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Filed Pursuant to Rule 424(b)(5)
Registration No. 333-224880
 
PROSPECTUS SUPPLEMENT
(To Prospectus dated May 23, 2018)
1,403,509 Shares
FORTE BIOSCIENCES, INC.
Common Stock

We are offering 1,403,509 shares of our common stock.
Our common stock is listed on Nasdaq Capital Market under the symbol “FBRX.” The last reported sale price of our common stock on October 28, 2020 was $28.66 per share.
We are an emerging growth company as that term is used in the Jumpstart Our Business Startups Act of 2012 and, as such, have elected to comply with certain reduced public company reporting requirements.

Investing in our common stock involves a high degree of risk. Before making an investment decision, please read the information under the heading “Risk Factors” beginning on page S-7 of this prospectus supplement and in the documents incorporated by reference into this prospectus supplement and the accompanying base prospectus.
Neither the Securities and Exchange Commission (the “SEC“) nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

 	  	Per Share	 	  	Total	 	
Public Offering Price	  	$	28.50	 	  	$	40,000,006.50	 	
Underwriting Discounts and Commissions (1)	  	$	1.8525	 	  	$	2,600,000.42	 	
Proceeds to us (before expenses)	  	$	26.6475	 	  	$	37,400,006.08	 	
 
(1)	We have agreed to reimburse the underwriters for certain expenses. See “Underwriting” for a description of the compensation payable to the underwriters.	
We have granted the underwriters an option for a period of up to 30 days from the date of this prospectus supplement to purchase up to an additional 210,526 shares of our common stock. See “Underwriting” for more information.
Delivery of the shares of common stock is expected to be made on or about November 2, 2020.

Joint Book-Running Managers

			
Ladenburg Thalmann	 	Truist Securities                       	 	Chardan	
Co-Manager
Brookline Capital Markets
a division of Arcadia Securities, LLC
The date of this prospectus supplement is October 29, 2020

Table of Contents
TABLE OF CONTENTS
Prospectus Supplement

 	  	Page	 	
ABOUT THIS PROSPECTUS SUPPLEMENT	  	 	S-1	 	
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	  	 	S-2	 	
PROSPECTUS SUPPLEMENT SUMMARY	  	 	S-3	 	
THE OFFERING	  	 	S-6	 	
RISK FACTORS	  	 	S-7	 	
USE OF PROCEEDS	  	 	S-9	 	
DILUTION	  	 	S-10	 	
UNDERWRITING	  	 	S-19	 	
LEGAL MATTERS	  	 	S-25	 	
EXPERTS	  	 	S-25	 	
WHERE YOU CAN FIND ADDITIONAL INFORMATION	  	 	S-26	 	
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE	  	 	S-26	 	
Prospectus

ABOUT THIS PROSPECTUS	  	 	i	 	
SUMMARY	  	 	1	 	
RISK FACTORS	  	 	6	 	
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	  	 	7	 	
RATIO OF EARNINGS TO FIXED CHARGES	  	 	8	 	
USE OF PROCEEDS	  	 	8	 	
DESCRIPTION OF CAPITAL STOCK	  	 	8	 	
DESCRIPTION OF DEBT SECURITIES	  	 	12	 	
DESCRIPTION OF WARRANTS	  	 	19	 	
LEGAL OWNERSHIP OF SECURITIES	  	 	21	 	
PLAN OF DISTRIBUTION	  	 	24	 	
LEGAL MATTERS	  	 	26	 	
EXPERTS	  	 	26	 	
WHERE YOU CAN FIND MORE INFORMATION	  	 	26	 	
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE	  	 	27	 	
DISCLOSURE OF COMMISSION’S POSITION ON INDEMNIFICATION FOR SECURITIES ACT LIABILITY	  	 	28	 	
 
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ABOUT THIS PROSPECTUS SUPPLEMENT
This document is in two parts. The first part is the prospectus supplement, including the documents incorporated by reference, which describes the specific terms of this offering. The second part, the accompanying prospectus, including the documents incorporated by reference, provides more general information. Before you invest, you should carefully read this prospectus supplement, the accompanying prospectus, all information incorporated by reference herein and therein, as well as the additional information described under “Where You Can Find Additional Information” on page S-26 of this prospectus supplement. These documents contain information you should consider when making your investment decision. This prospectus supplement may add, update or change information contained in the accompanying prospectus. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, on the other hand, you should rely on the information in this prospectus supplement. If any statement in one of these documents is inconsistent with a statement in another document having a later date — for example, a document filed after the date of this prospectus supplement and incorporated by reference in this prospectus supplement and the accompanying prospectus — the statement in the document having the later date modifies or supersedes the earlier statement.
This prospectus supplement is part of a registration statement that we filed with the SEC using a “shelf” registration process. Under the shelf registration process, we may from time to time offer and sell any combination of the securities described in the accompanying prospectus up to a total dollar amount of $100.0 million, of which this offering is a part.
You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and in any free writing prospectuses we may provide to you in connection with this offering. We have not, and Ladenburg Thalmann & Co. Inc. (“Ladenburg”) has not, authorized any other person to provide you with any information that is different. If anyone provides you with different or inconsistent information, you should not rely on it. We and Ladenburg take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Additionally, you should assume that the information appearing in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference herein and therein, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.
We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference in the accompanying prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.
This prospectus supplement, the accompanying prospectus and the information incorporated herein and therein by reference include trademarks, service marks and tradenames owned by us or other companies. All
 
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trademarks, service marks and tradenames included or incorporated by reference in this prospectus supplement or the accompanying prospectus are the property of their respective owners.
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
This prospectus supplement and our SEC filings that are incorporated by reference into this prospectus supplement contain or incorporate by reference forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). These forward-looking statements are based on current expectations and beliefs and involve numerous risks and uncertainties that could cause actual results to differ materially from expectations. These forward-looking statements should not be relied upon as predictions of future events as it cannot be assured that the events or circumstances reflected in these statements will be achieved or will occur. You can identify forward-looking statements by the use of forward-looking terminology including “anticipates,” “believes,” “could,” “seeks,” “estimates,” “expects,” “intends,” “may,” “plans,” “potential,” “predicts,” “projects,” “pro forma,” “should,” “will,” “would,” or the negative of these words and phrases or other variations of these words and phrases or comparable terminology. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. For example, forward-looking statements include, but are not limited to statements about:
 
 	•	 	any statements of the plans, strategies and objectives of management for future operations;	
 
 	•	 	any statements concerning proposed new products, services or developments;	
 
 	•	 	any statements regarding any business disruption or potential impact to its business due to COVID-19;	
 
 	•	 	any statements regarding future economic conditions or performance;	
 
 	•	 	our ability to protect our intellectual property and operate our business without infringing upon the intellectual property rights of others;	
 
 	•	 	the timing, scope and likelihood of regulatory filings and approvals or our current or future product candidates;	
 
 	•	 	our estimates regarding the sufficiency of our cash resources and our need for additional funding; and	
 
 	•	 	our intended use of the net proceeds from offerings of our securities under this prospectus supplement.	
Forward-looking statements reflect our current views with respect to future events, are based on assumptions and are subject to risks and uncertainties. We cannot guarantee that we actually will achieve the plans, intentions or expectations expressed in our forward-looking statements and you should not place undue reliance on these statements. There are a number of important factors that could cause our actual results to differ materially from those indicated or implied by forward-looking statements. These important factors include those discussed under the heading “Risk Factors” contained or incorporated in this prospectus supplement and the accompanying prospectus and any free writing prospectus we may authorize for use in connection with a specific offering. These factors and the other cautionary statements made in this prospectus supplement and the accompanying prospectus should be read as being applicable to all related forward-looking statements whenever they appear in this prospectus supplement and the accompanying prospectus. Except as required by law, we do not assume any obligation to update any forward-looking statement. We disclaim any intention or obligation to update or revise any forward-looking statement, whether as a result of new information, future events or otherwise.
 
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PROSPECTUS SUPPLEMENT SUMMARY
This summary highlights selected information about us, this offering and information appearing elsewhere in this prospectus supplement and in the documents we incorporate by reference. This summary is not complete and does not contain all the information you should consider before investing in our common stock pursuant to this prospectus supplement and the accompanying prospectus. Before making an investment decision, to fully understand this offering and its consequences to you, you should carefully read this entire prospectus supplement and the accompanying prospectus, including “Risk Factors” beginning on page S-7 of this prospectus supplement and the financial statements and related notes and the other information that we incorporated by reference herein, including our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and any other filings that we file with the SEC from time to time.
Unless the context otherwise requires, all references in this prospectus to “Forte,” “we,” “us,” “our,” “the Company” or similar words refer to Forte Biosciences, Inc., together with our consolidated subsidiary, Forte Subsidiary, Inc.
Overview
We are a clinical-stage biopharmaceutical company focused on advancing through clinical trials our lead product candidate, FB-401, which is a live biotherapeutic for the treatment of inflammatory skin disease, including pediatric and adult patients with atopic dermatitis (“AD”). There is currently a significant unmet need for safe and effective therapies for pediatric AD patients. FB401 was developed in collaboration with the National Institutes of Health (“NIH”), and the National Institute of Allergy and Infectious Diseases (“NIAID”).
We are developing a new approach to treating inflammatory skin disease using a topical live biotherapeutic, FB-401, which consists of three therapeutic strains of a commensal gram-negative bacteria, Roseomonas mucosa, that were specifically selected for their impact on key parameters of inflammatory skin disease. Genetic- based microbiome identification revealed significant differences in the Gram-negative skin biome between AD patients and healthy volunteers (“HV”). Over 50% of AD patients did not have any culturable Gram-negative flora. Our extensive preclinical and mechanism of action data demonstrate that FB-401 improves atopic dermatitis disease parameters by driving tissue repair and anti-inflammation as well as suppressing potentially harmful bacteria like S. aureus. Specifically, we believe that FB-401:
 
 	•	 	drives immune pathways that are defective;	
 
 	•	 	suppresses Staphylococcus aureus growth; and	
 
 	•	 	improves skin barrier function.	
To date, a Phase 1/2a study has been completed with pediatric and adult patients, demonstrating significant reduction in atopic dermatitis disease and pruritus, as well as control of S. aureus while tapering/eliminating steroid use. We also initiated a double-blinded randomized Phase 2 clinical trial for mild to moderate AD in September 2020.
Recent Developments
Merger
Forte entered into a business combination (“Merger”) between Forte Subsidiary, Inc. (“Forte Subsidiary”) and Tocagen, Inc. (“Tocagen”), a publicly traded biotechnology company. The Merger closed on June 15, 2020, in which Telluride Merger Sub, Inc. a wholly-owned subsidiary of Tocagen, merged with and into Forte Subsidiary, with Forte Subsidiary surviving that Merger as a wholly-owned subsidiary of Tocagen. Immediately

 
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prior to the closing of the Merger, the then outstanding shares of Tocagen common stock were adjusted with a reverse stock split of 15 to 1 (the “Reverse Stock Split”). At the closing of the Merger, each share of Forte Subsidiary’s common stock was converted into the right to receive approximately 3.1624 shares of Tocagen common stock (before giving effect to the reverse split). Immediately prior to closing of the Merger, Tocagen changed its name to Forte Biosciences, Inc. Our common stock is publicly traded on the Nasdaq Capital Market under the ticker symbol FRBX. Prior to the Merger, Forte Subsidiary was a privately held company incorporated in Delaware on May 3, 2017.
Net loss per share, basic and diluted for the years ended December 31, 2019, 2018 and 2017, adjusted to reflect the Reverse Stock Split are $(40.32), $(36.61) and $(39.97), respectively. The weighted-average shares outstanding to compute net loss per share, basic and diluted for the same years adjusted to reflect the Reverse Stock Split are 1,575,361, 1,337,302, and 973,840, respectively. The common shares outstanding at period end for the same years adjusted to reflect the Reverse Stock Split are 1,593,284, 1,533,343, and 1,325,503, respectively.
Net loss per share, basic and diluted for the quarters ended March 31, 2020 and 2019, adjusted to reflect the Reverse Stock Split are $(6.45) and $(11.12), respectively. The weighted-average shares outstanding to compute net loss per share, basic and diluted for the same quarters adjusted to reflect the Reverse Stock Split are 1,593,525 and 1,536,063, respectively. The common shares outstanding at period end for the same quarters adjusted to reflect the Reverse Stock Split are 1,594,314 and 1,547,390, respectively.
FB-401 Clinical Trial
On September 29, 2020, the Company announced that the first patient had been dosed in the clinical trial of FB-401 for the treatment of atopic dermatitis. The multi-center, placebo controlled clinical trial of FB-401 is expected to enroll approximately 124 pediatric, adolescent and adult subjects aged 2 years of age and older with AD. The primary endpoint of the trial is EASI-50, which is a measure of the proportion of patients that achieve at least a 50% improvement in the AD disease burden as measured by the Eczema Area and Severity Index (“EASI”). In the previously completed Phase 1/2a trial, the pediatric cohort enrolled AD patients with mild, moderate and severe disease, ranging in age from 3 to 16 years. Those patients were treated topically with FB-401 for 16 weeks (twice weekly for 12 weeks and every other day for the final 4 weeks). EASI-50 was achieved by 90% of the pediatric patients and 100% of the subset of moderate-to-severe pediatric patients. The mean improvement in the EASI score was 77%, with improvements observed on all actively treated body regions. The activity was durable through the follow-up period of up to 8 months after the end of treatment. Pruritus (itch) also improved by an average of 4 points (mean improvement of 58%). FB-401 has been shown to drive tissue repair and anti-inflammation while controlling potentially harmful bacteria like Staphylococcus aureus.
FDA Fast-Track Designation
On October 26, 2020, the Company announced that the U.S. Food and Drug Administration (“FDA”) had granted Fast Track Designation to FB-401 for the treatment of AD.
Corporate Information
Our principal executive offices are located at 1124 W Carson Street MRL Building 3-320, Torrance, California 90502, and our telephone number at that address is (310) 618-6994. Our corporate website is located at www.fortebiorx.com. The information contained on, or that can be accessed through, our website is not a part of this prospectus supplement. Investors should not rely on any such information in deciding whether to purchase our common stock. We have included our website address in this prospectus supplement solely as an inactive textual reference.

