As filed with the Securities and Exchange Commission On January 5, 2001 Registration No. 33- SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 IMMUNOGEN, INC. ------------------------------------------------------ (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER) MASSACHUSETTS 04-2726691 --------------------------------------------------------------------------- (STATE OR OTHER JURISDICTION OF (I.R.S. EMPLOYER INCORPORATION OR ORGANIZATION) IDENTIFICATION NO.) 128 SIDNEY STREET, CAMBRIDGE, MASSACHUSETTS 02139 ------------------------------------------------- (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES) IMMUNOGEN, INC. RESTATED STOCK OPTION PLAN ------------------------------------------ (FULL TITLE OF THE PLAN) Mitchel Sayare Chairman of the Board and Chief Executive Officer ImmunoGen, Inc. 128 Sidney Street Cambridge, Massachusetts 02139 ------------------------------ (NAME AND ADDRESS OF AGENT FOR SERVICE) (617) 995-2500 -------------- (TELEPHONE NUMBER, INCLUDING AREA CODE, OF AGENT FOR SERVICE) Please send copies of all communications to: Jonathan L. Kravetz, Esq. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. One Financial Center Boston, MA 02111 (617) 542-6000 1 CALCULATION OF REGISTRATION FEE Proposed Proposed Title of maximum maximum securities Amount offering aggregate Amount of to be to be price per offering registration registered registered(1) unit(4) price(4) fee Common Stock, $.01 par value 472,163 (2) $ 8.14 $ 3,843,407 $ 960.85 Common Stock, $.01 par value 852,837 (3) 20.50 17,483,158 $4,370.79 --------- TOTAL 1,325,000 $21,326,566 $5,331.64 ========= =========== ========= (1) The number of shares of common stock, par value $.01 per share (the "Common Stock"), consists of the aggregate number of additional shares not previously registered which may be sold upon the exercise of options which have been granted and/or may hereafter be granted under the ImmunoGen, Inc. Restated Stock Option Plan (the "Plan"). The maximum number of shares which may be sold upon the exercise of such options granted under the Plan is subject to adjustment in accordance with certain anti-dilution and other provisions of the Plan. Accordingly, pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement covers, in addition to the number of shares stated above, an indeterminable number of shares which may be subject to grant or otherwise issuable after the operation of any such anti-dilution and other provisions. (2) Consists of the aggregate number of shares of Common Stock which may be sold upon the exercise of options which previously have been granted under the Plan. (3) Consists of the aggregate number of shares of Common Stock which may be sold upon the exercise of options which may hereafter be granted under the Plan. (4) This calculation is made solely for the purpose of determining the registration fee pursuant to the provisions of Rule 457(h) under the Securities Act as follows: (i) in the case of shares of Common Stock which may be purchased upon exercise of outstanding options, the fee is calculated on the basis of the price at which the options may be exercised; and (ii) in the case of shares of Common Stock for which options have not yet been granted and the option price of which is therefore unknown, the fee is calculated on the basis of the average high and low sales prices per share of the Common Stock on the Nasdaq National Market System as of a date January 3,2001. EXPLANATORY NOTE This Registration Statement relates to the registration of 1,325,000 additional shares of Common Stock authorized for issuance under the Plan. In accordance with the instructional Note to Part I of Form S-8 as promulgated by the Securities and Exchange Commission, the information specified by Part I of Form S-8 has been omitted from this Registration Statement on Form S-8 for offers of Common Stock pursuant to the Plan. The prospectuses filed as a part of the Company's registration statements No. 33-41534 and No. 33-73544 may no longer be used for reofferings and resales of Common stock because the information in such prospectuses is no longer accurate. 2 PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE. - ----------------------------------------------- The following documents filed by the Registrant with the Securities and Exchange Commission (the "Commission") are incorporated herein by reference: (a) The Registrant's annual report on Form 10-K (Commission File No. 0-17999) for the fiscal year ended June 30, 2000. (b) The Registrant's quarterly report on Form 10-Q (Commission File No. 0-17999) for the quarter ended September 30, 2000. (c) The Registrant's current reports on Form 8-K filed with the Commission on September 11, 2000, October 10, 2000 and November 16, 2000 and on Form 8-K/A filed with the Commission on October 10, 2000. (d) The description of the Common Stock included in the Registrant's Registration Statement on Form 8-A under the Securities Exchange Act of 1934 (File No. 0-17999), filed with the Commission on September 22, 1989, including any amendment or report filed for the purpose of updating such description. (e) The Registrant's proxy materials on Schedule 14A filed with the Commission October 12, 2000. All reports and other documents subsequently filed by the Registrant with the Commission pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-effective amendment which indicates that all securities covered by this Registration Statement have been sold or which deregisters all such securities then remaining unsold shall be deemed to be incorporated by reference herein and to be a part hereof from the date of the filing of such reports and documents. ITEM 4. DESCRIPTION OF SECURITIES. - ---------------------------------- Not applicable. ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL. - ---------------------------------------------- Not applicable. ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS. - ------------------------------------------------- Incorporated herein by reference from the Registrant's Registration Statement on Form S-3 (Registration No. 33-48042), as amended. ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED. - ------------------------------------------- Not applicable. ITEM 8. EXHIBITS. - ---------------- EXHIBIT NO. DESCRIPTION - -------------------------- (4.1) Form of Common Stock Certificate (previously filed as Exhibit 4.2 to the Registrant's Registration Statement on Form S-1, Registration No. 33-31219, as amended, and incorporated herein by reference) (4.2) Restated Articles of Organization of the Registrant (previously filed as Exhibit 3.1 to the Registrant's Registration Statement on Form S-1, Registration No. 33-38883, as amended, and incorporated herein by reference) 3 (4.3) By-Laws, as amended, of the Registrant (previously filed as Exhibit 3.2 to the Registrant's annual report on Form 10-K for the fiscal year ended June 30, 1990, and incorporated herein by reference) (5) Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., with respect to the legality of the shares being registered (23.1) Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in opinion of counsel filed as Exhibit 5) (23.2) Consent of PricewaterhouseCoopers (24) Power of Attorney to file future amendments (included on the signature page of this Registration Statement) (99) ImmunoGen, Inc. Restated Stock Option Plan, as amended. ITEM 9. UNDERTAKINGS. - -------------------- (a) The undersigned Registrant hereby undertakes: (1) to file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement: (i) to include any prospectus required by Section 10(a)(3) of the Securities Act of 1933; (ii) to reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement; (iii) to include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement; Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) of Regulation C under the Securities Act of 1933, as amended, if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective Registration Statement; provided, however, that paragraphs (a)(1)(i) and (ii) shall not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed by the registrant pursuant to section 13 or section 15(d) of the Securities and Exchange Act of 1934 that are incorporated by reference in the registration statement. (2) that, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. (3) to remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering. (b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in this Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. (c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been 4 advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue. 5 SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of Massachusetts, on January 4,2001. IMMUNOGEN, INC. /s/ Mitchel Sayare ----------------------------------- By: Mitchel Sayare Chairman of the Board and Chief Executive Officer We, the undersigned officers and directors of ImmunoGen, Inc., hereby severally constitute and appoint Mitchel Sayare and Walter Blattler and each of them singly, as true and lawful attorneys, with full power to them and each of them singly, to sign for us in our names in the capacities indicated below, all additional amendments to this registration statement, and generally to do all things in our names and on our behalf in such capacities to enable ImmunoGen, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all applicable requirements of the Securities and Exchange Commission. Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated. Title: Date: /s/ Mitchel Sayare Chairman of the Board January 4, 2001 - --------------------- of Directors and Mitchel Sayare Chief Executive Officer (principal executive officer) /s/ Walter A. Blattler - --------------------- Executive Vice President, January 4, 2001 Walter A. Blattler Science and Technology, Treasurer and Director /s/ Virginia A. Lavery Senior Corporate Controller January 4, 2001 - --------------------- (principal accounting officer) Virginia A. Lavery /s/ David W. Carter Director January 4, 2001 - --------------------- David W. Carter /s/ Michael R. Eisenson Director January 4, 2001 - --------------------- Michael R. Eisenson /s/ Stuart F. Feiner Director January 4, 2001 - --------------------- Stuart F. Feiner /s/ Mark S. Skaletsky Director January 4, 2001 - --------------------- Mark S. Skaletsky 6 IMMUNOGEN, INC. EXHIBIT INDEX EXHIBIT NO. DESCRIPTION - -------------------------- (4.1) Form of Common Stock Certificate (previously filed as Exhibit 4.2 to the Registrant's Registration Statement on Form S-1, Registration No. 33-31219, as amended, and incorporated herein by reference) (4.2) Restated Articles of Organization of the Registrant (previously filed as Exhibit 3.1 to the Registrant's Registration Statement on Form S-1, Registration No. 33-38883, as amended, and incorporated herein by reference) (4.3) By-Laws, as amended, of the Registrant (previously filed as Exhibit 3.2 to the Registrant's annual report on Form 10-K for the fiscal year ended June 30, 1990, and incorporated herein by reference) (5) Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., with respect to the legality of the shares being registered (23.1) Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in opinion of counsel filed as Exhibit 5) (23.2) Consent of PricewaterhouseCoopers (24) Power of Attorney to file future amendments (included on the signature page of this Registration Statement) (99) ImmunoGen, Inc. Restated Stock Option Plan (as amended) 7