Execution
      Copy 

    


    


    MEMBERSHIP
      INTEREST PURCHASE AGREEMENT

    


    


    This
      Membership
      Interest Purchase Agreement (this
      “Agreement”)
      dated
      October 18, 2007 (this “Agreement”),
      is
      made by and among MDC/KBP Acquisition Inc., a Delaware corporation
      (“MDC/KBP”
or
      the
“Class
      A Member”),
      KBP
      Management Partners LLC, a Delaware limited liability company (“Management
      LLC”
or
      the
“Class
      B Member”;
      the
      Class
      B Member together with the Class A Member collectively referred to as the
“Members”
and
      individually a “Member”),
      MDC
      Corporate (US) Inc., a Delaware corporation (“MDC
      Corporate”),
      and
      KBP Holdings 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 LLC Agreement.

    


    


    WITNESSETH
      :

    


    WHEREAS,
      Management LLC desires to sell, and MDC Corporate desires to purchase, all
      of
      Management LLC's Class B Units (the “Purchased
      Interests”)
      in the
      Company, representing a 40% equity interest in the Company, pursuant to the
      provisions of this Agreement; and

     

    WHEREAS,
      Management LLC and MDC/KBP are parties to that certain Limited Liability Company
      Agreement of the Company dated January 28, 2004 (as amended, the “LLC
      Agreement”),
      which
      sets forth, among other things, the terms and conditions relating to transfer
      and ownership of the Class B Units upon exercise of a put or call option;


    


    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) Management
      LLC hereby sells, assigns and transfers to MDC Corporate, and MDC Corporate
      hereby purchases from Management LLC, 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 October 18, 2007, and 100% of Management LLC's Capital
      Account/Adjusted Capital Account (as such terms are defined the LLC Agreement)
      as in existence on October 18, 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 October 18, 2007, MDC/KBP and MDC Corporate shall cause the Company
        to
        close its books for income tax purposes, and there will be no allocation
        of
        gains or losses to Management LLC following the Closing Date. 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 Management LLC’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 Corporate of the Purchased Interests,
      MDC
      Corporate agrees to pay Management LLC an amount equal to the “Put/Call
      Purchase Price”,
      calculated and determined as follows:

    


    
      	 	
              (i)

            	
              At
                the Closing, an amount equal to $747,600 as the “Estimated
                TNW Payment”
                as of September 30, 2007, which amount represents a good faith estimate
                of
                the Applicable TNW (as defined in the LLC Agreement) multiplied by
                40% as
                the Applicable Percentage..

            


    

    


    
      	 	
              (ii)

            	
              In
                accordance with Section 10.4(a)(ii) of the LLC Agreement, within
                5
                Business Days following the determination of the audited Applicable
                TNW
                (but not later than sixty (60) days after the Closing), an amount
                equal to
                the audited Applicable TNW less the Estimated TNW Payment ($747,600),
                subject to adjustment as provided in Section 10.4(a)(vi) of the LLC
                Agreement.

            


    

    


    
      	 	
              (iii)

            	
              At
                the Closing, a “First
                Payment”
                in amount equal to $11,700,000, of which an amount equal to $8,775,000
                shall be paid in cash or immediately available funds and an amount
                equal
                to $2,925,000 shall be paid in the form of MDC Stock in accordance
                with
                Secion 2(a)(viii) of this Agreement. For purposes of this Agreement
                and
                determining the amount of the Put/Call Purchase Price payable at
                the
                Closing, (A) “YP”
                is deemed to be 2008; and (B) “PBT”
                for “YP-1” (2007) was estimated and deemed to be equal to $13.5 million.
                Notwithstanding such estimation of PBT for 2007, in calculating the
                amount
                of the “Second
                Payment”
                and “Final
                Payment”
                of the Put/Call Purchase Price payable to Management LLC, (1) PBT
                for YP-1
                (2007), YP (2008) and YP+1 (2009) shall be the actual amount of PBT
                for
                such calendar years, as determined and calculated in accordance with
                Section 10.4(b)(x) of the Agreement, and (2) the calculation of PBT
                in
                2007, 2008 and 2009 shall exclude any compensation expense relating
                to the
                grants of Additional MDC Shares referenced in Section 2(a)(vii) of
                this
                Agreement. 

            


    


    
      
        
        

      

      
        2

        
          

        

      

      
        
        

      

    


    
      	 	
              (iv)

            	
              In
                accordance with Section 10.4(a)(iv) of the LLC Agreement, within
                5
                Business Days following the determination of PBT for 2008, an amount
                equal
                to the Second Payment.

            


    

    


    
      	 	
              (v)

            	
              In
                accordance with Section 10.4(a)(v) of the LLC Agreement, within 5
                Business
                Days following the determination of PBT for 2009, an amount equal
                to the
                Final Payment.

            


    

    


    
      	 	
              (vi)

            	
              At
                the Closing, an additional payment in an amount equal to
                $2,711,000.