 
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We make available free of charge through our website our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The information contained in, or that can be accessed through, our website is not part of this prospectus supplement.
Implications of Being an Emerging Growth Company
We qualify as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). As an emerging growth company, we intend to take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies. These provisions include:
 
 	•	 	allowance to provide only two years of audited financial statements in addition to any required unaudited interim financial statements with correspondingly reduced “Management’s Discussion and Analysis of Financial Condition and Results of Operations” disclosure;	
 
 	•	 	reduced disclosure about our executive compensation arrangements;	
 
 	•	 	exemption from the requirements of holding non-binding advisory votes on executive compensation or golden parachute arrangements; and	
 
 	•	 	exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting.	
We may take advantage of these provisions for up to five years or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company on the date that is the earliest of: (i) the last day of the fiscal year in which we have total annual gross revenues of $1.07 billion or more; (ii) the last day of our fiscal year following the fifth anniversary of the date of the completion of our initial public offering; (iii) the date on which we have issued more than $1.07 billion in nonconvertible debt during the previous three years; or (iv) the date on which we are deemed to be a large accelerated filer under the rules of the SEC. Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. We have elected not to avail our self of this exemption from new or revised accounting standards and, therefore, will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

 
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THE OFFERING
 
Common stock offered by us	1,403,509 shares.	
 
Common stock to be outstanding after this offering	12,601,824 shares (or 12,812,350 shares if the underwriters’ option to purchase additional shares is exercised in full).	
 
Underwriters’ option to purchase additional shares	We have granted the underwriters a 30-day option from the date of this prospectus supplement to purchase up to 210,526 additional shares of our common stock at the public offering price, less underwriting discounts and commissions.	
 
Use of proceeds	We intend to use the net proceeds from this offering, together with our existing cash and cash equivalents, for working capital and general corporate purposes, which include, but are not limited to, the funding of clinical development of, and pursuing regulatory approval for, our product candidates, and general and administrative expenses. Please see “Use of Proceeds” on page S-9.	
 
Risk factors	This investment involves a high degree of risk. See “Risk Factors” beginning on page S-7 of this prospectus supplement, as well as the other information included in or incorporated by reference in this prospectus supplement and the accompanying prospectus, for a discussion of risks you should carefully consider before investing in our securities.	
 
Nasdaq Capital Market symbol	FBRX	
The number of shares of our common stock that will be outstanding after this offering is based on 11,198,315 shares of common stock outstanding as of June 30, 2020 and excludes:
 
 	•	 	2,752,546 shares of our common stock issuable upon exercise of warrants outstanding as of June 30, 2020, with an exercise price of $10.56 per share and 4,434 shares of our common stock issuable upon exercise of warrants outstanding as of June 30, 2020 with an exercise price of $140.25 per share;	
 
 	•	 	821,910 shares of our common stock issuable upon exercise of options outstanding as of June 30, 2020, with a weighted-average exercise price of $6.21 per share; and	
 
 	•	 	500,000 shares of our common stock available for future grants under our 2020 Inducement Equity Incentive Plan adopted as of July 26, 2020.	
Unless otherwise indicated, all information in this prospectus supplement assumes no exercise of the underwriters’ option to purchase additional shares of our common stock.

 
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RISK FACTORS
Investing in our securities involves a high degree of risk and uncertainty. In addition to the other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus, you should carefully consider the risks described below, before making an investment decision with respect to the securities. We expect to update these Risk Factors from time to time in the periodic and current reports that we file with the SEC after the date of this prospectus supplement. These updated Risk Factors will be incorporated by reference in this prospectus supplement and the accompanying prospectus. Please refer to these subsequent reports for additional information relating to the risks associated with investing in our common stock. If any of such risks and uncertainties actually occurs, our business, financial condition, and results of operations could be severely harmed. This could cause the trading price of our common stock to decline, and you could lose all or part of your investment. Our actual results could differ materially from those anticipated in the forward-looking statements made throughout this prospectus supplement or the documents incorporated by reference into this prospectus supplement and the accompanying prospectus as a result of different factors, including the risks we face described below.
Risks Related to this Offering
You may experience immediate and substantial dilution in the net tangible book value per share of the common stock you purchase.
The price per share of our common stock being offered is higher than the net tangible book value per share of our common stock outstanding prior to this offering. Assuming that an aggregate of 1,403,509 shares are sold at a price of $28.50 per share for aggregate proceeds of approximately $40.0 million in this offering, and after deducting commissions and estimated aggregate offering expenses payable by us, you will suffer immediate and substantial dilution of $23.57 per share, representing the difference between the as adjusted net tangible book value per share of our common stock as of June 30, 2020, after giving effect to this offering and the offering price. See the section entitled “Dilution” below for a more detailed discussion of the dilution you will incur if you purchase common stock in this offering.
You may experience future dilution as a result of future equity offerings.
In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock or other securities convertible into or exchangeable for our common stock in future transactions may be higher or lower than the price per share in this offering. In addition, we have an equity sales agreement in place with Ladenburg to sell up to $10.0 million worth of shares of our common stock, from time to time, through an “at the market” equity offering program under which Ladenburg will act as sales agent.
To the extent we sell additional shares of common stock under our “at the market” equity offering program, grant additional awards under our equity incentive plans, or otherwise issue additional equity, you could experience dilution, and, as a result, the market price of our common stock may decline.
Our management will have broad discretion over the use of the net proceeds from this offering, you may not agree with how we use the proceeds and the proceeds may not be invested successfully.
We have not designated any portion of the net proceeds from this offering to be used for any particular purpose. Accordingly, our management will have broad discretion as to the use of the net proceeds from this offering and could use them for purposes other than those contemplated at the time of commencement of this offering. Accordingly, you will be relying on the judgment of our management with regard to the use of these net
 
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proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. It is possible that, pending their use, we may invest the net proceeds in a way that does not yield a favorable, or any, return for our company. Our failure to apply these funds effectively could have a material adverse effect on our business, delay the development of our product candidates and cause the price of our common stock to decline.
Because we do not intend to declare cash dividends on our shares of common stock in the foreseeable future, stockholders must rely on appreciation of the value of our common stock for any return on their investment.
We have never declared or paid cash dividends on our common stock. We currently anticipate that we will retain future earnings for the development, operation and expansion of our business and do not anticipate declaring or paying any cash dividends in the foreseeable future. In addition, the terms of any future debt agreements may preclude us from paying dividends. As a result, we expect that only appreciation of the price of our common stock, if any, will provide a return to investors in this offering for the foreseeable future.
A substantial number of shares of common stock may be sold in the market following this offering, which may depress the market price for our common stock.
We maintain a shelf registration statement on Form S-3 with the SEC pursuant to which we may, from time to time, sell up to an aggregate of $100.0 million of our common stock, preferred stock, warrants, debt securities or units. We have sold, and plan in the future to sell, shares of our common stock in underwritten offerings and have established, and may in the future establish, “at-the-market” offering programs pursuant to which we may offer and sell shares of our common stock.
Sales of a substantial number of shares of our common stock in the public market following this offering could cause the market price of our common stock to decline. These sales, or the perception in the market that our officers, directors or the holders of a large number of shares of our common stock intend to sell shares, could reduce the market price of our common stock. A substantial majority of the outstanding shares of our common stock are, and the shares of common stock sold in this offering upon issuance will be, freely tradable without restriction or further registration under the Securities Act. Other than our directors and executive officers, none of our stockholders are subject to any lock-up agreement in connection with this offering.
We cannot predict what effect, if any, sales of our shares in the public market or the availability of shares for sale will have on the market price of our common stock. Future sales of substantial amounts of our common stock in the public market, including shares issued upon exercise of outstanding options, or the perception that such sales may occur, however, could adversely affect the market price of our common stock and also could adversely affect our future ability to raise capital through the sale of our common stock or other equity-related securities of ours at times and prices we believe appropriate.
 
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USE OF PROCEEDS
We estimate that the net proceeds from this offering will be approximately $37.2 million (or $42.8 million if the underwriters exercise their option to purchase additional shares of our common stock in full), after deducting underwriting discounts and commissions and the estimated expenses of this offering.
We will have broad discretion in the use of the net proceeds from this offering. We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents, for working capital and general corporate purposes, which include, but are not limited to, the funding of clinical development of, and pursuing regulatory approval for, our product candidates, including FB-401, and general and administrative expenses.
Additionally, we may use a portion of the net proceeds to us from this offering to expand our business by in-licensing or acquiring, as the case may be, commercial products, product candidates, technologies, compounds, other assets or complementary businesses, using cash or common shares. However, we have no current commitments or obligations to complete any such transactions.
Our expected use of the net proceeds to us from this offering represents our current intentions based upon our present plans and business condition. The amounts and timing of our actual expenditures will depend on numerous factors, including the progress of our research and development efforts, the status of and results from our current or future clinical trials, the timing of regulatory submissions and any unforeseen cash needs. Accordingly, our management will have broad discretion in the application of any net proceeds from this offering.
We have not determined the amount of net proceeds to be used specifically for such purposes. Pending the use of any net proceeds, we expect to invest the net proceeds in interest-bearing, marketable securities.
 
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DILUTION
If you invest in our common stock, your interest will be diluted immediately to the extent of the difference between the public offering price per share and the adjusted net tangible book value per share of our common stock after this offering.
The net tangible book value of our common stock as of June 30, 2020, was approximately $24.9 million, or approximately $2.22 per share, after giving effect to the reverse stock split of 15 to 1 that was effective on June 15, 2020. Net tangible book value per share represents the amount of our total tangible assets, excluding goodwill and intangible assets, less total liabilities, divided by the total number of shares of our common stock outstanding. Dilution per share to new investors represents the difference between the amount per share paid by purchasers for each share of common stock in this offering and the net tangible book value per share of our common stock immediately following the completion of this offering.
After giving effect to the sale of shares of common stock offered by us in this offering at the public offering price of $28.50 per share, and after deducting estimated commissions and estimated offering expenses, our as-adjusted net tangible book value as of June 30, 2020 would have been approximately $62.1 million or approximately $4.93 per share. This represents an immediate increase in net tangible book value of approximately $2.71 per share to our existing stockholders and an immediate dilution in as-adjusted net tangible book value of approximately $23.57 per share to purchasers of our common stock in this offering, as illustrated by the following table:

Public offering price per share	  				  	$	28.50	 	
Net tangible book value per share as of June 30, 2020	  	$	2.22	 	  				
Increase per share attributable to this offering	  	$	2.71	 	  				
As-adjusted net tangible book value per share as of June 30, 2020, after giving effect to this offering	  				  	$	4.93	 	
	  	 	 	 	  	 	 	 	
Dilution per share to new investors participating in this offering	  				  	$	23.57	 	
	  				  	 	 	 	
The information above assumes that the underwriters do not exercise their option to purchase additional shares. If the underwriters’ option to purchase additional shares is exercised in full, our as adjusted net tangible book value per share at June 30, 2020, after giving effect to this offering, would have been approximately $5.28 per share, and the dilution in as adjusted net tangible book value per share to investors in this offering would have been approximately $23.22 per share.
The table above is based on 11,198,315 shares of our common stock outstanding as of June 30, 2020, after giving effect to the reverse stock split of 15 to 1 that was effective on June 15, 2020 and excludes the following shares which have also been updated for the reverse stock split:
 
 	•	 	2,752,546 shares of our common stock issuable upon exercise of warrants outstanding as of June 30, 2020, with an exercise price of $10.56 per share and 4,434 shares of our common stock issuable upon exercise of warrants outstanding as of June 30, 2020 with an exercise price of $140.25 per share;	
 
 	•	 	821,910 shares of our common stock issuable upon exercise of options outstanding as of June 30, 2020, with a weighted-average exercise price of $6.21 per share; and	
 
 	•	 	500,000 shares of our common stock available for future grants under our 2020 Inducement Equity Incentive Plan adopted as of July 26, 2020.	
To the extent that after June 30, 2020 any outstanding options or warrants were or are exercised, new equity awards were or are issued under our equity incentive plan, or we otherwise issued or issue additional shares of common stock in the future at prices per share below the price per share for any shares sold in this offering, there will be further dilution to new investors.
 
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DESCRIPTION OF OUR CAPITAL STOCK
As of the date of this supplemental prospectus, our amended and restated certificate of incorporation authorizes us to issue 200,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of preferred stock, par value $0.001 per share. All of our authorized preferred stock is undesignated.
The following is a summary of the rights of our common and preferred stockholders, of some of the provisions of our amended and restated certificate of incorporation and amended and restated bylaws and of the Delaware General Corporation Law (the “DGCL”). This summary is not complete. For more detailed information, please see our amended and restated certificate of incorporation and amended and restated bylaws, as well as the relevant provisions of the DGCL.
Common Stock
Voting. Our common stock is entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, including the election of directors, and does not have cumulative voting rights. Accordingly, the holders of a majority of the shares of our common stock entitled to vote in any election of directors can elect all of the directors standing for election.
Dividends. Subject to preferences that may be applicable to any then-outstanding preferred stock, the holders of our common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds.
Liquidation. In the event of our liquidation, dissolution or winding-up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.
Rights and Preferences. Holders of our common stock have no preemptive, conversion or subscription rights, and there are no redemption or sinking fund provisions applicable to its common stock. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.
Preferred Stock
Under our amended and restated certificate of incorporation, our board of directors has the authority, without further action by stockholders, to designate up to 10,000,000 shares of preferred stock in one or more series and to fix or alter, from time to time, the designations, powers and rights of each series of preferred stock and the qualifications, limitations or restrictions of any series of preferred stock, including dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions), redemption price or prices, and the liquidation preference of any wholly unissued series of preferred stock, any or all of which may be greater than the rights of our common stock, and to establish the number of shares constituting any such series. To date, none of the 10,000,000 authorized shares of preferred stock have been designated by our board of directors.
Our board of directors will fix the rights, preferences, privileges, qualifications and restrictions of the preferred stock of each series in the certificate of designation relating to each such series, including:
 
 	•	 	the title and stated value;	
 
 	•	 	the liquidation preference per share;	
 
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 	•	 	the dividend rate per share, dividend period, payment date or dates and method of calculation for dividends;	
 
 	•	 	whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;	
 
 	•	 	Our right, if any, to defer payment of dividends and the maximum length of any such deferral period;	
 
 	•	 	the procedures for any auction and remarketing, if any;	
 
 	•	 	the provisions for a sinking fund, if any;	
 
 	•	 	the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;	
 
 	•	 	whether the preferred stock will be convertible into our common stock or other securities of ours, including warrants, and, if applicable, the conversion price, or how it will be calculated, and under what circumstances and the mechanism by which it may be adjusted, and the conversion period;	
 
 	•	 	whether the preferred stock will be exchangeable into debt securities or other securities of ours, and, if applicable, the exchange price, or how it will be calculated, and under what circumstances it may be adjusted, and the exchange period;	
 
 	•	 	voting rights, if any;	
 
 	•	 	preemptive rights, if any;	
 
 	•	 	restrictions on transfer, sale or other assignment, if any;	
 
 	•	 	whether interests in the preferred stock will be represented by depositary shares;	
 
 	•	 	the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;	
 
 	•	 	any limitations on issuances of any class or series of preferred stock ranking senior to or on parity with the series of preferred stock being issued as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and	
 
 	•	 	any other specific terms, rights, preferences, privileges, qualifications or limitations of, or restrictions on the preferred stock.	
The laws of the state of Delaware, the state of our incorporation, provide that the holders of preferred stock will have the right to vote separately, as a class, on any proposal involving fundamental changes in the rights of holders of such preferred stock. This right is in addition to any voting rights that may be provided for in the applicable certificate of designation.
The issuance of preferred stock could adversely affect the voting power, conversion or other rights of holders of our common stock and reduce the likelihood that common stockholders will receive dividend payments and payments upon liquidation. Preferred stock could be issued quickly with terms designed to delay, deter or prevent a change in our control or make removal of management more difficult. Additionally, the issuance of preferred stock may have the effect of decreasing the market price of our common stock.
 
