Execution
      Copy

    


    MEMBERSHIP
      INTEREST PURCHASE AGREEMENT

    


    


    This
      MEMBERSHIP
      INTEREST PURCHASE AGREEMENT, dated
      November 1, 2007 (this “Agreement”),
      is
      made by and among MDC
      Acquisition Inc.,
      a
      Delaware corporation (“MDC
      Sub”);
      CPB
      Acquisition Inc.,
      a
      Delaware Corporation (“Acquisition
      Co.”);
      MDC
      Partners Inc.,
      a
      Canadian corporation (“MDC
      Partners”);
      Crispin
      & Porter Advertising, Inc.
      (d/b/a
      Crispin Porter & Bogusky), a Florida corporation (“CPB
      Inc.”);
      Charles
      Porter (“Porter”),
      Alex Bogusky (“Bogusky”),
      Jeff Hicks (“Hicks”),
      and
Jeff
      Steinhour (“Steinhour”;
      together with Porter, Bogusky and Hicks collectively referred to as the
“Employee
      Members”
and
      individually as an “Employee Member”);
      MDC
      Sub,
      together with the Acquisition Co., Employee Members and CPB Inc., collectively
      referred to as the “Members”
and
      individually a “Member”); and
      CRISPIN
      PORTER & BOGUSKY LLC, a
      Delaware limited liability company (the “Company”).
      Capitalized terms used herein and not otherwise defined shall have the meanings
      ascribed to such terms in the Company’s Amended and Restated Limited Liability
      Company Agreement dated as of January 8, 2001 (as subsequently amended, the
      “LLC
      Agreement”).

    


    


    WITNESSETH
      :

    


    WHEREAS,
      CPB
      Inc., the Employee Members and Acquisition Co. are parties to that certain
      LLC
      Agreement of the Company, which sets forth, among other things, the terms and
      conditions relating to transfer and ownership of the Membership Interests upon
      exercise of a put or call option; 

    


    WHEREAS,
      pursuant
      to the LLC Agreement, Acquisition Co. has the right to exercise (i) the “First
      Call” option with respect to the purchase of an additional 11% of Membership
      Interests from CPB Inc., and (ii) the “Second Call” option with respect to the
      purchase of an additional 17% of Membership Interests from CPB Inc., and has
      assigned such rights to exercise the First Call and the Second Call to MDC
      Sub;

    


    WHEREAS,
      the
      Employee Members and CPB Inc. (collectively, the “Sellers”)
      now
      desire to sell, and MDC Sub desires to purchase, an aggregate amount equal
      to
      28% of the issued and outstanding Membership Interests in the Company (the
      “Purchased
      Interests”),
      from
      the Sellers in the following applicable percentage amounts: CPB
      Inc. - 27%; Porter - 0.36%; Bogusky - 0.27%; Hicks - 0.27%; Steinhour -
      0.10%);

    


    WHEREAS,
      immediately following the execution and delivery of this Agreement, the parties
      hereto are entering into a further amendment to the LLC Agreement to reflect
      the
      transactions contemplated by this Agreement, including the transfer of the
      Purchased Interests to MDC Sub and the reallocation of Membership Interests
      such
      that following the Closing of the transactions contemplated by this Agreement,
      the Membership Interests in the Company will be owned as follows: MDC
      Sub - 28%; Acquisition Co. - 49% ; CPB Inc. - 23%.;  


    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

    NOW,
      THEREFORE,
      in
      consideration of the mutual covenants and agreements set forth in this
      Agreement, and for other good and valuable consideration, the receipt and
      sufficiency of which are hereby acknowledged, the parties do hereby agree as
      follows:

    


    1.            
      Purchase
      and Sale; Closing.
      

    


    (a) Sellers
      hereby sell, assign, transfer and deliver to MDC Sub, and MDC Sub hereby
      purchases from Sellers, the Purchased Interests.
      The
      Purchased Interests carry with it the right to share in the Profits and Losses
      of the Company (as such terms are defined in LLC Agreement) and the other
      economic attributes thereof (including distributions of Cash Flow) accruing
      from
      and after November 1, 2007 in respect of the Purchased Interests transferred
      hereby, and an initial Capital Account in the hands of MDC Sub equal to the
      product of (A) the CAP with respect to this purchase and (B) Seller's total
      Capital Account balance (all as such terms are defined the LLC Agreement) as
      of
      November 1, 2007.

