Immunogen (IMGN) 8-K Entry into a Material Definitive Agreement

Exhibit 99.1

The registrant is filing this Exhibit 99.1 for the purpose of incorporating the information set forth herein by reference into the registration statement on Form S-3 (File No. 333-216438) that was filed by the registrant with the Securities and Exchange Commission on March 3, 2017 and became effective on May 11, 2017.

The following table sets forth the estimated costs and expenses (other than the actual registration fee), other than underwriting discounts and commissions, payable by the registrant in connection with the sale of the securities being registered:

Legal Fees and Expenses	$	240,000
Accounting Fees and Expenses	50,000
Printing and Engraving Expenses	25,000
Miscellaneous Expenses	10,000
Total	$	325,000