and cash equivalents $ 906,000,000   $ 729,900,000  
v3.25.1
Summary of Significant Accounting Policies - Schedule of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Mar. 31, 2024
Dec. 31, 2023
Accounting Policies [Abstract]        
Cash and cash equivalents $ 1,030.4 $ 834.5    
Restricted cash 6.5 6.8    
Total cash, cash equivalents, and restricted cash $ 1,036.9 $ 841.3 $ 412.5 $ 471.5
v3.25.1
Summary of Significant Accounting Policies - Schedule of Fair Value Recurring Basis (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Recurring | Public Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value $ 31.3 $ 56.0
Recurring | Private Placement Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 16.4 33.4
Level 1 | Recurring | Public Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 31.3 56.0
Level 1 | Recurring | Private Placement Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 0.0 0.0
Level 2 | Recurring | Public Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 0.0 0.0
Level 2 | Recurring | Private Placement Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 0.0 0.0
Level 3 | Recurring | Public Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 0.0 0.0
Level 3 | Recurring | Private Placement Warrants    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant liability, fair value 16.4 33.4
Money market funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents: 906.0 729.9
Money market funds | Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents: 906.0 729.9
Money market funds | Level 1 | Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents: 906.0 729.9
Money market funds | Level 2 | Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents: 0.0 0.0
Money market funds | Level 3 | Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents: $ 0.0 $ 0.0
v3.25.1
Summary of Significant Accounting Policies - Schedule of Cash, Cash Equivalents, and Short-Term Investments (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Debt Securities, Available-for-Sale [Abstract]    
Unrealized Gains $ 0.0 $ 0.0
Unrealized Losses 0.0 0.0
Amortized Cost 906.0 729.9
Fair Value 906.0 729.9
Money market funds    
Cash equivalents:    
Cash equivalents: $ 906.0 $ 729.9
v3.25.1
Summary of Significant Accounting Policies - Schedule of Measurement Input (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2025
$ / shares
Dec. 31, 2024
$ / shares
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrants outstanding, term 1 year 6 months 1 year 8 months 12 days
Stock price    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrant liability, measurement input (in dollars per share) 7.11 9.75
Strike price    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrant liability, measurement input (in dollars per share) 11.50 11.50
Risk-free rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrant liability, measurement input (in dollars per share) 0.039 0.042
Volatility    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrant liability, measurement input (in dollars per share) 0.889 0.921
Dividend yield    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Warrant liability, measurement input (in dollars per share) 0.000 0.000
v3.25.1
Summary of Significant Accounting Policies - Schedule of Private Placement Warrants (Details) - Warrants - Level 3
$ in Millions
 3 Months Ended
Mar. 31, 2025
USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]  
Beginning balance $ 33.4
Change in fair value (17.0)
Ending balance $ 16.4
v3.25.1
Summary of Significant Accounting Policies - Schedule of Contract Liabilities (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Accounting Policies [Abstract]    
Current portion of contract liabilities $ 0.9 $ 0.9
Contract liabilities, net of current portion 13.3 11.8
Total $ 14.2 $ 12.7
v3.25.1
Summary of Significant Accounting Policies - Schedule of Antidilutive Securities (Details) - shares
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation (in shares) 67,589,336 86,034,693
Options to purchase common stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation (in shares) 1,871,637 2,915,738
Unvested restricted stock units    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation (in shares) 31,685,118 35,015,943
Warrants    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation (in shares) 33,344,301 47,011,560
Shares issuable under the Employee Stock Purchase Plan (Note 9)    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Antidilutive securities excluded from computation (in shares) 688,280 1,091,452
v3.25.1
Summary of Significant Accounting Policies - Schedule of Financial Information Respect to the Company’s Single Operating Segment (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Accounting Policies [Abstract]    
