Form: 3

Initial statement of beneficial ownership of securities

September 26, 2018

FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF 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 *
  SVLSF V, LLC
2. Date of Event Requiring Statement (Month/Day/Year)
09/26/2018
3. Issuer Name and Ticker or Trading Symbol
SUTRO BIOPHARMA INC [STRO]
(Last)
(First)
(Middle)
ONE BOSTON PLACE, 201 WASHINGTON ST., STE 3900
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

BOSTON, MA 02108
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Series A Preferred Stock   (1)   (1) Common Stock 21,776 $ (1) I By International Life Sciences Fund III Co-Investment, L.P. (2)
Series B Preferred Stock   (3)   (3) Common Stock 131,683 $ (3) I By International Life Sciences Fund III Co-Investment, L.P. (2)
Series C Preferred Stock   (4)   (4) Common Stock 58,632 $ (4) I By International Life Sciences Fund III Co-Investment, L.P. (2)
Series C Preferred Stock Warrant (right to buy)   (5)   (5) Series C Preferred Stock 11,544 $ 0.4797 (6) I By International Life Sciences Fund III Co-Investment, L.P. (2)
Series A Preferred Stock   (1)   (1) Common Stock 1,835,270 $ (1) I By International Life Sciences Fund III (LP1), L.P. (2)
Series B Preferred Stock   (3)   (3) Common Stock 11,097,596 $ (3) I By International Life Sciences Fund III (LP1), L.P. (2)
Series C Preferred Stock   (4)   (4) Common Stock 4,941,391 $ (4) I By International Life Sciences Fund III (LP1), L.P. (2)
Series C Preferred Stock Warrant (right to buy)   (5)   (5) Series C Preferred Stock 973,028 $ 0.4797 (6) I By International Life Sciences Fund III (LP1), L.P. (2)
Series A Preferred Stock   (1)   (1) Common Stock 17,533 $ (1) I By International Life Sciences Fund III Strategic Partners, L.P. (2)
Series B Preferred Stock   (3)   (3) Common Stock 106,019 $ (3) I By International Life Sciences Fund III Strategic Partners, L.P. (2)
Series C Preferred Stock   (4)   (4) Common Stock 47,205 $ (4) I By International Life Sciences Fund III Strategic Partners, L.P. (2)
Series C Preferred Stock Warrant (right to buy)   (5)   (5) Series C Preferred Stock 9,293 $ 0.4797 (6) I By International Life Sciences Fund III Strategic Partners, L.P. (2)
Series C Preferred Stock   (4)   (4) Common Stock 9,217,015 $ (4) I By SV Life Sciences Fund V, L.P. (7)
Series D Preferred Stock   (8)   (8) Common Stock 6,683,697 $ (8) I By SV Life Sciences Fund V, L.P. (7)
Series E Preferred Stock   (9)   (9) Common Stock 9,155,794 $ (9) I By SV Life Sciences Fund V, L.P. (7)
Series C Preferred Stock   (4)   (4) Common Stock 194,786 $ (4) I By SV Life Sciences Fund V Strategic Partners, L.P. (10)
Series D Preferred Stock   (8)   (8) Common Stock 141,249 $ (8) I By SV Life Sciences Fund V Strategic Partners, L.P. (10)
Series E Preferred Stock   (9)   (9) Common Stock 193,492 $ (9) I By SV Life Sciences Fund V Strategic Partners, L.P. (10)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
SVLSF V, LLC
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
ILSF III, LLC
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
INTERNATIONAL LIFE SCIENCES FUND III (GP), L.P.
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
INTERNATIONAL LIFE SCIENCES FUND III CO-INVESTMENT, L.P.
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
INTERNATIONAL LIFE SCIENCES FUND III (LP1), L.P.
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
INTERNATIONAL LIFE SCIENCES FUND III STRATEGIC PARTNERS, L.P.
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
SV Life Sciences Fund V (GP), LP
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
SV LIFE SCIENCES FUND V LP
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    
SV Life Sciences Fund V Strategic Partners, L.P.
ONE BOSTON PLACE
201 WASHINGTON ST., STE 3900
BOSTON, MA 02108
    X    

