EX-4.1



 Exhibit 4.1 
  






 
 ZQ|CERT#|COY|CLS|RGSTRY|ACCT#|TRANSTYPE|RUN#|TRANS# COMMON STOCK COMMON STOCK PAR VALUE $0.0001 THIS
CERTIFICATE IS TRANSFERABLE IN CANTON, MA, JERSEY CITY, NJ AND COLLEGE STATION, TX Certificate Shares Number * * 000000 ****************** ***000000 ***************** ZQ00000000 ****000000 **************** VISTERRA, INC. *****000000 ***************
******000000 ************** INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE ** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr.
Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David THIS CERTIFIES THAT Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr.
Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David
Sample**** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** CUSIP 92840Y 10 6 MR. SAMPLE & MRS. SAMPLE & MR. SAMPLE & MRS. SAMPLE Mr. Alexander David Sample
**** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David
Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample ****Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander SEE REVERSE FOR CERTAIN DEFINITIONS David Sample **** Mr.
Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample
**** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Sample **** Mr. Sample is the owner of
**000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares***
*000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****0
00000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****00
0000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000 ***ZERO HUNDRED THOUSAND ZERO HUNDRED AND ZERO***
000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****0000

00**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****00000 
0**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000 
**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000* 
*Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000** 
Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**S 
FULLY-PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF Visterra, Inc. (hereinafter called the “Company”), transferable on the books of the Company in person or by duly
authorized attorney, upon surrender of this Certificate properly endorsed. This Certificate and the shares represented hereby, are issued and shall be held subject to all of the provisions of the Certificate of Incorporation, as amended, and the
By-Laws, as amended, of the Company (copies of which are on file with the Company and with the Transfer Agent), to all of which each holder, by acceptance hereof, assents. This Certificate is not valid unless countersigned and registered by the
Transfer Agent and Registrar. Witness the facsimile seal of the Company and the facsimile signatures of its duly authorized officers. President Secretary VISTERRA, INC. INCORPORATION SEAL December 20, 2007 DELAWARE DATED DD-MMM-YYYY
COUNTERSIGNED AND REGISTERED: COMPUTERSHARE TRUST COMPANY, N.A. TRANSFER AGENT AND REGISTRAR, By AUTHORIZED SIGNATURE 1234567 Visterra PO BOX 43004, Providence, RI 02940-3004 MR A SAMPLE DESIGNATION (IF ANY) ADD 1 ADD 2 ADD 3 ADD 4 CUSIP XXXXXX XX X
Holder ID XXXXXXXXXX Insurance Value 1,000,000.00 Number of Shares 123456 DTC 12345678 123456789012345 Certificate Numbers Num/No. Denom. Total 1234567890/1234567890 1 1 1 1234567890/1234567890 2 2 2 1234567890/1234567890 3 3 3 1234567890/1234567890
4 4 4 1234567890/1234567890 5 5 5 1234567890/1234567890 6 6 6 Total Transaction 7 








	
	 

 VISTERRA, INC. 
 THE COMPANY WILL
FURNISH WITHOUT CHARGE TO EACH SHAREHOLDER WHO SO REQUESTS, A SUMMARY OF THE POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE, PARTICIPATING, OPTIONAL OR OTHER SPECIAL RIGHTS OF EACH CLASS OF STOCK OF THE COMPANY AND THE QUALIFICATIONS, LIMITATIONS OR
RESTRICTIONS OF SUCH PREFERENCES AND RIGHTS, AND THE VARIATIONS IN RIGHTS, PREFERENCES AND LIMITATIONS DETERMINED FOR EACH SERIES, WHICH ARE FIXED BY THE CERTIFICATE OF INCORPORATION OF THE COMPANY, AS AMENDED, AND THE RESOLUTIONS OF THE BOARD OF
DIRECTORS OF THE COMPANY, AND THE AUTHORITY OF THE BOARD OF DIRECTORS TO DETERMINE VARIATIONS FOR FUTURE SERIES. SUCH REQUEST MAY BE MADE TO THE OFFICE OF THE SECRETARY OF THE COMPANY OR TO THE TRANSFER AGENT. THE BOARD OF DIRECTORS MAY REQUIRE THE
OWNER OF A LOST OR DESTROYED STOCK CERTIFICATE, OR HIS LEGAL REPRESENTATIVES, TO GIVE THE COMPANY A BOND TO INDEMNIFY IT AND ITS TRANSFER AGENTS AND REGISTRARS AGAINST ANY CLAIM THAT MAY BE MADE AGAINST THEM ON ACCOUNT OF THE ALLEGED LOSS OR
DESTRUCTION OF ANY SUCH 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                                    
           
		 		 		 	(Cust)                                   
              (Minor)                 
	TEN ENT	 	- as tenants by the entireties	 		 	under Uniform Gifts to Minors Act                            
              
		 		 		 	(State)                   
	JT TEN	 	- as joint tenants with right of	 	UNIF TRF MIN ACT	 	-                                  Custodian 
(until age                               )
		 	  survivorship and not as tenants	 		 	(Cust)                                   
                                         
  
		 	  in common	 		 	                   under Uniform Transfers to Minors Act       
          
		 		 		 	(Minor)                                   
                                   (State)     
 
		 		 		 	

 Additional abbreviations may also be used though not in the above list. 

 

							
		 		 		 	PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE
	For value received,	 	  
	 	hereby sell, assign and transfer unto  	 	 

  
  

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING POSTAL 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 stock on the books of the within-named Incorporation with full power of substitution in the premises.	 	

 
  

													
	Dated:	 	  
	 	20	 	            
	 		  	Signature(s) Guaranteed: Medallion Guarantee Stamp
		 		 		 		 		 	 	  	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.
	Signature:	 	  
	 	 	  
	  
 Signature:
	 	  

     
	 	 	  
		 	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.