Exhibit
      4.3 

     

    
      	
              NUMBER

              ________-

            	 	
              (SEE
                REVERSE SIDE FOR LEGEND)

              THIS
                WARRANT WILL BE VOID IF NOT EXERCISED PRIOR TO 5:00 P.M. NEW YORK
                CITY
                TIME, __________, 2011

            	 	
              WARRANTS

            


    

    ALYST
      ACQUISITION CORP.

    CUSIP
      _______

     

    WARRANT

     

    THIS
      CERTIFIES THAT, for value received 

    


    is
      the
      registered holder of a Warrant or Warrants expiring ________, 2011 (the
“Warrant”) to purchase one fully paid and non-assessable share of Common Stock,
      par value $.0001 per share (“Shares”), of Alyst Acquisition Corp., a Delaware
      corporation (the “Company”), for each Warrant evidenced by this Warrant
      Certificate. The Warrant entitles the holder thereof to purchase from the
      Company, commencing on the later of (i) the Company’s completion of a merger,
      capital stock exchange, asset acquisition or other similar business combination
      and (ii) ______________, 2008, such number of Shares of the Company at the
      price
      of $5.00 per share, upon surrender of this Warrant Certificate and payment
      of
      the Warrant Price at the office or agency of the Warrant Agent, Continental
      Stock Transfer & Trust Company, but only subject to the conditions set forth
      herein and in the Warrant Agreement between the Company and Continental Stock
      Transfer & Trust Company. The Company shall not be obligated to deliver any
      securities pursuant to the exercise of a Warrant and shall have no obligation
      to
      settle a Warrant exercise unless a registration statement under the Securities
      Act of 1933, as amended, (the “Act”) with respect to the Common Stock is
      effective, subject to the Company satisfying its obligations under Section
      7.4
      of the Warrant Agreement to use its best efforts. In the event that a
      registration statement with respect to the Common Stock underlying a Warrant
      is
      not effective under the Act, the holder of such Warrant shall not be entitled
      to
      exercise such Warrant and such Warrant may have no value and expire worthless.
      In no event will the Company be required to net cash settle the warrant
      exercise. The Warrant Agreement provides that upon the occurrence of certain
      events the Warrant Price and the number of Warrant Shares purchasable hereunder,
      set forth on the face hereof, may, subject to certain conditions, be adjusted.
      The term Warrant Price as used in this Warrant Certificate refers to the price
      per Share at which Shares may be purchased at the time the Warrant is
      exercised.

     

    No
      fraction of a Share will be issued upon any exercise of a Warrant. If the holder
      of a Warrant would be entitled to receive a fraction of a Share upon any
      exercise of a Warrant, the Company shall, upon such exercise, round up to the
      nearest whole number the number of Shares to be issued to such
      holder.

     

    Upon
      any
      exercise of the Warrant for less than the total number of full Shares provided
      for herein, there shall be issued to the registered holder hereof or the
      registered holder’s assignee a new Warrant Certificate covering the number of
      Shares for which the Warrant has not been exercised.

     

    Warrant
      Certificates, when surrendered at the office or agency of the Warrant Agent
      by
      the registered holder hereof in person or by attorney duly authorized in
      writing, may be exchanged in the manner and subject to the limitations provided
      in the Warrant Agreement, but without payment of any service charge, for another
      Warrant Certificate or Warrant Certificates of like tenor and evidencing in
      the
      aggregate a like number of Warrants.

     

    Upon
      due
      presentment for registration of transfer of the Warrant Certificate at the
      office or agency of the Warrant Agent, a new Warrant Certificate or Warrant
      Certificates of like tenor and evidencing in the aggregate a like number of
      Warrants shall be issued to the transferee in exchange for this Warrant
      Certificate, subject to the limitations provided in the Warrant Agreement,
      without charge except for any applicable tax or other governmental
      charge.

     

    The
      Company and the Warrant Agent may deem and treat the registered holder as the
      absolute owner of this Warrant Certificate (notwithstanding any notation of
      ownership or other writing hereon made by anyone), for the purpose of any
      exercise hereof, of any distribution to the registered holder, and for all
      other
      purposes, and neither the Company nor the Warrant Agent shall be affected by
      any
      notice to the contrary.

