UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington,  D.C. 20549 

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): March 27, 2018

ImmunoGen, Inc.

(Exact name of registrant as specified in its charter)

830 Winter Street, Waltham,  MA 02451

(Address of principal executive offices)   (Zip Code)

Registrant's telephone number, including area code: (781)  895-0600

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is a an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter.

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

ITEM 1.01.  ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT

ITEM 5.02 – DEPARTURE OF DIRECTORS OR CERTAIN OFFICERS; ELECTION OF DIRECTORS; APPOINTMENT OF CERTAIN OFFICERS; COMPENSATORY ARRANGEMENTS OF CERTAIN OFFICERS

(a)  Not applicable.

(b)  On March 27, 2018, Mr. Daniel M. Junius, a Director of ImmunoGen, Inc. and our former President and Chief Executive Officer, notified our Chairman of the Board of Directors that he would not be standing for re-election at the annual meeting of shareholders to be held on June 20, 2018.

(c) – (f)  Not applicable.

ITEM 8.01 – OTHER EVENTS

On March 28, 2018, the Compensation Committee of our Board of Directors adopted an Incentive Compensation Recoupment Policy that his applicable to our executive officers, and such other of our senior executive team as may be determined by the committee.  If we determine that we must restate our financial results as reported in a periodic or other report filed with the SEC to correct an accounting error due to material noncompliance with any financial reporting requirement under the U.S. securities laws, we will seek to recover, at the direction of the Compensation Committee, after it has reviewed the facts and circumstances that led to the requirement of the restatement and the costs and benefits of seeking recovery, incentive compensation, both cash and equity-based, awarded or paid to an officer covered by the policy whose intentional misconduct caused or contributed to the need for the restatement for a fiscal period if a lower award or payment would have been made to such officer based on the restated financial results.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.