            


    

    


    
      	 	
              (vii)

            	
              As
                soon as practicable but not later than 30 days after the date hereof,
                MDC
                Partners Inc. will deliver Restricted Stock Grant Agreements,
                substantially in the form of Exhibit A hereto, for the issuance restricted
                shares of MDC Stock to employees of Kirshenbaum Bond & Partners LLC
                (as designated in writing on or prior to the Closing Date by Management
                LLC), having an aggregate Market Value equal to $250,000 (“Additional
                MDC Shares”),
                measured as of the 20 consecutive trading days ending five Business
                Days
                immediately prior to the Closing Date; provided,
                however,
                that the closing prices per share of MDC Stock shall be as reported
                in
                U.S. dollars on NASDAQ. All of the Additional MDC Shares will be
                issued
                pursuant to MDC Partners Inc.’s 2005 Stock Incentive Plan, and shall vest
                on the third anniversary of the date of grant, provided that the
                individual recipient of such Additional MDC Shares remains an employee
                of
                the Company or any of its affiliates as of the applicable vesting
                date.
                

            


    

    


    
      	 	
              (viii)

            	
              In
                accordance with Section 10.4(e) of the LLC Agreement relating to
                the
                payment of the Put/Call Purchase Price, an amount equal to 25% of
                the
                First Payment, Second Payment and Final Payment shall be made in
                shares of
                MDC Stock
                having a Market Value measured as of the 20 consecutive trading days
                ending five Business Days immediately prior to the date of the applicable
                payment (for purposes of the determining Market Value for the First
                Payment, the Closing Date shall be deemed the applicable payment
                date);
                provided,
                however,
                that the closing prices per share of MDC Stock shall be as reported
                in
                U.S. dollars on NASDAQ. The certificate representing the shares of
                MDC
                Stock to be issued as part of the First Payment shall be dated the
                date
                hereof and shall be delivered to Management LLC not later than ten
                (10)
                business days after the Closing Date. Notwithstanding the terms of
                clause
                G of the form of the “Investment Representation Certificate” required
                pursuant to Section 10.4(e) of the LLC Agreement, there shall be
                no
                contractual holding period for the shares of MDC Stock issued as
                part of
                the First Payment, the Second Payment or the Final
                Payment.

            


    


    
      
        
        

      

      
        3

        
          

        

      

      
        
        

      

    


    (b) 
      The
      parties hereto acknowledge and agree that the Put/Call Purchase Price to be
      paid
      by MDC Corporate pursuant to the terms and conditions set forth in Section
      2(a)
      above, will satisfy in
      full
      all
      payment obligations of the Class A Member, the Company and/or MDC Partners
      Inc. (“MDC
      Partners”)
      as set
      forth in the LLC Agreement.  Except as otherwise expressly provided herein,
      all of the terms of the LLC Agreement relating to the Put/Call Purchase Price
      shall continue to apply and govern the payments to be made pursuant to this
      Agreement, including without limitation the “Accounting Procedures” set forth in
      Section 10.4 of 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.

    


    (c) MDC
      Partners
      shall cause sufficient capital and/or MDC Stock, as the case may be, to be
      available to MDC Corporate to meet its obligations to pay the Put/Call Purchase
      Price under Section 2 of this Agreement. If
      MDC
      Corporate fails to meet its payment obligations under Section 2 hereof, then
      MDC
      Partners shall satisfy such payment obligations to the extent that MDC Corporate
      failed to do so.

    


    3. Representations
      and Warranties by Management LLC.
      Management LLC hereby represents and warrants to MDC Corporate as
      follows:

    


    (a) Management
      LLC is a limited liability company duly organized, validly existing and in
      good
      standing under the laws of the State 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.

     

    (b)
       Management
      LLC 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 Management LLC and the consummation by Management LLC of the
      transactions contemplated hereby have been duly authorized by all required
      action on behalf of Management LLC and its members. This Agreement has been
      duly
      and validly executed and delivered by Management LLC and, assuming due
      authorization, execution and delivery by MDC Corporate, constitutes a legal,
      valid and binding obligation of Management LLC, enforceable against it in
      accordance with its terms.

    


    (c)
       Management
      LLC is the owner of the Purchased Interests, 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 Corporate 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.


    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    


    (d) Except
      with respect to the individual allocations described in Schedule A hereto
      relating to pre-existing agreements to provide specified individuals with a
      percentage equity interest in Management LLC, (i) Management LLC hereby
      represents and warrants that it has not 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 and (ii) Management LLC agrees that, from and
      after
      the date hereof, no portion or proceeds of the Purchase Price shall be used
      to
      compensate or give any employee of the Company a bonus, gift, award or similar
      type of remuneration. 

     

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

    


    (a) MDC
      Corporate 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.
      

    


    (b) MDC
      Corporate 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 Corporate and the consummation
      of the transactions contemplated hereby have been duly authorized by all
      required corporate action on behalf of MDC Corporate. This Agreement has been
      duly and validly executed and delivered by MDC Corporate and, assuming due
      authorization, execution and delivery by Management LLC, constitutes legal,
      valid and binding obligations of MDC Corporate, enforceable against each of
      them
      in accordance with its terms.

