Dean J. Mitchell - Jun 14, 2023 Form 4 Insider Report for ImmunoGen, Inc. (IMGN)

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	IMGN	Restricted Stock Unit	Award	$0	+13.1K		$0.00	13.1K	Jun 14, 2023	Common Stock	13.1K	$0.00	Direct	F1, F2
transaction	IMGN	Stock Option (right to buy)	Award	$0	+19.6K		$0.00	19.6K	Jun 14, 2023	Common Stock	19.6K	$17.72	Direct	F3, F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Id	Content
F1	The restricted stock units ("RSUs") were issued pursuant to the Issuer's Compensation Policy for Non-Employee Directors, as amended, and the 2018 Employee, Director and Consultant Equity Incentive Plan, as amended. Each RSU represents the contingent right to receive, upon vesting of the RSU, one share of the Issuer's common stock.
F2	The restricted stock units vest on the one-year anniversary of the date of grant, contingent upon the individual remaining a director as of the vesting date.
F3	The stock options were issued pursuant to the Issuer's Compensation Policy for Non-Employee Directors, as amended, and the 2018 Employee, Director and Consultant Equity Incentive Plan, as amended.
F4	The stock options vest ratably on each of 9/1/23, 12/1/23, 3/1/24, and 6/1/24, contingent upon the individual remaining a director as of each vesting date.