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Exhibit 4.1  



	COMMON STOCK	 	COMMON STOCK





	NUMBER	 	 	 	 	 	SHARES	 	 
	XTNT001	 	 	 	 	 	 	 	 
	XTENT

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE
	

 	
 	

 	
 	

 	
 	
CUSIP 984141 10 1	
 	

 
	 	 	 	 	 	 	SEE REVERSE FOR

CERTAIN DEFINITIONS	 	 
	

 	
 	
THIS CERTIFIES that	
 	

 	
 	

 	
 	

 
	

    	
 	

 	
 	

 	
 	

 	
 	

 
	

 	
 	

is the owner of	
 	

 	
 	

 	
 	

 
	

 	
 	

FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK,

$0.001 PAR VALUE PER SHARE, OF
 XTENT, INC.	
 	

 
	

 	
 	
transferable only on the books of the Corporation by the holder hereof in person or by a duly authorized attorney upon surrender of this Certificate properly endorsed. This Certificate is not valid until countersigned
by the Transfer Agent and registered by the Registrar.	
 	

 
	

 	
 	

WITNESS the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.	
 	

 
	

 	
 	

Dated:	
 	

 	
 	

 	
 	

 
	

 	
 	

/s/  J. CASEY MCGLYNN    

SECRETARY	
 	

/s/  GREGORY D. CASCIARO    

PRESIDENT AND CHIEF EXECUTIVE OFFICER
	

 	
 	

 	
 	

COUNTERSIGNED AND REGISTERED:	
 	

 
	 	 	 	 	COMPUTERSHARE TRUST COMPANY, N.A.
	 	 	 	 	TRANSFER AGENT AND REGISTRAR,
	 	 	 	 	By
	 	 	 	 	/s/  STEPHEN CESSO      
	 	 	 	 	 	 	AUTHORIZED SIGNATURE

	 	 









  
 

    XTENT, INC.    
    


        THE CORPORATION WILL FURNISH WITHOUT CHARGE TO EACH STOCKHOLDER WHO SO REQUESTS THE POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE PARTICIPATING, OPTIONAL OR OTHER
SPECIAL RIGHTS OF EACH CLASS OF STOCK OR SERIES THEREOF AND THE QUALIFICATIONS, LIMITATIONS OR RESTRICTIONS OF SUCH PREFERENCES AND/OR
RIGHTS. SUCH REQUEST MUST BE MADE TO THE CORPORATION'S SECRETARY AT THE PRINCIPAL EXECUTIVE OFFICE OF THE CORPORATION. 


        Keep
this Certificate in a safe place. If it is lost, stolen or destroyed, the Corporation will require a bond of indemnity as a condition to the issuance of a replacement certificate. 


        The
following abbreviations, when used 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 right of survivorship and not as tenants in common	 	 	 	 	 	 	under Uniform Gifts to Minors Act

    
 (State)
	

 	

 	
 	

 	
 	

 	
 	

UNIF TRF MIN ACT	

—	
 	

	
 	

Custodian (until age       )	
 	


	 	 	 	 	 	 	 	 	 	 	(Cust)	 	 	 	(Minor)
	 	 	 	 	 	 	 	 	 	 	under Uniform Transfers 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 Common Stock represented by the within Certificate, and do(es) 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	
 	

    
	
 	

 
	

 	
 	
X	
 	

    

	 	 	X	 	    

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

 













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XTENT, INC.