Signatures

/s/ Brent Faduski as authorized officer of SVLSF V, LLC 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of ILSF III, LLC 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of ILSF III, LLC, the GP of International Life Sciences Fund III (GP), L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of ILSF III, LLC, the GP of International Life Sciences Fund III (GP), L.P., the GP of International Life Sciences Fund III Co-Investment, L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of ILSF III, LLC, the GP of International Life Sciences Fund III (GP), L.P., the GP of International Life Sciences Fund III (LP1), L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of ILSF III, LLC, the GP of International Life Sciences Fund III (GP), L.P., the GP of International Life Sciences Fund III Strategic Partners, L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of SVLSF V, LLC, the GP of SV Life Sciences Fund V (GP), L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of SVLSF V, LLC, the GP of SV Life Sciences Fund V (GP), L.P., the GP of SV Life Sciences Fund V, L.P. 09/26/2018
**Signature of Reporting Person Date

/s/ Brent Faduski as authorized officer of SVLSF V, LLC, the GP of SV Life Sciences Fund V (GP), L.P, the GP of SV Life Sciences Fund V Strategic Partners, L.P. 09/26/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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 share of the issuer's Series A Preferred Stock will automatically convert into 0.0433 share of the issuer's Common Stock immediately upon the closing of the issuer's initial public offering ("IPO") and has no expiration date.
(2) International Life Sciences Fund III (GP), LP. ("Fund III GP") is the general partner of each of: (i) International Life Sciences Fund III (LP1), L.P. ("ILSF LP1"), (ii) International Life Sciences Fund III Co-Investment, L.P. ("ILSF Co-Invest") and (iii) International Life Sciences Fund III Strategic Partners, L.P. ("ILSF Strategic" and collectively, the "Fund III Entities"). ILSF III, LLC (the "ILSF General Partner") is the general partner of Fund III GP and, through an investment committee comprised of James Garvey, Kate Bingham, Eugene D. Hill, III and Michael J. Ross controls voting and investment decisions over the Issuer's shares held by the Fund III Entities by majority vote. Each of Fund III GP, ILSF General Partner, and each member of the investment committee of ILSF General Partner disclaims beneficial ownership over the Shares held by the Fund III Entities except to the extent of any pecuniary interest therein.
(3) Each share of the issuer's Series B Preferred Stock will automatically convert into 0.0578 share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date.
(4) Each share of the issuer's Series C Preferred Stock will automatically convert into 0.0370 share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date.
(5) The warrant is exercisable at any time at the holder's election on a one-for one basis and automatically terminates on the completion of the issuer's initial public offering if not earlier exercised.
(6) The warrant has a net exercise provision under which the holder, in lieu of paying the exercise price in cash, can surrender the warrant and receive a net number of shares of preferred stock based on the fair market value of such stock at the time of exercise, after deducting the aggregate exercise price.
(7) These shares are owned directly by SV Life Sciences Fund V, L.P. ("SVLS V LP"). SV Life Sciences Fund V (GP), LP ("SVLS V GP") is the general partner of SVLS V LP. The general partner of SVLS V GP is SVLSF V, LLC. Kate Bingham, James Garvey, Eugene D. Hill, III and Michael J. Ross are members of the investment committee of SVLSF V, LLC. SVLS V GP, SVLSF V, LLC and each of the individuals comprising the SVLSF V, LLC investment committee may be deemed to share voting, dispositive and investment power over the shares held of record by SVLS V LP. Each of SVLS V GP, SVLSF V, LLC and the individual members of the SVLSF V, LLC investment committee disclaims beneficial ownership of these securities and this report shall not be deemed to be an admission that any one of them is the beneficial owner of such securities for purposes of Section 16 or any other purpose, except to the extent of their pecuniary interest therein.
(8) Each share of the issuer's Series D Preferred Stock will automatically convert into 0.0405 share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date.
(9) Each share of the issuer's Series E Preferred Stock will automatically convert into 0.0275 share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date.
(10) These shares are owned directly by SV Life Sciences Fund V Strategic Partners, L.P. ("SVLS V SPP"). SVLS V GP is the general partner of SVLS V SPP. The general partner of SVLS V GP is SVLSF V, LLC. Kate Bingham, James Garvey, Eugene D. Hill, III and Michael J. Ross are members of the investment committee of SVLSF V, LLC. SVLS V GP, SVLSF V, LLC and each of the individuals comprising the SVLSF V, LLC investment committee may be deemed to share voting, dispositive and investment power over the shares held of record by SVLS V SPP. Each of SVLS V GP, SVLSF V, LLC and the individual members of the SVLSF V, LLC investment committee disclaims beneficial ownership of these securities and this report shall not be deemed to be an admission that any one of them is the beneficial owner of such securities for purposes of Section 16 or any other purpose, except to the extent of their pecuniary interest therein.

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