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): June 20, 2008

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):

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

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

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

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

ITEM 1.01.  ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT

On June 20, 2008, pursuant to a securities purchase agreement (the “Purchase Agreement”) between ImmunoGen, Inc. (the “Company”) and Ziff Asset Management, L.P. (“Ziff”), the Company issued and sold 7,812,500 shares of its common stock at a purchase price of $3.20 per share to Ziff (the “Offering”).  The net proceeds to the Company are expected to be approximately $24.7 million after deducting estimated expenses associated with the Offering.

The shares of common stock offered by the Company in the Offering were registered under the Company’s existing shelf registration statement on Form S-3 (File No. 333-144488), which was filed with the Securities and Exchange Commission on July 11, 2007 and declared effective by the Securities and Exchange Commission on August 13, 2007.  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 in the Offering is attached as Exhibit 5.1 hereto.

In addition, on June 20, 2008, the Company entered into a registration rights agreement (the “Registration Rights Agreement”) with Ziff pursuant to which the Company agreed to file a registration statement with the Securities and Exchange Commission within 45 days after the closing of the Offering to register the resale of the 7,812,500 shares of the Company’s common stock issued in the Offering and to have such registration statement declared effective by the Securities and Exchange Commission within 90 days of the closing of the Offering.

A copy of the Purchase Agreement, the Registration Rights Agreement and the related press release of the Company, dated June 23, 2008, are filed herewith as Exhibits 10.1, 10.2 and 99.1, respectively, and are incorporated herein by reference.  The foregoing description of the Offering by the Company and the documentation related thereto is qualified in its entirety by reference to such Exhibits.

ITEM 9.01.  FINANCIAL STATEMENTS AND EXHIBITS

(d) The following exhibits are being filed herewith:

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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.

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EXHIBIT INDEX

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EXHIBIT 5.1

June 20, 2008

ImmunoGen, Inc.

830 Winter Street

Waltham, MA 02451

Ladies and Gentlemen:

This opinion is furnished to you in connection with a Prospectus Supplement, dated June 20, 2008, to a Prospectus dated August 13, 2007 (the “Prospectus and Prospectus Supplement”), filed pursuant to a Registration Statement on Form S-3, Registration No. 333-144488 (the “Registration Statement”) filed by ImmunoGen, Inc., a Massachusetts corporation (the “Company”), with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), with respect to an aggregate of 7,812,500 shares (the “Shares”) of its common stock, $0.01 par value per share (the “Common Stock”). The Shares are to be sold pursuant to a Securities Purchase Agreement (the “Purchase Agreement”) dated June 20, 2008 between the Company and the purchaser named therein, which Purchase Agreement will be filed as an exhibit to a Current Report on Form 8-K and incorporated by reference into the Registration Statement.

In connection with this opinion, we have examined the Company’s articles of organization and bylaws, both as amended and currently in effect; the minutes of all pertinent meetings of directors of the Company relating to the Registration Statement, the Prospectus and Prospectus Supplement and the transactions contemplated thereby; such other records of the corporate proceedings of the Company and certificates of the Company’s officers as we have deemed relevant for the purposes of rendering the opinions in this letter; the Registration Statement and the exhibits thereto filed with the Commission; and the Prospectus and Prospectus Supplement.

In our examination, we have assumed the genuineness of all signatures, the legal capacity of natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as certified, photostatic or facsimile copies and the authenticity of the originals of such copies.

Members of our firm are admitted to the Bar of the Commonwealth of Massachusetts, and we do not express any opinion as to the laws of any other jurisdiction other than the United States Federal Laws and the reported judicial decisions interpreting those laws. To the extent that any applicable document is stated to be governed by the laws of another jurisdiction, we have assumed for purposes of this opinion that the laws of such jurisdiction are identical to the state laws of the Commonwealth of Massachusetts. No opinion is expressed herein with respect to the qualification of the Shares under the securities or blue sky laws of any state or any foreign jurisdiction. This opinion is limited to the laws, including the rules and regulations thereunder, as in effect on the date hereof.

Based upon the foregoing, and subject to the limitations set forth below, we are of the opinion that the Shares, when issued by the Company and delivered by the Company against payment therefor as contemplated by the Purchase Agreement, will be duly and validly issued, fully paid and non-assessable shares of the Common Stock.

