EX-32 8 a2139847zex-32.htm EXHIBIT 32
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EXHIBIT 32

Certification
Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
(Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code)

        Pursuant to section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and (b) of section 1350, chapter 63 of title 18, United States Code), each of the undersigned officers of ImmunoGen, Inc., a Massachusetts corporation (the "Company"), does hereby certify, to such officer's knowledge, that:

        The Annual Report for the year ended June 30, 2004 (the "Form 10-K") of the Company fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, and the information contained in the Form 10-K fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: August 20, 2004   /s/  MITCHEL SAYARE      
Mitchel Sayare Chairman of the Board of Directors, Chief Executive Officer and President

Dated: August 20, 2004
 
/s/  VIRGINIA A. LAVERY      
Virginia A. Lavery
Vice President, Finance and Treasurer



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