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TABLE OF CONTENTS

Table of Contents

As filed with the Securities and Exchange Commission on August 7, 2020

Registration No. 333-              

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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FORM S-3

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

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GILEAD SCIENCES, INC.
(Exact Name of Registrant as Specified in Its Charter)

333 Lakeside Drive
Foster City, California 94404
(650) 574-3000
(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

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Brett A. Pletcher
Executive Vice President, Corporate Affairs,
General Counsel and Corporate Secretary
333 Lakeside Drive
Foster City, California 94404
(650) 574-3000
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

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Copy to:

Richard D. Truesdell, Jr.
Roshni Banker Cariello
Davis Polk & Wardwell
450 Lexington Avenue
New York, New York 10017
(212) 450-4000

Approximate date of commencement of proposed sale to the public:
From time to time after the effective date of this registration statement.

           If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

           If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

           If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

           If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

           If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ý

           If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

           Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

           If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act. o

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CALCULATION OF REGISTRATION FEE

(1)

Omitted pursuant to Form S-3 General Instruction II.E.

(2)

Securities registered hereunder may be sold separately, together or as units with other securities registered hereunder. An indeterminate aggregate offering price and number or amount of debt securities, common stock, preferred stock, depositary shares, warrants, subscription rights, stock purchase contracts and stock purchase units of the registrant is being registered as may from time to time be issued at currently indeterminable prices and as may be issuable upon conversion, redemption, repurchase, exchange, exercise or settlement of any securities registered hereunder, including under any applicable anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable on conversion, exchange, exercise or settlement of other securities.

(3)

In accordance with Rule 456(b) and Rule 457(r), the registrant is deferring payment of all of the registration fee.

   

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PROSPECTUS

Gilead Sciences, Inc.
Debt Securities
Common Stock
Preferred Stock
Depositary Shares
Warrants
Subscription Rights
Stock Purchase Contracts
Stock Purchase Units

        Gilead Sciences, Inc., from time to time, may offer, issue and sell (i) senior debt securities which may be convertible or non-convertible, (ii) common stock, (iii) preferred stock, (iv) depositary receipts, representing fractional shares of our preferred stock, which are called depositary shares, (v) warrants to purchase debt securities, preferred stock or common stock, (vi) subscription rights to purchase debt securities, preferred stock or common stock, (vii) stock purchase contracts obligating holders to purchase from or sell to us common stock or preferred stock at a future date or dates and (viii) stock purchase units, each consisting of a stock purchase contract and any combination of debt securities or debt obligations of third parties, including U.S. Treasury securities, which would secure the holder's obligation to purchase from or to sell to us, as the case may be, preferred stock or common stock under the stock purchase contract.

        Our common stock is listed on the NASDAQ Global Select Market under the symbol "GILD." If we decide to seek a listing of any securities offered by this prospectus, the applicable prospectus supplement will disclose the exchange or market on which such securities will be listed, if any, or where we have made an application for listing, if any.

        We may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.

        This prospectus describes some of the general terms that may apply to the offered securities. The specific terms of any securities to be offered will be described in supplements to this prospectus, which may also add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you make your investment decision.

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        Investing in our securities involves a high degree of risk. You should carefully consider the risk factors incorporated herein by reference and described under the heading "Risk Factors" beginning on page 3.

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        This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

        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 August 7, 2020.

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ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the "SEC") using a "shelf" registration process. Under this shelf process, we may, from time to time, sell any combination of the securities described in this prospectus in one or more offerings.

        This prospectus provides you with a general description of the securities that we may offer. Each time we sell securities, we will provide a prospectus supplement that contains specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered. The prospectus supplement may also add information to this prospectus or update or change information in this prospectus. If there is any inconsistency between the information in this prospectus and any prospectus supplement, you should rely on the information in the prospectus supplement. You should read carefully this prospectus and any prospectus supplement together with the additional information described under the heading "Where You Can Find More Information." We have not authorized anyone to provide you with different or additional information. We are not making an offer to sell these securities in any jurisdiction where the offer or sale of these securities is not permitted. You should assume that the information in this prospectus or any prospectus supplement, as well as the information incorporated by reference herein or therein, is accurate only as of the date of the documents containing the information. Our business, financial condition, results of operations and prospects may have changed since those dates.

        In this prospectus, except as otherwise indicated, "Gilead," the "Company," "we," "our," and "us" and similar terms refer to Gilead Sciences, Inc. and its consolidated subsidiaries.

WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains an internet site at http://www.sec.gov that contains reports, proxy and information statements and other information we have filed electronically with the SEC. These reports, proxy statements and other information can also be read on our internet site at http://gilead.com. Information on our website is not incorporated into this prospectus and is not a part of this prospectus.

        The SEC allows us to "incorporate by reference" information into this prospectus and any accompanying prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus and any accompanying prospectus supplement, except for any information superseded by information contained directly in this prospectus, any accompanying prospectus supplement or any subsequently filed document deemed incorporated by reference. This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that we have previously filed with the SEC:

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Annual Report on Form 10-K for the fiscal year ended December 31, 2019 (filed with the SEC on February 25, 2020);



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Definitive Proxy Statement on Schedule 14A (filed with the SEC on March 24, 2020);



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Quarterly Reports on Form 10-Q (filed with the SEC on May 6, 2020 and August 6, 2020);



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Current Reports on Form 8-K (filed with the SEC on January 31, 2020, March 2, 2020, May 8, 2020 and June 16, 2020); and



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the description of our common stock which is contained in the Registration Statement on Form 8-A filed December 16, 1991, under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), including any amendment or report filed for the purpose of updating such description, including Exhibit 4.9 to the Annual Report on Form 10-K for the fiscal year ended December 31, 2019 (filed with the SEC on February 25, 2020).

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        All documents filed by us pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and any accompanying prospectus supplement and before the termination of the offering shall also be deemed to be incorporated herein by reference. The most recent information that we file with the SEC automatically updates and supersedes older information. The information contained in any such filing will be deemed to be a part of this prospectus, commencing on the date on which the document is filed.

        We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed above or filed in the future, that are not deemed "filed" with the SEC, including our compensation committee report, performance graph and the certifications of our chief executive officer and chief financial officer required by Rule 13a-14(b) or Rule 15d-14(b) under the Exchange Act and Section 1350 of Chapter 63 of Title 18 of the United States Code (included in or accompanying our latest Annual Report on Form 10-K incorporated by reference herein) or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or certain exhibits furnished pursuant to Item 9.01 of Form 8-K.

        We will provide without charge upon written or oral request to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any or all of the documents which are incorporated by reference into the prospectus but not delivered with the prospectus (other than exhibits to those documents unless such exhibits are specifically incorporated by reference as an exhibit in this prospectus). Requests should be directed to Gilead Sciences, Inc., Attention: Investor Relations, 333 Lakeside Drive, Foster City, California 94404, Telephone: (650) 574-3000.

FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference contain forward-looking statements regarding future events and our future results that are subject to the safe harbors created under the Securities Act of 1933, as amended (the "Securities Act"), and the Exchange Act. Words such as "expect," "anticipate," "target," "goal," "project," "hope," "intend," "plan," "believe," "seek," "estimate," "continue," "may," "could," "should," "might," and variations of such words and similar expressions are intended to identify such forward-looking statements. In addition, any statements other than statements of historical fact are forward-looking statements, including statements regarding overall trends, operating cost and revenue trends, liquidity and capital needs, collaboration and licensing arrangements, statements regarding the anticipated future impact on our business of the ongoing coronavirus disease 2019 ("COVID-19") and related public health measures, statements regarding the development, manufacturing and distribution of remdesivir as a treatment for COVID-19 in certain markets and other statements of expectations, beliefs, future plans and strategies, anticipated events or trends and similar expressions. We have based these forward-looking statements on our current expectations about future events. These statements are not guarantees of future performance and involve risks, uncertainties and assumptions that are difficult to predict. Our actual results may differ materially from those suggested by these forward-looking statements for various reasons, including those identified below under "Risk Factors" on page 3 of this prospectus and in our Annual Report on Form 10-K for the year ended December 31, 2019 and our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2020 and June 30, 2020 (as such risk factors may be updated from time to time in our public filings). Given these risks and uncertainties, you are cautioned not to place undue reliance on forward-looking statements. The forward-looking statements included in this prospectus are made only as of the date hereof unless otherwise specified. Except as required under federal securities laws and the rules and regulations of the SEC, we do not undertake, and specifically decline, any obligation to update any of these statements or to publicly announce the results of any revisions to any forward-looking statements after the distribution of this report, whether as a result of new information, future events, changes in assumptions or otherwise.

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GILEAD SCIENCES, INC.

        We were incorporated in Delaware on June 22, 1987 and are a research-based biopharmaceutical company that discovers, develops and commercializes innovative medicines in areas of unmet medical need. With each new discovery and investigational drug candidate, we strive to transform and simplify care for people with life-threatening illnesses around the world. We have operations in more than 35 countries worldwide, with headquarters in Foster City, California. Our primary areas of focus include viral diseases, inflammatory and fibrotic diseases and oncology. We seek to add to our existing portfolio of products and product candidates through our internal discovery and clinical development programs, acquisitions, in-licensing, options and other strategic collaborations.