Please note that we are opining only as to the matters expressly set forth herein, and no opinion should be inferred as to any other matters.  This opinion is based upon currently existing statutes, rules, regulations and judicial decisions, and we disclaim any obligation to advise you of any change in any of these sources of law or subsequent legal or factual developments which might affect any matters or opinions set forth herein.

We hereby consent to the filing of this opinion with the Commission as an exhibit to a Current Report on Form 8-K and the Registration Statement in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of this Firm’s name therein and in the Prospectus and Prospectus Supplement under the caption “Legal Matters.”  In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

Exhibit 10.1

EXECUTION COPY

SECURITIES PURCHASE AGREEMENT

This Securities Purchase Agreement (this “Agreement”) is dated as of June 20, 2008, between ImmunoGen, Inc., a Massachusetts corporation (the “Company”), and Ziff Asset Management, L.P., a Delaware limited partnership (the “Purchaser”).

WHEREAS, subject to the terms and conditions set forth in this Agreement and pursuant to an effective registration statement under the Securities Act (as defined below), the Company desires to issue and sell to the Purchaser, and the Purchaser desires to purchase from the Company, securities of the Company as more fully described in this Agreement; and

WHEREAS, the parties hereto are concurrently entering into a registration rights agreement in the form of Exhibit A hereto (the “Registration Rights Agreement”) pursuant to which the Company shall register the Shares (as defined below) for resale by the Purchaser upon the terms and subject to the conditions set forth therein.

NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in this Agreement, and for other good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the Company and the Purchaser agree as follows:

ARTICLE I.

DEFINITIONS

1.1           Definitions.  In addition to the terms defined elsewhere in this Agreement, for all purposes of this Agreement, the following terms have the meanings set forth in this Section 1.1:

“Action” shall have the meaning ascribed to such term in Section 3.1(j).

“Affiliate” means any Person that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control with a Person as such terms are used in and construed under Rule 405 under the Securities Act.

“Board of Directors” means the board of directors of the Company.

“Business Day” means any day except any Saturday, any Sunday, any day which is a federal legal holiday in the United States or any day on which banking institutions in the State of New York are authorized or required by law or other governmental action to close.

“Closing” means the closing of the purchase and sale of the Shares pursuant to Section 2.1.

“Closing Date” means the date hereof.

“Commission” means the United States Securities and Exchange Commission or any other federal agency at the time administering the Securities Act.

“Common Stock” means the common stock of the Company, par value $0.01 per

share, any class of common stock of the Company hereafter created, and any other class of securities into which such Common Stock may hereafter be reclassified or changed into.

“Common Stock Equivalents” means any securities of the Company or the Subsidiaries which would entitle the holder thereof to acquire at any time Common Stock, including, without limitation, any debt, preferred stock, rights, options, warrants or other instrument that is at any time convertible into or exercisable or exchangeable for, or otherwise entitles the holder thereof to receive, Common Stock.

“Company Counsel” means Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., with offices located at One Financial Center, Boston, MA 02111.

“Disclosure Schedules” means the Disclosure Schedules of the Company delivered concurrently herewith.

“Evaluation Date” shall have the meaning ascribed to such term in Section 3.1(r).

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“FDA” shall have the meaning ascribed to such term in Section 3.1(gg).

“FDCA” shall have the meaning ascribed to such term in Section 3.1(gg).

“GAAP” shall have the meaning ascribed to such term in Section 3.1(h).

“Indebtedness” means (a) any liabilities for borrowed money or amounts owed in excess of $50,000 (other than trade accounts payable incurred in the ordinary course of business), (b) all guaranties, endorsements and other contingent obligations in respect of indebtedness of others, whether or not the same are or should be reflected in the Company’s balance sheet (or the notes thereto), except guaranties by endorsement of negotiable instruments for deposit or collection or similar transactions in the ordinary course of business; and (c) the present value of any lease payments in excess of $50,000 due under leases required to be capitalized in accordance with GAAP.

“Intellectual Property Rights” shall have the meaning ascribed to such term in Section 3.1(o).

“Lien” means any lien, claim, pledge, charge, security interest, encumbrance, right of first refusal, preemptive right or other restriction.