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Anti-Takeover Effects of Provisions of Our Amended and Restated Certificate of Incorporation, Our Amended and Restated Bylaws and Delaware Law
Delaware Anti-Takeover Law
We are subject to Section 203 of the DGCL, which generally prohibits a public Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:
 
 	•	 	prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;	
 
 	•	 	the interested stockholder owned at least 85% of the voting stock of the corporation outstanding upon consummation of the transaction, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or	
 
 	•	 	on or subsequent to the consummation of the transaction, the business combination is approved by the board and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock which is not owned by the interested stockholder.	
Section 203 of the DGCL defines a business combination to include:
 
 	•	 	any merger or consolidation involving the corporation and the interested stockholder;	
 
 	•	 	any sale, transfer, pledge or other disposition involving the interested stockholder of 10% or more of the assets of the corporation;	
 
 	•	 	subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder;	
 
 	•	 	subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder; and	
 
 	•	 	the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.	
In general, Section 203 of the DGCL defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.
Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws
Provisions of our amended and restated certificate of incorporation and amended and restated bylaws, may delay or discourage transactions involving an actual or potential change in its control or change in its management, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. Therefore, these provisions could adversely affect the price of our common stock. Among other things, our amended and restated certificate of incorporation and amended and restated bylaws:
 
 	•	 	permit our board of directors to issue up to 10,000,000 shares of preferred stock, with any rights, preferences and privileges as they may designate;	
 
 	•	 	provide that the authorized number of directors may be changed only by resolution adopted by a majority of our board of directors;	
 
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 	•	 	provide that the board of directors or any individual director may only be removed with cause and the affirmative vote of the holders of at least 66 2/3% of the voting power of all of our then outstanding common stock;	
 
 	•	 	provide that all vacancies, including newly created directorships, may, except as otherwise required by law or subject to the rights of holders of preferred stock as designated from time to time, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;	
 
 	•	 	divides our board of directors into three classes;	
 
 	•	 	require that any action to be taken by its stockholders must be effected at a duly called annual or special meeting of stockholders and not be taken by written consent or electronic transmission;	
 
 	•	 	provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide notice in writing in a timely manner and also specify requirements as to the form and content of a stockholder’s notice;	
 
 	•	 	do not provide for cumulative voting rights (therefore allowing the holders of a majority of the shares of our common stock entitled to vote in any election of directors to elect all of the directors standing for election, if they should so choose);	
 
 	•	 	provide that special meetings of its stockholders may be called only by the chairman of our board of directors, its Chief Executive Officer or by our board of directors pursuant to a resolution adopted by a majority of the total number of authorized directors (whether or not there exists any vacancies); and	
 
 	•	 	provide that the Court of Chancery of the State of Delaware will be the sole and exclusive forum for (1) any derivative action or proceeding brought on its behalf, (2) any action asserting a claim of breach of a fiduciary duty owed by any of its directors or officers to its or its stockholders, (3) any action asserting a claim against it arising pursuant to any provision of the DGCL or its amended and restated certificate of incorporation or amended and restated bylaws, or (4) any action asserting a claim against it governed by the internal affairs doctrine.	
The amendment of any of these provisions, with the exception of the ability of our board of directors to issue shares of preferred stock and designate any rights, preferences and privileges thereto, would require the affirmative vote of the holders of at least 66 2/3% of the voting power of all of our outstanding common stock.
Transfer Agent and Registrar
The transfer agent and registrar for our common stock is Computershare Trust Company, N.A. The transfer agent and registrar’s address is 250 Royall Street, Canton, Massachusetts 02021.
Listing on the Nasdaq Capital Market
Our common stock is listed on the Nasdaq Capital Market under the symbol “FBRX”.
 
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MATERIAL U.S. FEDERAL INCOME AND ESTATE TAX CONSEQUENCES TO NON-U.S. HOLDERS
The following is a summary of the material U.S. federal income tax consequences of the ownership and disposition of our common stock to non-U.S. holders, but does not purport to be a complete analysis of all the potential tax considerations relating thereto. This summary is based upon the provisions of the Internal Revenue Code of 1986, as amended (the “Code”), Treasury regulations promulgated thereunder, administrative rulings and judicial decisions, all as of the date hereof. These authorities may be changed, possibly retroactively, so as to result in U.S. federal tax consequences different from those set forth below. We have not sought any ruling from the Internal Revenue Service (the “IRS”) with respect to the statements made and the conclusions reached in the following summary, and there can be no assurance that the IRS will agree with such statements and conclusions.
This summary also does not address the tax considerations arising under the laws of any non-U.S., state or local jurisdiction or under U.S. federal gift and estate tax laws, except to the limited extent below. In addition, this discussion does not address tax considerations applicable to an investor’s particular circumstances or to investors that may be subject to special tax rules, including, without limitation:
 
 	•	 	banks, insurance companies or other financial institutions;	
 
 	•	 	persons subject to the alternative minimum tax or net investment income tax;	
 
 	•	 	tax-exempt organizations or governmental organizations;	
 
 	•	 	controlled foreign corporations, passive foreign investment companies and corporations that accumulate earnings to avoid United States federal income tax;	
 
 	•	 	brokers or dealers in securities or currencies;	
 
 	•	 	traders in securities that elect to use a mark-to-market method of accounting for their securities holdings;	
 
 	•	 	persons that own, or are deemed to own, more than five percent of our capital stock (except to the extent specifically set forth below);	
 
 	•	 	certain former citizens or long-term residents of the United States;	
 
 	•	 	entities or arrangements classified as partnerships for U.S. federal income tax purposes and other pass-through entities (and investors therein);	
 
 	•	 	persons who hold our common stock as a position in a hedging transaction, “straddle,” “conversion transaction” or other risk reduction transaction;	
 
 	•	 	persons who hold or receive our common stock pursuant to the exercise of any employee stock option or otherwise as compensation;	
 
 	•	 	persons who do not hold our common stock as a capital asset (within the meaning of Section 1221 of the Code); or	
 
 	•	 	persons deemed to sell our common stock under the constructive sale provisions of the Code.	
In addition, if a partnership or entity or arrangement classified as a partnership for U.S. federal income tax purposes holds our common stock, the tax treatment of a partner generally will depend on the status of the partner and upon the activities of the partnership. Accordingly, partnerships that hold our common stock, and partners in such partnerships, should consult their tax advisors.
This discussion is for information purposes only and is not tax or legal advice. You are urged to consult your tax advisor with respect to the application of the U.S. federal income tax laws to your particular situation, as well as any tax consequences of the purchase, ownership and disposition of our common stock arising under the U.S. federal income, estate or gift tax rules or under the laws of any state, local, non-U.S. or other taxing jurisdiction or under any applicable tax treaty.
 
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Non-U.S. Holder Defined
For purposes of this discussion, you are a non-U.S. holder if you are a beneficial owner of our common stock that is not, for U.S. federal income tax purposes:
 
 	•	 	an individual citizen or resident of the United States;	
 
 	•	 	a corporation or other entity taxable as a corporation created or organized in the United States or under the laws of the United States or any political subdivision thereof;	
 
 	•	 	an estate whose income is subject to U.S. federal income tax regardless of its source; or	
 
 	•	 	a trust (x) whose administration is subject to the primary supervision of a U.S. court and which has one or more U.S. persons who have the authority to control all substantial decisions of the trust or (y) which has made an election to be treated as a U.S. person.	
Distributions
We have not made any distributions on our common stock, and we do not plan to make any distributions for the foreseeable future. However, if we do make distributions on our common stock, those payments will constitute dividends for U.S. tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. To the extent those distributions exceed both our current and our accumulated earnings and profits, they will constitute a return of capital and will first reduce your basis in our common stock, but not below zero, and then will be treated as gain from the sale of stock.
Subject to the discussion below on effectively connected income, any dividend paid to you generally will be subject to U.S. withholding tax either at a rate of 30% of the gross amount of the dividend or such lower rate as may be specified by an applicable income tax treaty. In order to receive a reduced treaty rate, you must provide us with an IRS Form W-8BEN, IRS Form W-8BEN-E or other appropriate version of IRS Form W-8 certifying qualification for the reduced rate. A non-U.S. holder of shares of our common stock eligible for a reduced rate of U.S. withholding tax pursuant to an income tax treaty may be able to obtain a refund of any excess amounts withheld by filing an appropriate claim for refund with the IRS. If the non-U.S. holder holds the stock through a financial institution or other agent acting on the non-U.S. holder’s behalf, the non-U.S. holder will be required to provide appropriate documentation to the agent, which then will be required to provide certification to us or our paying agent, either directly or through other intermediaries.
Dividends received by you that are effectively connected with your conduct of a U.S. trade or business (and, if required by an applicable income tax treaty, attributable to a permanent establishment maintained by you in the United States) are generally exempt from such withholding tax. In order to obtain this exemption, you must provide us with an IRS Form W-8ECI properly certifying such exemption. Such effectively connected dividends, although not subject to withholding tax, are taxed at the same rates applicable to U.S. persons, net of certain deductions and credits, subject to an applicable income tax treaty providing otherwise. In addition, if you are a corporate non-U.S. holder, dividends you receive that are effectively connected with your conduct of a U.S. trade or business may also be subject to a branch profits tax at a rate of 30% or such lower rate as may be specified by an applicable income tax treaty.
 
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Gain on Disposition of Our Common Stock
Subject to the discussion below regarding backup withholding and foreign accounts, you generally will not be required to pay U.S. federal income tax on any gain realized upon the sale or other disposition of our common stock unless:
 
 	•	 	the gain is effectively connected with your conduct of a U.S. trade or business (and, if required by an applicable income tax treaty, the gain is attributable to a permanent establishment maintained by you in the United States);	
 
 	•	 	you are an individual who is present in the United States for a period or periods aggregating 183 days or more during the calendar year in which the sale or disposition occurs and certain other conditions are met; or	
 
 	•	 	our common stock constitutes a U.S. real property interest by reason of our status as a “United States real property holding corporation” for U.S. federal income tax purposes (a “USRPHC”), at any time within the shorter of the five-year period preceding your disposition of, or your holding period for, our common stock.	
We believe that we are not currently and will not become a USRPHC. However, because the determination of whether we are a USRPHC depends on the fair market value of our U.S. real property relative to the fair market value of our other business assets, there can be no assurance that we will not become a USRPHC in the future. Even if we become a USRPHC, however, as long as our common stock is regularly traded on an established securities market, such common stock will be treated as U.S. real property interests only if you actually or constructively hold more than five percent of such regularly traded common stock at any time during the applicable period described above.
If you are a non-U.S. holder described in the first bullet above, you will be required to pay tax on the net gain derived from the sale under regular U.S. federal income tax rates, and corporate non-U.S. holders described in the first bullet above may be subject to the branch profits tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. If you are an individual non-U.S. holder described in the second bullet above, you will be required to pay a flat 30% tax on the gain derived from the sale, which gain may be offset by U.S. source capital losses (even though you are not considered a resident of the United States, provided you have timely filed U.S. federal income tax returns with respect to such losses). You should consult your tax advisor regarding any applicable income tax or other treaties that may provide for different rules.
Backup Withholding and Information Reporting
Generally, we must report annually to the IRS the amount of dividends paid to you, your name and address, and the amount of tax withheld, if any. A similar report is sent to you. Pursuant to applicable income tax treaties or other agreements, the IRS may make these reports available to tax authorities in your country of residence.
Payments of dividends or of proceeds on the disposition of stock made to you may be subject to information reporting and backup withholding at a current rate of 24% unless you establish an exemption, for example by properly certifying your non-U.S. status on an IRS Form W-8BEN, IRS Form W-8BEN-E or another appropriate version of IRS Form W8. Notwithstanding the foregoing, backup withholding and information reporting may apply if either we or our paying agent has actual knowledge, or reason to know, that you are a U.S. person.
Backup withholding is not an additional tax; rather, the U.S. federal income tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund or credit may generally be obtained from the IRS, provided that the required information is furnished to the IRS in a timely manner.
 
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FATCA
Provisions commonly referred to as “FATCA,” impose a U.S. federal withholding tax at a rate of 30% on dividends on and gross proceeds from the sale or other disposition of our common stock paid to a “foreign financial institution” (as specially defined under the FATCA rules), unless such institution enters into an agreement with the U.S. government to withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding the U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners) or otherwise establishes an exemption. FATCA also generally imposes a U.S. federal withholding tax of 30% on dividends on and gross proceeds from the sale or other disposition of our common stock paid to a “non-financial foreign entity” (as specially defined for purposes of these rules) unless such entity provides the withholding agent with a certification identifying certain substantial direct and indirect U.S. owners of the entity, certifies that there are none or otherwise establishes an exemption. The withholding provisions under FATCA generally apply to dividends on our common stock, and subject to the proposed regulations described in the next sentence, will apply with respect to the gross proceeds from the sale or other disposition of our common stock. The Treasury Department has released proposed regulations (the preamble to which specifies that taxpayers are permitted to rely on them pending finalization) which, if finalized in their present form, would eliminate the federal withholding tax of 30% applicable to the gross proceeds of a disposition of our common stock. An intergovernmental agreement between the United States and an applicable foreign country may modify the requirements described in this paragraph. Non-U.S. holders should consult their own tax advisors regarding the possible implications of this legislation on their investment in our common stock.
The preceding discussion of U.S. federal income tax considerations is for general information only. It is not tax advice. Each prospective investor should consult its own tax advisor regarding the particular U.S. federal, state and local and non-U.S. tax consequences of purchasing, holding and disposing of our common stock, including the consequences of any proposed change in applicable laws.
Federal Estate Tax
Our common stock beneficially owned by an individual who is not a citizen or resident of the United States (as defined for U.S. federal estate tax purposes) at the time of death will generally be includable in the decedent’s gross estate for U.S. federal estate tax purposes, unless an applicable estate tax treaty provides otherwise.
 
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UNDERWRITING
We and the underwriters named below are offering the shares of common stock described in this prospectus supplement through Ladenburg as the representative of the underwriters. We have entered into an underwriting agreement with Ladenburg, and subject to the terms and conditions set forth in the underwriting agreement, each underwriter named below has severally agreed to purchase, and we have agreed to sell to that underwriter, the number of shares of common stock set forth opposite the underwriter’s name.