Depreciation and amortization expense $ 4.1 $ 2.3
Research and development warrant expense 0.8 2.1
Stock-based compensation 30.1 40.7
Technology and dispute resolution agreements expense 0.0 10.3
Research and development warrant expense 88.2 67.1
Other general and administrative expense 20.8 19.7
Total operating expenses 144.0 142.2
Loss from operations (144.0) (142.2)
Other income, net 42.0 20.6
Interest income, net 8.7 5.3
Loss before income taxes (93.3) (116.3)
Income tax expense (0.1) (0.2)
Net loss $ (93.4) $ (116.5)
v3.25.1
Property and Equipment, Net - Schedule of Useful Life for Property, Plant and Equipment (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 154.2 $ 145.2
Less: Accumulated depreciation (22.1) (18.4)
Total property and equipment, net 132.1 126.8
Building    
Property, Plant and Equipment [Line Items]    
Total property and equipment 67.3 64.4
Furniture, fixtures, and equipment    
Property, Plant and Equipment [Line Items]    
Total property and equipment 29.3 24.7
Vehicles    
Property, Plant and Equipment [Line Items]    
Total property and equipment 0.9 0.1
Computer hardware    
Property, Plant and Equipment [Line Items]    
Total property and equipment 6.0 5.8
Computer software    
Property, Plant and Equipment [Line Items]    
Total property and equipment 2.0 1.9
Website design    
Property, Plant and Equipment [Line Items]    
Total property and equipment 0.8 0.8
Building and leasehold improvements    
Property, Plant and Equipment [Line Items]    
Total property and equipment 36.9 34.2
Construction in progress    
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 11.0 $ 13.3
v3.25.1
Property and Equipment, Net - Schedule of Depreciation Expense (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Depreciation    
Total depreciation expense $ 3.7 $ 2.1
Research and development    
Depreciation    
Total depreciation expense 3.6 2.0
General and administrative    
Depreciation    
Total depreciation expense $ 0.1 $ 0.1
v3.25.1
Accrued Expenses and Other Current Liabilities (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Other Liabilities Disclosure [Abstract]    
Accrued professional fees $ 10.8 $ 6.5
Accrued employee costs 11.2 22.2
Accrued parts and materials 15.9 12.5
Current portion of contract liabilities 0.9 0.9
Other current liabilities 9.8 10.7
Total $ 48.6 $ 52.8
v3.25.1
Notes Payable - Schedule of Long-Term Notes Payable (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Debt Instrument [Line Items]    
Synovus Bank Loan $ 65.0  
Total debt, net of discount and loan issuance costs 64.1 $ 64.0
Less current portion, net of discount and loan issuance costs 0.0 0.0
Total long-term notes payable, net of discount and loan issuance costs 64.1 64.0
Credit Facility | Synovus Bank Loans    
Debt Instrument [Line Items]    
Synovus Bank Loan 65.0 65.0
Loan unamortized discount and loan issuance costs $ (0.9) $ (1.0)
v3.25.1
Notes Payable - Narrative (Details)
 3 Months Ended 12 Months Ended
Oct. 05, 2023
USD ($)
Mar. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Nov. 14, 2026
installment
Nov. 14, 2023
interest
Debt Instrument [Line Items]          
Long-term debt   $ 64,100,000 $ 64,000,000.0    
Synovus Bank Loans | Credit Facility          
Debt Instrument [Line Items]          
Interest expense   1,100,000 300,000    
Carrying value of the loan, net of unamortized issuance costs   $ 900,000 $ 1,000,000.0    
Synovus Bank Loans | Credit Facility | Minimum          
Debt Instrument [Line Items]          
Effective rate (as percent)   6.60% 6.70%    
Synovus Bank Loans | Credit Facility | Maximum          
Debt Instrument [Line Items]          
Effective rate (as percent)   7.10% 7.20%    
Synovus Bank Loans | Secured Debt          
Debt Instrument [Line Items]          
Line of credit, borrowing capacity $ 65,000,000        
Number of monthly interest payment | interest         120
Basis spread on variable rate 2.00%        
Increase in annual interest rate upon event of default (as percent) 5.00%        
Line of credit   $ 65,000,000      
Synovus Bank Loans | Secured Debt | Forecast          
Debt Instrument [Line Items]          
Number of monthly installments | installment       84  
v3.25.1
Notes Payable - Schedule of Principal Maturities of Notes Payable (Details)
$ in Millions
Mar. 31, 2025
USD ($)
Debt Disclosure [Abstract]  
Remaining 2025 $ 0.0
2026 0.4
2027 2.6
2028 2.6
2029 2.6
Thereafter 56.8
Long-term debt $ 65.0
v3.25.1
Commitments and Contingencies - Schedule of Lease Costs (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]    
Operating lease cost $ 1.3 $ 1.2
Short-term lease cost 0.1 0.1
Total lease cost $ 1.4 $ 1.3
