X0609 4 2026-06-10 0001806952 Lyell Immunopharma, Inc. LYEL 0001411874 FRIEDMAN CATHY false C/O LYELL IMMUNOPHARMA, INC. 201 HASKINS WAY, SUITE 101 SOUTH SAN FRANCISCO CA 94080 true false false false 0 Common Stock 11818 I MSL FBO J DUANE & C FRIEDMAN TTEE DUANE FAMILY TRUST Common Stock 5000 I The Duane Irrevocable Trust 2020 Option (right to buy) 13.22 2026-06-10 4 A 0 9250 0 A 2036-06-09 Common Stock 9250 9250 D On May 30, 2025, the Issuer effected a 1-for-20 reverse stock split of its common stock. All share and amounts reported herein reflect the reverse stock split. The Reporting Person is a trustee of MSL FBO J DUANE & C FRIEDMAN TTEE DUANE FAMILY TRUST ("Duane Family Trust") and therefore may be deemed to share the power to direct the disposition and vote of the shares held by the Duane Family Trust. The Reporting Person disclaims beneficial ownership of all shares held by Duane Family Trust except to any pecuniary interest therein. The Reporting Person is a trustee of The Duane Irrevocable Trust 2020 ("Duane Irrevocable Trust") and therefore may be deemed to share the power to direct the disposition and vote of the shares held by the Duane Irrevocable Trust. The Reporting Person disclaims beneficial ownership of all shares held by Duane Irrevocable Trust except to any pecuniary interest therein. The option shares shall vest on the earlier of (a) the date of the next annual meeting of the stockholders that occurs following June 10, 2026 (or the date immediately prior to such date if the Reporting Person's service as a director ends at such annual meeting due to the Reporting Person's failure to be reelected or the Reporting Person not standing for re-election); or (b) the first anniversary of June 10, 2026, subject to the Reporting Person providing continuous service through such date. /s/ Mark Meltz, Attorney-in-Fact 2026-06-11