        Our portfolio of marketed products includes AmBisome®, Atripla®, Biktarvy®, Cayston®, Complera®/Eviplera®, Descovy®, Descovy for PrEP®, Emtriva®, Epclusa®, Genvoya®, Harvoni®, Hepsera®, Letairis®, Odefsey®, Ranexa®, Sovaldi®, Stribild®, Tecartus™, Truvada®, Truvada for PrEP®, Tybost®, Veklury® (remdesivir), Vemlidy®, Viread®, Vosevi®, Yescarta® and Zydelig®. The approval status of Veklury (remdesivir) varies worldwide, and Veklury (remdesivir) is not approved in the United States and is authorized for use under an Emergency Use Authorization. We also sell and distribute authorized generic versions of Epclusa and Harvoni in the United States through our separate subsidiary, Asegua Therapeutics, LLC. In addition, we sell and distribute certain products through our corporate partners under collaborative agreements.

        Our principal executive offices are located at 333 Lakeside Drive, Foster City, California 94404. The telephone number of our principal executive offices is (650) 574-3000.

RISK FACTORS

        Investing in our securities involves a high degree of risk. Before acquiring any offered securities pursuant to this prospectus, you should carefully consider the information contained or incorporated by reference in this prospectus or in any accompanying prospectus supplement, including, without limitation, the risk factors described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2019 and our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2020 and June 30, 2020, which are incorporated herein by reference (as such risk factors may be updated in our other filings with the SEC pursuant to Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act), and the risk factors described in any applicable prospectus supplement before making an investment decision. The occurrence of any of these risks might cause you to lose all or a part of your investment in the offered securities. See "Where You Can Find More Information" included elsewhere in this prospectus.

USE OF PROCEEDS

        Except as may be otherwise set forth in the applicable prospectus supplement accompanying this prospectus, the net proceeds from the sale of the securities offered by this prospectus will be used for general corporate purposes.

DESCRIPTION OF SECURITIES

        This prospectus contains summary descriptions of the debt securities, common stock, preferred stock, depositary shares, warrants, subscription rights, stock purchase contracts and stock purchase units that we may sell from time to time. These summary descriptions are not meant to be complete descriptions of each security. The particular terms of any security will be described in the related prospectus supplement.

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DESCRIPTION OF DEBT SECURITIES

        We may issue senior debt securities under an indenture, dated March 30, 2011, between us and Wells Fargo Bank, National Association, as trustee, which we refer to as the "base indenture." As used in this prospectus, "debt securities" means our direct unsecured general obligations and may include debentures, notes, bonds or other evidences of indebtedness that we issue and the trustee authenticates and delivers under the base indenture. The prospectus supplement relating to any offering of debt securities will describe more specific terms of the debt securities being offered.

        Debt securities will be issued under the base indenture in one or more series established pursuant to a supplemental indenture or a resolution duly adopted by our board of directors or a duly authorized committee thereof. The base indenture does not limit the aggregate principal amount of debt securities that may be issued thereunder, or the amount of series that may be issued. In this prospectus, we refer to the base indenture (together with each applicable supplemental indenture or resolution establishing the applicable series of debt securities) as the "indenture." The indenture will be subject to, and governed by, the Trust Indenture Act of 1939.

        The summary set forth below does not purport to be complete and is subject to and qualified in its entirety by reference to the base indenture and the supplemental indenture or board resolution (including the form of debt security) relating to the applicable series of debt securities, the form of each of which is or will be filed or incorporated by reference as an exhibit to the registration statement of which this prospectus is a part and incorporated herein by reference.

General

        The debt securities will be our unsecured obligations and will rank equally with all of our other unsecured and unsubordinated debt from time to time outstanding. Our secured debt will be effectively senior to the debt securities to the extent of the value of the assets securing such debt. Unless otherwise indicated in a prospectus supplement, the debt securities will be exclusively our obligations and not those of our subsidiaries and therefore the debt securities will be structurally subordinate to the debt and liabilities of any of our subsidiaries.

        The applicable prospectus supplement will describe the specific terms of each series of debt securities being offered, including some or all of the following:

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the title of the debt securities;



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the price at which the debt securities will be issued (including any issue discount);



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any limit on the aggregate principal amount of the debt securities;



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the date or dates (or manner of determining the same) on which the debt securities will mature;



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the rate or rates (which may be fixed or variable) per annum (or the method or methods by which such rate or rates will be determined) at which the debt securities will bear interest, if any, and the date or dates from which such interest will accrue;



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the date or dates on which such interest will be payable and the record dates for such interest payment dates and the basis upon which interest shall be calculated if other than that of a 360-day year of twelve 30-day months;



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if the trustee in respect of the debt securities is other than Wells Fargo Bank, National Association (or any successor thereto), the identity of the trustee;



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any mandatory or optional sinking fund or purchase fund or analogous provision;



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whether the debt securities are to be issued in individual certificates to each holder or in the form of global securities held by a depositary;

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any provisions relating to the date after which, the circumstances under which, and the price or prices at which the debt securities may, pursuant to any optional or mandatory redemption provisions, be redeemed at our option or of the holder thereof and certain other terms and provisions of such optional or mandatory redemption;



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if the debt securities are denominated in other than United States dollars, the currency or currencies (including composite currencies) in which the debt securities are denominated;



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if payments of principal (and premium, if any) or interest, if any, in respect of the debt securities are to be made in a currency other than United States dollars or the amounts of such payments are to be determined with reference to an index based on a currency or currencies other than that in which the debt securities are denominated, the currency or currencies (including composite currencies) or the manner in which such amounts are to be determined, respectively;



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if other than, or in addition to, the events of default described in the base indenture, the events of default with respect to the debt securities of that series;



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any provisions relating to the conversion of debt securities into debt securities of another series or shares of our capital stock or any other equity securities or property;



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any provisions restricting defeasance of the debt securities;



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any covenants or other restrictions on our operations;



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conditions to any merger or consolidation; and



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any other terms of the debt securities. (Section 3.1)

        Unless otherwise indicated in a prospectus supplement in respect of which this prospectus is being delivered, principal of, premium, if any, and interest, if any, on the debt securities (other than debt securities issued as global securities) will be payable, and the debt securities (other than debt securities issued as global securities) will be exchangeable and transfers thereof will be registrable, at the office of the trustee with respect to such series of debt securities and at any other office maintained at that time by us for such purpose, provided that, at our option, payment of interest may be made by check mailed to the address of the holder as it appears in the register of the debt securities. (Section 3.4)

        Unless otherwise indicated in a prospectus supplement relating thereto, the debt securities will be issued only in fully registered form, without coupons, in denominations of $2,000 and integral multiples of $1,000 in excess thereof. (Section 3.2) For certain information about debt securities issued in global form, see "—Global Securities" below. No service charge shall be made for any registration of transfer or exchange of the securities, but we may require payment of a sum sufficient to cover any transfer tax or other governmental charge payable in connection therewith. (Section 3.6)

        Debt securities bearing no interest or interest at a rate that at the time of issuance is below the prevailing market rate will be sold at a discount below their stated principal amount. Special U.S. federal income tax considerations applicable to any such discounted debt securities or to certain debt securities issued at par which are treated as having been issued at a discount for U.S. federal income tax purposes will be described in the prospectus supplement in respect of which this prospectus is being delivered, if applicable.

        Debt securities may be issued, from time to time, with the principal amount payable on the applicable principal payment date, or the amount of interest payable on the applicable interest payment date, to be determined by reference to one or more currency exchange rates, commodity prices, equity indices or other factors. In such cases, holders of such debt securities may receive a principal amount on any principal payment date, or a payment of interest on any interest payment date, that is greater than or less than the amount of principal or interest payable on such dates, depending upon the value

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on such dates of the applicable currency, commodity, equity index or other factor. Information, if any, as to the methods for determining the amount of principal or interest payable on any date, the currencies, commodities, equity indices or the factors to which the amount payable on such date is linked and certain additional tax considerations applicable to the debt securities will be set forth in a prospectus supplement in respect of which this prospectus is being delivered.

        The indenture provides that the trustee and the paying agent shall promptly pay to us, upon request, any money held by them for the payment of principal (and premium, if any) or interest that remains unclaimed for two years. In the event the trustee or the paying agent returns money to us following such two-year period, the holders of the debt securities thereafter shall be entitled to payment only from us, subject to all applicable escheat, abandoned property and similar laws. (Section 11.7)

        The base indenture does not limit the amount of additional unsecured indebtedness that we or any of our subsidiaries may incur. Unless otherwise specified in the resolutions or in any supplemental indenture establishing the terms of the debt securities, the terms of the debt securities do not afford holders of the debt securities protection in the event of a highly leveraged or other similar transaction involving us that may adversely affect the holders of the debt securities. Debt securities of any particular series need not be issued at the same time and, unless otherwise provided, a series may be re-opened, without the consent of the holders of such debt securities, for issuances of additional debt securities of that series, unless otherwise specified in the resolutions or any supplemental indenture establishing the terms of the debt securities. (Section 3.1)

Certain Covenants

        The following restrictive covenants will apply to each series of debt securities issued under the indenture, unless otherwise specified in any supplemental indenture or resolution establishing the terms of the debt securities of any series. See "—Certain Definitions" below for the definitions of certain of the defined terms used herein.

