SCHEDULE 13D/A 0001123292-25-000309 0000882095 XXXXXXXX LIVE 6 Common Stock, par value $0.0001 11/03/2025 false 0001724521 03969F109 Arcus Biosciences, Inc.

3928 Point Eden Way Hayward CA 94545

Gilead Sciences, Inc. 650-574-3000 333 Lakeside Drive Foster City CA 94404 0000882095 GILEAD SCIENCES, INC. OO DE 31424760 0 31424760 0 31424760 N 25.6 CO The number of shares reported in rows 7, 9, and 11 consists of (i) 2,200,000 shares of the common stock, par value $0.0001 per share (the "Common Stock"), of Arcus Biosciences, Inc. (the "Issuer") purchased in the 2020 Public Offering, (ii) the initial purchase of 5,963,029 shares of Common Stock pursuant to the Purchase Agreement, (iii) the subsequent purchase of 5,650,000 shares of Common Stock pursuant to the Amended and Restated Purchase Agreement, (iv) the subsequent purchase of 1,010,000 shares of Common Stock pursuant to the Second Amended and Restated Purchase Agreement, (v) the subsequent purchase of 15,238,095 shares of Common Stock of the Issuer pursuant to the Third Amended and Restated Purchase Agreement, and (vi) the subsequent purchase of 1,363,636 shares of Common Stock pursuant to the Public Offering. The percent reported in row 13 is calculated based upon 122,856,086 shares of Common Stock issued and outstanding, as reported in the prospectus supplement filed by the Issuer with the Securities and Exchange Commission (the "SEC") on October 31, 2025. Common Stock, par value $0.0001 Arcus Biosciences, Inc. 3928 Point Eden Way Hayward CA 94545 This Amendment No. 6 (the "Amendment") amends the initial Schedule 13D filed by the Reporting Person on July 17, 2020, as amended by Amendment No. 1 to Schedule 13D filed with the SEC by the Reporting Person on February 2, 2021, Amendment No. 2 to Schedule 13D filed with the SEC by the Reporting Person on July 6, 2023, Amendment No. 3 to Schedule 13D filed with the SEC by the Reporting Person on January 31, 2024, Amendment No. 4 to Schedule 13D filed with the SEC by the Reporting Person on March 5, 2025 and Amendment No. 5 to Schedule 13D filed with the SEC by the Reporting Person on July 15, 2025 (the "Original Schedule 13D," and as amended by Amendment No. 6, the "Schedule 13D"). Capitalized terms used but not defined in this Amendment shall have the same meanings ascribed to them in the Original Schedule 13D. Item 5(a) of the Schedule 13D is hereby amended and restated to read as follows: Number of shares of Common Stock beneficially owned: Gilead - 31,424,760 shares Jeffrey A. Bluestone - 10,750 shares Percent of class: Gilead - 25.6% Jeffrey A. Bluestone - 0.01% The number of shares of Common Stock beneficially owned by Gilead consists of (i) 2,200,000 shares of Common Stock purchased in the 2020 Public Offering, (ii) the initial purchase of 5,963,029 shares of Common Stock pursuant to the Purchase Agreement, (iii) the subsequent purchase of 5,650,000 shares of Common Stock pursuant to the Amended and Restated Purchase Agreement, (iv) the subsequent purchase of 1,010,000 shares of Common Stock pursuant to the Second Amended and Restated Purchase Agreement, (v) the subsequent purchase of 15,238,095 shares of Common Stock pursuant to the Third Amended and Restated Purchase Agreement, and (vi) the subsequent purchase of 1,363,636 shares of Common Stock pursuant to the Public Offering. The number of shares of Common Stock beneficially owned by Mr. Bluestone consists of options to purchase 10,750 shares of Common Stock exercisable within 60 days. The percentage ownership for Gilead was calculated based upon 122,856,086 shares of common stock of the Issuer issued and outstanding, as reported in the prospectus supplement filed by the Issuer with the SEC on October 31, 2025. The percentage ownership for Mr. Bluestone was calculated based upon 122,866,836 shares of Common Stock issued and outstanding, based on 122,856,086 shares of Common Stock issued and outstanding and assuming the immediate exercise in full by Mr. Bluestone of his options. To the best knowledge of the Reporting Person, none of the individuals listed on Schedule I beneficially owns any of the Issuer's Common Stock, except Mr. Bluestone, who has received options to purchase shares of Common Stock in partial payment for his service on the Issuer's Scientific Advisory Board. Item 5(b) of the Schedule 13D is hereby amended and restated to read as follows: Number of shares as to which such person has: (i) Sole power to vote or to direct the vote: Gilead - 31,424,760 shares Jeffrey A. Bluestone - 10,750 shares (ii) Shared power to vote or to direct the vote: Gilead - 0 shares Jeffrey A. Bluestone - 0 shares (iii) Sole power to dispose or to direct the disposition of: Gilead - 31,424,760 shares Jeffrey A. Bluestone - 10,750 shares (iv) Shared power to dispose or to direct the disposition of: Gilead - 0 shares Jeffrey A. Bluestone - 0 shares GILEAD SCIENCES, INC. /s/ Andrew D. Dickinson 11/05/2025