LOCKUP
AGREEMENT

     

    This Lockup
Agreement is being executed and delivered as of September 20, 2010 by
Michael Karfunkel (the “Shareholder”) in
favor of and for the benefit of Maiden Holdings Ltd., a Bermuda company (the
“Company”).

    


    RECITALS

    


    A.          Contemporaneously
with the execution and delivery of this Lockup Agreement, the Shareholder is
entering into an Warrant Exchange Agreement with the Company (the “Agreement”) pursuant
to which the Shareholder will acquire common shares of the Company (the “Shares”) in exchange
for the surrender of a Warrant (the “Exchange”).

    


    B.           In
connection with the Exchange (and as a condition to consummating the Exchange),
the Company has requested that the Shareholder enter into this Lockup Agreement;
and the Shareholder is entering into this Lockup Agreement in order to induce
the Company to enter into the Agreement and consummate the
Exchange.

     

    AGREEMENT

     

    In order
to induce the Company to enter into the Agreement and consummate the Exchange,
and in consideration of the issuance and delivery to the Shareholder of the
Shares pursuant to the Agreement, the Shareholder agrees as
follows:

     

    1.           Agreement by
Shareholder.

     

    (a)        
The Shareholder agrees with the Company that, beginning on the closing of the
Exchange (the “Closing”) and
continuing for a period of thirty six (36) months from the Closing, the
Shareholder will not, without the prior written consent of the Company, directly
or indirectly, (A) offer, pledge, sell, contract to sell, sell any option or
contract to purchase, purchase any option or contract to sell, grant any option,
right or warrant for the sale of, or otherwise dispose of or transfer any Shares
acquired by the Shareholder as a result of the Exchange or (B) enter into any
swap or any other agreement or any transaction that transfers, in whole or in
part, directly or indirectly, the economic consequence of ownership of such
Shares, whether any such swap transaction is to be settled by delivery of Shares
or other securities, in cash or otherwise.

     

    (b)         Notwithstanding
the foregoing, the Shareholder may transfer such Shares either during his
lifetime or upon death by will or intestacy to his immediate family or to a
trust if the beneficiaries of such trust are exclusively the Shareholder and/or
a member or members of his immediate family; provided, however, that prior
to any such transfer each transferee shall execute an agreement substantially
identical to this agreement and which shall be satisfactory to the Company,
pursuant to which each transferee shall agree to receive and hold such Shares,
subject to the provisions hereof, and there shall be no further transfer except
in accordance with the provisions hereof. For purposes of this paragraph,
“immediate family” shall mean spouse, lineal descendant, father, mother,
brother, sister or domestic partner of the transferor.

     

    The
Shareholder also agrees and consents to the entry of stop-transfer instructions
with the Company’s transfer agent against the transfer of such Shares except in
compliance with this Agreement.

     

    
      
         

      

      
         

        
          

        

      

      
         

      

    

     

    2.           Notices.
Any notice or other communication required or permitted to be delivered to the
Shareholder or the Company under this Lockup Agreement shall be in writing and
shall be deemed properly delivered, given and received when delivered (by hand,
by registered mail, by courier or express delivery service or by confirmed
facsimile) to the address or facsimile telephone number set forth beneath the
name of such party below (or to such other address or facsimile telephone number
as such party shall have specified in a written notice delivered in accordance
with this Section 2):

    


    if to the
Company:

    Maiden
Holdings, Ltd.

    131 Front
Street

    Hamilton
HM12 Bermuda

    Attention:
Secretary

    Fax:
(441) 292-0471

    


    if to the
Shareholder:

    Michael
Karfunkel

    American
Capital Acquisition Corporation

    59 Maiden
Lane

    New York,
NY 10038

    


    3.           Severability.
If any provision of this Lockup Agreement or any part of any such provision is
held under any circumstances to be invalid or unenforceable in any jurisdiction,
then (a) such provision or part thereof shall, with respect to such
circumstances and in such jurisdiction, be deemed amended to conform to
applicable laws so as to be valid and enforceable to the fullest possible
extent, (b) the invalidity or unenforceability of such provision or part thereof
under such circumstances and in such jurisdiction shall not affect the validity
or enforceability of such provision or part thereof under any other
circumstances or in any other jurisdiction, and (c) such invalidity of
enforceability of such provision or part thereof shall not affect the validity
or enforceability of the remainder of such provision or the validity or
enforceability of any other provision of this Lockup Agreement. Each provision
of this Lockup Agreement is separable from every other provision of this Lockup
Agreement, and each part of each provision of this Lockup Agreement is separable
from every other part of such provision.