Weighted-average remaining lease term (in months) 46 months 53 months
Weighted-average discount rate 14.40% 14.60%
v3.25.1
Commitments and Contingencies - Schedule of Operating Lease Schedule of Maturity (Details)
$ in Millions
Mar. 31, 2025
USD ($)
Commitments and Contingencies Disclosure [Abstract]  
Remaining 2025 $ 4.7
2026 5.5
2027 2.9
2028 2.2
2029 2.3
Thereafter 2.1
Total future lease payments 19.7
Less: leasehold improvement allowance (0.5)
Total net future lease payments 19.2
Less: imputed interest (5.0)
Present value of future lease payments $ 14.2
v3.25.1
Commitments and Contingencies - Schedule of Non-Cash Lease Activities (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]    
Operating cash outflows from operating leases $ 1.5 $ 1.1
Operating lease liabilities from obtaining right-of-use assets $ 0.2 $ 0.3
v3.25.1
Commitments and Contingencies - Narrative (Details)
$ in Millions
May 17, 2024
lawsuit
Mar. 31, 2025
USD ($)
Delaware Class Action Litigation    
Debt Instrument [Line Items]    
Number of putative stockholders lawsuit | lawsuit 2  
Standby Letters of Credit | Line of Credit    
Debt Instrument [Line Items]    
Line of credit | $   $ 5.5
v3.25.1
Preferred and Common Stock (Details)
 1 Months Ended 3 Months Ended
Feb. 12, 2025
USD ($)
shares
Jan. 06, 2025
USD ($)
Dec. 11, 2024
USD ($)
$ / shares
shares
Aug. 08, 2024
USD ($)
$ / shares
shares
Nov. 30, 2024
USD ($)
Mar. 31, 2025
USD ($)
vote
shares
Mar. 31, 2024
shares
Dec. 31, 2024
shares
Class of Stock [Line Items]                
Preferred stock, outstanding (in shares) | shares           0   0
Dividends declared | $           $ 0    
PIPE Financing | Private Placement                
Class of Stock [Line Items]                
Price per share (in dollars per share) | $ / shares     $ 6.65 $ 3.35        
Number of shares issued in transaction (in shares) | shares     63,909,776 49,283,582        
Consideration received on transaction | $     $ 407,700,000 $ 158,000,000        
Stellantis PIPE Financing | Private Placement                
Class of Stock [Line Items]                
Number of shares issued in transaction (in shares) | shares     751,879 2,982,089        
Consideration received on transaction | $   $ 9,600,000 $ 5,000,000          
Class A                
Class of Stock [Line Items]                
Voting rights, votes per share | vote           1    
Class A | Common Stock                
Class of Stock [Line Items]                
Number of shares issued in transaction (in shares) | shares             6,569,896  
Class A | Third At-The-Market Program | Common Stock                
Class of Stock [Line Items]                
Number of shares issued in transaction (in shares) | shares           0    
Remaining amount | $           $ 47,500,000    
Class A | Third At-The-Market Program | Maximum | Common Stock                
Class of Stock [Line Items]                
Consideration received on transaction | $         $ 70,000,000      
Class A | At-The-Market Program | Common Stock                
Class of Stock [Line Items]                
Commission fee, percentage         3.00%      
Class A | Registered Direct Offering                
Class of Stock [Line Items]                
Number of shares issued in transaction (in shares) | shares 35,500,000              
Proceeds from issuance of common stock | $ $ 289,500,000              
v3.25.1
Stock-Based Compensation​ - Amended and Restated 2021 Plan (Details) - 2021 Stock Plan - Class A - shares
 1 Months Ended
Jun. 30, 2022
Jan. 01, 2025
Jun. 10, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Capital shares reserved for future issuance (in shares)   25,191,478 34,175,708
Percentage of outstanding stock maximum 5.00%    
v3.25.1
Stock-Based Compensation​ - Employee Stock Purchase Plan (Details) - USD ($)
$ in Millions
 1 Months Ended 3 Months Ended
Jan. 01, 2025
Aug. 31, 2021
Mar. 31, 2025
Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total stock-based compensation expense     $ 30.1 $ 40.7
Class A        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Percent of employees gross pay   15.00%    
2021 Employee Stock Purchase Plan | Class A        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of additional shares authorized (in shares) 4,677,185      
Maximum number of shares authorized for issuance (in shares)     15,762,995  
Number of shares remained available (in shares)     12,810,367  
Employee Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Purchase price of common stock, percent   85.00%    
Percentage of outstanding stock maximum   1.00%    
Number of additional shares issuable (in shares)   9,938,118    
Offering period   6 months 6 months  
Offering period occurrence   6 months    