    


    (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 Management LLC, 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 (including
      the
      Additional MDC Shares) 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 the applicable Investment
      Representation Certificates delivered 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

        
          

        

      

      
        
        

      

    


    5. Other
      Agreements.

     

    (a) As
      an
      inducement for MDC Corporate to consummate the transactions contemplated by
      this
      Agreement, each of Richard Kirshenbaum (“RK”)
      and
      Jonathan Bond (“JB”)
      hereby
      acknowledges and reaffirms his respective obligations under the provisions
      of
      the separate Non-Solicitation/Non-Servicing Agreement dated January 28, 2004
      (each as thereafter amended on September 22, 2004, the “Non-Solicit
      Agreements”),
      running to the benefit of the Company and MDC Corporate. It is understood that
      for purposes of the agreement referenced in the preceding sentence, RK and
      JB
      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.

    


    (b) MDC
      Partners Inc. acknowledges the rights of RK and JB pursuant to Section 3(c)
      of
      the Non-Solicit Agreements.

    6. [intentionally
      omitted]. 

     

    7. Indemnity.

    


    (a) Management
      LLC hereby agrees to indemnify each member of the 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
      Corporate hereby agrees to indemnify Management LLC against, and to protect,
      save and hold harmless Management LLC from, and to pay on behalf of or reimburse
      Management LLC as and when incurred for, any and all Losses that may be imposed
      on or incurred by Management LLC arising out of or in any way related to (i)
      any
      breach of any warranty or representation of MDC Corporate contained in Section
      4
      hereof or (ii) any action, demand, proceeding, investigation or claim by any
      third party against or affecting Management LLC 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.



    
      
        
        

      

      
        6

        
          

        

      

      
        
        

      

    


    8. Miscellaneous. 

    


    (a) 
      Each of
      MDC Corporate and MDC Partners, on the one hand, and Management LLC and RK/JB,
      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 Corporate and Management LLC. 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, or any announcement by
      any
      party or the companies pursuant to applicable law or regulations.

    


    (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
      Corporate or MDC Partners, addressed to:

     

    MDC
      Partners Inc.

    45
      Hazelton Avenue

    Toronto,
      Ontario

    Canada
      M5R 2E3

    Attention:
      Robert Dickson

    Fax:
      (416) 960-9555

     

    
      
        
        

      

      
        7

        
          

        

      

      
        
        

      

    


    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
        Management LLC, addressed to:

       

      c/o
        Kirshenbaum Bond & Partners

      160
        Varick Street

      New
        York,
        New York 10013

      Attention:
        Chief Financial Officer

      Fax
        (212)
        463-8643

       

      with
        a
        copy to:

      


      Richard
        Kirshenbaum

      c/o
        Kirshenbaum Bond & Partners

      160
        Varick Street

      New
        York,
        New York 10013

      Fax
        (212)
        463-8643

      


      and

      


      Jonathan
        Bond

      c/o
        Kirshenbaum Bond & Partners

      160
        Varick Street

      New
        York,
        New York 10013

      Fax
        (212)
        463-8643

      


      and

      


      Moses
        & Singer, LLP

      1301
        Avenue of the Americas

      New
        York,
        New York 10019

      Attention:
        Solomon P. Friedman, Esq.

      Fax:
        (212) 554-7700

    

     

    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.


    
      
        
        

      

      
        8

        
          

        

      

      
        
        

      

    


    (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.

    


    (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.

     

    


    *  *  *  *

     

    
      
        
        

      

      
        9

        
          

        

      

      
        
        

      

    


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

    


    
      	 	 	 
	 	MDC/KBP
              ACQUISITION INC.
	 
 	 
 	 
 
	 	By:  	 
	 	
              
Name:
	 	Title:


    

     

    
      	 	 	 
	 	MDC
              CORPORATE (US) INC.
	 
 	 
 	 
 
	 	By:  	 
	 	
              
Name:
	 	Title:


    

    


    
      	 	 	 
	 	MDC
              PARTNERS INC.
	 
 	 
 	 
 
	 	By:  	 
	 	
              
Name:
	 	Title:


    

     

    
      	 	 	 
	 	KBP
              MANAGEMENT PARTNERS LLC
	 
 	 
 	 
 
	 	By:  	 
	 	
              
Name:
	 	Title:


    

     

    
      	 	 	 
	 	KBP
              HOLDINGS LLC
	 
 	 
 	 
 
	 	By:  	 
	 	
              
Name:
	 	Title:


    

    


    Acknowledged
      and Agreed:

     

    
      	 	 	 	 
	By: 	 	 	 
	
              
                
 Richard
                Kirshenbaum

            	 	 	
            
	 	 	 	 
	By:	 	 	 
	
              
                
Jonathan
                Bond

            	 	 	 


    


    
      
        
        

      

      
        10