Prepared by MERRILL CORPORATION




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Exhibit 4.8    
  



	NUMBER

NYU 79955	 	THIS CERTIFICATE IS

TRANSFERABLE IN

SAN FRANCISCO

OR NEW YORK	 	

 	 	COMMON STOCK

SHARES
	 	 	See reverse for certain definitions and statements of rights granted to each class of shares	 	INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE	 	CUSIP 170040 10 9
	

 	
 	

This Certifies That	
 	
SPECIMEN	
 	

 
	
 	
 	

is the owner of	
 	

 	
 	

 
	 	 	FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, PAR VALUE $.01 PER SHARE, OF
	 	 	CHIRON CORPORATION
	 	 	transferable on the books of the Corporation by the holder hereof, in person or by 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:	
 	


 



President and

Chief Executive Officer	
 	


 



Secretary
	

 	
 	

[SEAL]	
 	

 	
 	

Countersigned and Registered:

WELLS FARGO BANK MINNESOTA, N.A.

Transfer Agent and Registrar
	

 	
 	

 	
 	

 	
 	

By: 
 Authorized Signature







CHIRON CORPORATION  


    This Certificate and the shares represented hereby are subject to the laws of the State of Delaware and to the provisions of the Articles of Incorporation of
the Corporation as amended from time to time. The record holder of this Certificate may obtain from the Secretary of the Corporation, upon request and without charge, a copy of the statement of the
rights, preferences, privileges and restrictions granted to or imposed upon each class or series of capital stock of the Corporation and upon the holders thereof, the number of shares constituting
each class or series and the designation thereof. 


    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	 	................
	 	 	 	 	 	 	 	 	(Cust)        	 	(Minor)
	TEN ENT	 	—	 	as tenants by the entireties	 	 	 	under Uniform Gifts to Minors
	JT TEN	 	—	 	as joint tenants with right of	 	 	 	 	 	 
	 	 	 	 	survivorship and not as tenants	 	 	 	Act................................................
	 	 	 	 	in common	 	 	 	   (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 ADDRESSS, INCLUDING ZIP CODE, OF ASSIGNEE)
	


	


	

	
 	

Shares



of the Common Stock represented by the within certificate, and do hereby irrevocably constitute and appoint
                                         
       
Attorney to transfer the said shares 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 SIGNATURES(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED MEDALLION SIGNATURE GUARANTEE
PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15	 	 











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Exhibit 4.8