Total stock-based compensation expense     $ 0.9 $ 0.7
Unvested stock options     $ 0.6  
v3.25.1
Stock-Based Compensation​ - Schedule of Share-Based Payment Award, Valuation Assumptions (Details) - $ / shares
Feb. 17, 2025
Dec. 01, 2024
Employee Stock    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock price (in dollars per share)   $ 9.57
Term (in years)   6 months
Risk-free interest rate   4.40%
Volatility   85.00%
Dividend yield   0.00%
Grant date fair value per share (in dollars per share)   $ 3.67
Performance Stock Units    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock price (in dollars per share) $ 10.35  
Term (in years) 3 years  
Risk-free interest rate 4.20%  
Volatility 88.20%  
Dividend yield 0.00%  
v3.25.1
Stock-Based Compensation​ - Annual Equity Awards and Stock Options (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense $ 30.1 $ 40.7
Options to purchase common stock    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense 0.6 0.8
Unvested stock options $ 1.6  
Weighted-average period 3 months 18 days  
Annual Equity Awards    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense $ 3.8 $ 3.8
v3.25.1
Stock-Based Compensation​ - Schedule of Stock Option Activity (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2025
Dec. 31, 2024
Number of Shares    
Beginning balance (in shares) 2,118,011  
Exercised (in shares) (168,509)  
Expired/forfeited (in shares) (77,865)  
Ending balance (in shares) 1,871,637 2,118,011
Exercisable (in shares) 1,494,201  
Vested and expected to vest (in shares) 1,871,637  
Weighted Average Exercise Price    
Beginning balance (in dollars per share) $ 0.13  
Exercise (in dollars per share) 0.10  
Expired/forfeited (in dollars per share) 0.15  
Ending balance (in dollars per share) 0.14 $ 0.13
Exercisable, Weighted average exercise price per share (in dollars per share) 0.13  
Vested and expected to vest (in dollars per share) $ 0.14  
Employee and Non Employee stock option Additional Disclosures    
Weighted average remaining contractual life (in years) 5 years 7 months 6 days 5 years 9 months 18 days
Exercisable, weighted average remaining contractual term (Years) 5 years 6 months  
Vested and expected, weighted average remaining contractual term (Years) 5 years 7 months 6 days  
Aggregate intrinsic value $ 13.1 $ 20.4
Exercised, aggregate intrinsic value 1.5  
Exercisable as of March 31, 2025 10.4  
Vested and expected, aggregate intrinsic value $ 13.1  
v3.25.1
Stock-Based Compensation​ - Schedule of Restricted Stock Activity (Details) - Restricted Stock Units - $ / shares
 3 Months Ended
Sep. 16, 2021
Mar. 31, 2025
Number of Shares    
Beginning balance (in shares)   28,658,246
Granted (in shares) 20,009,224 7,906,872
Performance based adjustment (in shares)   190,844
Vested (in shares)   (4,578,181)
Forfeited (in shares)   (492,663)
Ending balance (in shares)   31,685,118
Weighted Average Grant Fair Value    
Beginning balance (in dollars per share)   $ 5.02
Granted (in dollars per share)   9.51
Performance based adjustment (in dollars per share)   6.39
Vested (in dollars per share)   6.30
Forfeited (in dollars per share)   5.49
Ending balance (in dollars per share)   $ 5.96
v3.25.1
Stock-Based Compensation​ - Restricted Stock Units (Details)
$ in Millions
 3 Months Ended 12 Months Ended
Jul. 13, 2023
USD ($)
tranche
shares
Apr. 14, 2022
shares
Sep. 16, 2021
tranche
shares
Sep. 15, 2021
shares
Mar. 31, 2025
USD ($)
tranche
shares
Mar. 31, 2024
USD ($)
Dec. 31, 2024
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Total stock-based compensation expense | $         $ 30.1 $ 40.7  
General and administrative              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Total stock-based compensation expense | $         $ 19.0 28.3  
Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Conversion ratio         1    
Unvested restricted stock units              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (in shares)     20,009,224   7,906,872    
Milestone achievement period     7 years        
Founder grants, number of tranches | tranche     4        
Vested and exercisable (in shares)         4,578,181    
Forfeited (in shares)         492,663    
Number of outstanding (in shares)         31,685,118   28,658,246
Total stock-based compensation expense | $         $ 16.4 13.0  
Share-based payment arrangement, nonvested award, cost not yet recognized, amount | $         $ 153.2    
Weighted-average period         10 months 24 days    
Unvested restricted stock units | General and administrative              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Total stock-based compensation expense | $         $ 1.9 $ 22.4  
