EX-4.3



 EXHIBIT 4.3 

SPECIMEN WARRANT CERTIFICATE 
  

			
	NUMBER	  	[    ] WARRANTS
	WA-	  	

 (THIS WARRANT WILL BE VOID IF NOT EXERCISED PRIOR TO 5:00 P.M. 

NEW YORK CITY TIME, THIRTY MONTHS FROM THE CLOSING DATE OF THE COMPANY’S INITIAL 

PUBLIC OFFERING) 
 CONTRAFECT
CORPORATION 
 CUSIP [            ] 

CLASS A WARRANT 
 THIS WARRANT CERTIFIES THAT,
for value received
                                        , or
registered agents, is the registered holder of a Warrant or Warrants expiring on a date which is thirty months from the closing date of the Company’s initial public offering (the “Warrant”), to purchase one fully paid and
non-assessable share of common stock, par value $0.0001 per share (the “Shares”), of CONTRAFECT CORPORATION, a Delaware corporation (the “Company”), for each Warrant evidenced by this Warrant Certificate. This Warrant Certificate
is subject to and shall be interpreted under the terms and conditions of the Class A Warrant Agreement (as defined below). 
 The
Warrant entitles the holder thereof to purchase from the Company, commencing upon the closing date of the Company’s initial public offering, such number of Shares at the price of $4.80 per share (the “Warrant Price”), upon surrender
of this Warrant Certificate and payment of the Warrant Price at the office or agency of American Stock Transfer & Trust Company, LLC (the “Warrant Agent”), such payment to be made by check made payable to the Warrant Agent, but
only subject to the conditions set forth herein and in the Warrant Agreement, dated [            ], 2014, between the Company and the Warrant Agent (the “Class A Warrant
Agreement”). In no event shall the registered holder(s) of this Warrant be entitled to receive a net-cash settlement, Shares or other consideration in lieu of physical settlement in Shares of the Company. The Class A 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 be adjusted, subject to certain conditions. 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. 
 This Warrant
will expire on the date first referenced above if it is not exercised prior to such date by the registered holder pursuant to the terms of the Class A Warrant Agreement or if it is not redeemed by the Company prior to such date. 

No fraction of a Share will be issued upon any exercise of a Warrant. If, upon exercise of a Warrant, a holder would be entitled to receive a
fractional interest in a Share, the Company will, upon exercise, issue or cause to be issued only the largest whole number of Shares issuable on such exercise (and such fraction of a Share will be disregarded). 

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(s) hereof or its assignee(s) 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(s) hereof in person or by
attorney duly authorized in writing, may be exchanged in the manner and subject to the limitations provided in the Class A 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(s) in exchange for this Warrant
Certificate, subject to the limitations provided in the Class A 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(s) as the absolute
owner(s) 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(s), 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(s)
to any of the rights of a stockholder of the Company. 
 From and after one year following its issuance, the Company reserves the right to
call the Warrant at any time, with a notice of call in writing to the holder(s) 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 $[            ] per share on each of 20 trading days within a 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. 
 COUNTERSIGNED: 
 AMERICAN STOCK
TRANSFER & TRUST COMPANY 
 WARRANT AGENT 
 BY: 

AUTHORIZED OFFICER 
 DATED: 

(Signature) 
 CHIEF EXECUTIVE OFFICER 

(Seal) 
 (Signature) 

SECRETARY 







 [REVERSE OF CERTIFICATE] 

SUBSCRIPTION FORM 
 To Be Executed
by the Registered Holder(s) in Order to Exercise Warrants 
 The undersigned Registered Holder(s) irrevocably elect(s) 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(s) of 

 

	
	  

	(PLEASE TYPE OR PRINT NAME(S) AND ADDRESS)
	
	  

	
	  

	
	  

	(SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER(S))

  

			
	and be delivered to	 	  

		 	(PLEASE PRINT OR TYPE NAME(S) 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(s) at the address(es) stated below: 

Dated: 
  

	
	  

	(SIGNATURE(S))
	
	  

	(ADDRESS(ES))
	
	  


  

	
	  

	(TAX IDENTIFICATION NUMBER(S))








 ASSIGNMENT 

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

For Value Received,
                                     hereby sell(s), assign(s), and
transfer(s) unto 
  

			
	  
	  	
	(PLEASE TYPE OR PRINT NAME(S) AND ADDRESS(ES))	  	
		
	  
	  	
		
	  
	  	
		
	  
	  	

 (SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER(S)) 
  

					
	and to be delivered to	 	  
	 	
		 	(PLEASE PRINT OR TYPE NAME(S) AND ADDRESS(ES))	 	
		
	     
	 	
		
	  
	 	

 (SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER(S)) 

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(S))

 NOTICE: THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY
PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER. 
 Signature(s) Guaranteed: 

 

			
	By	 	  


 THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS
AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15).