Gilead Sciences, Inc.

Item 1.01. Entry into a Material Definitive Agreement. Supplemental Indenture On May 20, 2026, Gilead Sciences, Inc. (the “Company”) and Computershare Trust Company, National Association, as successor to Wells Fargo Bank, National Association, as trustee (the “Trustee” and, together with the Company, the “Parties”), entered into an Eleventh Supplemental Indenture (the “Eleventh Supplemental Indenture”) to the Indenture between the Parties, dated as of March 30, 2011 (the “Base Indenture”). The Eleventh Supplemental Indenture relates to the Company’s issuance of (a) $500,000,000 aggregate principal amount of the Company’s 4.250% Senior Notes due 2028 (the “2028 Notes”), (b) $1,000,000,000 aggregate principal amount of the Company’s 4.400% Senior Notes due 2029 (the “2029 Notes”), (c) $1,000,000,000 aggregate principal amount of the Company’s 4.600% Senior Notes due 2031 (the “2031 Notes”) and (d) $500,000,000 aggregate principal amount of the Company’s 4.900% Senior Notes due 2034 (the “2034 Notes” and, together with the 2028 Notes, the 2029 Notes and the 2031 Notes, the “Notes”). The Notes were sold in a public offering pursuant to the Company’s Registration Statement on Form S-3 (File No. 333-273745). The 2028 Notes will pay interest semi-annually at a rate of 4.250% per annum until May 20, 2028. The 2029 Notes will pay interest semi-annually at a rate of 4.400% per annum until May 20, 2029. The 2031 Notes will pay interest semi-annually at a rate of 4.600% per annum until May 20, 2031. The 2034 Notes will pay interest semi-annually at a rate of 4.900% per annum until May 20, 2034. The Company intends to use the net proceeds from the sale of the Notes for general corporate purposes, which may include funding for acquisitions, investments, strategic transactions or other business opportunities. The Base Indenture and the Eleventh Supplemental Indenture contain certain restrictions, including a limitation that restricts the Company’s ability and ability of certain of its subsidiaries to create or incur secured indebtedness, enter into sale and leaseback transactions and consolidate, merge or transfer all or substantially all of the Company’s assets and the assets of its subsidiaries, and also requires the Company to offer to repurchase the Notes upon certain change of control events. The Company may redeem some or all of the Notes at any time and from time to time at the applicable redemption prices described in the form of such notes. For a complete description of the terms and conditions of the Base Indenture, please refer to the Base Indenture, filed as Exhibit 4.1 to the Company’s Current Report on Form 8-K, filed with the Commission on April 1, 2011, and incorporated herein by reference. For a complete description of the terms and conditions of the Eleventh Supplemental Indenture and the Notes, please refer to the Eleventh Supplemental Indenture and the forms of each series of Notes, each of which is incorporated herein by reference and attached to this Current Report on Form 8-K as Exhibits 4.2, 4.3, 4.4, 4.5 and 4.6, respectively.

Item 2.03. Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth in Item 1.01 is incorporated herein by reference.

Item 8.01. Other Information. Underwriting Agreement On May 14, 2026, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with Barclays Capital Inc., BofA Securities, Inc. and Citigroup Global Markets Inc., as representatives of the several underwriters listed in Schedule 1 thereto, relating to the issuance and sale by the Company of the Notes. The description of the Underwriting Agreement contained herein is qualified in its entirety by reference to the Underwriting Agreement, which is filed as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference. The above-mentioned offering was made pursuant to the Company’s effective shelf registration statement on Form S-3 (File No. 333-273745). An opinion of counsel for the Company is filed as Exhibit 5.1 to this Current Report on Form 8-K.