Unvested restricted stock units | Class B              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting period 15 months            
Vested and exercisable (in shares)       10,004,612      
Forfeited (in shares)   5,002,306         5,002,306
Number of outstanding (in shares) 15,006,918            
Number of tranches forfeited | tranche 3            
Reversal of expense | $ $ 59.1            
Shares outstanding (in shares)         10,004,612    
Unvested restricted stock units | Class B | General and administrative              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of tranches outstanding | tranche         2    
Unvested restricted stock units | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting period         3 years    
Unvested restricted stock units | 2021 Stock Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (in shares)         5,487,006    
Performance Stock Units              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Performance period         3 years    
Quarterly Equity Awards | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Conversion ratio         1    
Quarterly Equity Awards | Unvested restricted stock units | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (in shares)         1,897,941    
If Vesting Conditions Are Not Met | Unvested restricted stock units | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting period         1 year    
Based on Company’s Relative Performance of Total Shareholder Return | Unvested restricted stock units | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (in shares)         521,925    
Award vesting period         3 years    
Based on Company’s Relative Performance of Total Shareholder Return | Performance Stock Units | Amended and Restated 2021 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Conversion ratio         1,000    
Based on Company’s Relative Performance of Total Shareholder Return | Performance Stock Units | Amended and Restated 2021 Plan | Minimum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Payout range percentage         0.00%    
Based on Company’s Relative Performance of Total Shareholder Return | Performance Stock Units | Amended and Restated 2021 Plan | Maximum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Payout range percentage         200.00%    
v3.25.1
Stock-Based Compensation​ - Issuance of Class A Common Stock (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2025
USD ($)
shares
Vendor  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Accounts payable | $ $ 13.6
Class A | Common Stock  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Issuance of preferred stock (in shares) | shares 1,906,161
v3.25.1
Stock-Based Compensation​ - Schedule of Stock-based Compensation Expense Included in Respective Expense Category (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense $ 30.1 $ 40.7
Research and development    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense 11.1 12.4
General and administrative    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation expense $ 19.0 $ 28.3
v3.25.1
Stock-Based Compensation​ - Schedule of Share-based Compensation, Warrant Activity (Details) - Warrants - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2025
Dec. 31, 2024
Number of Shares    
Beginning balance (in shares) 20,753,630  
Ending balance (in shares) 20,753,630 20,753,630
Vested and exercisable (in shares) 12,805,276  
Weighted Average Exercise Price    
Beginning balance (in dollars per share) $ 0.01  
Ending balance (in dollars per share) 0.01 $ 0.01
Vested and exercisable (in dollars per share) $ 0.01  
Weighted Average Remaining Contractual Life (Years)    
Outstanding (in years) 3 years 2 months 12 days 3 years 6 months
Vested and exercisable (in years) 2 years 4 months 24 days  
Aggregate Intrinsic Value (In millions)    
Outstanding at period start $ 202.1  
Outstanding at period end 147.4 $ 202.1
Vested and exercisable $ 90.9  
v3.25.1
Stock-Based Compensation​ - United Airlines (Details)
 3 Months Ended 6 Months Ended 8 Months Ended
Aug. 09, 2022
USD ($)
aircraft
installment
$ / shares
shares
Jan. 29, 2021
milestone
aircraft
installment
$ / shares
shares
Mar. 31, 2025
USD ($)
Mar. 31, 2024
USD ($)
Feb. 09, 2023
shares
Sep. 16, 2021
shares
Dec. 31, 2024
USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of conditional purchased aircraft | aircraft   200          
Option to purchase of additional aircraft | aircraft   100          
Class of warrant or right, vested during the period (in shares)           8,845,058  
Other warrant expense | $     $ 0 $ 0      
United              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Cashless exercise of warrants (in shares)         2,948,352    
