SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Skyline Venture Partners V LP (Last) (First) (Middle) 525 UNIVERSITY AVENUE (Street) PALO ALTO CA 94301 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol SUTRO BIOPHARMA INC [ STRO ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 10/01/2018
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

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	10/01/2018		C		925,578	A	(1)	925,578	I	By Skyline Venture Partners V, L.P.(2)
Common Stock	10/01/2018		C		520,264	A	(3)	1,445,842	I	By Skyline Venture Partners V, L.P.(2)
Common Stock	10/01/2018		C		514,211	A	(4)	1,960,053	I	By Skyline Venture Partners V, L.P.(2)

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 Securities Underlying Derivative Security (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: 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
Series C Preferred Stock	(1)	10/01/2018		C			25,015,635	(1)	(1)	Common Stock	925,578	$0	0	I	By Skyline Venture Partners V, L.P.(2)
Series D Preferred Stock	(3)	10/01/2018		C			12,846,023	(3)	(3)	Common Stock	520,264	$0	0	I	By Skyline Venture Partners V, L.P.(2)
Series E Preferred Stock	(4)	10/01/2018		C			18,698,578	(4)	(4)	Common Stock	514,211	$0	0	I	By Skyline Venture Partners V, L.P.(2)

1. Name and Address of Reporting Person* Skyline Venture Partners V LP (Last) (First) (Middle) 525 UNIVERSITY AVENUE (Street) PALO ALTO CA 94301 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Skyline Venture Management V, LLC (Last) (First) (Middle) 525 UNIVERSITY AVENUE (Street) PALO ALTO CA 94301 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* KANEKO YASUNORI (Last) (First) (Middle) 525 UNIVERSITY AVENUE (Street) PALO ALTO CA 94301 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Each share of the issuer's Series C Preferred Stock automatically converted into 0.0370 share of the issuer's Common Stock on October 1, 2018 in connection with the closing of the issuer's sale of its Common Stock in its firm commitment initial public offering (the "IPO") pursuant to a registration statement on Form S-1 (File No. 333-227103) under the Securities Act of 1933, as amended (the "Registration Statement"), and had no expiration date.

2. These securities are held of record by Skyline Venture Partners V, L.P. ("Skyline L.P."). Skyline Venture Management V, LLC ("Skyline Management") is the general partner of Skyline L.P. John G. Freund and Yasunori Kaneko, are the managing directors of Skyline Management, and each may be deemed to share voting and investment power over the securities held by Skyline L.P. and disclaims beneficial ownership over such securities except to the extent of their pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purposes. Mr. Freund is a director of the Issuer and, accordingly, files separate Section 16 reports.

3. Each share of the issuer's Series D Preferred Stock automatically converted into 0.0405 share of the issuer's Common Stock on October 1, 2018 in connection with the closing of the issuer's sale of its Common Stock in its IPO pursuant to the Registration Statement, and had no expiration date.

4. Each share of the issuer's Series E Preferred Stock automatically converted into 0.0275 share of the issuer's Common Stock on October 1, 2018 in connection with the closing of the issuer's sale of its Common Stock in its IPO pursuant to the Registration Statement, and had no expiration date.

	Skyline Venture Partners V, L.P. By: Skyline Venture Management V, LLC Its: General Partner /s/ Kerensa Kenny, Attorney-in-Fact	10/03/2018
	Skyline Venture Management V, LLC /s/ Kerensa Kenny, Attorney-in-Fact	10/03/2018
	Yasunori Kaneko /s/ Kerensa Kenny, Attorney-in-Fact	10/03/2018
	** Signature of Reporting Person	Date
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