    


    (b) The
      closing of the transaction contemplated by this Agreement (the “Closing”)
      is
      taking place simultaneously with the execution and delivery of this Agreement
      (the “Closing
      Date”),
      at
      the offices of MDC Partners Inc., 950 Third Avenue, New York, New York 10022
      or
      by the exchange of documents and instruments by mail, courier, telecopy and
      wire
      transfer to the extent mutually acceptable to the parties hereto. 

    


    (c) Effective
      as of November 1, 2007, MDC Sub, Acquisition Co. and CPB Inc. shall cause the
      Company to close its books for income tax purposes, and there will be no
      allocation of gains or losses to Sellers with respect to the Purchased Interests
      following the Closing Date. All distributions of Profits payable as of October
      31, 2007 in respect of the Membership Interests (including the Purchased
      Interests) shall be distributed and paid by the Company in the ordinary course
      following the Closing. In accordance with the LLC Agreement, the parties have
      agreed to elect to adopt the closing of the books method under Section 706
      of
      the Code for allocating CPB Inc.’s varying interests in the Company during the
      taxable year that includes the Closing Date.

     

    2.            
      Purchase
      Price.  

    


    (a) 
      In full
      consideration for the purchase by MDC Sub of the Purchased Interests, and in
      full satisfaction of any and all amounts due and owing by Acquisition Co. with
      respect to the Period One Formula Amount and the Period Two Formula Amount
      (as
      such terms are defined in the LLC Agreement), MDC Sub agrees to pay to Sellers
      an amount equal to the “Put/Call
      Purchase Price”,
      calculated and determined as follows:

    


    
      	 	
              (i)

            	
              At
                the Closing, a “Closing
                Payment”
                in an aggregate amount equal to $27,701,072, of which Closing Payment
                (x)
                an amount equal to $22,560,858 shall be paid in cash or immediately
                available funds (the “Cash
                Payment”)
                as allocated in accordance with Section 2(a)(ii) below, and (y) an
                amount
                equal to $5,140,214 shall be paid in the form of 514,025 shares of
                MDC
                Stock (the “Stock
                Payment”),
                as allocated in accordance with Section 2(a)(iii) below. “MDC Stock” shall
                mean MDC Partners’ Class A subordinate voting
                shares.

            


    


    
      
        
        

      

      
        2

        
          

        

      

      
        
        

      

    


    
      	 	
              (ii)

            	
              At
                Closing, the Cash Payment shall be paid and allocated among the Sellers
                in
                the following amounts: $21,755,114 paid to CPB Inc.; $290,068 paid
                to
                Porter; $217,551 paid to Bogusky; $217,551 paid to Hicks; and $80,574
                paid
                to Steinhour.

            


    

    


    
      	 	
              (iii)

            	
              Shares
                of MDC Stock representing the Stock Payment shall be issued and allocated
                among the Sellers in the following amounts: 495,662 shares of MDC
                Stock to
                CPB Inc.; 6,610 shares of MDC Stock to Porter; 4,958 shares of MDC
                Stock
                to Bogusky; 4,958 shares of MDC Stock to Hicks; and 1,837 shares
                of MDC
                Stock to Steinhour.

            


    

    


    


    
      	 	
              (iv)

            	
              The
                certificate representing the shares of MDC Stock to be issued as
                part of
                the Closing Payment shall be dated the date hereof and shall be delivered
                to the Sellers not later than ten (10) business days after the Closing
                Date. There shall be no contractual holding period for the shares
                of MDC
                Stock issued as part of the Stock
                Payment.

            


    

    


    (b) 
      The
      parties hereto acknowledge and agree that the Put/Call Purchase Price to be
      paid
      by MDC Sub pursuant to the terms and conditions set forth in this Agreement,
      together with any amounts paid in respect of the Capital Account Amount, will
      satisfy in
      full
      all
      payment obligations of MDC Sub, Acquisition Co., the Company and/or MDC
      Partners Inc. (“MDC
      Partners”)
      in
      connection with the Purchased Interests, the First Call, the First Put, the
      Second Call, and the Second Put, including without limitation satisfaction
      in
      full of any amount due in respect of the Capital Account Amount relating to
      the
      Purchased Interests, all as set forth in the LLC Agreement.  In
      addition, in the event that there exists any conflict regarding the
      language contained in this Agreement and the language contained in the LLC
      Agreement, the language contained in this Agreement shall govern.

    


    3.            
      Representations
      and Warranties by CPB Inc.
      Sellers
      hereby represent and warrant to MDC Sub as follows:

    


    (a) CPB
      Inc.
      is a corporation duly organized, validly existing and in good standing under
      the
      laws of the State of Florida, with full corporate power and authority to own
      its
      property and to carry on its business all as and in the places where such
      properties are now owned or operated or such business is now being
      conducted.

