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

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: STRO
Reported as of: 04 Mar 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 06 Mar 2026, 16:21:10 UTC
Prior SEC filing: 03 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ David Pauling as attorney-in-fact

Key filing fact

Jane Chung filed Form 4 for SUTRO BIOPHARMA, INC. (STRO) on 06 Mar 2026.

Key facts

This page summarizes Jane Chung's Form 4 filing for SUTRO BIOPHARMA, INC. (STRO).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 06 Mar 2026, 16:21.

Change

Previous filing in this sequence was filed on 03 Mar 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001872398 Primary reporting owner

Chung Jane

Relationship: Chief Executive Officer, Director
Address: C/O SUTRO BIOPHARMA, INC., 111 OYSTER POINT BLVD., SOUTH SAN FRANCISCO
Signature: /s/ David Pauling as attorney-in-fact
Signature date: 06 Mar 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

STRO transaction

Common Stock

Options Exercise

Transaction value
Shares: +788
Change %: +3.8%
Price: $0.000000^*
Shares after: 21,567
Date: 04 Mar 2026
Ownership: Direct

STRO transaction

Common Stock

Tax liability

Transaction value
Shares: -282
Change %: -1.3%
Price: $21.31^*
Shares after: 21,285
Date: 04 Mar 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

STRO transaction Derivative

Restricted Stock Units (RSUs)

Options Exercise

Transaction value
Shares: -788
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 04 Mar 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 788
Exercise price
Footnotes: F2, F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote 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.

Footnote F2

Each RSU represents a contingent right to receive one (1) share of the Issuer's Common Stock upon settlement.

Footnote 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.