FORM OF CURIS COMMON STOCK CERTIFICATE



 Exhibit 4.1 
  

[FRONT OF CURIS STOCK CERTIFICATE] 
  
 [LOGO] 
 CURIS, INC. 
 INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE 
  

			
	 NUMBER
	 	SHARES
	 	 	SEE REVERSE FOR CERTAIN DEFINITIONS
	 	 	CUSIP 231269 10 1

  
 THIS CERTIFIES THAT 
  
  
  
 is the owner of 
  
 FULLY-PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, PAR VALUE $.01 PER SHARE, OF 
  
 Curis, Inc., transferable upon the books of the corporation in person or by attorney upon surrender of this certificate duly endorsed or assigned. This certificate and
the shares represented hereby are subject to the laws of the State of Delaware and to the Certificate of Incorporation and by-laws of the corporation. This certificate is not valid until countersigned by the Transfer Agent and registered by the
Registrar. 
  
 IN WITNESS WHEREOF, Curis, Inc. has caused its
corporate seal to be hereunto affixed and this certificate to be singed by its duly authorized officers. 
  
 Dated: 
  

					
	 TREASURER
	 	[SEAL]	 	CHIEF EXECUTIVE OFFICER
	 	 	CURIS, INC.	 	 
	 	 	CORPORATE	 	 
	 	 	SEAL	 	 
	 	 	2000	 	 
	 	 	DELAWARE	 	 

  
 COUNTERSIGNED AND REGISTERED:

 MELLON INVESTOR SERVICES LLC 
 TRANSFER AGENT AND REGISTRAR.

  
 BY 
  
 AUTHORIZED SIGNATURE 
  









 [BACK OF CURIS STOCK CERTIFICATE] 
  
 CURIS, INC. 
  
 THE CORPORATION IS AUTHORIZED TO ISSUE MORE THAN ONE CLASS OR SERIES OF STOCK. A COPY OF THE PREFERENCES, POWERS, QUALIFICATIONS AND RIGHTS OF EACH CLASS
AND SERIES WILL BE FURNISHED BY THE CORPORATION UPON WRITTEN REQUEST AND WITHOUT CHARGE. 
  
 The following abbreviations, when used in the in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: 
  

							
	 TEN COM —
	 	as tenants in common	 	UNIF GIFT MIN ACT —	 	                  Custodian
                

	 TEN ENT  —
	 	as tenants by the entireties	 	 	 	   (Cust)                        (Minor)

	 JT TEN      —
	 	as joint tenants with rights of survivorship and not as tenants in common.	 	 	 	 Under Uniform Gifts to Minors

	 	 	 	 	 	   Act
                                       
 

	 	 	 	 	 	(State)    

  
 Additional
abbreviations may also be used though not in the above list. 
  
 For value
received,
                                        
                 hereby sell, assign and transfer unto 
  
 PLEASE INSERT SOCIAL SECURITY OR OTHER 
 IDENTIFYING NUMBER OF ASSIGNEE

  
                                       
                                        
                                        
                                        
                                        
             
 PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING ZIP CODE OF ASSIGNEE

  
                                       
                                        
                                        
                                        
                                        
             
  
                                       
                                        
                                        
                                        
                                        
             
  
                                       
                                        
                                        
                                        
                                        
             
 Shares of the Capital Stock represented by the within Certificate, and do
hereby irrevocably constitute and appoint 
  
                                       
                                        
                                        
                                        
                                        
             
 Attorney to transfer the said stock on the books of the within-named
Corporation with full power of substitution in the premises. 
  
 Dated
                                 
  

			
	

	NOTICE:	 	THE SIGNATURE 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:	 	  

	 	 
	 	 	THE SIGNATURE(S) SHOULD 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.