Limitations on Liens

        Other than as provided under "—Exempted Liens and Sale and Leaseback Transactions," we will not, nor will we permit any Restricted Subsidiary to, create, incur, issue, assume or guarantee any Debt if such Debt is secured by a Lien upon any Restricted Property or on the capital stock or Debt of any Restricted Subsidiary, without, in any such case, effectively providing that the debt securities will be secured equally and ratably by such Lien with such secured Debt; provided, however, that this restriction will not apply to:

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Liens existing on the date of the indenture or Liens existing on property, capital stock or Debt of any Person at the time it becomes a Restricted Subsidiary;



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Any Lien existing on property when acquired, constructed or improved and which Lien (i) secured or provided for the payment of all or any part of the acquisition costs of the property or the cost of construction or improvement thereof and (ii) is created prior to, at the same time or within one year after, the completion of such acquisition, construction or improvement to the property, as the case may be;



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Liens on property of a Person existing at the time such Person is merged into or consolidated with us or a Restricted Subsidiary or at the time of a sale, lease or other disposition of the properties of a Person as an entirety or substantially as an entirety to us or a Restricted Subsidiary; provided, that such Lien was not incurred in anticipation of such transaction and was in existence prior to such transaction;

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Any Lien arising by reason of deposits with, or the giving of any form of security to, any governmental agency or any body created or approved by law or governmental regulation;



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Liens securing Debt of a Restricted Subsidiary owed to us or another Restricted Subsidiary;



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Liens for taxes, fees, assessments or other governmental charges which are not delinquent or remain payable without penalty;



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Carriers', warehousemen's, materialmen's, repairmen's, mechanics', landlords' and other similar Liens arising in the ordinary course of business which are not delinquent or remain payable without penalty or which are being contested in good faith and by appropriate proceedings, which proceedings have the effect of preventing the forfeiture or sale of the property or assets subject to any such Lien if reserves or other appropriate provisions, if any, as shall be required by generally accepted accounting principles have been made therefor;



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Liens (other than any Lien imposed by ERISA) consisting of pledges or deposits required in the ordinary course of business in connection with workers' compensation, unemployment insurance and other social security legislation;



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Liens on property securing (i) the non-delinquent performance of bids, trade contracts (other than for borrowed money), leases, statutory obligations, (ii) contingent obligations on surety and appeal bonds and (iii) other non-delinquent obligations of a like nature; in each case, incurred in the ordinary course of business, provided that all such Liens under this bullet point in the aggregate would not (even if enforced) cause a material adverse change in, or a material adverse effect upon, the operations, business, properties, liabilities (actual or contingent), condition (financial or otherwise) or prospects of the Company and its Subsidiaries taken as a whole;



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Liens securing obligations in respect of capital leases on assets subject to such leases; provided that such leases are otherwise permitted pursuant to the second or third bullets under the covenant "—Limitations on Sale and Leaseback Transactions" set forth below;



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Liens securing reimbursement obligations with respect to letters of credit arising by operation of law under Section 5-118(a) of the Uniform Commercial Code;



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Liens arising solely by virtue of any banker's liens, rights of set-off or similar rights and remedies as to deposit accounts or other funds maintained with a creditor depository institution; provided that (i) such deposit account is not a dedicated cash collateral account and is not subject to restrictions against access by us in excess of those set forth by regulations promulgated by the Board of Governors of the Federal Reserve System of the United States, and (ii) such deposit account is not intended by us or any Subsidiary to provide collateral to the depository institution;



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Easements, right-of-way restrictions and other similar encumbrances incurred in the ordinary course of our business which, in the aggregate, are not substantial in amount, and which do not in any case materially detract from the value of the property subject thereto or interfere with the ordinary course of our and our Subsidiaries' business; and



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Any extension, renewal or replacement (or successive extensions, renewals or replacements), in whole or in part, of any permitted Lien referred to in the bullets set forth above, inclusive of any Lien existing at the date of the indenture; provided that the obligation secured by such new Lien shall not extend beyond the property subject to the existing Lien and is not greater in amount than the obligations secured by the Lien extended, renewed or replaced (plus an amount in respect of reasonable financing fees and related transaction costs). (Section 5.2)

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Limitations on Sale and Leaseback Transactions

        Other than as provided under "—Exempted Liens and Sale and Leaseback Transactions," we will not, and will not permit any Restricted Subsidiary to, enter into any sale and leaseback transaction with respect to any Restricted Property, except a lease for a period (including extensions or renewals at our option or the option of a Restricted Subsidiary) of three years or less. Notwithstanding the foregoing, we or any Restricted Subsidiary may enter into a sale and leaseback transaction if:

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The lease is between us and a Restricted Subsidiary or between Restricted Subsidiaries;



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We or such Restricted Subsidiary would, at the time of entering into such sale and leaseback transaction, be entitled pursuant to the covenant described under "—Limitations on Liens" above, to incur Debt secured by a Lien on such Restricted Property involved in a principal amount at least equal to the Attributable Debt of such transaction without equally and ratably securing the debt securities; or



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We or any of our Restricted Subsidiaries, during the six months following the effective date of the sale and leaseback transaction, apply an amount equal to the greater of the net proceeds of such sale or transfer or the fair value of the Restricted Property that we or our Restricted Subsidiary lease in the transaction to the voluntary retirement of the debt securities or other Debt of ours or that of any Restricted Subsidiary, provided that such Debt (i) ranks pari passu or senior to the debt securities under the indenture and (ii) has a stated maturity which is either more than 12 months from the date of such application or which is extendable or renewable at the option of the obligor thereon to a date more than 12 months from the date of such application. (Section 5.3)

Exempted Liens and Sale and Leaseback Transactions

        Notwithstanding the restrictions described under the headings "—Limitations on Liens" or "—Limitations on Sale and Leaseback Transactions," we or any Restricted Subsidiary of ours may create or assume any Liens or enter into any Sale and Leaseback Transactions not otherwise permitted as described under such headings, if the sum of the following does not exceed 15% of Consolidated Net Tangible Assets:

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the outstanding Indebtedness secured by such Liens (not including any Liens permitted under "—Limitations on Liens" which amount does not include any Liens permitted under the provisions of this "—Exempted Liens and Sale and Leaseback Transactions"); plus



•

all Attributable Debt in respect of such Sale and Leaseback Transactions entered into (not including and Sale and Leaseback Transactions permitted under "—Limitations on Sale and Leaseback Transactions" which amount does not include any Sale and Leaseback Transactions permitted under the provisions of this "—Exempted Liens and Sale and Leaseback Transactions"),

measured, in each case, at the time such Lien is incurred or any such Sale and Leaseback Transaction is entered into by us or such Restricted Subsidiary of ours. (Section 5.4)

Certain Definitions

        Set forth below are certain of the defined terms used in the indenture.

        "Attributable Debt" means, in respect of a sale and leaseback transaction, as of any particular time, the present value (discounted at the rate of interest implicit in the terms of the lease involved in such sale and leaseback transaction, as determined in good faith by us) of the obligation of the lessee thereunder for rental payments (excluding, however, any amounts required to be paid by such lessee, whether or not designated as rent or additional rent, on account of maintenance and repairs, insurance,

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taxes, assessments, water rates or similar charges or any amounts required to be paid by such lessee thereunder contingent upon the amount of sales, maintenance and repairs, insurance, taxes, assessments, water rates or similar charges) during the remaining term of such lease (including any period for which such lease has been extended or may, at the option of the lessor, be extended).

        "Consolidated Net Tangible Assets" means the total amount of assets (less applicable reserves and other properly deductible items) after deducting (1) all current liabilities (excluding the amount of those which are by their terms extendable or renewable at the option of the obligor to a date more than 12 months after the date as of which the amount is being determined) and (2) all customer lists, computer software, licenses, patents, patent applications, copyrights, trademarks, trade names, goodwill, capitalized research and development costs and other like intangibles, treasury stock and unamortized debt discount and expense, and all other like intangible assets, all as stated on the Company's most recent publicly available consolidated balance sheet preceding the date of determination and determined in accordance with generally accepted accounting principles.

        "Debt" means any and all of the obligations of a Person for money borrowed which in accordance with generally accepted accounting principles would be reflected on the balance sheet of such Person as a liability as of the date of which the Debt is to be determined.