     

    
      
        
        

      

      
        3

        
          

        

      

      
        
        

      

    

    (b)
       Each
      of
      the Sellers has the full authority to make, execute, deliver and perform this
      Agreement and the transactions contemplated hereby. The execution and delivery
      of this Agreement by CPB Inc. and the consummation by CPB Inc. of the
      transactions contemplated hereby have been duly authorized by all required
      corporate action on behalf of CPB Inc. and its shareholders. This Agreement
      has
      been duly and validly executed and delivered by each of the Sellers and,
      assuming due authorization, execution and delivery by MDC Sub, constitutes
      a
      legal, valid and binding obligation of each of the Sellers, enforceable against
      each of Sellers in accordance with its terms.

    


    (c)
       Each
      of
      the Sellers is the owner of the applicable amount of the Purchased Interests
      being sold and transferred pursuant to this Agreement, free and clear of all
      mortgages, liens, security interests, encumbrances, claims, charges and
      restrictions of any kind or character (“Liens”)
      other
      than the LLC Agreement. No person or entity has or will have any claim against
      the Company, MDC Sub or any of their affiliates related to any share or future
      distribution from the Company or to the proceeds from the sale of the Purchased
      Interests.

    


    (d) Each
      of
      the Sellers hereby represent and warrant that none of the Sellers has agreed
      or
      made any written or verbal commitment to give any employee of the Company any
      bonus, gift, award or any similar type of remuneration, except as reflected
      in
      employment agreements or plans previously disclosed in writing to MDC or MDC
      Sub. Each of the Sellers agree that, from and after the date hereof, no portion
      or proceeds of the Put/Call Purchase Price shall be used to compensate or give
      any employee of the Company a bonus, gift, award or similar type of
      remuneration.

    


    (e) The
      Employee Members’ obligation to indemnify pursuant to Section 6 below based
      upon breaches of representations and warranties set forth in this Section 3
      shall be limited to the amount received by each such Employee Member for their
      respective Membership Interests purchased hereby.

     

    4.            
      Representations
      and Warranties by MDC Sub.
      MDC Sub
      and MDC Partners, as the case may be, hereby represent and warrant to Sellers
      as
      follows:

    


    (a) MDC
      Sub
      is a corporation duly organized, validly existing and in good standing under
      the
      laws of Delaware with full corporate power and authority to own its property
      and
      to carry on its business all as and in the places where such properties are
      now
      owned or operated or such business is now being conducted. MDC Sub is an
      indirect, wholly-owned subsidiary of MDC Partners. MDC Partners
      shall cause sufficient capital and/or MDC Stock, as the case may be, to be
      available to MDC Sub to meet its obligations to pay the Put/Call Purchase Price
      under Section 2 of this Agreement. If
      MDC
      Sub fails to meet its payment obligations under Section 2 hereof, then MDC
      Partners shall satisfy such payment obligations to the extent that MDC Sub
      failed to do so.

    


    (b) MDC
      Sub
      has the full corporate power and authority to make, execute, deliver and perform
      this Agreement and the transactions contemplated hereby. The execution and
      delivery of this Agreement by MDC Sub and the consummation of the transactions
      contemplated hereby have been duly authorized by all required corporate action
      on behalf of MDC Sub. This Agreement has been duly and validly executed and
      delivered by MDC Sub and, assuming due authorization, execution and delivery
      by
      CPB Inc., constitutes legal, valid and binding obligations of MDC Sub,
      enforceable against each of them in accordance with its terms.


    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    

    (c) MDC
      Partners is a corporation duly organized, validly existing and in good standing
      under the laws of Canada, with full corporate power and authority to own its
      property and to carry on its business all as and in the places where such
      properties are now owned or operated or such business is now being
      conducted.

    


    (d) MDC
      Partners has the full corporate power and authority to make, execute, deliver
      and perform this Agreement and the transactions contemplated hereby. The
      execution and delivery of this Agreement by MDC Partners and the consummation
      of
      the transactions contemplated hereby have been duly authorized by all required
      corporate action on behalf of MDC Partners. This Agreement has been duly and
      validly executed and delivered by MDC Partners and, assuming due authorization,
      execution and delivery by CPB Inc., constitutes legal, valid and binding
      obligations of MDC Partners, enforceable against each of them in accordance
      with
      its terms.

