Ownership Submission
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, Section 17(a) of the Public Utility Holding Company Act of 1935 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 *
ROOT JONATHAN D
  2. Issuer Name and Ticker or Trading Symbol
OncoMed Pharmaceuticals Inc [OMED]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
2735 SAND HILL ROAD
3. Date of Earliest Transaction (Month/Day/Year)
07/23/2013
(Street)

MENLO PARK, CA 94025
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 07/23/2013   C   1,028,381 A (1) 1,028,381 I Directly owned by USVP VIII (2)
Common Stock 07/23/2013   C   1,215,407 A (1) 2,243,788 I Directly owned by USVP VIII (2)
Common Stock 07/23/2013   C   1,505,032 A (1) 3,748,820 I Directly owned by USVP VIII (2)
Common Stock 07/23/2013   P   155,164 A $ 17 3,903,984 I Directly owned by USVP VIII (2)
Common Stock 07/23/2013   C   9,505 A (1) 9,505 I Directly owned by EP VIII-A (2)
Common Stock 07/23/2013   C   11,233 A (1) 20,738 I Directly owned by EP VIII-A (2)
Common Stock 07/23/2013   C   13,910 A (1) 34,648 I Directly owned by EP VIII-A (2)
Common Stock 07/23/2013   P   1,434 A $ 17 36,082 I Directly owned by EP VIII-A (2)
Common Stock 07/23/2013   C   4,817 A (1) 4,817 I Directly owned by EP VIII-B (2)
Common Stock 07/23/2013   C   5,694 A (1) 10,511 I Directly owned by EP VIII-B (2)
Common Stock 07/23/2013   C   7,051 A (1) 17,562 I Directly owned by EP VIII-B (2)
Common Stock 07/23/2013   P   727 A $ 17 18,289 I Directly owned by EP VIII-B (2)
Common Stock 07/23/2013   C   9,926 A (1) 9,926 I Directly owned by AFF VIII (2)
Common Stock 07/23/2013   C   11,731 A (1) 21,657 I Directly owned by AFF VIII (2)
Common Stock 07/23/2013   C   14,527 A (1) 36,184 I Directly owned by AFF VIII (2)
Common Stock 07/23/2013   P   1,498 A $ 17 37,682 I Directly owned by AFF VIII (2)

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
Series A Preferred Stock (1) (1) 07/23/2013   C     1,028,381   (3)   (4) Common Stock 1,028,381 (1) 0 I Directly owned by USVP VIII (2)
Series A Preferred Stock (1) (1) 07/23/2013   C     9,505   (3)   (4) Common Stock 9,505 (1) 0 I Directly owned by EP VIII-A (2)
Series A Preferred Stock (1) (1) 07/23/2013   C     4,817   (3)   (4) Common Stock 4,817 (1) 0 I Directly owned by EP VIII-B (2)
Series A Preferred Stock (1) (1) 07/23/2013   C     9,926   (3)   (4) Common Stock 9,926 (1) 0 I Directly owned by AFF VIII (2)
Series B Preferred Stock (1) (1) 07/23/2013   C     1,215,407   (3)   (4) Common Stock 1,215,407 (1) 0 I Directly owned by USVP VIII (2)
Series B Preferred Stock (1) (1) 07/23/2013   C     11,233   (3)   (4) Common Stock 11,233 (1) 0 I Directly owned by EP VIII-A (2)
Series B Preferred Stock (1) (1) 07/23/2013   C     5,694   (3)   (4) Common Stock 5,694 (1) 0 I Directly owned by EP VIII-B (2)
Series B Preferred Stock (1) (1) 07/23/2013   C     11,731   (3)   (4) Common Stock 11,731 (1) 0 I Directly owned by AFF VIII (2)
Series B-1 Preferred Stock (1) (1) 07/23/2013   C     1,505,032   (3)   (4) Common Stock 1,505,032 (1) 0 I Directly owned by USVP VIII (2)
Series B-1 Preferred Stock (1) (1) 07/23/2013   C     13,910   (3)   (4) Common Stock 13,910 (1) 0 I Directly owned by EP VIII-A (2)
Series B-1 Preferred Stock (1) (1) 07/23/2013   C     7,051   (3)   (4) Common Stock 7,051 (1) 0 I Directly owned by EP VIII-B (2)
Series B-1 Preferred Stock (1) (1) 07/23/2013   C     14,527   (3)   (4) Common Stock 14,527 (1) 0 I Directly owned by AFF VIII (2)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
ROOT JONATHAN D
2735 SAND HILL ROAD
MENLO PARK, CA 94025
  X   X    

Signatures

 /s/ Yvonne Li, Attorney-in-Fact for Jonathan D. Root   07/23/2013
**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 share of Series A, Series B and Series B-1 Preferred Stock automatically converted on a one-to-one basis into Common Stock immediately prior to the consummation of the Issuer's initial public offering on July 23, 2013.
(2) The reported securities are owned directly by each of U.S. Venture Partners VIII, L.P. ("USVP VIII"), USVP VIII Affiliates Fund, L.P. ("AFF VIII"), USVP Entrepreneur Partners VIII-A, L.P. ("EP VIII-A") and USVP Entrepreneur Partners VIII-B, L.P. ("EP VIII-B" and together with USVP VIII, AFF VIII and EP VIII-A, the "USVP Funds"). Presidio Management Group VIII, LLC, or PMG VIII, is the general partner of the USVP Funds, and may be deemed to have sole voting and dispositive power over the shares held by the USVP Funds. PMG VIII and Irwin Federman, Winston Fu, Steven Krausz, David Liddle, Jonathan Root, Christopher Rust, Casey Tansey and Philip Young, the managing members of PMG VII, who may be deemed to share voting and dispositive power over the reported securities, disclaim beneficial ownership of the reported securities held by the USVP Funds except to the extent of any pecuniary interest therein.
(3) The securities are immediately convertible.
(4) The expiration date is not relevant to the conversion of these securities.

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