Exhibit 10.51

Form of RSU Grant Agreement

Grant No.

ENDO PHARMACEUTICALS HOLDINGS INC.

ENDOCENTIVE STOCK AWARD AGREEMENT

UNDER THE 2007 STOCK INCENTIVE PLAN

This Endocentive Stock Award Agreement (this Award Agreement), is made and entered into as of the date of grant set forth below (the Date of Grant) by and between Endo Pharmaceuticals Holdings Inc., a Delaware
corporation (the Company), and the participant named below (the Participant). Capitalized terms not defined herein shall have the meanings ascribed to them in the Endo Pharmaceuticals Holdings Inc. 2007 Stock Incentive Plan
(the Plan). Where the context permits, references to the Company shall include any successor to the Company.

Name of Participant:

Social Security No.:

Address:

Number of Endocentive Stock Awards:

Date of Grant:

Vesting Dates:

1. Grant of Endocentive Stock
Awards. The Company hereby grants to the Participant the total number Endocentive restricted stock units set forth above (the Endocentive Stock Awards), subject to all of the terms and conditions of this Award Agreement
and the Plan.

2. Form of Payment and Vesting. Each Endocentive Stock Award granted hereunder shall represent the right to receive
(1) one share of Company Stock as of the date of vesting. Except as provided in Section 7 of the Plan or Paragraph 4 of this Award Agreement, such vesting shall occur on the vesting dates set forth above, provided that the Participant is
employed by the Company on the applicable vesting date. Notwithstanding the above, a share of Company Stock shall be treated as delivered on the applicable vesting date provided that it is delivered on a date following the vesting date that is in
the same calendar year as the vesting date or, if later, by the fifteenth day of the third calendar month following the vesting date.



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3. Restrictions

(a) The Endocentive Stock Awards granted hereunder may not be sold, assigned, transferred, pledged, hypothecated or otherwise disposed of
or encumbered, and shall be subject to a risk of forfeiture and until any additional requirements or restrictions contained in this Award Agreement or in the Plan have been otherwise satisfied, terminated or expressly waived by the Company in
writing.

(b) Except as provided in Section 4, upon vesting of
the Endocentive Stock Awards, the shares subject to the Endocentive Stock Awards shall be issued hereunder (provided that such issuance is otherwise in accordance with federal and state securities laws) as soon as practicable thereafter, but in any
event no later than the end of the taxable year in which such vesting occurs or, if later, by the 15thday of the third calendar month following the
vesting date.

4. Termination of Employment Services; Disability

(a) Termination of Employment For Cause. Upon the Participants termination of employment with the Company and its
Subsidiaries for Cause all of the Participants unvested Endocentive Stock Awards shall be forfeited as of such date.

(b) Termination of Employment on Account of Death. Upon termination of the Participants employment on account of death, all of the Participants unvested Endocentive Stock Awards shall vest immediately.

(c) Termination of Employment on Account of Voluntary Retirement with Consent of Company. If a Participant voluntarily Retires with
the consent of the Company, all of the Participants unvested Endocentive Stock Awards as of date of termination shall continue to vest in accordance with the original vesting schedule set forth in Section 2 of this Award Agreement.

(d) Termination of Employment for any Other Reason. Unless otherwise provided in an individual agreement with the
Participant, if the Participant has a termination of employment for any reason other than the reasons enumerated in paragraphs (a) through (d) above, Endocentive Stock Awards that are unvested as of date of termination shall be forfeited.

(e) Disability. If the Participant incurs a Disability that also constitutes a disability within the
meaning of Section 409A, all of the Participants unvested Endocentive Stock Awards as of the date of such Disability shall continue to vest in accordance with the original four (4) year vesting schedule set forth in Section 2 of
this Award Agreement regardless of any subsequent termination of employment.

5. No Shareholder Rights Prior to Vesting. The
Participant shall have no rights of a shareholder (including the right to distributions or dividends) until shares of Company Stock are issued pursuant to the terms of this Award Agreement.



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6. Endocentive Stock Award (RSU) Agreement Subject to Plan. This Award Agreement is made pursuant
to all of the provisions of the Plan, which is incorporated herein by this reference, and is intended, and shall be interpreted in a manner, to comply therewith. In the event of any conflict between the provisions of this Award Agreement and the
provisions of the Plan, the provisions of the Plan shall govern.