“Lock-up Agreements” shall have the meaning ascribed to such term in Section 2.2(a)(iii).

“Losses” shall have the meaning ascribed to such term in Section 4.7.

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“Material Adverse Effect” shall have the meaning ascribed to such term in Section 3.1(b).

“Material Permits” shall have the meaning ascribed to such term in Section 3.1(m).

“Person” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“Pharmaceutical Product” shall have the meaning ascribed to such term in Section 3.1(gg).

“Prospectus” means the final prospectus filed as a part of the Registration Statement.

“Prospectus Supplement” means the supplement to the Prospectus complying with Rule 424(b) of the Securities Act that is filed with the Commission with respect to the transactions contemplated hereby.

“Purchase Price” means $25,000,000.

“Purchaser Party” shall have the meaning ascribed to such term in Section 4.7.

“Registration Rights Agreement” shall have the meaning set forth in the recitals of this Agreement.

“Registration Statement” means the effective registration statement with Commission file No. 333-144488 which registers the sale of the Shares to the Purchaser.

“Required Approvals” shall have the meaning ascribed to such term in Section 3.1(e).

“Rule 144” means Rule 144 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as such Rule.

“SEC Reports” shall have the meaning ascribed to such term in Section 3.1(h).

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“Shares” means 7,812,500 shares of Common Stock to be issued to the Purchaser pursuant to this Agreement.

“Short Sales” means all “short sales” as defined in Rule 200 of Regulation SHO under the Exchange Act and all types of direct and indirect stock pledges, forward sale

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contracts, options, puts, calls, short sales, swaps and similar arrangements (including on a total return basis), and sales and other transactions through non-U.S. broker-dealers or foreign regulated brokers.

“Subsidiary” means any subsidiary of the Company as set forth on Schedule 3.1(a) , which shall include any direct or indirect subsidiary of the Company formed or acquired after the date hereof.

“Trading Day” means a day on which the Nasdaq Global Market is open for trading.

“Trading Market” means any of the following markets or exchanges on which the Common Stock is then listed or quoted for trading on the date in question: the American Stock Exchange, the Nasdaq Capital Market, the Nasdaq Global Market, the Nasdaq Global Select Market, the New York Stock Exchange or the OTC Bulletin Board.

“Transaction Documents” means this Agreement, the Registration Rights Agreement, the Lock-up Agreements and any other documents or agreements executed in connection with the transactions contemplated hereunder.

“Transfer Agent” means Mellon Investor Service LLC, the current transfer agent of the Company, with a mailing address of 111 Founders Plaza, Suite 1100, East Hartford, CT 06108 and a facsimile number of (860) 528-6472 and any successor transfer agent of the Company.

ARTICLE II.
PURCHASE AND SALE

2.1           Closing.  On the Closing Date, upon the terms and subject to the conditions set forth herein, substantially concurrent with the execution and delivery of this Agreement by the parties hereto, the Company agrees to sell, and the Purchaser agrees to purchase the Shares.  The Purchaser shall deliver to the Company, via wire transfer, immediately available funds equal to the Purchase Price and the Company shall deliver to the Purchaser the Shares, and the Company and the Purchaser shall deliver the other items set forth in Section 2.2 deliverable at the Closing.  Upon satisfaction of the covenants and conditions set forth in Sections 2.2 and 2.3, the Closing shall occur at the offices of Fried, Frank, Harris, Shriver & Jacobson LLP, One New York Plaza, New York, NY 10004 or such other location as the parties shall mutually agree.

2.2           Closing Deliveries.

(a)           On or prior to the Closing Date, the Company shall deliver or cause to be delivered to the Purchaser the following:

(i)            this Agreement duly executed by the Company;

(ii)           the Registration Rights Agreement duly executed by the Company;

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(iii)          lock-up agreements in substantially the form attached hereto as Exhibit B duly executed by the Company and each of the Persons listed in Exhibit C (collectively, the “Lock-up Agreements”)

(iv)          a legal opinion of Company Counsel, substantially in the form of Exhibit D attached hereto;

(v)           a legal opinion of the Company’s General Counsel, substantially in the form of Exhibit E attached hereto;

(vi)          a copy of the irrevocable instructions to the Company’s transfer agent instructing the transfer agent to deliver, via the Depository Trust Company Deposit Withdrawal Agent Commission System, the Shares to the Purchaser’s accounts, as directed by the Purchaser; and

(vii)         evidence of the approval for listing of the Shares on the Nasdaq Global Market.