        "Lien" means any mortgage, pledge, hypothecation, assignment, deposit arrangement, encumbrance, lien (statutory or other), charge, or preference, priority or other security interest or preferential arrangement of any kind or nature whatsoever (including any conditional sale or other title retention agreement, and any financing lease having substantially the same economic effect as any of the foregoing) on or with respect to any property.

        "Person" means an individual, a corporation, a company, a voluntary association, a partnership, a trust, a joint venture, a limited liability company, an unincorporated organization, or a government or any agency, instrumentality or political subdivision thereof.

        "Restricted Property" means, as to any particular series of notes, any manufacturing facility or plant owned, or leased, by the Company or a Restricted Subsidiary and located within the United States, including Puerto Rico, the gross book value (including related land, machinery and equipment without deduction of any depreciation reserves) of which is not less than 1% of Consolidated Tangible Net Assets as stated on the Company's most recent publicly available consolidated balance sheet preceding the date of determination other than any such manufacturing facility or plant which the board of directors reasonably determines is not material to the operation of the Company's business and its Subsidiaries, taken as a whole.

        "Restricted Subsidiary" means a Subsidiary (i) which is a "significant subsidiary" as defined in Rule 1-02(w) of Regulation S-X under the U.S. federal securities laws or (ii) which owns a Restricted Property; provided, however, that the term shall not include any Subsidiary which is solely or primarily engaged in the business of providing or obtaining financing for the sale or lease of products sold or leased by us or any Subsidiary.

        "Subsidiary" means, with respect to any Person, any corporation, partnership, joint venture, limited liability company or other business entity of which a majority of the outstanding shares or other interests having voting power is at the time directly or indirectly owned or controlled by such Person or one or more of the Subsidiaries of such Person. Unless the context otherwise requires, all references to Subsidiary or Subsidiaries herein shall refer to our Subsidiaries.

        "United States" means the United States of America (including the states thereof and the District of Columbia), its territories and possessions and other areas subject to its jurisdiction.

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Merger, Consolidation and Sale

        The indenture generally provides that we may not consolidate with or merge into, or sell, transfer or convey, including by lease, all or substantially all of our assets to another entity, unless: (i) the resulting, surviving or transferee entity (A) is a corporation or entity organized under the laws of the United States and (B) if other than us, it assumes by a supplemental indenture all our obligations under the debt securities and the indenture, (ii) immediately after giving effect to such transaction no Event of Default (as defined herein) and no circumstances which, after notice or lapse of time or both, would become an Event of Default, shall have happened and be continuing, and (iii) we shall have delivered to the trustee an officers' certificate and an opinion of counsel, each stating that such consolidation, merger or transfer and such supplemental indenture comply with the indenture. (Section 6.1)

Global Securities

        The debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with the depositary identified in the applicable prospectus supplement. Unless it is exchanged in whole or in part for debt securities in definitive form, a global security may not be transferred. However, transfers of the whole security between the depositary for that global security and its nominees or their respective successors are permitted.

        Unless otherwise provided in the applicable prospectus supplement, The Depository Trust Company, New York, New York, which we refer to in this prospectus as "DTC," will act as depositary for each series of global securities. Beneficial interests in global securities will be shown on, and transfers of global securities will be effected only through, records maintained by DTC and its participants.

Amendment, Supplement and Waiver

        Subject to certain exceptions, the indenture or the debt securities of any series may be amended or supplemented with the written consent of the holders of not less than a majority in principal amount of the then outstanding debt securities of the affected series; provided that we and the trustee may not, without the consent of the holder of each outstanding debt security of such series affected thereby:

•

reduce the amount of debt securities of such series whose holders must consent to an amendment, supplement or waiver;



•

reduce the rate of or extend the time for payment of interest on any debt security of such series;



•

reduce the principal of or extend the fixed maturity of any debt security of such series;



•

reduce the portion of the principal amount of a discounted security of such series payable upon acceleration of its maturity;



•

impair the right to sue for the enforcement of payment at the maturity of the debt security; or



•

make any debt security of such series payable in money other than that stated in such debt security. (Section 12.2)

        Any past default or failure to comply with any provisions may be waived with the consent of the holders of a majority in principal amount of the debt securities of the affected series, except a default in payment of principal or interest or in respect of other provisions requiring the consent of the holder of each such debt security of that series in order to amend. Without the consent of any holder of debt securities of such series, we and the trustee may amend or supplement the indenture or the debt securities without notice to, among others:

•

cure any ambiguity, omission, defect or inconsistency;

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•

to provide for uncertificated debt securities in addition to or in place of certificated debt securities;



•

to comply with the provisions of the indenture concerning mergers, consolidations and transfers of all or substantially all of our assets;



•

to appoint a trustee other than Wells Fargo Bank, National Association (or any successor thereto) as trustee in respect of one or more series of debt securities;



•

to add, change or eliminate provisions of the indenture as shall be necessary or desirable in accordance with any amendment to the Trust Indenture Act of 1939; or



•

to make any change that does not materially adversely affect the rights of any holder of that series of debt securities. (Section 12.1)

        Whenever we request the trustee to take any action under the indenture, including a request to amend or supplement the applicable indenture without the consent of any holder of debt securities, we are required to furnish the trustee with an officers' certificate and an opinion of counsel to the effect that all conditions precedent to the action have been complied with. Without the consent of any holder of debt securities, the trustee may waive compliance with any provisions of the indenture or the debt securities if the waiver does not materially adversely affect the rights of any such holder.

Default and Remedies

        An "Event of Default" under the indenture in respect of any series of debt securities is:

•

default for 30 days in payment of interest on the debt securities of that series;



•

default in payment of principal, or any premium on the debt securities of that series;



•

default for 30 days in the payment of any sinking fund installment on the debt securities of that series;



•

failure by us for 90 days after notice to us to comply with any of our other agreements in the applicable indenture for the benefit of holders of debt securities of that series;



•

certain events of bankruptcy, insolvency or reorganization; and



•

any other event of default specifically provided for by the terms of such series, as described in the related prospectus supplement. (Section 7.1)

        If an Event of Default (other than an Event of Default relating to certain events of bankruptcy, insolvency or reorganization) occurs and is continuing, the trustee or the holders of at least 25% in principal amount of the outstanding debt securities of the affected series may declare the debt securities of that series to be due and payable immediately, but under certain conditions such acceleration may be rescinded by the holders of a majority in principal amount of the outstanding debt securities of the affected series. In case of certain events of bankruptcy, insolvency or reorganization involving us, the principal and accrued and unpaid interest on the outstanding debt securities of the affected series will automatically become immediately due and payable. In addition, an Event of Default applicable to a particular series of debt securities that causes the one or more series to be accelerated may give rise to a cross-default under our existing and future borrowing arrangements. (Section 7.2)

        No holder of debt securities may pursue any remedy against us under the indenture (other than with respect to the right to receive payment of principal (and premium, if any) or interest, if any) unless such holder previously shall have given to the trustee written notice of default and unless the holders of at least 25% in principal amount of the debt securities of the affected series shall have requested the trustee to pursue the remedy and shall have offered the trustee indemnity or security

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satisfactory to it, the trustee shall not have complied with the request within 60 days of receipt of the request and the offer of indemnity or security, and the trustee shall not have received direction inconsistent with the request during such 60-day period from the holders of a majority in principal amount of the debt securities of the affected series. (Section 7.5)

        Holders of debt securities may not enforce the indenture or the debt securities except as provided in the indenture. The trustee may refuse to enforce the indenture or the debt securities unless it receives indemnity or security satisfactory to it from us or, under certain circumstances, the holders of debt securities seeking to direct the trustee to take certain actions under the indenture against any loss, liability or expense. Subject to certain limitations, holders of a majority in principal amount of the debt securities of any series may direct the trustee in writing in its exercise of any trust or power under the indenture in respect of that series. The indenture provides that the trustee will give to the holders of debt securities of any particular series notice of all defaults actually known to it, within 90 days after the occurrence of any default with respect to such debt securities, unless the default shall have been cured or waived. The trustee may withhold from holders of debt securities notice of any continuing default (except a default in payment of principal or interest) if it determines in good faith that withholding such notice is in the interests of such holders. We are required annually to certify to the trustee in writing as to the compliance by us with all conditions and any covenants under the indenture and the absence of a default thereunder, or as to any such default that existed. (Section 10.3)

        Our directors, officers, employees and stockholders, as such, shall not have any liability for any of our obligations under the debt securities or the indenture or for any claim based on, in respect of, or by reason of such obligations or their creation. By accepting a debt security, each holder of such debt security waives and releases all such claims and liability. This waiver and release are part of the consideration for the issue of the debt securities. (Section 15.1)

Satisfaction, Discharge and Defeasance

        The indenture provides, unless such provision is made inapplicable to the debt securities of any series issued pursuant to the indenture, that we may, subject to certain conditions described below, discharge certain obligations to holders of debt securities that have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the trustee, in trust, funds in an amount sufficient to pay the entire indebtedness on such debt securities in respect of principal (and premium, if any) and interest to the date of such deposit (if such debt securities have become due and payable) or to the stated maturity and redemption date, as the case may be.