     

    4.           Governing
Law. This Lockup Agreement shall be construed in accordance with, and
governed in all respects by, the laws of the State of New York, regardless of
the laws that might otherwise govern under applicable principles of conflicts of
laws thereof.

     

    
      
         

      

      
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    5.           Waiver.
No failure on the part of the Company to exercise any power, right, privilege or
remedy under this Lockup Agreement, and no delay on the part of the Company in
exercising any power, right, privilege or remedy under this Lockup Agreement,
shall operate as a waiver of such power, right, privilege or remedy; and no
single or partial exercise of any such power, right, privilege or remedy shall
preclude any other or further exercise thereof or of any other power, right,
privilege or remedy. The Company shall not be deemed to have waived any claim
arising out of this Lockup Agreement, or any power, right, privilege or remedy
under this Lockup Agreement, unless the waiver of such claim, power, right,
privilege or remedy is expressly set forth in a written instrument duly executed
and delivered on behalf of the Company; and any such waiver shall not be
applicable or have any effect except in the specific instance in which it is
given.

     

    6.           Captions.
The captions contained in this Lockup Agreement are for convenience of reference
only, shall not be deemed to be a part of this Lockup Agreement and shall not be
referred to in connection with the construction or interpretation of this Lockup
Agreement.

     

    7.    
     Further
Assurances. The Shareholder shall execute and/or cause to be delivered to
the Company such instruments and other documents and shall take such other
actions as the Company may reasonably request to effectuate the intent and
purposes of this Lockup Agreement.

     

    8.      
   Entire
Agreement. This Lockup Agreement and the other agreements referred to
herein set forth the entire understanding of the Shareholder and the Company
relating to the subject matter hereof and thereof and supersede all prior
agreements and understandings between any of such parties relating to the
subject matter hereof and thereof.

     

    9.         
Amendments.
This Lockup Agreement may not be amended, modified, altered, or supplemented
other than by means of a written instrument duly executed and delivered on
behalf of the Company and the Shareholder.

     

    10.        Assignment.
This Lockup Agreement and all obligations hereunder are personal to the
Shareholder and may not be transferred or assigned by the Shareholder at any
time except as provided in Section 1(b). The Company may assign its rights under
this Lockup Agreement to any entity in connection with any merger or sale or
transfer of all or substantially all of the Company’s assets.

     

    11.        Binding
Nature. Subject to Section 10, this Lockup Agreement will be binding upon
the Shareholder and the Shareholder’s representatives, executors,
administrators, estate, heirs, successors and assigns, and will inure to the
benefit of the Company and its successors and assigns.

     

    
      
         

      

      
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    In Witness
Whereof, the Shareholder and the Company have executed this Lockup
Agreement as of the date first above written.

     

    
      
        
          
            	
                    
                      SHAREHOLDER

                    

                  	 	 	
                    THE
      COMPANY

                  	 
	 	 	 	 	 
	 	 	 	
                    
                      Maiden
      Holdings Ltd.

                    

                  	 
	 	 	 	 	 
	 	 	 	 	 
	
                    
                      
                        
                          /s/
      Michael Karfunkel

                        

                      

                    

                  	 	By:	
                    
                      /s/
      Arturo M. Raschbaum

                    

                  	 
	
                    
                      
                        
                          MICHAEL
      KARFUNKEL

                        

                      

                    

                  	 	Name:	
                    Arturo
      M. Raschbaum

                  	 
	 	 	Title: 	President and Chief Executive Officer	 
	
                     

                  	 	
                  	
                     

                  	 


          

        

      

    

     

    
      
        
        

      

      
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