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                                                                    Exhibit 10.3


                                    AMENDMENT

                                       TO

                          SHELF REGISTRATION AGREEMENT

         AMENDMENT TO SHELF REGISTRATION AGREEMENT, dated as of June 10, 2004
(the "Amendment"), by and between Endo Pharmaceuticals Holdings Inc., a Delaware
corporation (the "Company") and Endo Pharma LLC, a Delaware limited liability
company (the "LLC"). The Company and the LLC are collectively referred to herein
as the "Parties."

         WHEREAS, the Parties have entered into that certain Shelf Registration
Agreement, dated as of April 30, 2004 (the "Shelf Agreement");

         WHEREAS, on April 30, 2004, the Company filed a Registration Statement
on Form S-3 with the Securities and Exchange Commission to register 30 million
shares of the Company's common stock, par value $.01 (the "Common Stock") for
resale by the LLC and other stockholders of the Company (the "Shelf Registration
Statement");

         WHEREAS, the Shelf Registration Statement provides that the Selling
Stockholders (as defined below) will only sell the Common Stock being offered
thereby to underwriters for resale to the public or institutional investors;

         WHEREAS, the Company will file an amendment to the Shelf Registration
Statement (the "Shelf Registration Amendment") to include block sales,
derivative transactions with third parties and other types of hedging
transactions as potential methods by which the Selling Stockholders may sell the
Common Stock being offered thereby; and

         WHEREAS, the Parties desire to enter into this Amendment in order to
make necessary changes to the Shelf Agreement to reflect certain changes made to
the Shelf Registration Statement in the Shelf Registration Amendment.

         NOW, THEREFORE, in consideration of the mutual promises and obligations
of the Parties set forth in this Amendment, the Parties hereto agree to amend
the Shelf Agreement as follows:

         1. Section 1.1 of the Shelf Agreement is hereby deleted in its entirety
and the following new Section 1.1 will be added:

         "Section 1.1 Shelf Registration Agreement. The Company agrees to file
with the Commission a Shelf Registration Statement to register 30 million shares
of the Company's Common Stock, which will include up to 29,674,000 shares of
Common Stock for resale by the LLC (including shares to be sold on behalf of its
members) and 326,000 shares of Common Stock for resale by other stockholders of
the Company, as determined by the Company and the LLC (collectively, the
"Selling Stockholders"), to be sold, from time to time, in one or more of the
following types of transactions: (i) underwritten offerings; (ii) block
transactions; (iii) derivative transactions with third parties; or (iv) other
types of hedging transactions (each a "Take-down Transaction"). The Company has
no obligation to ensure that the Shelf Registration Statement is declared
effective by the Commission."


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         2. Section 1.3 of the Shelf Agreement is hereby deleted in its entirety
and the following new Section 1.3 will be added:

         "Section 1.3 Procedures for Shelf Registration. The Company and the LLC
agree that the procedures for any Take-down Transaction will be in conformity
with those set forth in the Registration Rights Agreement, the Employee
Stockholders Agreement and the Stockholders Agreement and shall apply to any
sales of Common Stock sold in a Take-down Transaction and that the provisions
set forth in Section 3(h), the paragraph immediately following Section 3(o) and
the last paragraph of Section 3 of the Registration Rights Agreement shall apply
to the Shelf Registration Statement."





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         IN WITNESS WHEREOF, the parties hereto have duly executed this
Amendment as of the date first written above.



                                     ENDO PHARMA LLC


                                     By:  /s/ Michael B. Goldberg
                                         ----------------------------------
                                         Name: Michael B. Goldberg
                                         Title: Manager


                                     ENDO PHARMACEUTICALS HOLDINGS, INC.


                                     By:  /s/ Jeffrey R. Black
                                         ----------------------------------
                                         Name: Jeffrey R. Black
                                         Title: Executive Vice President,
                                                Chief Financial Officer and
                                                Treasurer






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