7. No Rights to Continuation of Employment. Nothing in the Plan or
this Award Agreement shall confer upon the Participant any right to continue in the employ of the Company or any Subsidiary thereof or shall interfere with or restrict the right of the Company or its shareholders (or of a Subsidiary or its
shareholders, as the case may be) to terminate the Participants employment any time for any reason whatsoever, with or without cause.

8. Tax Withholding. The Company shall be entitled to require a cash payment by or on behalf of the Participant and/or to deduct from other Endocentive Stock Awards granted hereunder of compensation payable to the Participant any sums
required by federal, state or local tax law to be withheld or to satisfy any applicable payroll deductions with respect to the vesting of, lapse of restrictions on, or payment of any Endocentive Stock Award.

9. Section 409A Compliance. The intent of the parties is that payments and benefits under this Agreement comply with Section 409A of the
Code to the extent subject thereto, and, accordingly, to the maximum extent permitted, this Agreement shall be interpreted and be administered to be in compliance therewith. Notwithstanding anything contained herein to the contrary, to the extent
required in order to avoid accelerated taxation and/or tax penalties under Section 409A of the Code, the Participant shall not be considered to have terminated employment with the Company for purposes of this Agreement and no payment shall be
due to the Participant under this Agreement until the Participant would be considered to have incurred a separation from service from the Company within the meaning of Section 409A of the Code. Any payments described in this
Agreement or the Plan that are due within the short term deferral period as defined in Section 409A of the Code shall not be treated as deferred compensation unless applicable law requires otherwise. Notwithstanding anything to the
contrary in this Agreement or the Plan, to the extent that any Endocentive Stock Awards are payable upon a separation from service and such payment would result in the imposition of any individual excise tax and late interest charges imposed under
Section 409A of the Code, the settlement and payment of such awards shall instead be made on the first business day after the date that is six (6) months following such separation from service (or death, if earlier).

10. Governing Law. This Award Agreement shall be governed by, interpreted under, and construed and enforced in accordance with the internal laws,
and not the laws pertaining to conflicts or choices of laws, of the State of Delaware applicable to agreements made and to be performed wholly within the State of Delaware.



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11. Binding on Successors. The terms of this Award Agreement shall be binding upon the Participant
and upon the Participants heirs, executors, administrators, personal representatives, transferees, assignees and successors in interest, and upon the Company and its successors and assignees, subject to the terms of the Plan.

12. No Assignment. Notwithstanding anything to the contrary in this Award Agreement, neither this Award Agreement nor any rights granted herein
shall be assignable by the Participant.

13. Necessary Acts. The Participant hereby agrees to perform all acts, and to execute and
deliver any documents that may be reasonably necessary to carry out the provisions of this Award Agreement, including but not limited to all acts and documents related to compliance with federal and/or state securities and/or tax laws.

14. Entire Endocentive Stock Award (RSU) Agreement. This Award Agreement and the Plan contain the entire agreement and understanding among the
parties as to the subject matter hereof.

15. Headings. Headings are used solely for the convenience of the parties and shall not be
deemed to be a limitation upon or descriptive of the contents of any such Section.

16. Counterparts. This Award Agreement may be
executed in any number of counterparts, each of which shall be deemed to be an original and all of which together shall be deemed to be one and the same instrument.

17. Notices. All notices and other communications under this Agreement shall be in writing and shall be given by first class mail, certified or registered with return receipt requested, and shall be deemed to
have been duly given three days after mailing to the respective parties named below:



|                       |  |                                                                                                 
|---------------------- |  | ------------------------------------------------------------------------------------------------
|If to Company:         |  | Endo Pharmaceuticals Holdings Inc. 100 Endo Boulevard Chadds Ford, PA 19317 Attention:
Treasurer
|                       | 
|If to the Participant: |  | At the address noted above.                                                                     

Either party hereto may change such partys address for notices by notice duly given pursuant
hereto.

18. Amendment. No amendment or modification hereof shall be valid unless it shall be in writing and signed by all parties
hereto.

19. Acceptance. The Participant hereby acknowledges receipt of a copy of the Plan and this Award Agreement. The Participant
has read and understand the terms and provision thereof, and accepts the Endocentive Stock Awards subject to all the terms and conditions of the Plan and this Award Agreement.



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IN WITNESS WHEREOF, the parties hereto have executed this Award Agreement as of the date set forth above.



|                                                                  |  | 
|----------------------------------------------------------------- |  | 
|ENDO PHARMACEUTICALS HOLDINGS INC.                               
|                                                                  | 
|By                                                                |  | 
|Name: David P. Holveck Title:
President & Chief Executive Officer



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|PARTICIPANT
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|Signature   |  | 
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