	Underwriter	  	Number of
Shares	 	
Ladenburg Thalmann & Co. Inc.	  	 	449,123	 		
Truist Securities, Inc.	  	 	407,018	 		
Chardan Capital Markets LLC	  	 	407,018	 		
Brookline Capital Markets, a division of Arcadia Securities, LLC	  	 	140,350	 		
Total	  	 	1,403,509	 		
The underwriters have agreed to purchase all of the shares of common stock offered by this prospectus supplement (other than those covered by the option to purchase additional shares of common stock described below), if any are purchased. The shares of common stock offered hereby are expected to be ready for delivery on or about November 2, 2020 against payment in immediately available funds.
The underwriters are offering the shares of common stock subject to various conditions and may reject all or part of any order. The representative of the underwriters has advised us that the underwriters propose initially to offer the shares of common stock to the public at the public offering price set forth on the cover page of this prospectus supplement and at a price less a concession not in excess of $1.1115 per share to brokers and dealers. After the shares of common stock are released for sale to the public, the representative may change the offering price, the concession, and other selling terms at various times.
The following table shows the underwriting discounts and commissions that we are to pay to the underwriters in connection with this offering, before expenses.

 	  	Per Share	 	  	Total	 	
Public offering price	  	$	28.50	 	  	$	40,000,006.50	 	
Underwriting discounts and commissions	  	$	1.8525	 	  	$	2,600,000.42	 	
Proceeds, before expenses, to us	  	$	26.6475	 	  	$	37,400,006.08	 	
We estimate that our total expenses of the offering, excluding the estimated underwriting discounts and commissions, will be approximately $195,000, which includes the fees and expenses for which we have agreed to reimburse the underwriters.
We have granted an option to the underwriters, exercisable for 30 days after the date of this prospectus supplement, to purchase up to additional 210,526 shares of our common stock at the public offering price, less underwriting discounts and commissions. If the underwriters exercise all or part of this option, they will purchase shares of our common stock covered by the option at the public offering price that appears on the cover page of this prospectus supplement, less applicable underwriting discounts and commissions. If this option is exercised in full, the total price to the public will be $46.0 million, and the total proceeds to us, before expenses, will be $43.0 million. If the underwriters exercise this option, each underwriter will be obligated, subject to the conditions contained in the underwriting agreement, to purchase a number of additional shares proportionate to that underwriter’s amount reflected in the above table.
 
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Rules of the SEC may limit the ability of the underwriters to bid for or purchase securities before the distribution of the securities is completed. However, the underwriters may engage in the following activities in accordance with the rules:
 
 	•	 	Stabilizing transactions: The representative may make bids or purchases for the purpose of pegging, fixing or maintaining the price of the shares of common stock, so long as stabilizing bids do not exceed a specified maximum.	
 
 	•	 	Syndicate covering transactions: The underwriters may sell more shares of common stock in connection with this offering than the number of shares of common stock that they have committed to purchase. This over-allotment creates a short position for the underwriters. This short sales position may involve either “covered” short sales or “naked” short sales. Covered short sales are short sales made in an amount not greater than the underwriters’ over-allotment option to purchase additional shares of common stock, if applicable. The underwriters may close out any covered short position either by exercising their over-allotment option, if applicable, or by purchasing shares in the open market. To determine how they will close the covered short position, the underwriters will consider, among other things, the price of shares of common stock available for purchase in the open market, as compared to the price at which they may pur-chase shares of common stock through the over-allotment option, if applicable. Naked short sales are short sales in excess of the over-allotment option, if applicable. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that, in the open market after pricing, there may be downward pressure on the price of the shares of common stock that could adversely affect investors who purchase shares of common stock in this offering.	
 
 	•	 	Penalty bids: If the representative purchases shares of common stock in the open market in a stabilizing transaction or syndicate covering transaction, it may reclaim a selling concession from the underwriters and selling group members who sold those shares of common stockas part of this offering.	
 
 	•	 	Passive market making: Market makers in the shares of common stock who are underwriters or prospective underwriters may make bids for or purchases of shares of common stock, subject to limitations, until the time, if ever, at which a stabilizing bid is made.	
Similar to other purchase transactions, the underwriters’ purchases to cover the syndicate short sales or to stabilize the market price of our shares of common stock may have the effect of raising or maintaining the market price of our shares of common stock or preventing or mitigating a decline in the market price of our shares of common stock. As a result, the price of the shares of our common stock may be higher than the price that might otherwise exist in the open market. The imposition of a penalty bid might also have an effect on the price of the shares of common stock if it discourages resales of the shares.
We have agreed to indemnify the underwriters and other specified persons against certain civil liabilities, including liabilities under the Securities Act and the Exchange Act, and to contribute to payments that the underwriters may be required to make in respect of such liabilities.
Lock-Up Agreements
We, and certain of our executive officers and directors, have agreed, subject to specified exceptions, not to directly or indirectly, without the prior written consent of Ladenburg:
 
 	•	 	offer, pledge, assign, encumber, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, any common stock or any securities convertible into or exercisable or exchangeable for common stock;	
 
 	•	 	enter into any swap, hedge or other agreement that transfers, in whole or in part, the economic consequences of ownership of common stock or any securities convertible into or exercisable or	
 
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 	exchangeable for common stock regardless of whether any such transaction is to be settled in securities, in cash or otherwise;	
 
 	•	 	make any demand for, or exercise any right with respect to, the registration under the Securities Act of the offer and sale of any common stock or any securities convertible into or exercisableor exchangeable for common stock; or	
 
 	•	 	publicly announce any intention to do any of the foregoing.	
This restriction, as it pertains to our directors and officers, terminates after the 90th day after the date of this prospectus supplement. Ladenburg may, in its sole discretion and at any time or from time to time before the termination of the lock-up period, as applicable, release us and/or our officers and directors from all or any portion of these lock-up restrictions.
Electronic Delivery of Preliminary Prospectus
A prospectus supplement in electronic format may be delivered to potential investors by one or more of the underwriters participating in this offering. The prospectus supplement in electronic format will be identical to the paper version of such prospectus supplement. Other than the prospectus supplement in electronic format, the information on any underwriter’s website and any information contained in any other website maintained by an underwriter is not part of this prospectus supplement, the accompanying prospectus or the registration statement of which this prospectus supplement and the accompanying prospectus form a part.
Notice to Non-U.S. Investors
European Economic Area
In relation to each Member State of the European Economic Area, no offer of any securities which are the subject of the offering contemplated by this prospectus has been or will be made to the public in that Member State other than any offer where a prospectus has been or will be published in relation to such securities that has been approved by the competent authority in that Member State or, where appropriate, approved in another Member State and notified to the relevant competent authority in that Member State in accordance with the Prospectus Regulation, except that an offer of such securities may be made to the public in that Member State:
 
 	a)	to any legal entity which is a “qualified investor” as defined in the Prospectus Regulation;	
 
 	b)	to fewer than 150, natural or legal persons (other than qualified investors as defined in the Prospectus Regulation), as permitted under the Prospectus Regulation, subject to obtaining the prior consent of the representatives of the underwriters for any such offer; or	
 
 	c)	in any other circumstances falling within Article 1(4) of the Prospectus Regulation,	
provided that no such offer of securities shall require the Company or any of the underwriters to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.
For the purposes of this provision, the expression an “offer to the public” in relation to any securities in any Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to purchase or subscribe the securities, as the same may be varied in that Member State by any measure implementing the Prospectus Regulation in that Member State and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129.
United Kingdom
This prospectus is only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors (as defined in the Prospectus Regulation) that are also (i) investment professionals falling
 
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within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, referred to herein as the “Order”, and/or (ii) high net worth entities falling within Article 49(2)(a) to (d) of the Order and other persons to whom it may lawfully be communicated or caused to be communicated. Each such person is referred to herein as a “Relevant Person”.
This prospectus and its contents are confidential and should not be distributed, published or reproduced (in whole or in part) or disclosed by recipients to any other persons in the United Kingdom. Any person in the United Kingdom that is not a Relevant Person should not act or rely on this document or any of its contents.
Any invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Financial Services and Markets Act 2000 (the “FSMA”)) may only be communicated or caused to be communicated in connection with the issue or sale of the securities in circumstances in which Section 21(1) of the FSMA does not apply. All applicable provisions of the FSMA must be complied with in respect of anything done by any person in relation to the securities in, from or otherwise involving the United Kingdom.
Canada
The common stock may be sold only to purchasers purchasing as principal that are both “accredited investors” as defined in National Instrument 45-106 Prospectus and Registration Exemptions and “permitted clients” as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the common stock must be made in accordance with an exemption from the prospectus requirements and in compliance with the registration requirements of applicable securities laws.
Germany
Each person who is in possession of this prospectus is aware of the fact that no German securities prospectus (wertpapierprospekt) within the meaning of the German Securities Prospectus Act (Wertpapier-prospektgesetz, or the Act) of the Federal Republic of Germany has been or will be published with respect to the shares of our common stock. In particular, each underwriter has represented that it has not engaged and has agreed that it will not engage in a public offering in the Federal Republic of Germany within the meaning of the Act with respect to any of the shares of our common stock otherwise than in accordance with the Act and all other applicable legal and regulatory requirements.
Hong Kong
The common stock may not be offered or sold in Hong Kong by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap. 32, Laws of Hong Kong), or (ii) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap. 32, Laws of Hong Kong) and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to common stock which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.
Singapore
This prospectus has not been and will not be lodged or registered with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or the
 
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invitation for subscription or purchase of the securities may not be issued, circulated or distributed, nor may the securities be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to the public or any member of the public in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore, or the SFA, (ii) to a relevant person as defined under Section 275(2), or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions, specified in Section 275 of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of any other applicable provision of the SFA.
Where the common stock are subscribed or purchased under Section 275 of the SFA by a relevant person which is:
 
 	a)	a corporation (which is not an accredited investor as defined under Section 4A of the SFA) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or	
 
 	b)	a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary is an accredited investor,	
shares, debentures and units of shares and debentures of that corporation or the beneficiaries’ rights and interest in that trust shall not be transferable for six months after that corporation or that trust has acquired the Offer Shares under Section 275 of the SFA except:
 
 	a)	to an institutional investor under Section 274 of the SFA or to a relevant person defined in Section 275(2) of the SFA, or to any person pursuant to an offer that is made on terms that such shares, debentures and units of shares and debentures of that corporation or such rights and interest in that trust are acquired at a consideration of not less than $200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, and further for corporations, in accordance with the conditions, specified in Section 275 of the SFA;	
 
 	b)	where no consideration is or will be given for the transfer; or	
 
 	c)	where the transfer is by operation of law.	
Switzerland
The common stock may not be publicly offered in Switzerland and will not be listed on the SIX Swiss Exchange (the “SIX”) or on any other stock exchange or regulated trading facility in Switzerland. This document has been prepared without regard to the disclosure standards for issuance prospectuses under art. 652a or art. 1156 of the Swiss Code of Obligations or the disclosure standards for listing prospectuses under art. 27 ff. of the SIX Listing Rules or the listing rules of any other stock exchange or regulated trading facility in Switzerland. Neither this document nor any other offering or marketing material relating to the common stock or the offering may be publicly distributed or otherwise made publicly available in Switzerland.
Neither this document nor any other offering or marketing material relating to the offering, or the common stock have been or will be filed with or approved by any Swiss regulatory authority. In particular, this document will not be filed with, and the offer of common stock will not be supervised by, the Swiss Financial Market Supervisory Authority FINMA, and the offer of common stock has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes (“CISA”). Accordingly, no public distribution, offering or advertising, as defined in CISA, its implementing ordinances and notices, and no distribution to any non-qualified investor, as defined in CISA, its implementing ordinances and notices, shall be undertaken in or from Switzerland, and the investor protection afforded to acquirers of interests in collective investment schemes under CISA does not extend to acquirers of common stock.
 
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United Arab Emirates
This offering has not been approved or licensed by the Central Bank of the United Arab Emirates (the “UAE”), Securities and Commodities Authority of the UAE and/or any other relevant licensing authority in the UAE including any licensing authority incorporated under the laws and regulations of any of the free zones established and operating in the territory of the UAE, in particular the Dubai Financial Services Authority (“DFSA”), a regulatory authority of the Dubai International Financial Centre (“DIFC”). The offering does not constitute a public offer of securities in the UAE, DIFC and/or any other free zone in accordance with the Commercial Companies Law, Federal Law No 8 of 1984 (as amended), DFSA Offered Securities Rules and Nasdaq Dubai Listing Rules, accordingly, or otherwise. The common stock may not be offered to the public in the UAE and/or any of the free zones.
The common stock may be offered and issued only to a limited number of investors in the UAE or any of its free zones who qualify as sophisticated investors under the relevant laws and regulations of the UAE or the free zone concerned.
France
This prospectus supplement has not been prepared in the context of a public offering of financial securities in France within the meaning of Article L.411-1 of the French Code Monétaire et Financier and Title I of Book II of the Reglement Général of the Autorité des marchés financiers, or the AMF, and therefore has not been and will not be filed with the AMF for prior approval or submitted for clearance to the AMF. Consequently, the shares of our common stock may not be, directly or indirectly, offered or sold to the public in France and offers and sales of the shares of our common stock may only be made in France to qualified investors (investisseurs qualifiés) acting for their own, as defined in and in accordance with Articles L.411-2 and D.411-1 to D.411-4, D.734-1, D.744-1, D.754-1 and D.764-1 of the French Code Monétaire et Financier. Neither this prospectus supplement nor any other offering material may be released, issued or distributed to the public in France or used in connection with any offer for subscription on sale of the shares of our common stock to the public in France. The subsequent direct or indirect retransfer of the shares of our common stock to the public in France may only be made in compliance with Articles L.411-1, L.411-2, L.412-1 and L.621-8 through L.621-8-3 of the French Code Monétaire et Financier.
 
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LEGAL MATTERS
The validity of the securities offered hereby will be passed upon for us by Wilson Sonsini Goodrich & Rosati Professional Corporation, San Diego, California. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., New York, NY is counsel to the underwriters in connection with this offering.
EXPERTS
Forte Subsidiary, Inc.
The financial statements of Forte Subsidiary, Inc. as of and for the years ended December 31, 2019 and 2018 included in the Form S-4/A (Registration No. 333-237371) filed with the SEC on May 13, 2020, and on Form 8-K filed with the SEC on September 4, 2020, have been audited by Mayer Hoffman McCann P.C., independent registered public accounting firm, as set forth in their report included therein and have been incorporated by reference in this Prospectus Supplement in reliance on the report of Mayer Hoffman McCann P.C., given on the authority of such firm as experts in auditing and accounting in giving said reports.
Forte Biosciences, Inc. (formerly Tocagen Inc.)
Ernst & Young LLP, independent registered public accounting firm, has audited our financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2019, as set forth in their report thereon (which contains an explanatory paragraph describing conditions that raise substantial doubt about the Company’s ability to continue as a going concern as described in Note 1 to the financial statements) which is incorporated by reference in this prospectus supplement and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.
 
