IMGN ImmunoGen Inc

On January 22, 2020, ImmunoGen, Inc. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Jefferies LLC, Cowen and Company, LLC and William Blair & Company, L.L.C., as representatives of the several underwriters (the “Underwriters”) named in Schedule 1 of the Underwriting Agreement, related to a public offering of 21,325,000 shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”), at a price of $4.25 per share less the underwriting discounts and commissions (the “Offering”). Under the terms of the Underwriting Agreement, the Company has granted the Underwriters an option, exercisable for 30 days, to purchase up to an additional 3,198,750 shares of Common Stock at the same price. The Offering is expected to close on January 27, 2020, subject to the satisfaction of customary closing conditions. The net proceeds to the Company are expected to be approximately $84.8 million after deducting underwriting discounts and commissions and estimated expenses associated with the Offering, assuming no exercise by the Underwriters of their option to purchase additional shares of Common Stock.

The Offering is being made pursuant to a prospectus supplement dated January 22, 2020 and an accompanying prospectus dated March 7, 2018, pursuant to the Company’s shelf registration statement on Form S-3 (File No. 333-223507), that was filed with the Securities and Exchange Commission on March 7, 2018 and became effective upon filing.

The Underwriting Agreement contains customary representations, warranties, and agreements by the Company, and customary conditions to closing, indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act of 1933, as amended, other obligations of the parties, and termination provisions.

A copy of the Underwriting Agreement is filed as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference. A copy of the opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. relating to the legality of the issuance and sale of the shares of Common Stock in the Offering is attached as Exhibit 5.1 to this Current Report on Form 8-K.

In connection with the Offering, certain information relating to Part II, Item 14 of the above referenced registration statement under the heading “Other Expenses of Issuance and Distribution” is being filed as Exhibit 99.1 to this Current Report on Form 8-K to be incorporated by reference into such registration statement.

The foregoing description of the Offering by the Company and the documentation related thereto does not purport to be complete and is qualified in its entirety by reference to such Exhibits.