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C. K. COOPER & COMPANY
Our Insight, Your Growth

 
July 29, 2010
 
Mr. Dwight Babcock
IsoRay, Inc.
350 Hills Street, Suite 106
Richland, WA 99354
 
RE: Amendment of Sales Agreement, Dated April 22, 2010
 
Dear Mr. Babcock:
 
Reference is hereby made to that certain Sales Agreement between us, dated as of
April 22, 2010 (the "Sales Agreement"). For good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereby
agree that the Sales Agreement shall be amended as follows:
 
1. Section 11(d) of the Sales Agreement is hereby amended in its entirety to
read as follows: "Unless earlier terminated pursuant to this Section 11, this
Agreement shall automatically terminate upon the first to occur of (i) December
31, 2010, and (ii) the issuance and sale of the Maximum Amount of Shares through
CKCC pursuant to this Agreement."
 
This letter shall be construed in connection with and as part of the Sales
Agreement, and all terms, conditions, and covenants set forth in the Sales
Agreement and each other instrument or agreement referred to therein, as
applicable, except as herein amended, are hereby ratified and confirmed and
shall remain in full force and effect.
 
This letter may be executed in two or more counterparts, each of which shall be
deemed an original, but all of which together shall constitute one and the same
instrument.
 
[Signature Page Follows]
 
 
18300 Von Karman Ave., Suite 700, Irvine, California 92612
TEL: 949 477-9300  FAX: 949 477-9211  TOLL-FREE: 888
477-9301  administration@ckcooper.com
 

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To acknowledge your acceptance of the terms of this letter, please so indicate
in the space provided below.
 

    Sincerely,               C. K. Cooper & Company, Inc.          
 
 
/s/ Alexander G. Montano       Alexander G. Montano      
Managing Director
 

 
 
Accepted and agreed as of the date first above written:
 
 
IsoRay, Inc.
 
/s/ Dwight Babcock
Dwight Babcock
Chief Executive Officer
 

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