        The indenture provides that we may elect either:

•

to defease and be discharged from all of our obligations with respect to the debt securities of a series (this is known as "defeasance"); or



•

to be released from our obligations with respect to the debt securities of a series under the restrictions described under "—Certain Covenants" or, if provided pursuant to the indenture, our obligations under any other covenant, and any omission to comply with such obligations will not constitute an event of default with respect to those debt securities (this is known as "covenant defeasance");

in either case upon the irrevocable deposit by us with the trustee, in trust, of an amount, in the currency in which those debt securities are payable at stated maturity, or government obligations, or both, applicable to those debt securities that through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient in the opinion of a nationally recognized investment bank, appraisal firm or firm of independent certified public accountants to pay

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the principal of (and premium, if any) and interest on those debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates.

        Such a trust will only be permitted to be established if, among other things, we have delivered to the trustee an opinion of counsel to the effect that the holders of such debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the defeasance or covenant defeasance had not occurred, and such opinion of counsel, in the case of defeasance, will be required to refer to and be based upon a ruling of the Internal Revenue Service or a change in applicable U.S. federal income tax law occurring after the date of the indenture. (Section 11.3)

Governing Law

        The debt securities and the indenture will be governed by and construed in accordance with the laws of the State of New York.

Trustee

        Wells Fargo Bank, National Association will act as trustee under the indenture. Wells Fargo Bank, National Association is a documentation agent and a lender to us under our senior credit facility, and also provides from time to time other services to us in the ordinary course of business.

Additional Information

        The indenture is an exhibit to the registration statement of which this prospectus is a part. Any person who receives this prospectus may obtain a copy of such indenture without charge by writing to us at the address listed under the caption "Where You Can Find More Information."

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DESCRIPTION OF CAPITAL STOCK

General

        This section summarizes the general terms of our capital stock. The following description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our restated certificate of incorporation ("certificate") and our amended and restated bylaws ("bylaws"), each of which has been publicly filed with the SEC and has been incorporated in this prospectus by reference. See "Where You Can Find More Information" for information on how to obtain copies.

Authorized Capital Stock

        Our authorized capital stock consists of 5,600,000,000 shares of common stock, $0.001 par value, and 5,000,000 shares of preferred stock, $0.001 par value per share. We have one class of securities registered under Section 12 of the Securities Exchange Act of 1934, our common stock, which is listed on the Nasdaq Global Select Market under the symbol "GILD."

Common Stock

        Voting rights.    The holders of our common stock are entitled to one vote per share on all matters submitted to a vote of stockholders. A majority of the votes cast is required for stockholders to elect directors (except that directors are elected by a plurality of the votes cast in a contested director election). All other matters put to a stockholder vote generally require the approval of a majority of the shares entitled to vote on the matter and present in person or represented by proxy, except for certain matters for which our certificate and bylaws require the approval of a majority of the voting power of the outstanding shares entitled to vote on the matter and except as otherwise required by law. Stockholders do not have cumulative voting rights.

        Dividends.    The holders of our common stock have the right to receive dividends if they are declared by our board of directors and there are sufficient funds to legally pay dividends, subject to the rights of the holders of any outstanding preferred stock to receive preferential dividends.

        Liquidation.    Upon our liquidation, holders of our common stock would share ratably in any assets available for distribution to stockholders after payment of all of our obligations and the aggregate liquidation preference (including accrued and unpaid dividends) of any outstanding preferred stock.

        Preemptive, subscription and conversion rights.    Our common stock is not redeemable and has no preemptive, subscription or conversion rights.

        Transfer agent.    The transfer agent and registrar for our common stock is Computershare Trust Company, N.A.

        The rights, preferences and privileges of holders of our common stock are subject to the rights of the holders of shares of any series of preferred stock which we may issue.

Preferred Stock

        Our board of directors has the authority, without further action by our stockholders, to issue up to 5,000,000 shares of preferred stock, none of which are outstanding. Our board of directors may issue preferred stock in one or more series and fix the rights, preferences, privileges and restrictions of such preferred stock, including:

•

dividend rights;



•

dividend rate;



•

conversion rights;

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•

voting rights;



•

rights and terms of redemption;



•

redemption price or prices;



•

the liquidation preferences of any wholly unissued series of preferred stock; and



•

the number of shares constituting any series or the designation of such series.

        The issuance of preferred stock could decrease the amount of earnings and assets available for distribution to the holders of our common stock or adversely affect the rights and powers, including voting rights, of the holders of our common stock.

Anti-Takeover Provisions

        Some provisions of our certificate, bylaws and Delaware law may have the effect of delaying, deferring or discouraging another party from acquiring control of us.

        Our certificate and bylaws provide that:

•

the board of directors is authorized to issue preferred stock without stockholder approval;



•

the board of directors is expressly authorized to make, alter or repeal any provision of our bylaws;



•

stockholders may not cumulate votes in the election of directors;



•

special meetings of the stockholders may be called by the stockholders only upon the written request of one or more stockholders of record that own, or who are acting on behalf of persons who own, shares representing 20% or more of the voting power of the then outstanding shares of capital stock entitled to vote on the matter or matters to be brought before the proposed special meeting, and otherwise in accordance with the certificate and bylaws;



•

stockholders must satisfy advance notice procedures to submit proposals or nominate directors for consideration at a stockholders' meeting;



•

a stockholder, or a group of up to 20 stockholders, owning 3% or more of our outstanding common stock continuously for at least three years may nominate and include in our proxy materials director nominees constituting up to the greater of (i) 20% of the board of directors (rounded down to the nearest whole number) or (ii) two directors, provided that the stockholder(s) and the nominee(s) satisfy the requirements specified in our bylaws and subject to the other terms and conditions set forth in our bylaws;



•

action by stockholders by written consent may be taken only upon written request that a record date be fixed for such purpose by one or more stockholders of record that own shares representing 20% or more of the then outstanding shares of common stock, and otherwise in accordance with the certificate and bylaws; and



•

we will indemnify officers and directors against losses that they may incur as a result of investigations and legal proceedings resulting from their services to us, which may include services in connection with takeover defense measures.

        In addition, we are subject to the provisions of Section 203 of the Delaware General Corporation Law ("DGCL"). In general, the statute prohibits a publicly held Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date that the person became an interested stockholder unless, with some exceptions, the business combination or the transaction in which the person became an interested stockholder is approved in a prescribed manner. Generally, a "business combination" includes a merger, asset or stock sale or other

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transaction resulting in a financial benefit to the stockholder, and an "interested stockholder" is a person who, together with affiliates and associates, owns (or within three years prior, did own) 15% or more of the corporation's outstanding voting stock. This provision may have the effect of delaying, deferring or preventing a change in control without further action by the stockholders.

Exclusive Forum

        Our certificate provides that unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for: (i) any derivative action or proceeding brought on our behalf; (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer, employee or agent of Gilead or our stockholders; (iii) any action asserting a claim against us arising pursuant to any provision of the DGCL, or our certificate or our bylaws; or (iv) any action asserting a claim against us or any of our directors, officers, employees or agents governed by the internal affairs doctrine; provided, however, that in the event the Court of Chancery of the State of Delaware lacks jurisdiction over any such action or proceeding, the sole and exclusive forum for such action or proceeding shall be another state or federal court located within the State of Delaware. Our certificate also provides that any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock will be deemed to have notice of and to have consented to this choice of forum provision. It is possible that a court of law could rule that the choice of forum provision contained in our certificate is inapplicable or unenforceable if it is challenged in a proceeding or otherwise.

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DESCRIPTION OF DEPOSITARY SHARES

        We may issue depositary shares representing fractional interests in shares of our preferred stock of any series. The following description sets forth certain general terms and provisions of the depositary shares to which any prospectus supplement may relate. The particular terms of the depositary shares to which any prospectus supplement may relate and the extent, if any, to which the general terms and provisions may apply to the depositary shares so offered will be described in the applicable prospectus supplement. To the extent that any particular terms of the depositary shares, depositary agreements and depositary receipts described in a prospectus supplement differ from any of the terms described below, then the terms described below will be deemed to have been superseded by that prospectus supplement. We encourage you to read the applicable depositary agreement and depositary receipts for additional information before you decide whether to purchase any of our depositary shares.

        In connection with the issuance of any depositary shares, we will enter into a depositary agreement with a bank or trust company, as depositary, which will be named in the applicable prospectus supplement. Depositary shares will be evidenced by depositary receipts issued pursuant to the related depositary agreement. Immediately following our issuance of the security related to the depositary shares, we will deposit the shares of our preferred stock with the relevant depositary and will cause the depositary to issue, on our behalf, the related depositary receipts. Subject to the terms of the depositary agreement, each owner of a depositary receipt will be entitled, in proportion to the fractional interest in the share of preferred stock represented by the related depositary share, to all the rights, preferences and privileges of, and will be subject to all of the limitations and restrictions on, the preferred stock represented by the depositary receipt (including, if applicable, dividend, voting, conversion, exchange, redemption, sinking fund, subscription and liquidation rights).

