Exhibit 10.1
IMMUNOGEN, INC.
AMENDMENT TO STOCK OPTION
AGREEMENTS
This AMENDMENT is made as of the 24
th day of September, 2008 (the “Effective
Date”) to the Stock Option Agreements listed in
Exhibit A attached hereto (collectively, the
“Option Agreements”) between ImmunoGen, Inc., a
Massachusetts corporation (the “Company”), and Mitchel
Sayare, Ph.D. (the “Optionee”).
WHEREAS, the Company has adopted the
Restated Stock Option Plan (the “Restated Plan”) and
the 2006 Employee Director and Consultant Equity Incentive Plan
(the “2006 Plan”), to promote the interests of the
Company by providing an incentive for employees, directors and
consultants of the Company or its affiliates;
WHEREAS, the parties hereto
understand and agree that any terms used and not defined herein
have the meanings ascribed to such terms in the Restated Plan and
2006 Plan;
WHEREAS, Optionee was granted
incentive stock options and non-qualified stock options to purchase
shares of the Company’s common stock under the Restated Plan,
and incentive stock options to purchase shares of the
Company’s common stock under the 2006 Plan (together, the
“Affected Options”), which in the aggregate are covered
by the Option Agreements;
WHEREAS, on September 24, 2008
the Board of Directors of the Company approved a management
succession plan pursuant to which Optionee will step down as Chief
Executive Officer on December 31, 2008 and will retire as an
employee on the date of the 2009 annual meeting of shareholders of
the Company, and in connection with said management succession
plan, the Compensation Committee of the Board of Directors, as
Administrator of the Restated Plan and the 2006 Plan, authorized
the modification of certain terms of the Option Agreements such
that the Affected Options will continue to vest and be exercisable
in accordance with their terms for so long as Optionee remains
either an employee or director of the Company; and
WHEREAS, amendments to the Option
Agreements which are not adverse to the Optionee may be made by the
Administrator.
NOW, THEREFORE, in consideration of
the premises and the mutual covenants contained herein and for
other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the Opti
