Form: 4

Statement of changes in beneficial ownership of securities

March 7, 2022

FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MOLINA ARTURO MD
  2. Issuer Name and Ticker or Trading Symbol
SUTRO BIOPHARMA, INC. [STRO]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Medical Officer
(Last)
(First)
(Middle)
C/O SUTRO BIOPHARMA, INC., 111 OYSTER POINT BLVD.
3. Date of Earliest Transaction (Month/Day/Year)
03/04/2022
(Street)

SOUTH SAN FRANCISCO, CA 94080
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/05/2022   M   12,500 A (1) 42,091 D  
Common Stock 03/05/2022   F   4,355 (2) D $ 8.17 37,736 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (right to buy Common Stock) $ 8.17 03/04/2022   A   52,000     (3) 03/03/2032 Common Stock 52,000 $ 0 52,000 D  
Restricted Stock Unit (RSU) (1) 03/04/2022   A   39,000     (4) 03/04/2026 Common Stock 39,000 $ 0 39,000 D  
Restricted Stock Unit (RSU) (1) 03/05/2022   M     12,500   (5) 03/05/2025 Common Stock 12,500 $ 0 37,500 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MOLINA ARTURO MD
C/O SUTRO BIOPHARMA, INC.
111 OYSTER POINT BLVD.
SOUTH SAN FRANCISCO, CA 94080
      Chief Medical Officer  

Signatures

 /s/ Edward C. Albini as attorney-in-fact for Arturo Molina, M.D.   03/07/2022
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each RSU represents a contingent right to receive one (1) share of the issuer's Common Stock upon settlement.
(2) 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 the RSUs and does not represent a sale by the reporting person.
(3) The option vests as to 2.0833% of the total shares monthly, beginning on April 4, 2022, with 100% of the total shares vested and exercisable on March 4, 2026, subject to the reporting person's provision of service to the issuer on each vesting date.
(4) 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.
(5) The RSUs vest as to 1/4th of the total shares annually beginning on March 5, 2022, subject to continued service through each vesting date.

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