Sub Milestone One and Two              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Fair value of each warrant (in dollars per share) | $ / shares $ 4.37            
Class A              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Valuation of common stock, per share (in dollars per share) | $ / shares   $ 13.35          
United Airlines Inc.              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of conditional purchased aircraft | aircraft 100            
Purchase agreement, pre delivery payment received | $ $ 10,000,000   $ 10,000,000       $ 10,000,000
United Airlines Inc. | Warrants for Collaboration Agreement with United Airlines Inc.              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Warrants, issued or issuable (in shares)   14,741,764          
Warrants price per share (in dollars per share) | $ / shares   $ 0.01          
Number of vesting installments | installment 4 4          
Warrants, vesting period 6 months            
Number of vesting milestones | milestone   4          
United Airlines Inc. | Warrants for Collaboration Agreement with United Airlines Inc. | Class A              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of securities called by each warrant or right (in shares)   1          
United Airlines Inc. | Amended United Warrant Agreement | Sub Milestone One              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Warrant vested and expected to vest (in shares) 737,088            
United Airlines Inc. | Amended United Warrant Agreement | Sub Milestone Two              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Warrant vested and expected to vest (in shares) 2,211,264            
United Airlines Inc. | Amended United Warrant Agreement | Sub Milestone Three              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of conditional purchased aircraft | aircraft 160            
Warrant vested and expected to vest (in shares) 3,685.45            
United Airlines Inc. | Amended United Warrant Agreement | Sub Milestone Four              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of conditional purchased aircraft | aircraft 40            
Warrant vested and expected to vest (in shares) 22,112.65            
v3.25.1
Stock-Based Compensation​ - Stellantis N.V. (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
 3 Months Ended
Jan. 03, 2023
Mar. 31, 2025
Mar. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Research and development   $ 103.7 $ 83.5
Stellantis N.V.      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Warrants price per share (in dollars per share) $ 0.01    
Warrants, weighted average grant date fair value (in dollars per share) $ 1.93    
Stellantis N.V. | Warrant Exercisable Period One      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 12 months    
Stellantis N.V. | Warrant Exercisable Period Two      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 24 months    
Stellantis N.V. | Warrant Exercisable Period Three      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 36 months    
Stellantis N.V. | Warrants for Collaboration Agreement with FCA US LLC      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Research and development   $ 0.8 $ 2.1
Stellantis N.V. | Class A      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Sale of stock value $ 150.0    
Number of securities called by warrants or rights (in shares) 15.0    
Share price (in dollars per share) $ 1.93    
v3.25.1
Income Taxes (Details) - USD ($)
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Income Tax Disclosure [Abstract]    
Current foreign tax expense (benefit) $ 100,000 $ 200,000
Deferred income tax provision $ 0 $ 0
v3.25.1
Liability Classified Warrants (Details)
 3 Months Ended
Mar. 31, 2025
$ / shares
shares
Public Warrants  
Class of Warrant or Right [Line Items]  
Warrant outstanding (in shares) | shares 17,395,947
Exercisable term from closing of initial public offering 12 months
Warrants outstanding, term 5 years
Redemption price of warrants (in dollars per share) | $ / shares $ 0.01
Redemption period 30 days
Warrant redemption condition minimum share price (in dollars per share) | $ / shares $ 18.00
Threshold trading days 20 days
Threshold consecutive trading days 30 days
Threshold number of business days before sending notice of redemption to warrant holders 3 days
Number of securities called by each warrant or right (in shares) | shares 1
Public Warrants | Class A  
Class of Warrant or Right [Line Items]  
Redemption price of warrants (in dollars per share) | $ / shares $ 11.50
Private Placement Warrants  
Class of Warrant or Right [Line Items]  
Warrant outstanding (in shares) | shares 8,000,000
Exercisable term after business combination 30 days