X0508 4 2026-02-10 0001806952 Lyell Immunopharma, Inc. LYEL 0001959742 Shook David C/O LYELL IMMUNOPHARMA, INC. 201 HASKINS WAY, SUITE 101 SOUTH SAN FRANCISCO CA 94080 false true false false Chief Medical Officer 0 Common Stock 21900 D Option (right to buy) 23.71 2026-02-10 4 A 0 50000 0 A 2036-02-09 Common Stock 50000 50000 D Twelve and one-half percent (12.5%) of the total number of shares of Common Stock subject to the option will be vested and exercisable on the date that is six (6) months after February 9, 2026 (the "Vesting Commencement Date") and thereafter, an additional one fortyeighth (1/48th) of the shares will become vested and exercisable monthly on the same day as the Vesting Commencement Date (or, if there is no such corresponding day for a given month, on the last day of such month), until the option has become vested and exercisable with respect to one hundred percent (100%) of the shares, subject to the Reporting Person providing service to the Issuer through each applicable vesting date. /s/ Mark Meltz, Attorney-in-Fact 2026-02-11