David Pauling - Apr 4, 2025 Form 3 Insider Report for SUTRO BIOPHARMA, INC. (STRO)

Role: Chief Admin. Ofcr. & GC
Signature: /s/ David Pauling
Stock symbol: STRO
Transactions as of: Apr 4, 2025
Transactions value $: $0
Form type: 3
Date filed: 4/8/2025, 04:03 PM
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
holding	STRO	Common Stock						98.8K	Apr 4, 2025	Direct

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
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	1.38K	$14.16	Direct	F1
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	13.1K	$15.00	Direct	F2
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	23K	$6.55	Direct	F3
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	40K	$21.11	Direct	F4
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	28K	$8.17	Direct	F5
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	30K	$5.79	Direct	F6
holding	STRO	Stock Option (Right to Buy)							Apr 4, 2025	Common Stock	44K	$4.54	Direct	F7
holding	STRO	Restricted Stock Units							Apr 4, 2025	Common Stock	6.75K		Direct	F8, F9
holding	STRO	Restricted Stock Units							Apr 4, 2025	Common Stock	10K		Direct	F9, F10
holding	STRO	Restricted Stock Units							Apr 4, 2025	Common Stock	25.3K		Direct	F9, F11

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

Explanation of Responses:

Id	Content
F1	The option is fully vested. Pursuant to the terms of the reporting person's award agreement with the issuer, the award became fully vested on February 24, 2020.
F2	The option is fully vested. Pursuant to the terms of the reporting person's award agreement with the issuer, the award became fully vested on September 26, 2022.
F3	The option is fully vested. Pursuant to the terms of the reporting person's award agreement with the issuer, the award became fully vested on March 18, 2024.
F4	The option is fully vested. Pursuant to the terms of the reporting person's award agreement with the issuer, the award became fully vested on March 5, 2025.
F5	The option vested or vests ratably as to approximately 2.0833% of the total award monthly, beginning on April 4, 2022, with 100% of the award being vested and exercisable on March 4, 2026, subject to the reporting person's provision of service to the issuer on each vesting date.
F6	The option vested or vests ratably as to approximately 2.0833% of the total award monthly, beginning on April 1, 2023, with 100% of the award being vested and exercisable on March 1, 2027, subject to the reporting person's provision of service to the issuer on each vesting date.
F7	The option vested or vests ratably as to approximately 2.0833% of the total award monthly, beginning on April 1, 2024, with 100% of the award being vested and exercisable on March 1, 2028, subject to the reporting person's provision of service to the issuer on each vesting date.
F8	The award vests as to 1/4th of the total award annually beginning on March 4, 2023, subject to the reporting person's provision of service to the issuer on each vesting date.
F9	Each restricted stock unit represents a contingent right to receive one (1) share of the issuer's Common Stock upon settlement
F10	The award vests as to 1/4th of the total award annually beginning on March 1, 2024, subject to the reporting person's provision of service to the issuer on each vesting date.
F11	The award vests as to 1/4th of the total award annually beginning on March 1, 2025, subject to the reporting person's provision of service to the issuer on each vesting date.