    


    (e) Each
      share of MDC Stock to be issued pursuant to the terms of this Agreement will
      be
      duly and validly authorized for issuance by MDC Partners, and upon consummation
      of the transactions contemplated hereby, will be duly and validly issued, fully
      paid and nonassessable, and not issued in violation of the preemptive rights
      of
      any past or present shareholder. All of the shares of MDC Stock to be issued
      pursuant to this Agreement will be (a) issued in transactions exempted under
      all
      applicable Canadian securities laws and in compliance with the rules and
      regulations of the Toronto Stock Exchange, and assuming the accuracy and
      truthfulness of an applicable Investment Representation Certificates to be
      delivered at Closing by the recipients of such MDC Stock, United States federal
      and state securities laws and (b) conditionally approved for listing on The
      NASDAQ National Market and the Toronto Stock Exchange, subject to official
      notice of issuance and/or the filing of customary documents and payment of
      listing fees.

     

    5.            
      Other
      Agreements.

     

    (a) As
      an
      inducement for MDC Sub to consummate the transactions contemplated by this
      Agreement and in consideration of the payment by MDC Sub of the Put/Call
      Purchase Price, each of the Employee Members hereby acknowledges and reaffirms
      his respective obligations under the provisions of the separate
      Non-Solicitation/Non-Servicing Agreement dated January 8, 2001 (each as
      thereafter amended on September 22, 2004, and as further amended in connection
      with this Agreement, the “Non-Solicit
      Agreements”),
      running to the benefit of the Company, Acquisition Co. and MDC Sub. It is
      understood that for purposes of the agreement referenced in the preceding
      sentence, each of the Employee Members shall be deemed to be employed by the
      Company for any period that he is either a full-time or part-time employee
      of
      the Company.


    
      
        
        

      

      
        5

        
          

        

      

      
        
        

      

    

    (b) Each
      of
      the parties hereto ratifies and acknowledges the rights of the Employee Members
      pursuant to the Non-Solicit Agreements.

     

    6.            
      Indemnity.

    


    (a) CPB
      Inc.
      hereby agrees to indemnify MDC Partners, MDC Sub and Acquisition Co. and their
      respective directors and officers (collectively “MDC
      Group”)
      against, and to protect, save and hold harmless each member of the MDC Group
      from, and to pay on behalf of or reimburse the respective member of the MDC
      Group as and when incurred for, any and all liabilities, obligations, losses,
      damages, penalties, demands, claims, actions, suits, judgments, settlements,
      penalties, interest, out-of-pocket costs, expenses and disbursements (including
      reasonable costs of investigation, and reasonable attorneys’, accountants’ and
      expert witnesses’ fees) of whatever kind and nature (collectively, “Losses”),
      that
      may be imposed on or incurred by any member of the MDC Group arising out of
      or
      in any way related to (i) any breach of any warranty or representation contained
      in Section 3 hereof or (ii) any action, demand, proceeding, investigation or
      claim by any third party against or affecting any member of the MDC Group which

      may give rise to or evidence the existence of or relate to a misrepresentation
      or breach of any of the representations and warranties contained in Section
      3
      hereof. 

    


    (b) MDC
      Sub
      and MDC Partners hereby agree to indemnify CPB Inc. against, and to protect,
      save and hold harmless CPB Inc. from, and to pay on behalf of or reimburse
      CPB
      Inc. as and when incurred for, any and all Losses that may be imposed on or
      incurred by CPB Inc. arising out of or in any way related to (i) any breach
      of
      any warranty or representation of MDC Sub or MDC Partners contained in Section
      4
      hereof or (ii) any action, demand, proceeding, investigation or claim by any
      third party against or affecting CPB Inc. which may give rise to or evidence
      the
      existence of or relate to a misrepresentation or breach of any of the
      representations and warranties contained in Section 4 hereof. 

    


    7.              Miscellaneous. 

    


    (a) 
      Each of
      MDC Sub and MDC Partners, on the one hand, and CPB Inc. and the Employee
      Members, on the other hand, shall pay its or his own expenses relating to the
      transactions contemplated by this Agreement, including, without limitation,
      the
      fees and expenses of their respective counsel and financial
      advisors.

    


    (b) The
      interpretation and construction of this Agreement, and all matters relating
      hereto (including, without limitation, the validity or enforcement of this
      Agreement), shall be governed by the laws of the State of New York without
      regard to any conflicts or choice of laws provisions of the State of New York
      that would result in the application of the law of any other
      jurisdiction.  

    


    (c) Subject
      to the provisions of the next sentence, no party to this Agreement shall issue
      any press release or other public document or make any public statement relating
      to this Agreement or the matters contained herein without obtaining the prior
      approval of MDC Sub and CPB Inc. Notwithstanding the foregoing, the foregoing
      provision shall not apply to the extent that MDC Partners is required to make
      any announcement or public disclosure relating to or arising out of this
      Agreement by virtue of the securities laws of the United States or Canada,
      or
      the rules and regulations promulgated thereunder, or the rules of the any stock
      exchange on which shares of MDC Partners are listed.