DESCRIPTION OF WARRANTS

        We may issue warrants to purchase debt securities, preferred stock or common stock. We may issue warrants independently or together with other securities. Warrants sold with other securities may be attached to or separate from the other securities. We will issue warrants under one or more warrant agreements between us and a bank or trust company, as warrant agent, that we will name in the prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

        The prospectus supplement relating to any warrants we offer will include specific terms relating to the offering. These terms may include some or all of the following:

•

the title of such warrants;



•

the aggregate number of such warrants;



•

the price or prices at which such warrants will be issued;



•

the currency or currencies, including composite currencies, in which the price of such warrants may be payable;



•

the designation and terms of the securities purchasable upon exercise of such warrants and the number of such securities issuable upon exercise of such warrants;



•

the price at which and the currency or currencies, including composite currencies, in which the securities purchasable upon exercise of such warrants may be purchased;



•

the date on which the right to exercise such warrants shall commence and the date on which such right will expire;



•

whether such warrants will be issued in registered form or bearer form;

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•

if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;



•

if applicable, the designation and terms of the securities with which such warrants are issued and the number of such warrants issued with each such security;



•

if applicable, the date on and after which such warrants and the related securities will be separately transferable;



•

information with respect to book-entry procedures, if any; and



•

any other terms of such warrants, including terms, procedures and limitations relating to the exchange and exercise of such warrants.

        The description in the prospectus supplement will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement, which will be filed with the SEC.

DESCRIPTION OF SUBSCRIPTION RIGHTS

        We may issue subscription rights to purchase debt securities, preferred stock or common stock. These subscription rights may be issued independently or together with any other security offered hereby and may or may not be transferable by the shareholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

        The applicable prospectus supplement will describe the specific terms of any offering of subscription rights for which this prospectus is being delivered, including the following:

•

the price, if any, for the subscription rights;



•

the exercise price payable for each share of debt securities, preferred stock or common stock upon the exercise of the subscription rights;



•

the number of subscription rights issued to each shareholder;



•

the number and terms of the shares of debt securities, preferred stock or common stock which may be purchased per each subscription right;



•

the extent to which the subscription rights are transferable;



•

any other terms of the subscription rights, including the terms, procedures and limitations relating to the exchange and exercise of the subscription rights;



•

the date on which the right to exercise the subscription rights shall commence, and the date on which the subscription rights shall expire;



•

the extent to which the subscription rights may include an over-subscription privilege with respect to unsubscribed securities; and



•

if applicable, the material terms of any standby underwriting or purchase arrangement entered into by us in connection with the offering of subscription rights.

        The description in the applicable prospectus supplement of any subscription rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate, which will be filed with the SEC if we offer subscription rights. For more information on how you can obtain copies of any subscription rights certificate if we offer subscription rights, please see the section entitled "Where You Can Find More Information."

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DESCRIPTION OF STOCK PURCHASE CONTRACTS AND STOCK PURCHASE UNITS

        We may issue stock purchase contracts, including contracts obligating holders to purchase from or sell to us, and us to sell to or purchase from the holders, a specified number of shares of common stock or shares of preferred stock at a future date or dates. The consideration per share of common stock or preferred stock and the number of shares of each may be fixed at the time the stock purchase contracts are issued or may be determined by reference to a specific formula set forth in the stock purchase contracts. The stock purchase contracts may be issued separately or as part of units, often known as stock purchase units, consisting of a stock purchase contract and any combination of:

•

debt securities, or



•

debt obligations of third parties, including U.S. Treasury securities,

which may secure the holders' obligations to purchase the common stock or preferred stock under the stock purchase contracts. The stock purchase contracts may require us to make periodic payments to the holders of the stock purchase units or vice versa, and these payments may be unsecured or pre-funded on some basis. The stock purchase contracts may require holders to secure their obligations under those contracts in a specified manner.

        The applicable prospectus supplement will describe the terms of the stock purchase contracts and stock purchase units, including, if applicable, collateral arrangements relating thereto.

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PLAN OF DISTRIBUTION

        We may offer and sell the securities being offered hereby in one or more of the following ways from time to time:

•

to underwriters or dealers for resale to the public or to institutional investors;



•

directly to institutional investors;



•

directly to a limited number of purchasers or to a single purchaser;



•

through agents to the public or to institutional investors; or



•

through a combination of any of these methods of sale.

        The prospectus supplement with respect to each series of securities will state the terms of the offering of the securities, including:

•

the offering terms, including the name or names of any underwriters, dealers or agents;



•

the purchase price of the securities and the net proceeds to be received by us from the sale;



•

any underwriting discounts or agency fees and other items constituting underwriters' or agents' compensation;



•

any public offering price;



•

any discounts or concessions allowed or reallowed or paid to dealers; and



•

any securities exchange on which the securities may be listed.

        If we use underwriters or dealers in the sale, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions, including:

•

privately negotiated transactions;



•

at a fixed public offering price or prices, which may be changed;



•

in "at the market offerings" within the meaning of Rule 415(a)(4) of the Securities Act;



•

at prices related to prevailing market prices; or



•

at negotiated prices.

        Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        If underwriters are used in the sale of any securities, the securities may be offered either to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters. Generally, the underwriters' obligations to purchase the securities will be subject to certain conditions precedent. The underwriters will be obligated to purchase all of the securities if they purchase any of the securities.

        We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of common shares, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of common shares. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be

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identified in the applicable prospectus supplement or a post-effective amendment to this registration statement.

        If indicated in an applicable prospectus supplement, we may sell the securities through agents from time to time. The applicable prospectus supplement will name any agent involved in the offer or sale of the securities and any commissions we pay to them. Generally, any agent will be acting on a best efforts basis for the period of its appointment. We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in the applicable prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The delayed delivery contracts will be subject only to those conditions set forth in the applicable prospectus supplement, and the applicable prospectus supplement will set forth any commissions we pay for solicitation of these delayed delivery contracts.

        Offered securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreements, if any, with us and its compensation will be described in the applicable prospectus supplement.

        Agents, underwriters and other third parties described above may be entitled to indemnification by us against certain civil liabilities under the Securities Act, or to contribution with respect to payments which the agents or underwriters may be required to make in respect thereof. Agents, underwriters and such other third parties may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

        Each series of securities will be a new issue of securities and will have no established trading market, other than our common stock, which is listed on the NASDAQ Global Select Market. Any common stock sold will be listed on the NASDAQ Global Select Market, upon official notice of issuance. The securities other than the common stock may or may not be listed on a national securities exchange and no assurance can be given that there will be a secondary market for any such securities or liquidity in the secondary market if one develops. Any underwriters to whom securities are sold by us for public offering and sale may make a market in the securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice.

LEGAL MATTERS

        In connection with particular offerings of the securities in the future, unless otherwise stated in the applicable prospectus supplement, the validity of those securities will be passed upon for us by Davis Polk & Wardwell LLP, New York, New York. Any underwriters will also be advised about legal matters by their own counsel, which will be named in the prospectus supplement.

EXPERTS

        The consolidated financial statements of Gilead Sciences, Inc. appearing in Gilead Sciences, Inc.'s Annual Report (Form 10-K) for the year ended December 31, 2019 (including the schedule appearing therein), and the effectiveness of Gilead Sciences, Inc.'s internal control over financial reporting as of December 31, 2019, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements and schedule are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution

        The following table sets forth the expenses, other than underwriting discounts and commissions, payable by the registrant in connection with the sale of the securities being registered hereby. All amounts, except the Securities and Exchange Commission (the "SEC") registration fee, are estimates:

Item 15.    Indemnification of Directors and Officers

        The Delaware General Corporation Law (the "DGCL") authorizes corporations to limit or eliminate the personal liability of directors to corporations and their stockholders for monetary damages for breaches of directors' fiduciary duties. The registrant's restated certificate of incorporation includes a provision that eliminates the personal liability of directors for monetary damages for breach of fiduciary duty as a director to the fullest extent permitted by Delaware law.

        Section 102(b)(7) of the DGCL provides that a corporation may eliminate or limit the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director; provided that such provision shall not eliminate or limit the liability of a director (i) for any breach of the director's duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL (regarding, among other things, the payment of unlawful dividends) or (iv) for any transaction from which the director derived an improper personal benefit.

        In addition, the registrant's restated certificate of incorporation and its amended and restated bylaws provide for indemnification of directors and executive officers in defending an action to the fullest extent and in the manner not prohibited by the DGCL or any other applicable law, provided, however, that the corporation may modify the extent of such indemnification by individual contracts with its directors and executive officers; and, provided, further, that the registrant shall not be required to indemnify any director or executive officer in connection with any proceeding (or part thereof)

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initiated by such person unless (i) such indemnification is expressly required to be made by law, (ii) the proceeding was authorized by the board of directors of the registrant, (iii) such indemnification is provided by the registrant, in its sole discretion, pursuant to the powers vested in the registrant under the DGCL or any other applicable law or (iv) such indemnification is required to be made pursuant to the provisions of the restated certificate of incorporation.