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WHERE YOU CAN FIND ADDITIONAL INFORMATION
This prospectus supplement and the accompanying prospectus do not contain all of the information set forth in this registration statement and the exhibits to this registration statement or the documents incorporated by reference herein and therein. For further information with respect to us and the securities that we are offering under this prospectus supplement, we refer you to the registration statement and the exhibits and schedules filed as a part of the registration statement and the documents incorporated by reference herein and therein. You should rely only on the information contained in this prospectus supplement or the accompanying prospectus or incorporated by reference herein or therein. We have not authorized anyone else to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus is accurate as of any date other than the date on the front page of this prospectus supplement, regardless of the time of delivery of this prospectus supplement or any sale of the securities offered hereby.
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov.
We make available, free of charge, through our investor relations website, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, statements of changes in beneficial ownership of securities and amendments to those reports and statements as soon as reasonably practicable after they are filed with the SEC. The address for our website is https://www.fortebiorx.com The contents on our website are not part of this prospectus supplement, and the reference to our website does not constitute incorporation by reference into this prospectus supplement of the information contained at that site.
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC allows us to “incorporate by reference” into this prospectus supplement the information we file with the SEC. This means that we can disclose important information to you by referring you to those documents. Any statement contained in a document incorporated by reference in this prospectus supplement shall be deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained herein, or in any subsequently filed document, which also is incorporated by reference herein, modifies or supersedes such earlier statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement.
We hereby incorporate by reference into this prospectus supplement the following documents (other than the portions of these documents deemed to be “furnished” or not deemed to be “filed,” including the portions of these documents that are furnished under Item 2.02 or Item 7.01 of a Current Report on Form 8-K, including any exhibits included with such Items):
 
 	•	 	our Annual Report on Form 10-K for the fiscal year ended December 31, 2019, filed with the SEC on February 27, 2020, as amended on April 29, 2020 (the “Annual Report”);	
 
 	•	 	our Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2020 and June  30, 2020, filed with the SEC on April 23, 2020 and August 10, 2020, respectively (the “Quarterly Reports”);	
 
 	•	 	our Current Reports on Form 8-K filed with the SEC on September 4, 2020; August  10, 2020 August 10, 2020 (two filings, one amended from an original filing date of June  15, 2020); July 21, 2020; June  15, 2020; June 12, 2020; June  8, 2020; May  1, 2020; April 15, 2020; February 21, 2020; and February 20, 2020 February 20, 2020 (two filings); and	
 
 	•	 	our prospectus dated May  14, 2020, filed with the Securities and Exchange Commission pursuant to Rule 424(b) under the Securities Act, relating to the Registration Statement on Form S-4, as amended (File No. 333-237371), which includes a proxy statement filed pursuant to Section 14 of the Securities Exchange Act.	
 
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All documents that we file with the SEC pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than current reports on Form 8-K, or portions thereof, furnished under Items 2.02 or 7.01 of Form 8-K) (i) after the initial filing date of the registration statement of which this prospectus supplement forms a part and prior to the effectiveness of such registration statement and (ii) after the date of this prospectus supplement and prior to the termination of this offering shall be deemed to be incorporated by reference in this prospectus supplement from the date of filing of the documents, unless we specifically provide otherwise. Information that we file with the SEC will automatically update and may replace information previously filed with the SEC. To the extent that any information contained in any current report on Form 8-K or any exhibit thereto, was or is furnished to, rather than filed with the SEC, such information or exhibit is specifically not incorporated by reference.
Upon written or oral request made to us at the address or telephone number below, we will, at no cost to the requester, provide to each person, including any beneficial owner, to whom this prospectus supplement is delivered, a copy of any or all of the information that has been incorporated by reference in this prospectus supplement (other than an exhibit to a filing, unless that exhibit is specifically incorporated by reference into that filing), but not delivered with this prospectus supplement. You may also access this information on our website
at www.fortebiorx.com by viewing the “SEC Filings” subsection of the “Investor Relations” menu. No additional information on our website is deemed to be part of or incorporated by reference into this prospectus supplement. We have included our website address in this prospectus supplement solely as an inactive textual reference.
Forte Biosciences, Inc.
1124 W Carson Street
MRL Building 3-320
Torrance, California 90502
Attn: Investor Relations
Tel: (310) 618-6994
 
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PROSPECTUS

$100,000,000
Common Stock
Preferred Stock
Debt Securities
Warrants

From time to time, we may offer up to $100,000,000 of any combination of the securities described in this prospectus in one or more offerings. We may also offer securities as may be issuable upon conversion, redemption, repurchase, exchange or exercise of any securities registered hereunder, including any applicable antidilution provisions.
This prospectus provides a general description of the securities we may offer. Each time we offer securities, we will provide specific terms of the securities offered in a supplement to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference, before you invest in any of the securities being offered.

This prospectus may not be used to consummate a sale of any securities unless accompanied by a prospectus supplement.

Our common stock is traded on the Nasdaq Global Select Market under the symbol “TOCA.” On May 22, 2018, the last reported sales price of our common stock was $9.52 per share. The applicable prospectus supplement will contain information, where applicable, as to any other listing on the Nasdaq Global Select Market or any securities market or other exchange of the securities, if any, covered by the prospectus supplement.
We will sell these securities directly to investors, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the section entitled “Plan of Distribution” in this prospectus. If any agents or underwriters are involved in the sale of any securities with respect to which this prospectus is being delivered, the names of such agents or underwriters and any applicable fees, commissions, discounts or over-allotment options will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.
Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus.
NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The date of this prospectus is May 23, 2018.

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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	  	 	i	 	
SUMMARY	  	 	1	 	
RISK FACTORS	  	 	6	 	
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	  	 	7	 	
RATIO OF EARNINGS TO FIXED CHARGES	  	 	8	 	
USE OF PROCEEDS	  	 	8	 	
DESCRIPTION OF CAPITAL STOCK	  	 	8	 	
DESCRIPTION OF DEBT SECURITIES	  	 	12	 	
DESCRIPTION OF WARRANTS	  	 	19	 	
LEGAL OWNERSHIP OF SECURITIES	  	 	21	 	
PLAN OF DISTRIBUTION	  	 	24	 	
LEGAL MATTERS	  	 	26	 	
EXPERTS	  	 	26	 	
WHERE YOU CAN FIND MORE INFORMATION	  	 	26	 	
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE	  	 	27	 	
DISCLOSURE OF COMMISSION’S POSITION ON INDEMNIFICATION FOR SECURITIES ACT LIABILITY	  	 	28	 	

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ABOUT THIS PROSPECTUS
This prospectus is a part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or SEC, utilizing a “shelf” registration process. Under this shelf registration process, we may sell any combination of the securities described in this prospectus in one or more offerings up to a total aggregate offering price of $100,000,000. This prospectus provides you with a general description of the securities we may offer.
Each time we sell securities under this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in any documents that we have incorporated by reference into this prospectus. You should read this prospectus, any applicable prospectus supplement and any related free writing prospectus, together with the information incorporated herein by reference as described under the heading “Incorporation of Certain Information by Reference,” before investing in any of the securities offered.
THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.
Neither we, nor any agent, underwriter or dealer has authorized any person to give any information or to make any representation other than those contained or incorporated by reference in this prospectus, any applicable prospectus supplement or any related free writing prospectus prepared by or on behalf of us or to which we have referred you. This prospectus, any applicable supplement to this prospectus or any related free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor do this prospectus, any applicable supplement to this prospectus or any related free writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction.
You should not assume that the information contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference, even though this prospectus, any applicable prospectus supplement or any related free writing prospectus is delivered, or securities are sold, on a later date.
This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the heading “Where You Can Find More Information.
 
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SUMMARY
This summary highlights selected information from this prospectus and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, including the risks of investing in our securities discussed under the heading “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.
Unless the context requires otherwise, references in this prospectus to the “Company,” “Tocagen,” “we,” “us” and “our” refer to Tocagen Inc.
Company Overview
We are a clinical-stage, cancer-selective gene therapy company focused on developing first-in-class, broadly-applicable product candidates designed to activate a patient’s immune system against their own cancer from within. Our cancer-selective gene therapy platform is built on retroviral replicating vectors, or RRVs, which are designed to selectively deliver therapeutic genes into the DNA of cancer cells. Our gene therapy approach is designed to fight cancer through immunotherapeutic mechanisms of action without the autoimmune toxicities commonly experienced with other immunotherapies. Our founding vision is “No One Should Die Of Cancer” because we believe the immune system can be safely activated to fight the patient’s cancer.
We are developing our lead product candidate, Toca 511 (vocimagene amiretrorepvec) & Toca FC (extended-release flucytosine), initially for the treatment of recurrent high grade glioma, or HGG, a brain cancer with limited treatment options, low survival rates and, therefore, a significant unmet medical need. We are conducting a randomized, controlled Phase 3 clinical trial of Toca 511 & Toca FC in patients with recurrent HGG, or the Toca 5 trial, which is designed to serve as a registrational trial. In February 2017, the U.S. Food and Drug Administration, or FDA, granted Toca 511 & Toca FC Breakthrough Therapy Designation for the treatment of patients with recurrent HGG and in June 2017 the European Medicines Agency, or EMA, granted Toca 511 Priority Medicines, or PRIME, Designation for the treatment of patients with glioma. Breakthrough Therapy Designation indicates that preliminary clinical evidence demonstrates the drug may have substantial improvement on one or more clinically significant endpoints over available therapy. PRIME Designation indicates that there is a potential to benefit patients with unmet medical needs based on early clinical data. We also have Fast Track Designation (which may lead to expedited regulatory review of new products that treat serious diseases or conditions and demonstrate the potential to address an unmet medical need) from the FDA for Toca 511 & Toca FC for the treatment of recurrent HGG. We also received Orphan-Drug Designation from the FDA for the treatment of HGG. Orphan-Drug Designation is a designation for a product that treats a rare disease or condition and which, if the product receives the first FDA approval for that disease or condition, may result in a period of regulatory exclusivity, subject to some exceptions. The Committee for Orphan Medicinal Products of the EMA has designated both flucytosine and vocimagene amiretrorepvec as orphan medicinal products indicated for the treatment of glioma. The EMA provides several benefits to drug developers for developing drugs for orphan diseases.
We have conducted three ascending dose Phase 1 clinical trials involving 127 recurrent HGG patients. In these trials, we investigated three modes of Toca 511 delivery: injection into the cavity wall after surgical resection of the recurred tumor (n=56), direct intratumoral injection without resection (n=54), and intravenous administration followed, approximately one to two weeks later, by resection with further local vector delivery at the time of resection (n=17). Administration of Toca 511 was followed with cycles of Toca FC. In these trials, we observed potential benefits, including durable objective responses, extended overall survival compared to
 
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historical controls and a favorable safety profile. We did not reach a dose-limiting toxicity in any of these trials. Based on these Phase 1 clinical trial results, we are conducting a Phase 3 clinical trial, called the Toca 5 trial, which is designed to serve as a potential registrational trial in patients with first or second recurrent HGG undergoing resection.
As of the data cutoff of December 2017, of the 56 patients enrolled in the ascending-dose resection injection Phase 1 trial, 53 were efficacy evaluable and of those, six patients had a complete response, or CR, and remain in response. All six CR’s were in the higher dose cohorts of the trial. Five of these patients with a CR were within a subset of 23 patients that mirrors the entry criteria, clinical setting and dosing for patients in the Toca 5 trial. Responses were assessed by independent radiology review of magnetic resonance imaging brain scans. Median duration of response had not been reached after a median follow-up of 36.5 months (range: 9.2 to 44.9 months) which compares favorably to a range of durable responses of 2.79 to 9.62 months in a clinical trial of a drug used as standard of care for recurrent HGG. An association between durable response and overall survival is suggested as all responders remain alive following study entry (range: 38.0 to 57.5 months). As of the data cutoff of December 2017, the subset of 23 patients in our Phase 1 resection injection trial that mirrors the Toca 5 patient population (similar entry criteria, clinical setting and dosing) had a median survival of 14.4 months, with an approximately six-month improvement in median overall survival relative to results from clinical trials of drugs used as standard of care for recurrent HGG. In addition:
 
 	•	 	Five of 23 patients had a durable CR, bringing the durable response rate (objective responses lasting at least 24 weeks) to 21.7%.	
 
 	•	 	Median duration of response had not been reached after a median follow up of 37.4 months (range: 16.8 to 44.9 months).	
 
 	•	 	Stable disease (lasting at least eight weeks) was observed in five additional patients, bringing the clinical benefit rate to 43.5% (10/23 patients).	
 
