David Pauling - 04 Mar 2026 Form 4 Insider Report for SUTRO BIOPHARMA, INC. (STRO)

Role: Chief Admin. Ofcr. & GC
Signature: /s/ David Pauling
Issuer symbol: STRO
Transactions as of: 04 Mar 2026
Net transactions value: $0
Form type: 4
Filing time: 06 Mar 2026, 16:25:03 UTC
Previous filing: 03 Mar 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Pauling David	Chief Admin. Ofcr. & GC	C/O SUTRO BIOPHARMA, INC., 111 OYSTER POINT BLVD., SOUTH SAN FRANCISCO	/s/ David Pauling	06 Mar 2026	0002063633

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	STRO	Common Stock	Options Exercise		+675	+7.2%	$0.000000^*	10,025	04 Mar 2026	Direct
transaction	STRO	Common Stock	Tax liability		-277	-2.8%	$21.31^*	9,748	04 Mar 2026	Direct	F1

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 Units (RSUs)	Options Exercise		-675	-100%	$0.000000^*	0	04 Mar 2026	Common Stock	675		Direct	F2, F3

* 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	Each RSU represents a contingent right to receive one (1) share of the Issuer's Common Stock upon settlement.
F3	The RSUs vested or vest as to 1/4 of the total award annually, with the first tranche vested on March 4, 2023, subject to continued service through each vesting date.