WILLIAM J. NEWELL - 04 Mar 2025 Form 4 Insider Report for SUTRO BIOPHARMA, INC. (STRO)

Role: CEO, Director
Signature: /s/ Edward C. Albini as attorney-in-fact for William J. Newell
Issuer symbol: STRO
Transactions as of: 04 Mar 2025
Net transactions value: -$15,813
Form type: 4
Filing time: 06 Mar 2025, 16:09:29 UTC
Previous filing: 04 Mar 2025
Next filing: 07 Mar 2025
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	STRO	Common Stock	Options Exercise	$0	+31,125	+12%	$0.000000	291,625	04 Mar 2025	Direct
transaction	STRO	Common Stock	Tax liability	$15,813	-11,136	-3.8%	$1.42	280,489	04 Mar 2025	Direct	F1
holding	STRO	Common Stock						116,525	04 Mar 2025	By William J. Newell Family Trust DTD 03/15/2019	F2

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	STRO	Restricted Stock Unit (RSU)	Options Exercise	$0	-31,125	-50%	$0.000000	31,125	04 Mar 2025	Common Stock	31,125		Direct	F3, F4

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

Explanation of Responses:

Id	Content
F1	Represents the number of shares of Common Stock that have been withheld by the issuer to satisfy its income tax withholding and remittance obligations in connection with the net settlement of restricted stock units; does not represent a sale by the reporting person.
F2	The securities are held of record by the reporting person as trustee of the William J. Newell Family Trust DTD 03/15/2019.
F3	Each RSU represents a contingent right to receive one (1) share of the issuer's Common Stock upon settlement.
F4	The RSUs vest as to 1/4th of the total shares annually beginning on March 4, 2023, subject to continued service through each vesting date.