SC 13G 1 glaxooncomed-13g_0213.htm

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

OncoMed Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

68234X102

(CUSIP Number)

December 31, 2013

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

o Rule 13d-1(c)

x Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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.

13G

CUSIP No. 68234X102

1. Names of Reporting Persons.

GlaxoSmithKline plc

2. Check the Appropriate Box if a Member of a Group

(a) o

(b) o

3. SEC Use Only

4. Citizenship or Place of Organization

England and Wales

   Number of Shares
   Beneficially
   Owned by
   Each Reporting
   Person With:

5. Sole Voting Power

2,607,546

6. Shared Voting Power

7. Sole Dispositive Power

2,607,546

8. Shared Dispositive Power

9. Aggregate Amount Beneficially Owned by Each Reporting Person

2,607,546

10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares o

11. Percent of Class Represented by Amount in Row (9)

9.4%

12. Type of Reporting Person

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CUSIP No. 68234X102

ITEM 1.

(a)

Name of Issuer:

OncoMed Pharmaceuticals, Inc.

(b) Address of Issuer's Principal Executive Offices:

800 Chesapeake Drive

Redwood City, California 94063

ITEM 2.

(a)

Name of Person Filing:

GlaxoSmithKline plc.

(b)

Address of Principal Business Office, or if None, Residence:

980 Great West Road

Brentford

Middlesex

TW8 9GS

England

England and Wales

(d) Title of Class of Securities:

Common Stock, par value $0.001

(e) CUSIP Number:

68234X102

ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO SS.240.13d-1(b) OR 240.13d-2(b) OR (c), CHECK WHETHER THE PERSON FILING IS A:

Not Applicable

ITEM 4. OWNERSHIP.

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

The information in items 1 and 5 through 11 on the cover pages (page 2) on Schedule 13G is hereby incorporated by reference.

13G

CUSIP No. 68234X102

ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [ ].

INSTRUCTION: Dissolution of a group requires a response to this item.

ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than five percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.

GlaxoSmithKline LLC* 2,607,546 9.4%

*Shares held directly by GlaxoSmithKline LLC, an indirect wholly-owned subsidiary of Reporting Person.

ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.

If a parent holding company or Control person has filed this schedule, pursuant to Rule 13d-1(b)(1)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company or control person has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.

Not Applicable

ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.

If a group has filed this schedule pursuant to ss.240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to ss.240.13d-1(c) or ss.240.13d-1(d), attach an exhibit stating the identity of each member of the group.

Not Applicable

ITEM 9. NOTICE OF DISSOLUTION OF GROUP.

Notice of dissolution of a group may be furnished as an exhibit stating the date of the dissolution and that all further filings with respect to transactions in the security reported on will be filed, if required, by members of the group, in their individual capacity. See Item 5.

Not Applicable

13G

CUSIP No. 68234X102

ITEM 10. CERTIFICATIONS.

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having such purpose or effect.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

02/13/2014

________________________________

(Date)

/s/ Simon Dingemans

________________________________

(Signature)

Simon Dingemans, Chief Financial Officer

________________________________

(Name/Title)

The original statement shall be signed by each person on whose behalf the statement is filed or his authorized representative. If the statement is signed on behalf of a person by his authorized representative other than an executive officer or general partner of the filing person, evidence of the representative's authority to sign on behalf of such person shall be filed with the statement, provided, however, that a power of attorney for this purpose which is already on file with the Commission may be incorporated by reference. The name and any title of each person who signs the statement shall be typed or printed beneath his signature.