 	•	 	Landmark overall survival, or OS, rates at two and three years (OS24, OS36) was 34.8% and 26.1%, respectively.	
Increases in immunologic activity during treatment were observed with Toca 511 & Toca FC treatment, including elevations of replicating CD4 (often referred to as “helper” T cells) and CD8 (often referred to as “killer” T cells) T cells in the blood, for patients in some cohorts in the resection injection Phase 1 trial.
Based on our findings in preclinical studies and clinical trials to date, we believe Toca 511 & Toca FC is a promising candidate for use in newly diagnosed HGG patients in combination with surgery, radiation and chemotherapy. Therefore, we plan to advance clinical development to evaluate safety and efficacy in this setting with Toca 511 & Toca FC being delivered in conjunction with surgery, radiation and temozolomide.
Based on preclinical data, we believe Toca 511 & Toca FC may also have therapeutic benefit in multiple other solid tumor cancers. Furthermore, in our completed Phase 1 intravenous clinical trial of Toca 511 for the treatment of recurrent HGG, Toca 511 crossed the blood brain barrier and was detected in brain tumors. We therefore initiated a Phase 1b clinical trial, or the Toca 6 trial, in July 2016 of intravenous treatment of advanced cancers that include colorectal, pancreatic, breast, and lung cancers, all of which can spread to the brain and other organs. In the Phase 1b trial, Toca 511 will be administered by intravenous injection followed at 8-11 days later by biopsy then local delivery. In our Toca 6 trial we plan to evaluate safety, presence of Toca 511 genes in tumors, immunologic activity in the blood and tumor such as changes in CD4 and CD8 T cells and clinical activity such as objective tumor response and clinical benefit. We have observed Toca 511 genes and proteins in tumor biopsies following Toca 511 intravenous infusions.
Our RRV platform is versatile and we believe it has the potential to deliver a wide variety of genes selectively to cancer cells. Our first RRV-based immunotherapy product candidate, Toca 511 & Toca FC, is designed to replicate without cell lysis then directly kill cancer and immune suppressive myeloid cells activating
 
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the immune system against cancer through a combination of mechanisms. In addition, we are developing other RRVs to selectively deliver genes to cancer cells against validated immunotherapy targets, such as the checkpoint protein PD-L1. We generated preclinical data supporting the potential anti-cancer benefits of an RRV delivering a gene against PD-L1. In 2018, we plan to initiate IND-enabling studies of our anti-PD-L1 RRV product candidate.
Cancer is the second leading cause of mortality in the United States and accounts for nearly one in four deaths. Early cancer treatments relied on relatively non-specific and highly toxic small molecule chemotherapies. Over the last 20 years, a new paradigm of cancer research and treatment has emerged that is focused on more targeted therapies. Most recently this has included the emergence of immunotherapies that can stimulate a patient’s immune system to slow the growth and the spread of, and ideally, eliminate cancer cells. These therapies have shown the potential to provide dramatic efficacy and to extend survival for cancer patients even in cases in which conventional therapies, such as surgery, chemotherapy and radiotherapy, have already been used. In 2013, Science magazine named cancer immunotherapy as the biggest breakthrough of the year. With this breakthrough, global pharmaceutical companies as well as a large number of emerging companies are researching and developing new cancer immunotherapy treatments.
Despite these advancements, many current immunotherapies, such as checkpoint inhibitors, chimeric antigen receptor and T cell receptor T cells, are limited by their autoimmune and other side effects. Combination treatments are common in cancer, but combinations of immune mediated treatments with systemic cytotoxic chemotherapy may be challenging as chemotherapy is often damaging to the immune system. Thus, immunotherapies effective enough to be able to displace systemic chemotherapy are needed. The utility of oncolytic viruses alone as immunotherapy has been challenged by lack of specificity to tumor cells, injury to healthy tissues, lack of targeting to specific brakes on the immune system, and short-term effect due to effective clearance of the virus. Consequently, there remains a significant need for immunotherapies that are effective as well as safe and tolerable.
In contrast to current immunotherapies, we believe our RRV platform and lead product candidate have the potential to selectively infect cancer cells and subsequently, after 5-FC administration, to stimulate robust and durable anti-cancer immune responses with minimal toxicity. Our RRVs are designed to selectively integrate into the DNA of cancer cells which then serve as factories to produce more of these RRVs by budding. The progeny RRV infect neighboring cancer cells, providing long-term presence of the therapeutic gene or genes. Our novel therapies are designed to break immune tolerance selectively in the tumor microenvironment.
Toca 511 & Toca FC is designed to break immune tolerance through a combination of mechanisms triggered by the conversion of Toca FC into high levels of 5-FU (5-fluorouracil), an anti-cancer agent, directly in tumors. Conversion of Toca FC to 5-FU is catalyzed by the enzyme encoded by the therapeutic gene delivered by Toca 511 into the cancer cell. Toca 511 & Toca FC treatment is designed for cycles of sustained production of high levels of 5-FU directly in tumors, which we believe is important for robust and durable anti-cancer immune activation. Cancer cell death releases damage-associated molecular patterns, pathogen-associated molecular patterns, and tumor-associated antigens, resulting in antigen presentation and activation of T cells. 5-FU is known to kill cancer cells and immune cells when used systemically. When 5-FU is present locally, it kills immune-suppressive myeloid cells in the tumor micro-environment while leaving systemic immune activity clinically intact. The local immune-suppressive myeloid cells include myeloid-derived suppressor cells, or MDSCs, as well as tumor associated macrophages, or TAMs, which are white blood cells recruited and retained by the tumor that contribute to the suppression of normal immune activity against cancer cells. TAMs and MDSCs suppress the number and activity of CD4 and CD8 T cells and work with the lymphocyte-derived suppressor T cells called regulatory T cells. MDSC and TAM destruction by 5-FU is designed to contribute to immune activation against the tumor-associated antigens. We believe the persistence of the therapeutic gene in the cancer cells has allowed for multiple cycles of Toca FC treatment in our trials, which may result in additional killing of cancer cells and immunosuppressive myeloid cells, leading to enhancement of the strength and durability of the immune response with each successive cycle of Toca FC treatment. Also, in a trial with multiple
 
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Toca 511 intravenous infusions followed by resection, we observed increased Toca 511 in the tumor compared to single day infusion.
We have entered into selected partnerships for the development and commercialization of our technology and products. We have entered into a license agreement with Beijing Apollo Venus Biomedical Technology Limited and ApolloBio Corp., or collectively ApolloBio, pursuant to which we granted to ApolloBio an exclusive license to develop and commercialize Toca 511 & Toca FC within the greater China region, including mainland China, Hong Kong, Macao and Taiwan. Under the license agreement, we are eligible to receive up to $127 million in upfront payment, development and commercial milestones, plus additional double-digit tiered sales royalties. The upfront and near-term development milestone payments total up to $20 million. We have licensed rights to, and collaborate with, Siemens Healthcare Diagnostics Inc. to develop diagnostics related to the clinical development and future commercialization of Toca 511 & Toca FC. We have intellectual property protection in major markets worldwide, including 76 issued and granted patents and 72 patent applications (foreign and domestic) on our technology platform and novel product candidates, which we believe will maintain coverage from issued patents until approximately 2030. Since inception in 2007, we have funded our operations primarily through the sales of our equity securities from which we received $230.2 million in net proceeds.
Corporate Information
We were incorporated in Delaware in August 2007. Our principal executive offices are located at 3030 Bunker Hill Street, Suite 230, San Diego, California 92109. Our telephone number is (858) 412-8400. Our corporate website address is www.tocagen.com. Information contained on or accessible through our website is not a part of this prospectus, and the inclusion of our website address in this prospectus is an inactive textual reference only.
This prospectus contains references to our trademarks and to trademarks belonging to other entities. Solely for convenience, trademarks and trade names referred to in this prospectus, including logos, artwork and other visual displays, may appear without the ® or TM symbols, but such references are not intended to indicate, in any way, that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend our use or display of other companies’ trade names or trademarks to imply a relationship with, or endorsement or sponsorship of us by, any other companies.
The Securities We May Offer
We may offer shares of our common stock and preferred stock, various series of debt securities and warrants to purchase any of such securities, up to a total aggregate offering price of $100,000,000 from time to time in one or more offerings under this prospectus, together with any applicable prospectus supplement and any related free writing prospectus, at prices and on terms to be determined by market conditions at the time of the relevant offering. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:
 
 	•	 	designation or classification;	
 
 	•	 	aggregate principal amount or aggregate offering price;	
 
 	•	 	maturity, if applicable;	
 
 	•	 	original issue discount, if any;	
 
 	•	 	rates and times of payment of interest or dividends, if any;	
 
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 	•	 	redemption, conversion, exchange or sinking fund terms, if any;	
 
 	•	 	conversion or exchange prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in the conversion or exchange prices or rates and in the securities or other property receivable upon conversion or exchange;	
 
 	•	 	ranking, if applicable;	
 
 	•	 	restrictive covenants, if any;	
 
 	•	 	voting or other rights, if any; and	
 
 	•	 	important U.S. federal income tax considerations.	
The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in documents we have incorporated by reference. However, no prospectus supplement or free writing prospectus will offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.
This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.
We may sell the securities directly to investors or through underwriters, dealers or agents. We, and our underwriters or agents, reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities through underwriters or agents, we will include in the applicable prospectus supplement:
 
 	•	 	the names of those underwriters or agents;	
 
 	•	 	applicable fees, discounts and commissions to be paid to them;	
 
 	•	 	details regarding over-allotment options, if any; and	
 
 	•	 	the estimated net proceeds to us.	
Common Stock. We may issue shares of our common stock from time to time. Holders of our common stock are entitled to one vote per share for the election of directors and on all other matters that require stockholder approval. Subject to any preferential rights of any then outstanding preferred stock, in the event of our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in the assets remaining after payment of liabilities and the liquidation preferences of any then outstanding preferred stock. Our common stock does not carry any preemptive rights enabling a holder to subscribe for, or receive shares of, any class of our common stock or any other securities convertible into shares of any class of our common stock, or any redemption rights.
Preferred Stock. We may issue shares of our preferred stock from time to time, in one or more series. Under our amended and restated certificate of incorporation, our board of directors has the authority, without further action by stockholders, to designate up to 10,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges, qualifications and restrictions granted to or imposed upon the preferred stock, including dividend rights, conversion rights, voting rights, rights and terms of redemption, liquidation preference and sinking fund terms, any or all of which may be greater than the rights of the common stock. To date, none of the 10,000,000 authorized shares of preferred stock have been designated by our board of directors. Convertible preferred stock will be convertible into our common stock or exchangeable for our other securities. Conversion may be mandatory or at the option of the holders of our preferred stock and would be at prescribed conversion rates.
We will fix the rights, preferences, privileges, qualifications and restrictions of the preferred stock of each series that we sell under this prospectus and applicable prospectus supplements in the certificate of designation
 
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relating to that series. We will incorporate by reference into the registration statement of which this prospectus is a part the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of the related series of preferred stock. We urge you, however, to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to the series of preferred stock being offered, as well as the complete certificate of designation that contains the terms of the applicable series of preferred stock.
Debt Securities. We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. The senior debt securities will rank equally with any other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment, to the extent and in the manner described in the instrument governing the debt, to all of our senior indebtedness. Convertible debt securities will be convertible into our common stock or preferred stock. Conversion may be mandatory or at the holder’s option and would be at prescribed conversion rates.
The debt securities will be issued under one or more documents called indentures, which are contracts between us and a national banking association or other eligible party, as trustee. In this prospectus, we have summarized certain general features of the debt securities. We urge you, however, to read the applicable prospectus supplement (and any free writing prospectus that we may authorize to be provided to you) related to the series of debt securities being offered, as well as the complete indentures that contain the terms of the debt securities. A form of indenture has been filed as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.
Warrants. We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities. In this prospectus, we have summarized certain general features of the warrants. We urge you, however, to read the applicable prospectus supplement (and any free writing prospectus that we may authorize to be provided to you) related to the particular series of warrants being offered, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants. Forms of the warrant agreements and forms of warrant certificates containing the terms of the warrants being offered have been filed as exhibits to the registration statement of which this prospectus is a part, and supplemental warrant agreements and forms of warrant certificates will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.
We will evidence each series of warrants by warrant certificates that we will issue. Warrants may be issued under an applicable warrant agreement that we enter into with a warrant agent. We will indicate the name and address of the warrant agent, if applicable, in the prospectus supplement relating to the particular series of warrants being offered.
RISK FACTORS
Investing in our securities involves a high degree of risk. You should carefully review the risks and uncertainties described under the heading “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in our Annual Report on Form 10-K for the year ended December 31, 2017, as updated by our annual, quarterly and other reports and documents that are incorporated by reference into this prospectus, before deciding whether to purchase any of the securities being registered pursuant to the registration statement of which this prospectus is a part. Each of the risk factors could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities, and the occurrence of any of these risks might cause you to lose all or part of your
 
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investment. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations.
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
This prospectus, each prospectus supplement and the information incorporated by reference in this prospectus and each prospectus supplement contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act of 1934, as amended, or the Exchange Act, that involve a number of risks and uncertainties. Although our forward-looking statements reflect the good faith judgment of our management, these statements can only be based on facts and factors currently known by us. Consequently, these forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from results and outcomes discussed in the forward-looking statements.
Forward-looking statements can be identified by the use of forward-looking words such as “believes,” “expects,” “hopes,” “may,” “will,” “plan,” “intends,” “estimates,” “could,” “should,” “would,” “continue,” “seeks,” “pro forma,” or “anticipates,” or other similar words (including their use in the negative), or by discussions of future matters such as the development of new products, technology enhancements, possible collaborations and other statements that are not historical. These statements include but are not limited to statements under the captions “Business,” “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and in other sections incorporated by reference from our Annual Report on Form 10-K and Quarterly Reports on Form 10-Q, as applicable, as well as our other filings with the SEC. You should be aware that the occurrence of any of the events discussed under the heading “Risk Factors” in any applicable prospectus supplement and any documents incorporated by reference herein or therein could substantially harm our business, operating results and financial condition and that if any of these events occurs, it could adversely affect the value of an investment in our securities.
The cautionary statements made in this prospectus are intended to be applicable to all related forward-looking statements wherever they may appear in this prospectus or in any prospectus supplement or any documents incorporated by reference herein or therein. We urge you not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. Except as required by law, we assume no obligation to update our forward-looking statements, even if new information becomes available in the future.
 
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RATIO OF EARNINGS TO FIXED CHARGES
The following table sets forth our ratio of earnings to fixed charges and the ratio of our combined fixed charges and preferred dividends to earnings for each of the periods indicated. The following table is qualified by the more detailed information appearing in the computation table set forth in Exhibit 12.1 to the registration statement of which this prospectus is part and the historical financial statements, including the notes to those financial statements, incorporated by reference in this prospectus. We have paid no dividends on preferred shares during the periods indicated. Therefore, the ratios of earnings to combined fixed charges and preferred dividends are the same as the ratio of earnings to fixed charges.

 	  	Year Ended December 31,	 	  	Three Months
Ended
March 31,	 	
 	  	2015	 	  	2016	 	  	2017	 	  	2018	 	
 	  	 	 	  	(in thousands)	 	
Ratio of earnings to fixed charges	  	 	N/A	 	  	 	N/A	 	  	 	N/A	 	  	 	N/A	 	
Ratio of earnings to combined fixed charges and preferred stock dividends	  	 	N/A	 	  	 	N/A	 	  	 	N/A	 	  	 	N/A	 	
Deficiency of earnings available to cover fixed charges	  	$	(23,056	) 	  	$	(33,478	) 	  	$	(38,929	) 	  	$	(12,880	) 	
Deficiency of earnings available to cover combined fixed charges and preferred stock dividends	  	$	(23,056	) 	  	$	(33,478	) 	  	$	(38,929	) 	  	$	(12,880	) 	
For purposes of computing the ratio of earnings to fixed charges and the ratio of our combined fixed charges and preferred stock dividends to earnings, earnings consist of income (loss) from continuing operations before income taxes plus fixed charges. Fixed charges consist of interest expense on indebtedness and an estimate of the interest within rental expense.
We did not record earnings for any of the years ended December 31, 2015, 2016, and 2017 or for the three months ended March 31, 2018. Accordingly, our earnings were insufficient to cover fixed charges for such periods and we are unable to disclose a ratio of earnings to fixed charges for such periods.
USE OF PROCEEDS
We will retain broad discretion over the use of the net proceeds from the sale of the securities offered hereby. Except as described in any prospectus supplement or any related free writing prospectus that we may authorize to be provided to you, we currently intend to use the net proceeds from the sale of the securities offered hereby for general corporate purposes, which may include research and development, capital expenditures, working capital and general and administrative expenses. We may also use a portion of the net proceeds to acquire or invest in businesses, products and technologies that are complementary to our own, although we have no current plans, commitments or agreements with respect to any acquisitions as of the date of this prospectus. We will set forth in the applicable prospectus supplement or free writing prospectus our intended use for the net proceeds received from the sale of any securities sold pursuant to the prospectus supplement or free writing prospectus. Pending these uses, we intend to invest the net proceeds in short- and intermediate-term, investment-grade, interest-bearing securities.
DESCRIPTION OF CAPITAL STOCK
As of the date of this prospectus, our amended and restated certificate of incorporation authorizes us to issue 200,000,000 shares of common stock, par value $0.001 per share and 10,000,000 shares of preferred stock, par value $0.001 per share. As of May 22, 2018, 19,912,983 shares of common stock were outstanding and no shares of preferred stock were outstanding. All of our authorized preferred stock is undesignated.
 