        In addition, the registrant shall advance to any person who was or is a party or is threatened to be made a party to any threatened, pending, or completed action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he is or was a director or executive officer, of the registrant, or is or was serving at the request of the registrant as a director or executive officer of another corporation, partnership, joint venture, trust or other enterprise, prior to the final disposition of the proceeding, promptly following request therefor, all expenses incurred by any director or executive officer in connection with such proceeding upon receipt of an undertaking by or on behalf of such person to repay said amounts if it should be determined ultimately that such person is not entitled to be indemnified under our bylaws or otherwise. Notwithstanding the foregoing, unless otherwise determined pursuant to the registrant's amended and restated bylaws, no advance shall be made by the registrant to an executive officer of the registrant (except by reason of the fact that such executive officer is or was a director of the registrant in which event this paragraph shall not apply) in any action, suit or proceeding, whether civil, criminal, administrative or investigative, if a determination is reasonably and promptly made (i) by the board of directors by a majority vote of a quorum consisting of directors who were not parties to the proceeding, or (ii) if such quorum is not obtainable, or, even if obtainable, a quorum of disinterested directors so directs, by independent legal counsel in a written opinion, that the facts known to the decision-making party at the time such determination is made demonstrate clearly and convincingly that such person acted in bad faith or in a manner that such person did not believe to be in opposition to the best interests of the registrant.

        Section 145(a) of the DGCL empowers a corporation to indemnify any director, officer, employee, or agent, or former director, officer, employee, or agent, who was or is a party or is threatened to be made a party to any threatened, pending, or completed action, suit, or proceeding, whether civil, criminal, administrative, or investigative (other than an action by or in the right of the corporation) by reason of his service as a director, officer, employee, or agent of the corporation, or his service, at the corporation's request, as a director, officer, employee, or agent of another corporation or enterprise, against expenses (including attorneys' fees), judgments, fines, and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit, or proceeding, provided that such director or officer acted in good faith and in a manner reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding; provided that such director or officer had no reasonable cause to believe his conduct was unlawful.

        Section 145(b) of the DGCL empowers a corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending, or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that such person is or was a director, officer, employee, or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee, or agent of another enterprise, against expenses (including attorneys' fees) actually and reasonably incurred in connection with the defense or settlement of such action or suit; provided that such director or officer acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification may be made in respect of any claim, issue, or matter as to which such director or officer shall have been adjudged to be liable to the corporation unless and only to the extent that the Delaware Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such director or officer is fairly and reasonably entitled to indemnity for such expenses which the court shall deem proper. Notwithstanding the preceding sentence, except as otherwise provided in the

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bylaws, we shall be required to indemnify any such person in connection with a proceeding (or part thereof) commenced by such person only if the commencement of such proceeding (or part thereof) by any such person was authorized by the board.

        The registrant has entered into indemnification agreements with substantially all of its directors and officers which provide indemnification under certain circumstances for acts and omissions which may not be covered by any directors' and officers' liability insurance.

Item 16.    Exhibits

        A list of exhibits filed herewith is contained in the exhibit index that immediately precedes such exhibits and is incorporated herein by reference.

Item 17.    Undertakings

        The undersigned registrant hereby undertakes:

(1)

To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:



(i)

To include any prospectus required by Section 10(a)(3) of the Securities Act;



(ii)

To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and



(iii)

To include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement; provided, however, that paragraphs (i), (ii) and (iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), that are incorporated by reference in this registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of this registration statement.



(2)

That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.



(3)

To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

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(4)

That, for the purpose of determining liability under the Securities Act to any purchaser:



(i)

Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of this registration statement as of the date the filed prospectus was deemed part of and included in this registration statement; and



(ii)

Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by Section 10 (a) of the Securities Act shall be deemed to be part of and included in this registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which the prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof; provided, however, that no statement made in a registration statement or prospectus that is part of this registration statement or made in a document incorporated or deemed incorporated by reference into this registration statement or prospectus that is part of this registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in this registration statement or prospectus that was part of this registration statement or made in any such document immediately prior to such effective date.



(5)

(a) That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:



(i)

Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;



(ii)

Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;



(iii)

The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and



(iv)

Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.



(b)

The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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(c)

The undersigned registrant hereby undertakes to supplement the prospectus, after the expiration of the subscription period, to set forth the results of the subscription offer, the transactions by the underwriters during the subscription period, the amount of unsubscribed securities to be purchased by the underwriters, and the terms of any subsequent reoffering thereof. If any public offering by the underwriters is to be made on terms differing from those set forth on the cover page of the prospectus, a post-effective amendment will be filed to set forth the terms of such offering.



(d)

The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act") in accordance with the rules and regulations prescribed by the SEC under Section 305(b)(2) of the Trust Indenture Act.

        Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question as to whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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EXHIBIT INDEX

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Foster City, State of California, on August 7, 2020.

        Each person whose signature to this registration statement appears below hereby constitutes and appoints each of Daniel P. O'Day, Andrew D. Dickinson and Brett A. Pletcher, and each or any one of them, as such person's true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for such person and in such person's name, place and stead, in any and all capacities, to sign any and all amendments to the registration statement, including post-effective amendments, and registration statements filed pursuant to Rule 462 under the Securities Act of 1933, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, and does hereby grant unto each said attorney-in-fact and agent full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as such person might or could do in person, hereby ratifying and confirming all that each said attorney-in-fact and agents or any of them, or their substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

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Exhibit 5.1 and 23.2

OPINION OF DAVIS POLK & WARDWELL LLP

August 7, 2020

Gilead Sciences, Inc.
333 Lakeside Drive
Foster City, California 94404

Ladies and Gentlemen:

        Gilead Sciences, Inc., a Delaware corporation (the "Company") is filing with the Securities and Exchange Commission a Registration Statement on Form S-3 (the "Registration Statement") for the purpose of registering under the Securities Act of 1933, as amended (the "Securities Act"), (a) shares of common stock, par value $0.001 per share (the "Common Stock") of the Company; (b) shares of preferred stock, par value $0.001 per share (the "Preferred Stock") of the Company; (c) the Company's senior debt securities (the "Debt Securities"), which may be issued pursuant to a senior debt indenture dated as of filing, between the Company and Wells Fargo Bank, National Association, as trustee (the "Trustee") (the "Indenture"); (d) warrants of the Company (the "Warrants"), which may be issued under one or more warrant agreements (each, a "Warrant Agreement") to be entered into between the Company and the warrant agent to be named therein (the "Warrant Agent"); (e) stock purchase contracts (the "Purchase Contracts") which may be issued under one or more purchase contract agreements (each, a "Purchase Contract Agreement") to be entered into between the Company and the purchase contract agent to be named therein (the "Purchase Contract Agent"); (f) stock purchase units (the "Units") to be issued under one or more unit agreements to be entered into among the Company, a bank or trust company, as unit agent (the "Unit Agent"), and the holders from time to time of the Units (each such unit agreement, a "Unit Agreement"); (g) depositary shares representing fractional interests in shares or multiple shares of the Preferred Stock (the "Depositary Shares"), which may be issued under one or more preferred stock depositary agreements (each, a "Depositary Agreement") to be entered into between the Company and the preferred stock depositary to be named therein (the "Depositary") and (h) subscription rights ("Rights") which may be issued pursuant to a subscription rights agreement (the "Rights Agreement") to be entered into between the Company and the subscription agent to be named therein (the "Rights Agent").

        We, as your counsel, have examined originals or copies of such documents, corporate records, certificates of public officials and other instruments as we have deemed necessary or advisable for the purpose of rendering this opinion.

        In rendering the opinions expressed herein, we have, without independent inquiry or investigation, assumed that (i) all documents submitted to us as originals are authentic and complete, (ii) all documents submitted to us as copies conform to authentic, complete originals, (iii) all documents filed as exhibits to the Registration Statement that have not been executed will conform to the forms thereof, (iv) all signatures on all documents that we reviewed are genuine, (v) all natural persons executing documents had and have the legal capacity to do so, (vi) all statements in certificates of public officials and officers of the Company that we reviewed were and are accurate and (vii) all representations made by the Company as to matters of fact in the documents that we reviewed were and are accurate.

        Based upon the foregoing, and subject to the additional assumptions and qualifications set forth below, we advise you that, in our opinion:

1.

When the necessary corporate action on the part of the Company has been taken to authorize the issuance and sale of such shares of Common Stock proposed to be sold by the Company, and when such shares of Common Stock are issued and delivered in accordance with the applicable underwriting or other agreement against payment therefor (in excess of par value thereof) or upon conversion or exercise of any security offered under the Registration Statement (the "Offered Security"), in accordance with the terms of such Offered Security or

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the instrument governing such Offered Security providing for such conversion or exercise as approved by the Board of Directors of the Company, for the consideration approved by such Board of Directors (which consideration is not less than the par value of the Common Stock), such shares of Common Stock will be validly issued, fully-paid and non-assessable.

