Merck & Co., Inc. — Director's Dealing 2018

Oct 2, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: SUTRO BIOPHARMA INC (STRO)
CIK: 0001382101
Period of Report: 2018-10-01

Reporting Person: Merck & Co., Inc. (10% Owner)
Reporting Person: Merck Sharp & Dohme Corp. (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-10-01	Common Stock	C	2056843	—	Acquired	2056843	Indirect
2018-10-01	Common Stock	P	666666	$15	Acquired	2723509	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2018-10-01	Series E Redeemable Convertible Preferred Stock	$	C	74794315	Disposed		Common Stock (2056843)	Indirect

Footnotes

F1: Each share of Series E redeemable convertible preferred stock (the "Series E Preferred") automatically converted into 0.0275 shares of the Issuer's common stock upon the closing of the Issuer's sale of its common stock in its firm commitment underwritten initial public offering pursuant to a registration statement on Form S-1 (File No. 333-227103) under the Securities Act of 1933, as amended. The Series E Preferred had no expiration date.

F2: These securities are owned directly by Merck Sharp & Dohme Corp., which is a direct, wholly owned subsidiary of Merck & Co., Inc. ("Merck"). Merck is an indirect beneficial owner of the reported securities.