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The following is a summary of the rights of our common and preferred stockholders, of some of the provisions of our amended and restated certificate of incorporation and amended and restated bylaws and of the Delaware General Corporation Law, or DGCL. This summary is not complete. For more detailed information, please see our amended and restated certificate of incorporation and amended and restated bylaws, which are filed as exhibits to the registration statement of which this prospectus is a part, as well as the relevant provisions of the DGCL.
Common Stock
Voting. Our common stock is entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, including the election of directors, and does not have cumulative voting rights. Accordingly, the holders of a majority of the shares of our common stock entitled to vote in any election of directors can elect all of the directors standing for election.
Dividends. Subject to preferences that may be applicable to any then-outstanding preferred stock, the holders of common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds.
Liquidation. In the event of our liquidation, dissolution or winding-up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.
Rights and Preferences. Holders of our common stock have no preemptive, conversion or subscription rights, and there are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.
Preferred Stock
Under our amended and restated certificate of incorporation, our board of directors has the authority, without further action by stockholders, to designate up to 10,000,000 shares of preferred stock in one or more series and to fix or alter, from time to time, the designations, powers and rights of each series of preferred stock and the qualifications, limitations or restrictions of any series of preferred stock, including dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions), redemption price or prices, and the liquidation preference of any wholly unissued series of preferred stock, any or all of which may be greater than the rights of the common stock, and to establish the number of shares constituting any such series. To date, none of the 10,000,000 authorized shares of preferred stock have been designated by our board of directors.
Our board of directors will fix the rights, preferences, privileges, qualifications and restrictions of the preferred stock of each series that we sell under this prospectus and any applicable prospectus supplements in the certificate of designation relating to each such series. We will incorporate by reference as an exhibit to the registration statement of which this prospectus is a part or as an exhibit to one or more Current Reports on Form 8-K, the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of the related series of preferred stock. This description will include:
 
 	•	 	the title and stated value;	
 
 	•	 	the number of shares we are offering;	
 
 	•	 	the liquidation preference per share;	
 
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 	•	 	the purchase price per share;	
 
 	•	 	the dividend rate per share, dividend period, payment date or dates and method of calculation for dividends;	
 
 	•	 	whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;	
 
 	•	 	our right, if any, to defer payment of dividends and the maximum length of any such deferral period;	
 
 	•	 	the procedures for any auction and remarketing, if any;	
 
 	•	 	the provisions for a sinking fund, if any;	
 
 	•	 	the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;	
 
 	•	 	any listing of the preferred stock on any securities exchange or market;	
 
 	•	 	whether the preferred stock will be convertible into our common stock or other securities of ours, including warrants, and, if applicable, the conversion price, or how it will be calculated, and under what circumstances and the mechanism by which it may be adjusted, and the conversion period;	
 
 	•	 	whether the preferred stock will be exchangeable into debt securities or other securities of ours, and, if applicable, the exchange price, or how it will be calculated, and under what circumstances it may be adjusted, and the exchange period;	
 
 	•	 	voting rights, if any;	
 
 	•	 	preemptive rights, if any;	
 
 	•	 	restrictions on transfer, sale or other assignment, if any;	
 
 	•	 	whether interests in the preferred stock will be represented by depositary shares;	
 
 	•	 	a discussion of any material or special U.S. federal income tax considerations applicable to the preferred stock;	
 
 	•	 	the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;	
 
 	•	 	any limitations on issuances of any class or series of preferred stock ranking senior to or on parity with the series of preferred stock being issued as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and	
 
 	•	 	any other specific terms, rights, preferences, privileges, qualifications or limitations of, or restrictions on the preferred stock.	
If we issue and sell shares of preferred stock pursuant to this prospectus, together with any applicable prospectus supplement or free writing prospectus, the shares will be fully paid and nonassessable.
The laws of the state of Delaware, the state of our incorporation, provide that the holders of preferred stock will have the right to vote separately, as a class, on any proposal involving fundamental changes in the rights of holders of such preferred stock. This right is in addition to any voting rights that may be provided for in the applicable certificate of designation.
The issuance of preferred stock could adversely affect the voting power, conversion or other rights of holders of common stock and reduce the likelihood that common stockholders will receive dividend payments and payments upon liquidation. Preferred stock could be issued quickly with terms designed to delay, deter or prevent a change in control of our company or make removal of management more difficult. Additionally, the issuance of preferred stock may have the effect of decreasing the market price of our common stock.
 
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Anti-Takeover Effects of Provisions of Our Amended and Restated Certificate of Incorporation, Our Bylaws and Delaware Law
Delaware Anti-Takeover Law
We are subject to Section 203 of the DGCL, which generally prohibits a public Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:
 
 	•	 	prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;	
 
 	•	 	the interested stockholder owned at least 85% of the voting stock of the corporation outstanding upon consummation of the transaction, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or	
 
 	•	 	on or subsequent to the consummation of the transaction, the business combination is approved by the board and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock which is not owned by the interested stockholder.	
Section 203 of the DGCL defines a business combination to include:
 
 	•	 	any merger or consolidation involving the corporation and the interested stockholder;	
 
 	•	 	any sale, transfer, pledge or other disposition involving the interested stockholder of 10% or more of the assets of the corporation;	
 
 	•	 	subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder;	
 
 	•	 	subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder; and	
 
 	•	 	the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.	
In general, Section 203 of the DGCL defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.
Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws
Provisions of our amended and restated certificate of incorporation and amended and restated bylaws, may delay or discourage transactions involving an actual or potential change in our control or change in our management, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. Therefore, these provisions could adversely affect the price of our common stock. Among other things, our amended and restated certificate of incorporation and amended and restated bylaws:
 
 	•	 	permit our board of directors to issue up to 10,000,000 shares of preferred stock, with any rights, preferences and privileges as they may designate;	
 
 	•	 	provide that the authorized number of directors may be changed only by resolution adopted by a majority of the board of directors;	
 
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 	•	 	provide that the board of directors or any individual director may only be removed with cause and the affirmative vote of the holders of at least 66 2/3% of the voting power of all of our then outstanding common stock;	
 
 	•	 	provide that all vacancies, including newly created directorships, may, except as otherwise required by law or subject to the rights of holders of preferred stock as designated from time to time, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;	
 
 	•	 	divide our board of directors into three classes;	
 
 	•	 	require that any action to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders and not be taken by written consent or electronic transmission;	
 
 	•	 	provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide notice in writing in a timely manner and also specify requirements as to the form and content of a stockholder’s notice;	
 
 	•	 	do not provide for cumulative voting rights (therefore allowing the holders of a majority of the shares of common stock entitled to vote in any election of directors to elect all of the directors standing for election, if they should so choose);	
 
 	•	 	provide that special meetings of our stockholders may be called only by the chairman of the board, our Chief Executive Officer or by the board of directors pursuant to a resolution adopted by a majority of the total number of authorized directors (whether or not there exists any vacancies); and	
 
 	•	 	provide that the Court of Chancery of the State of Delaware will be the sole and exclusive forum for (1) any derivative action or proceeding brought on our behalf, (2) any action asserting a claim of breach of a fiduciary duty owed by any of our directors or officers to us or our stockholders, (3) any action asserting a claim against the us arising pursuant to any provision of the DGCL or our certificate of incorporation or bylaws, or (4) any action asserting a claim against us governed by the internal affairs doctrine.	
The amendment of any of these provisions, with the exception of the ability of our board of directors to issue shares of preferred stock and designate any rights, preferences and privileges thereto, would require the affirmative vote of the holders of at least 66 2/3% of the voting power of all of our then outstanding common stock.
Transfer Agent and Registrar
The transfer agent and registrar for our common stock is Computershare Trust Company, N.A. The transfer agent and registrar’s address is 250 Royall Street, Canton, Massachusetts 02021. The transfer agent for any series of preferred stock that we may offer under this prospectus will be named and described in the prospectus supplement for that series.
Listing on the Nasdaq Global Select Market
Our common stock is listed on the Nasdaq Global Select Market under the symbol “TOCA”.
DESCRIPTION OF DEBT SECURITIES
We may issue debt securities from time to time, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any debt securities that we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt
 
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securities offered under a prospectus supplement may differ from the terms described below. Unless the context requires otherwise, whenever we refer to the indenture, we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.
We will issue the debt securities under the indenture that we will enter into with the trustee named in the indenture. The indenture will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We have filed the form of indenture as an exhibit to the registration statement of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.
The following summary of material provisions of the debt securities and the indenture is subject to, and qualified in its entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indenture that contains the terms of the debt securities.
General
The indenture does not limit the amount of debt securities that we may issue. It provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit that we may designate. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to give holders of any debt securities protection against changes in our operations, financial condition or transactions involving us.
We may issue the debt securities issued under the indenture as “discount securities,” which means they may be sold at a discount below their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may be issued with “original issue discount,” or OID, for U.S. federal income tax purposes because of interest payment and other characteristics or terms of the debt securities. Material U.S. federal income tax considerations applicable to debt securities issued with OID will be described in more detail in any applicable prospectus supplement.
We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:
 
 	•	 	the title of the series of debt securities;	
 
 	•	 	any limit upon the aggregate principal amount that may be issued;	
 
 	•	 	the maturity date or dates;	
 
 	•	 	the form of the debt securities of the series;	
 
 	•	 	the applicability of any guarantees;	
 
 	•	 	whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;	
 
 	•	 	whether the debt securities rank as senior debt, senior subordinated debt, subordinated debt or any combination thereof, and the terms of any subordination;	
 
 	•	 	if the price (expressed as a percentage of the aggregate principal amount thereof) at which such debt securities will be issued is a price other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or if applicable, the portion of the principal amount of such debt securities that is convertible into another security or the method by which any such portion shall be determined;	
 
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 	•	 	the interest rate or rates, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;	
 
 	•	 	our right, if any, to defer payment of interest and the maximum length of any such deferral period;	
 
 	•	 	if applicable, the date or dates after which, or the period or periods during which, and the price or prices at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;	
 
 	•	 	the date or dates, if any, on which, and the price or prices at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;	
 
 	•	 	the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;	
 
 	•	 	any and all terms, if applicable, relating to any auction or remarketing of the debt securities of that series and any security for our obligations with respect to such debt securities and any other terms which may be advisable in connection with the marketing of debt securities of that series;	
 
 	•	 	whether the debt securities of the series shall be issued in whole or in part in the form of a global security or securities; the terms and conditions, if any, upon which such global security or securities may be exchanged in whole or in part for other individual securities; and the depositary for such global security or securities;	
 
 	•	 	if applicable, the provisions relating to conversion or exchange of any debt securities of the series and the terms and conditions upon which such debt securities will be so convertible or exchangeable, including the conversion or exchange price, as applicable, or how it will be calculated and may be adjusted, any mandatory or optional (at our option or the holders’ option) conversion or exchange features, the applicable conversion or exchange period and the manner of settlement for any conversion or exchange;	
 
 	•	 	if other than the full principal amount thereof, the portion of the principal amount of debt securities of the series which shall be payable upon declaration of acceleration of the maturity thereof;	
 
 	•	 	additions to or changes in the covenants applicable to the particular debt securities being issued, including, among others, the consolidation, merger or sale covenant;	
 
 	•	 	additions to or changes in the events of default with respect to the securities and any change in the right of the trustee or the holders to declare the principal, premium, if any, and interest, if any, with respect to such securities to be due and payable;	
 
 	•	 	additions to or changes in or deletions of the provisions relating to covenant defeasance and legal defeasance;	
 
 	•	 	additions to or changes in the provisions relating to satisfaction and discharge of the indenture;	
 
 	•	 	additions to or changes in the provisions relating to the modification of the indenture both with and without the consent of holders of debt securities issued under the indenture;	
 
 	•	 	the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars;	
 
 	•	 	whether interest will be payable in cash or additional debt securities at our or the holders’ option and the terms and conditions upon which the election may be made;	
 
 	•	 	the terms and conditions, if any, upon which we will pay amounts in addition to the stated interest, premium, if any, and principal amounts of the debt securities of the series to any holder that is not a “United States person” for federal tax purposes;	
 
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 	•	 	any restrictions on transfer, sale or assignment of the debt securities of the series; and	
 
 	•	 	any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, any other additions or changes in the provisions of the indenture, and any terms that may be required by us or advisable under applicable laws or regulations.	
Conversion or Exchange Rights
We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to settlement upon conversion or exchange and whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.
Consolidation, Merger or Sale
Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indenture will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of our assets as an entirety or substantially as an entirety. However, any successor to or acquirer of such assets (other than a subsidiary of ours) must assume all of our obligations under the indenture or the debt securities, as appropriate.
Events of Default under the Indenture
Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indenture with respect to any series of debt securities that we may issue:
 
 	•	 	if we fail to pay any installment of interest on any series of debt securities, as and when the same shall become due and payable, and such default continues for a period of 90 days; provided, however, that a valid extension of an interest payment period by us in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of interest for this purpose;	
 
 	•	 	if we fail to pay the principal of, or premium, if any, on any series of debt securities as and when the same shall become due and payable whether at maturity, upon redemption, by declaration or otherwise, or in any payment required by any sinking or analogous fund established with respect to such series; provided, however, that a valid extension of the maturity of such debt securities in accordance with the terms of any indenture supplemental thereto shall not constitute a default in the payment of principal or premium, if any;	
 
 	•	 	if we fail to observe or perform any other covenant or agreement contained in the debt securities or the indenture, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive written notice of such failure, requiring the same to be remedied and stating that such is a notice of default thereunder, from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and	
 
 	•	 	if specified events of bankruptcy, insolvency or reorganization occur.	
If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.
 