2.

Upon designation of the relative rights, preferences and limitations of any series of Preferred Stock by the Board of Directors of the Company and the proper filing with the Secretary of State of the State of Delaware of a Certificate of Designation relating to such series of Preferred Stock, all necessary corporate action on the part of the Company will have been taken to authorize the issuance and sale of such series of Preferred Stock proposed to be sold by the Company, and when such shares of Preferred Stock are issued and delivered in accordance with the applicable underwriting or other agreement against payment therefor (in excess of par value thereof), such shares of Preferred Stock will be validly issued, fully paid and non-assessable.



3.

When the Indenture and any supplemental indenture to be entered into in connection with the issuance of any Debt Securities have been duly authorized, executed and delivered by the Trustee and the Company; the specific terms of a particular series of Debt Securities have been duly authorized and established in accordance with the Indenture; and such Debt Securities have been duly authorized, executed, authenticated, issued and delivered in accordance with the Indenture and the applicable underwriting or other agreement against payment therefor, such Debt Securities will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability, provided that we express no opinion as to the enforceability of any waiver of rights under any usury or stay law.



4.

When the Warrant Agreement to be entered into in connection with the issuance of any Warrants has been duly authorized, executed and delivered by the Warrant Agent and the Company; the specific terms of the Warrants have been duly authorized and established in accordance with the Warrant Agreement; and such Warrants have been duly authorized, executed, issued and delivered in accordance with the Warrant Agreement and the applicable underwriting or other agreement against payment therefor, such Warrants will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability.



5.

When the Purchase Contract Agreement to be entered into in connection with the issuance of any Purchase Contracts has been duly authorized, executed and delivered by the Purchase Contract Agent and the Company; the specific terms of the Purchase Contracts have been duly authorized and established in accordance with the Purchase Contract Agreement; and such Purchase Contracts have been duly authorized, executed, issued and delivered in accordance with the Purchase Contract Agreement and the applicable underwriting or other agreement against payment therefor, such Purchase Contracts will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability.



6.

When the Unit Agreement to be entered into in connection with the issuance of any Units has been duly authorized, executed and delivered by the Unit Agent and the Company; the specific terms of the Units have been duly authorized and established in accordance with the Unit Agreement; and such Units have been duly authorized, executed, issued and delivered in accordance with the Unit Agreement and the applicable underwriting or other agreement

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against payment therefor, such Units will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability.

7.

When the Depositary Agreement to be entered into in connection with the issuance of any Depositary Shares has been duly authorized, executed and delivered by the Depositary and the Company; the specific terms of the Depositary Shares have been duly authorized and established in accordance with the Depositary Agreement; and such Depositary Shares have been duly authorized, executed, issued and delivered in accordance with the Depositary Agreement and the applicable underwriting or other agreement against payment therefor, such Depositary Shares will constitute legal and valid interests in the corresponding shares of Preferred Stock, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability.



8.

When the Rights Agreement to be entered into in connection with the issuance of any Rights has been duly authorized, executed and delivered by the Rights Agent and the Company; the specific terms of the Rights have been duly authorized and established in accordance with the Rights Agreement; and such Rights have been duly authorized, executed, issued and delivered in accordance with the Rights Agreement and the applicable underwriting or other agreement against payment therefor, such Rights will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally, concepts of reasonableness and equitable principles of general applicability.

        In connection with the opinions expressed above, we have assumed that, at or prior to the time of the delivery of any such security, (i) the Board of Directors of the Company shall have duly established the terms of such security and duly authorized the issuance and sale of such security and such authorization shall not have been modified or rescinded; (ii) the Company shall remain, validly existing as a corporation in good standing under the laws of the State of Delaware; (iii) the Registration Statement shall have become effective and such effectiveness shall not have been terminated or rescinded; (iv) the Indenture, the Debt Securities, the Warrant Agreement, the Purchase Contract Agreement, the Unit Agreement, the Depositary Agreement and the Rights Agreement are each valid, binding and enforceable agreements of each party thereto (other than as expressly covered above in respect of the Company); and (v) there shall not have occurred any change in law affecting the validity or enforceability of such security. We have also assumed that (i) the terms of any security whose terms are established subsequent to the date hereof and the issuance, execution, delivery and performance by the Company of any such security (a) require no action by or in respect of, or filing with, any governmental body, agency or official and (b) do not contravene, or constitute a default under, any provision of applicable law or public policy or regulation or any judgment, injunction, order or decree or any agreement or other instrument binding upon the Company and (ii) any Warrant Agreement, Purchase Contract Agreement, Unit Agreement, Depositary Agreement and Rights Agreement will be governed by the laws of the State of New York.

        We are members of the Bar of the State of New York and the foregoing opinion is limited to the laws of the State of New York and the General Corporation Law of the State of Delaware.

        We hereby consent to the filing of this opinion as an exhibit to the Registration Statement referred to above and further consent to the reference to our name under the caption "Legal Matters" in the prospectus, which is a part of the Registration Statement. In giving this consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

Very truly yours,

/s/ Davis Polk & Wardwell LLP

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Exhibit 5.1 and 23.2

OPINION OF DAVIS POLK & WARDWELL LLP

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

        We consent to the reference to our firm under the caption "Experts" in the Registration Statement (Form S-3) and related Prospectus of Gilead Sciences, Inc. for the registration of debt securities, common stock, preferred stock, depositary shares, warrants, subscription rights, stock purchase contracts and stock purchase units and to the incorporation by reference therein of our reports dated February 24, 2020, with respect to the consolidated financial statements and schedule of Gilead Sciences, Inc., and the effectiveness of internal control over financial reporting of Gilead Sciences, Inc., included in its Annual Report (Form 10-K) for the year ended December 31, 2019, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP
San Jose, California
August 6, 2020

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

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Exhibit 25.1

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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FORM T-1
STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

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        o CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE
PURSUANT TO SECTION 305(b) (2)

WELLS FARGO BANK, NATIONAL ASSOCIATION
(Exact name of trustee as specified in its charter)

Wells Fargo & Company
Law Department, Trust Section
MAC N9305-175
Sixth Street and Marquette Avenue, 17^th Floor
Minneapolis, Minnesota 55479
(612) 667-4608
(Name, address and telephone number of agent for service)

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GILEAD SCIENCES, INC.
(Exact name of obligor as specified in its charter)

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Senior Debt Securities
(Title of the indenture securities)

   

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Item 1.    General Information. Furnish the following information as to the trustee:

(a)

Name and address of each examining or supervising authority to which it is subject.

Comptroller of the Currency
Treasury Department
Washington, D.C.

Federal Deposit Insurance Corporation
Washington, D.C.

Federal Reserve Bank of San Francisco
San Francisco, California 94120

(b)

Whether it is authorized to exercise corporate trust powers.

The trustee is authorized to exercise corporate trust powers.

Item 2.    Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.

        None with respect to the trustee.

        No responses are included for Items 3-14 of this Form T-1 because the obligor is not in default as provided under Item 13.

Item 15.    Foreign Trustee. Not applicable.

Item 16.    List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.

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SIGNATURE

        Pursuant to the requirements of the Trust Indenture Act of 1939, as amended, the trustee, Wells Fargo Bank, National Association, a national banking association organized and existing under the laws of the United States of America, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of Los Angeles and State of California on the 29th day of July, 2020.

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EXHIBIT 6

July 29, 2020

Securities and Exchange Commission
Washington, D.C. 20549

Gentlemen:

        In accordance with Section 321(b) of the Trust Indenture Act of 1939, as amended, the undersigned hereby consents that reports of examination of the undersigned made by Federal, State, Territorial, or District authorities authorized to make such examination may be furnished by such authorities to the Securities and Exchange Commission upon its request therefor.

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Exhibit 7

Consolidated Report of Condition of
Wells Fargo Bank National Association
of 101 North Phillips Avenue, Sioux Falls, SD 57104
And Foreign and Domestic Subsidiaries,
at the close of business March 31, 2020, filed in accordance with 12 U.S.C. §161 for National Banks.

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        I, John R. Shrewsberry, Sr. EVP & CFO of the above-named bank do hereby declare that this Report of Condition has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true to the best of my knowledge and belief.

        We, the undersigned directors, attest to the correctness of this Report of Condition and declare that it has been examined by us and to the best of our knowledge and belief has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true and correct.

Directors
Maria R. Morris
Theodore F. Craver, Jr.
Juan A. Pujadas

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Exhibit 25.1

Item 1. General Information. Furnish the following information as to the trustee
Item 2. Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.
Item 15. Foreign Trustee. Not applicable.
Item 16. List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.

Exhibit 7
Consolidated Report of Condition of Wells Fargo Bank National Association of 101 North Phillips Avenue, Sioux Falls, SD 57104 And Foreign and Domestic Subsidiaries, at the close of business March 31, 2020, filed in accordance with 12 U.S.C. §161 for National Banks.

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