The execution, delivery and performance of this Agreement and the Ancillary Agreements to which it is a party by ImmunoGen have been duly and validly authorized by all necessary corporate action on behalf of ImmunoGen. This Agreement has been duly executed and delivered by ImmunoGen and constitutes the valid and binding obligation of ImmunoGen, enforceable in accordance with its terms, subject to the extent enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or other laws affecting the enforcement of creditors’ rights generally and by general equitable principles. Each Ancillary Agreement to which ImmunoGen is a party, when executed and delivered by ImmunoGen, will constitute the valid and binding obligation of ImmunoGen, enforceable against ImmunoGen in accordance with its terms, subject to the extent enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or other laws affecting the enforcement of creditors’ rights generally and by general equitable principles.