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The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.
Subject to the terms of the indenture, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:
 
 	•	 	the direction so given by the holder is not in conflict with any law or the applicable indenture; and	
 
 	•	 	subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.	
A holder of the debt securities of any series will have the right to institute a proceeding under the indenture or to appoint a receiver or trustee, or to seek other remedies only if:
 
 	•	 	the holder has given written notice to the trustee of a continuing event of default with respect to that series;	
 
 	•	 	the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request;	
 
 	•	 	such holders have offered to the trustee indemnity satisfactory to it against the costs, expenses and liabilities to be incurred by the trustee in compliance with the request; and	
 
 	•	 	the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.	
These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.
We will periodically file statements with the trustee regarding our compliance with specified covenants in the indenture.
Modification of Indenture; Waiver
We and the trustee may change an indenture without the consent of any holders with respect to specific matters:
 
 	•	 	to cure any ambiguity, defect or inconsistency in the indenture or in the debt securities of any series;	
 
 	•	 	to comply with the provisions described above under “Description of Debt Securities–Consolidation, Merger or Sale;”	
 
 	•	 	to provide for uncertificated debt securities in addition to or in place of certificated debt securities;	
 
 	•	 	to add to our covenants, restrictions, conditions or provisions such new covenants, restrictions, conditions or provisions for the benefit of the holders of all or any series of debt securities, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred upon us in the indenture;	
 
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 	•	 	to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;	
 
 	•	 	to make any change that does not adversely affect the interests of any holder of debt securities of any series in any material respect;	
 
 	•	 	to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided above under “Description of Debt Securities–General” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;	
 
 	•	 	to evidence and provide for the acceptance of appointment under any indenture by a successor trustee; or	
 
 	•	 	to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act.	
In addition, under the indenture, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:
 
 	•	 	extending the fixed maturity of any debt securities of any series;	
 
 	•	 	reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any series of any debt securities; or	
 
 	•	 	reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.	
Discharge
The indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:
 
 	•	 	provide for payment;	
 
 	•	 	register the transfer or exchange of debt securities of the series;	
 
 	•	 	replace stolen, lost or mutilated debt securities of the series;	
 
 	•	 	pay principal of and premium and interest on any debt securities of the series;	
 
 	•	 	maintain paying agencies;	
 
 	•	 	hold monies for payment in trust;	
 
 	•	 	recover excess money held by the trustee;	
 
 	•	 	compensate and indemnify the trustee; and	
 
 	•	 	appoint any successor trustee.	
In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.
Form, Exchange and Transfer
We will issue the debt securities of each series only in fully registered form without coupons and, unless we provide otherwise in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple
 
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thereof. The indenture provides that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company, or DTC, or another depositary named by us and identified in the applicable prospectus supplement with respect to that series. To the extent the debt securities of a series are issued in global form and as book-entry, a description of terms relating to any book-entry securities will be set forth in the applicable prospectus supplement.
At the option of the holder, subject to the terms of the indenture and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.
Subject to the terms of the indenture and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.
We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.
If we elect to redeem the debt securities of any series, we will not be required to:
 
 	•	 	issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or	
 
 	•	 	register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.	
Information Concerning the Trustee
The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indenture at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.
Payment and Paying Agents
Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.
We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire
 
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transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.
All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.
Governing Law
The indenture and the debt securities will be governed by and construed in accordance with the internal laws of the State of New York, except to the extent that the Trust Indenture Act of 1939 is applicable.
DESCRIPTION OF WARRANTS
The following description, together with the additional information we may include in any applicable prospectus supplements and free writing prospectuses, summarizes the material terms and provisions of the warrants that we may offer under this prospectus, which may consist of warrants to purchase common stock, preferred stock or debt securities and may be issued in one or more series. Warrants may be issued independently or together with common stock, preferred stock or debt securities offered by any prospectus supplement, and may be attached to or separate from those securities. While the terms we have summarized below will apply generally to any warrants that we may offer under this prospectus, we will describe the particular terms of any series of warrants that we may offer in more detail in the applicable prospectus supplement and any applicable free writing prospectus. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.
We have filed forms of the warrant agreements as exhibits to the registration statement of which this prospectus is a part. We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant agreement, if any, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectuses, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.
General
We will describe in the applicable prospectus supplement the terms relating to a series of warrants being offered, including:
 
 	•	 	the title of such securities;	
 
 	•	 	the offering price or prices and aggregate number of warrants offered;	
 
 	•	 	the currency or currencies for which the warrants may be purchased;	
 
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 	•	 	if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;	
 
 	•	 	if applicable, the date on and after which the warrants and the related securities will be separately transferable;	
 
 	•	 	if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;	
 
 	•	 	in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at which, and currency in which, this principal amount of debt securities may be purchased upon such exercise;	
 
 	•	 	in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which, and the currency in which, these shares may be purchased upon such exercise;	
 
 	•	 	the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;	
 
 	•	 	the terms of any rights to redeem or call the warrants;	
 
 	•	 	the terms of any rights to force the exercise of the warrants;	
 
 	•	 	any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;	
 
 	•	 	the dates on which the right to exercise the warrants will commence and expire;	
 
 	•	 	the manner in which the warrant agreements and warrants may be modified;	
 
 	•	 	a discussion of any material or special U.S. federal income tax consequences of holding or exercising the warrants;	
 
 	•	 	the terms of the securities issuable upon exercise of the warrants; and	
 
 	•	 	any other specific terms, preferences, rights or limitations of or restrictions on the warrants.	
Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:
 
 	•	 	in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or	
 
 	•	 	in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.	
Exercise of Warrants
Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.
Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as
 
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provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent in connection with the exercise of the warrant.
Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.
Governing Law
Unless we provide otherwise in the applicable prospectus supplement, the warrants and warrant agreements, and any claim, controversy or dispute arising under or related to the warrants or warrant agreements, will be governed by and construed in accordance with the laws of the State of New York.
Enforceability of Rights by Holders of Warrants
Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.
LEGAL OWNERSHIP OF SECURITIES
We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee or depositary maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names as “indirect holders” of those securities. As we discuss below, indirect holders are not legal holders and investors in securities issued in book-entry form or in street name will be indirect holders.
Book-Entry Holders
We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.
Only the person in whose name a security is registered is recognized as the holder of that security. Global securities will be registered in the name of the depositary or its participants. Consequently, for global securities, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.
 
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As a result, investors in a global security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not legal holders, of the securities.
Street Name Holders
A global security may be terminated in certain situations as described under “-Special Situations When a Global Security Will Be Terminated,” or issue securities that are not issued in global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.
For securities held in street name, we or any applicable trustee or depositary will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we or any such trustee or depositary will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.
Legal Holders
Our obligations, as well as the obligations of any applicable trustee or third party employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.
For example, once we make a payment or give a notice to the legal holder, we have no further responsibility for the payment or notice even if that legal holder is required, under agreements with its participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of an indenture, or for other purposes. In such an event, we would seek approval only from the legal holders, and not the indirect holders, of the securities. Whether and how the legal holders contact the indirect holders is up to the legal holders.
Special Considerations for Indirect Holders
If you hold securities through a bank, broker or other financial institution, either in book-entry form because the securities are represented by one or more global securities or in street name, you should check with your own institution to find out:
 
 	•	 	how it handles securities payments and notices;	
 
 	•	 	whether it imposes fees or charges;	
 
 	•	 	how it would handle a request for the holders’ consent, if ever required;	
 
 	•	 	whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;	
 
 	•	 	how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and	
 
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 	•	 	if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.	
Global Securities
A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.
Each security issued in book-entry form will be represented by a global security that we issue to, deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, the DTC will be the depositary for all securities issued in book-entry form.
A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under “-Special Situations When a Global Security Will Be Terminated.” As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and legal holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a legal holder of the security, but only an indirect holder of a beneficial interest in the global security.
If the prospectus supplement for a particular security indicates that the security will be issued as a global security, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.
Special Considerations for Global Securities
As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.
If securities are issued only as global securities, an investor should be aware of the following:
 
 	•	 	an investor cannot cause the securities to be registered in his or her name, and cannot obtain non-global certificates for his or her interest in the securities, except in the special situations we describe below;	
 
 	•	 	an investor will be an indirect holder and must look to his or her own bank or broker for payments on the securities and protection of his or her legal rights relating to the securities, as we describe above;	
 
 	•	 	an investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form;	
 
 	•	 	an investor may not be able to pledge his or her interest in the global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective;	
 
 	•	 	the depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges and other matters relating to an investor’s interest in the global security;	
 
 	•	 	we and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in the global security, nor will we or any applicable trustee supervise the depositary in any way;	
 
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 	•	 	the depositary may, and we understand that DTC will, require that those who purchase and sell interests in the global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well; and	
 
 	•	 	financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in the global security, may also have their own policies affecting payments, notices and other matters relating to the securities.	
There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.
Special Situations When a Global Security Will Be Terminated
In a few special situations described below, a global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own names, so that they will be direct holders. We have described the rights of holders and street name investors above.
A global security will terminate when the following special situations occur:
 
 	•	 	if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;	
 
 	•	 	if we notify any applicable trustee that we wish to terminate that global security; or	
 
 	•	 	if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.	
The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and neither we nor any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.
PLAN OF DISTRIBUTION
We may sell the securities from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a combination of these methods. We may sell the securities to or through underwriters or dealers, through agents, or directly to one or more purchasers. We may distribute securities from time to time in one or more transactions:
 
 	•	 	at a fixed price or prices, which may be changed;	
 
 	•	 	at market prices prevailing at the time of sale;	
 
 	•	 	at prices related to such prevailing market prices; or	
 
 	•	 	at negotiated prices.	
We may also sell equity securities covered by this registration statement in an “at the market offering” as defined in Rule 415 under the Securities Act. Such offering may be made into an existing trading market for such securities in transactions at other than a fixed price, either:
 
 	•	 	on or through the facilities of the Nasdaq Global Select Market or any other securities exchange or quotation or trading service on which such securities may be listed, quoted or traded at the time of sale; and/or	
 
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 	•	 	to or through a market maker other than on the Nasdaq Global Select Market or such other securities exchanges or quotation or trading services.	
Such at-the-market offerings, if any, may be conducted by underwriters acting as principal or agent.
A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the securities, including, to the extent applicable:
 
 	•	 	the name or names of any underwriters, dealers or agents, if any;	
 
 	•	 	the purchase price of the securities and the proceeds we will receive from the sale;	
 
 	•	 	any over-allotment options under which underwriters may purchase additional securities from us;	
 
 	•	 	any agency fees or underwriting discounts and other items constituting agents’ or underwriters’ compensation;	
 
 	•	 	any public offering price;	
 
 	•	 	any discounts or concessions allowed or reallowed or paid to dealers; and	
 
 	•	 	any securities exchange or market on which the securities may be listed.	
Only underwriters named in the prospectus supplement are underwriters of the securities offered by the prospectus supplement.
If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement. Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may change from time to time. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement, naming the underwriter, the nature of any such relationship.
We may sell securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities, and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.
We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.
We may provide agents and underwriters with indemnification against civil liabilities related to this offering, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to these liabilities. Agents and underwriters may engage in transactions with, or perform services for, us in the ordinary course of business.
Other than common stock, all securities we offer will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities.
 
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Any underwriter may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids. Overallotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. These transactions may be effected on any exchange or over-the-counter market or otherwise.
Any underwriters who are qualified market makers on the Nasdaq Global Select Market may engage in passive market making transactions in the securities on the Nasdaq Global Select Market in accordance with Rule 103 of Regulation M, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.
LEGAL MATTERS
Unless otherwise indicated in the applicable prospectus supplement, certain legal matters in connection with the offering and the validity of the securities offered by this prospectus, and any supplement thereto, has been passed upon by Cooley LLP.
EXPERTS
Ernst & Young LLP, independent registered public accounting firm, has audited our financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2017, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.
WHERE YOU CAN FIND MORE INFORMATION
This prospectus is part of a registration statement we filed with the SEC. This prospectus does not contain all of the information set forth in the registration statement and the exhibits to the registration statement. For further information with respect to us and the securities we are offering under this prospectus, we refer you to the registration statement and the exhibits and schedules filed as a part of the registration statement. Neither we nor any agent, underwriter or dealer has authorized any person to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus is accurate as of any date other than the date on the front page of this prospectus, regardless of the time of delivery of this prospectus or any sale of the securities offered by this prospectus.
We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy the registration statement, as well as any other document filed by us with the SEC, at the SEC’s Public Reference Room at 100 F Street NE, Washington, D.C. 20549. You can also request copies of
 
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these documents by writing to the SEC and paying a fee for the copying cost. You may obtain information on the operation of the Public Reference Room by calling the SEC at (800) SEC-0330. The SEC maintains a website that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC, including Tocagen. The address of the SEC website is www.sec.gov.
We maintain a website at www.tocagen.com. Information contained in or accessible through our website does not constitute a part of this prospectus.
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC allows us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The SEC file number for the documents incorporated by reference in this prospectus is 001-38052. The documents incorporated by reference into this prospectus contain important information that you should read about us.
The following documents are incorporated by reference into this document:
 
 	•	 	our Annual Report on Form 10-K for the fiscal year ended December 31, 2017, filed with the SEC on March 9, 2018;	
 
 	•	 	our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2018, filed with the SEC on May 11, 2018;	
 
 	•	 	the information specifically incorporated by reference into our Annual Report on Form 10-K for the fiscal year ended December  31, 2017 from our definitive proxy statement on Schedule 14A (other than information furnished, rather than filed) filed with the SEC on April 30, 2018;	
 
 	•	 	our Current Reports on Form 8-K (other than information furnished, rather than filed) filed with the SEC on January  12, 2018, February 13, 2018, April 19, 2018 and May 23, 2018; and	
 
 	•	 	the description of our common stock, which is registered under Section 12 of the Exchange Act, in our registration statement on Form 8-A, filed with the SEC on April 4, 2017, including all amendments or reports filed for the purpose of updating such description.	
We also incorporate by reference into this prospectus all documents (other than Current Reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus but prior to the termination of the offering. These documents include periodic reports, such as Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as proxy statements.
We will provide to each person, including any beneficial owner, to whom a prospectus is delivered, without charge upon written or oral request, a copy of any or all of the documents that are incorporated by reference into this prospectus but not delivered with the prospectus, including exhibits which are specifically incorporated by reference into such documents. You should direct any requests for documents by writing us at 3030 Bunker Hill Street, Suite 230, San Diego, California 92109, Attn: Corporate Secretary or telephoning us at (858) 412-8400.
Any statement contained herein or in a document incorporated or deemed to be incorporated by reference into this document will be deemed to be modified or superseded for purposes of the document to the extent that a statement contained in this document or any other subsequently filed document that is deemed to be incorporated by reference into this document modifies or supersedes the statement.
 
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DISCLOSURE OF COMMISSION’S POSITION ON INDEMNIFICATION FOR
SECURITIES ACT LIABILITY
Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers or persons controlling the Company pursuant to the DGCL, we have been informed that in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.
 
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1,403,509 Shares
Forte Biosciences, Inc.
Common Stock

Prospectus Supplement

Joint Book-Running Managers

			
Ladenburg Thalmann	 	Truist Securities                      	 	Chardan	

Co-Manager
Brookline Capital Markets
a division of Arcadia Securities, LLC

October 29, 2020