    
      
        
        

      

      
        6

        
          

        

      

      
        
        

      

    

    (d) Any
      notice, request, instruction or other document to be given hereunder by any
      party to any other party shall be in writing and shall be deemed to have been
      given (i) upon personal delivery, if delivered by hand or courier, (ii) three
      days after the date of deposit in the mails, postage prepaid, or (iii) the
      next
      business day if sent by facsimile transmission (if receipt is electronically
      confirmed) or by a prepaid overnight courier service, and in each case at the
      respective addresses or numbers set forth below or such other address or number
      as such party may have fixed by notice:

    


    If
      to MDC
      Sub or MDC Partners, addressed to:

     

    MDC
      Partners Inc.

    45
      Hazelton Avenue

    Toronto,
      Ontario

    Canada
      M5R 2E3

    Attention:
      Robert Dickson

    Fax:
      (416) 960-9555

    


    with
      a
      copy to:

    


    MDC
      Partners Inc.

    950
      Third
      Avenue

    New
      York,
      New York 10022

    Attention:
      Mitchell Gendel, General Counsel

    Fax:
      (212) 937-4365

    


     

    If
      to CPB
      Inc., addressed to:

     

    CPB
      Inc.

    3390
      Mary
      Street, Suite 300

    Miami,
      Florida 33133

    Attention:
      Chief Financial Officer

    Fax:
      (305) 854-3419

     

    


    Any
      party
      may change the address to which notices are to be sent by giving notice of
      such
      change of address to the other parties in the manner herein provided for giving
      notice.

     

    (e) This
      Agreement may not be transferred, assigned, pledged or hypothecated by any
      party
      hereto, other than by operation of law. This Agreement shall be binding upon
      and
      shall inure to the benefit of the parties hereto and their respective heirs,
      executors, administrators, successors and permitted assigns, as the case may
      be.


    
      
        
        

      

      
        7

        
          

        

      

      
        
        

      

    

    (f) In
      the
      event any provision of this Agreement is found to be void and unenforceable
      by a
      court of competent jurisdiction, the remaining provisions of this Agreement
      shall nevertheless be binding upon the parties with the same effect as though
      the void or unenforceable part had been severed and deleted.

    


    (g) This
      Agreement, including the other documents referred to herein, contains the entire
      understanding of the parties hereto with respect to the subject matter contained
      herein and therein. 

    


    (h) This
      Agreement may not be amended, supplemented or modified orally, but only by
      an
      agreement in writing signed by the all of the parties hereto.

    


    (i) The
      language used in this Agreement will be deemed to be the language chosen by
      the
      parties hereto to express their mutual intent, and no rule of law or contract
      interpretation that provides that in the case of ambiguity or uncertainty a
      provision should be construed against the draftsman will be applied against
      any
      party hereto.

    


    (j) This
      Agreement may be executed in one or more counterparts, and each such counterpart
      shall be deemed an original instrument, but all such counterparts taken together
      shall constitute but one agreement. Facsimile signatures shall constitute an
      original.

     

    


    *  *  *  *

     

    
      
        
        

      

      
        8

        
          

        

      

      
        
        

      

    

    IN
      WITNESS WHEREOF,
      the
      parties hereto have executed this Membership Interest Purchase Agreement, on
      the
      day and year first above written.

    


     

    
      	 	
              MDC
                ACQUISITION INC.

              


              By:
                _____________________________________

              Name:  

              Title: 

            
	 	 
	 	
              CPB
                ACQUISITION INC.

              


              By:
                _____________________________________

              Name:  

              Title: 

            
	 	 
	 	
              MDC
                PARTNERS INC.

              


              By:
                _____________________________________

              Name:  

              Title: 

            
	 	 
	 	
              CRISPIN & PORTER ADVERTISING,
                INC

               

              
                By:
                  _____________________________________

                Name:  

                Title: 

              

            
	 	 
	 	
              Employee Members:

               

              
                
                  By:
                    _____________________________________

                  Name:  

                  Title: 

                

              

            
	 	 
	 	
              By:_____________________

              Charles
                Porter

            
	 	 
	 	 
	 	
              By:_____________________

              Alex
                Bogusky

            
	 	 
	 	 
	 	
              By:_____________________

              Jeff
                Hicks

            
	 	 
	 	 
	 	
              By:_____________________

              Jeff
                Steinhour

            


    

    

      
        
          
          

        

        
          9