     

    This
      Warrant does not entitle the registered holder to any of the rights of a
      stockholder of the Company.

     

    The
      Company reserves the right to call the Warrant at any time prior to its
      exercise, with the prior consent of Jesup & Lamont Securities Corporation,
      with a notice of call in writing to the holders of record of the Warrant, giving
      30 days’ notice of such call at any time after the Warrant becomes exercisable
      if the last sale price of the Shares has been at least $11.50 per share on
      each
      of 20 trading days within any 30 trading day period ending on the third business
      day prior to the date on which notice of such call is given. The call price
      of
      the Warrants is to be $.01 per Warrant. Any Warrant either not exercised or
      tendered back to the Company by the end of the date specified in the notice
      of
      call shall be canceled on the books of the Company and have no further value
      except for the $.01 call price.

    

      
        	
                By   
                  

              	 	
                 

              	 	
                 

              
	
                 

              	
                Secretary

              	
                 

              	
                Chairman
                  of the Board

              	
                 

              


      

    

     

    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

     

    SUBSCRIPTION
      FORM

    To
      Be
      Executed by the Registered Holder in Order to Exercise Warrants

    


    The
      undersigned Registered Holder irrevocably elects to exercise
      ______________ Warrants represented by this Warrant Certificate, and to
      purchase the shares of Common Stock issuable upon the exercise of such Warrants,
      and requests that Certificates for such shares shall be issued in the name
      of

     

    
      	
              
                

                (PLEASE TYPE OR PRINT NAME AND ADDRESS)

               

            
	 
	 


    

    (SOCIAL
      SECURITY OR TAX IDENTIFICATION NUMBER)

     

    
      
        and
          be delivered to
          _____________________________________________________________________________________

      

      (PLEASE
        PRINT OR TYPE NAME AND ADDRESS)

       

        
          

        

      

    

    and,
      if such number of Warrants shall not be all the
      Warrants evidenced by this Warrant Certificate, that a new Warrant Certificate
      for the balance of such Warrants be registered in the name of, and delivered
      to,
      the Registered Holder at the address stated below:

    
      	 	 	 
	Dated:
              	 	 
	
              
                

              

            	
              
(SIGNATURE)
	 	 
	 	
              
(ADDRESS)
	 	 
	 	
              
                

              

               

            
	 	
              
(TAX
              IDENTIFICATION NUMBER)


    

     

    ASSIGNMENT

     

    To
      Be
      Executed by the Registered Holder in Order to Assign Warrants

    


    For
      Value
      Received, _______________________ hereby sell, assign, and transfer unto


    


    
      	
              
                

                (PLEASE TYPE OR PRINT NAME AND ADDRESS)

               

            
	 
	 


    

    (SOCIAL
      SECURITY OR TAX IDENTIFICATION NUMBER)

     

    and
      be
      delivered to
      _____________________________________________________________________________________

    (PLEASE
      PRINT OR TYPE NAME AND ADDRESS)

    


    ______________________
      of the Warrants represented by this Warrant Certificate, and hereby irrevocably
      constitute and appoint _________________________________ Attorney to transfer
      this Warrant Certificate on the books of the Company, with full power of
      substitution in the premises.

    
      	 	 	 
	Dated:	 	 
	
              
                

              

            	
              

              (SIGNATURE)

            
	 	 


    

     

    
      THE
        SIGNATURE TO THE ASSIGNMENT OF THE SUBSCRIPTION FORM MUST CORRESPOND TO THE
        NAME
        WRITTEN UPON THE FACE OF THIS WARRANT CERTIFICATE IN EVERY PARTICULAR, WITHOUT
        ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATSOEVER, AND MUST BE GUARANTEED
        BY A
        COMMERCIAL BANK OR TRUST COMPANY OR A MEMBER FIRM OF THE AMERICAN STOCK
        EXCHANGE, NEW YORK STOCK EXCHANGE, PACIFIC STOCK EXCHANGE OR CHICAGO STOCK
        EXCHANGE.