Immunogen (IMGN) Form 3 IMMUNOGEN / Stuart A Arbuckle ownership change

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

Arbuckle Stuart A

(Last) (First) (Middle)

C/O VERTEX PHARMACEUTICALS INCORPORATED

50 NORTHERN AVE

(Street)

BOSTON MA 02210

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
01/23/2018

3. Issuer Name and Ticker or Trading Symbol
IMMUNOGEN INC [ IMGN ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Deferred Share Unit	04/01/2018(2)(3)	(2)	Common Stock(2)	6,500	0(1)	D
Stock Option (right to buy)	03/01/2018(4)	01/23/2028	Common Stock	4,167	8.2	D

Explanation of Responses:

1. The deferred share units were issued pursuant to the Issuer's Compensation Policy for Non-Employee Directors and are convertible into Common Stock on a one-to-one basis

2. The vested deferred share units are to be settled 100% in shares of the Common Stock of the Company upon the reporting person's retirement from the Board of Directors.

3. The deferred share units vest ratably over a three year period in quarterly increments beginning on April 1, 2018, contingent upon the individual remaining a director as of each vesting date.

4. Exercisable as to 2,084 shares commencing on March 1, 2018 and 2,083 shares commencing on June 1, 2018, contingent upon the individual remaining a director as of each vesting date.

	/s/ Craig Barrows, attorney in fact	01/24/2018
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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