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                                                                    Exhibit 4.10

                      REGISTRATION RIGHTS JOINDER AGREEMENT

          WHEREAS, The Jean Coutu Group (PJC) Inc. (the "Company"), certain
Guarantors and the Initial Purchasers heretofore executed and delivered a
Registration Rights Agreement ("Registration Rights Agreement") dated as of July
30, 2004, providing for the filing of a registration statement with the SEC
registering the Exchange Securities. All capitalized terms used herein but not
defined, shall have the meaning assigned thereto in the Registration Rights
Agreement;

          WHEREAS, as a condition to the consummation of the offering of the
Securities, certain of the Guarantors, none of which was originally party to the
Registration Rights Agreement, have agreed to join the Registration Rights
Agreement upon consummation of the acquisition by the Company of all of the
outstanding capital stock of Eckerd Corporation, a Delaware Corporation, Thrift
Drug, Inc., a Delaware corporation, and Genovese Drug Stores, Inc., a Delaware
corporation, on terms described below;

          WHEREAS, the undersigned and their board of directors (or equivalent
thereof) have concluded that the execution of this Joinder Agreement is in their
best interests and have received fair value for the execution of this Joinder
Agreement based on the benefits to be received by the undersigned as part of the
consolidated group of entities in which the Company is the parent entity;

          NOW, THEREFORE, in consideration of the benefits that each Guarantor
has or will receive under the Registration Rights Agreement, each Guarantor
signatory hereto hereby agrees for the benefit of the Initial Purchasers, as
follows:

     A.   Each of the undersigned hereby acknowledges that it has received and
          reviewed a copy of the Registration Rights Agreement and all other
          documents it deems fit to enter into this Agreement, and acknowledges
          and agrees to (i) join and become a party to the Registration Rights
          Agreement as indicated by its signature below; (ii) be bound by all
          covenants, agreements, representations, warranties and acknowledgments
          attributable to the Company and the Guarantors (including the
          Company's and the Guarantors' obligations as indemnifying parties) in
          the Registration Rights Agreement as if made by, and with respect to,
          each signatory hereto; and (iii) jointly and severally, perform all
          obligations and duties required of the Company and the Guarantors
          pursuant to the Registration Rights Agreement, in each case under (i),
          (ii) and (iii) as if an original party thereto.

     B.   Each of the undersigned hereby represents and warrants to and agrees
          with the Initial Purchasers that it has all the requisite corporate
          power and

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          authority and the legal right to execute, deliver and perform its
          obligations under this Joinder Agreement, that performance of this
          Joinder Agreement does not and will not violate any provisions of its
          charter, by-laws or other similar document, or, except as could not
          reasonably be expected to result in a material adverse effect, any
          contractual obligations binding on it; and that when this Joinder
          Agreement is executed and delivered, it will constitute a valid and
          legally binding agreement enforceable against each of the undersigned
          in accordance with its terms.

     C.   Each of the undersigned hereby irrevocably agrees that the obligations
          of such Guarantor under the Registration Rights Agreement shall be
          limited to the maximum amount which, after giving effect to all other
          contingent and fixed liabilities of such Guarantor and after giving
          effect to any collections from or payment made by or on behalf of any
          other Guarantor in respect of the obligations of such other Guarantor
          under the Registration Rights Agreement, will result in the
          obligations of such Guarantor under the Registration Rights Agreement
          not constituting a fraudulent conveyance for purposes of any federal,
          state, local or provincial bankruptcy, fraudulent conveyance or other
          laws.

          THIS JOINDER AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT GIVING EFFECT TO THE
CONFLICTS OF LAWS PRINCIPLES THEREOF.

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          IN WITNESS WHEREOF, the undersigned has executed this agreement this
31st day of July, 2004.


                                         ECKERD CORPORATION
                                         ECKERD FLEET, INC.
                                         EDC DRUG STORES, INC.
                                         EDC LICENSING, INC.
                                         GENOVESE DRUG STORES, INC.
                                         THRIFT DRUG, INC.
                                         THRIFT DRUG SERVICES, INC.


                                         By: /s/ Michel Coutu
                                            ------------------------------------

                                             Michel Coutu, as President of each