Gary K. Lee - 09 Feb 2026 Form 4 Insider Report for Lyell Immunopharma, Inc. (LYEL)

Role: Chief Scientific Officer
Signature: /s/ Mark Meltz, Attorney-in-Fact
Issuer symbol: LYEL
Transactions as of: 09 Feb 2026
Net transactions value: -$3,399
Form type: 4
Filing time: 11 Feb 2026, 21:04:20 UTC
Previous filing: 12 Nov 2025
Next filing: 12 Feb 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Lee Gary K.	Chief Scientific Officer	C/O LYELL IMMUNOPHARMA, INC., 201 HASKINS WAY, SOUTH SAN FRANCISCO	/s/ Mark Meltz, Attorney-in-Fact	11 Feb 2026	0001907345

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	LYEL	Common Stock	Award	$0	+4,000	+27%	$0.000000	18,756	09 Feb 2026	Direct	F1, F2
transaction	LYEL	Common Stock	Sale	$3,399	-147	-0.78%	$23.12	18,609	10 Feb 2026	Direct	F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	LYEL	Option (right to buy)	Award	$0	+50,000		$0.000000	50,000	10 Feb 2026	Common Stock	50,000	$23.71	Direct	F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Pursuant to performance-based restricted stock units granted to the reporting person on February 9, 2024, 4,000 shares were issued on the Transaction Date upon the achievement of certain performance criteria certified by the compensation committee of the Issuer's board of directors on the Transaction Date.
F2	Includes 390 shares acquired on November 18, 2025 under the Issuer's 2021 Employee Stock Purchase Plan.
F3	Shares automatically sold to cover tax withholding obligation from settlement of vested restricted stock units.
F4	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.