(b)           On or prior to the Closing Date, the Purchaser shall deliver or cause to be delivered to the Company the following:

(i)            this Agreement duly executed by the Purchaser;

(ii)           the Registration Rights Agreement duly executed by the Purchaser; and

(iii)          the Purchase Price by wire transfer to the account specified in writing by the Company to the Purchaser at least three Business days prior to the Closing Date.

2.3           Closing Conditions.

(a)           The obligations of the Company hereunder in connection with the Closing are subject to the following conditions being met:

(i)            the accuracy in all material respects on the Closing Date of the representations and warranties of the Purchaser contained herein;

(ii)           all obligations, covenants and agreements of the Purchaser required to be performed at or prior to the Closing Date shall have been performed; and

(iii)          the delivery by the Purchaser of the items set forth in Section 2.2(b) of this Agreement.

(b)           The obligations of the Purchaser hereunder in connection with the Closing are subject to the following conditions being met:

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(i)            the accuracy in all material respects on the Closing Date of the representations and warranties of the Company contained herein;

(ii)           all obligations, covenants and agreements of the Company required to be performed at or prior to the Closing Date shall have been performed; and

(iii)          the delivery by the Company of the items set forth in Section 2.2(a) of this Agreement.

ARTICLE III.
REPRESENTATIONS AND WARRANTIES

3.1           Representations and Warranties of the Company.  Except as set forth in the Disclosure Schedules, which Disclosure Schedules shall be deemed a part hereof and shall qualify any representation or otherwise made herein to the extent of the disclosure contained in the corresponding section of the Disclosure Schedules, the Company hereby makes the following representations and warranties to the Purchaser as of the date of this Agreement, except for any representations and warranties made as of other dates set forth in such representations and warranties:

(a)           Subsidiaries.  All of the direct and indirect Subsidiaries of the Company are set forth on Schedule 3.1(a).  The Company owns, directly or indirectly, all of the capital stock or other equity interests of each Subsidiary free and clear of any Liens, and all of the issued and outstanding shares of capital stock of each Subsidiary are validly issued and are fully paid, non-assessable and free of preemptive and similar rights to subscribe for or purchase securities created by the certificate of incorporation, bylaws or other organizational or charter documents of such Subsidiaries or any agreement to which the Company or any Subsidiary is a party.

(b)           Organization and Qualification.  The Company and each of the Subsidiaries is an entity duly incorporated or otherwise organized, validly existing and in good standing under the laws of the jurisdiction of its incorporation or organization (as applicable), with the requisite power and authority to own and use its properties and assets and to carry on its business as currently conducted.  Neither the Company nor any Subsidiary is in violation or default of any of the provisions of its respective certificate or articles of incorporation, bylaws or other organizational or charter documents.  The Company and each of the Subsidiaries is duly qualified to conduct business and is in good standing as a foreign corporation or other entity in each jurisdiction in which the nature of the business conducted or property owned by it makes such qualification necessary, except where the failure to be so qualified or in good standing, as the case may be, could not, individually or in the aggregate, have or reasonably be expected to result in (i) a material adverse effect on the legality, validity or enforceability of any Transaction Document, (ii) a material adverse effect on the results of operations, assets, business, prospects or condition (financial or otherwise) of the Company and the Subsidiaries, taken as a whole, or (iii) a material adverse effect on the Company’s ability to perform in any material respect on a timely basis its obligations under any Transaction Document

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(any of (i), (ii) or (iii), a “Material Adverse Effect”) and no Action has been instituted in any such jurisdiction revoking, limiting or curtailing or seeking to revoke, limit or curtail such power and authority or qualification.  The Company has made available to the Purchaser, prior to the date of this Agreement, true and complete copies of the Amended and Restated Articles of Organization of the Company and the Amended and Restated Bylaws of the Company, in each case as in effect on the date of this Agreement.

(c)           Authorization; Enforcement.  The Company has the requisite corporate power and authority to enter into and to consummate the transactions contemplated by each of the Transaction Documents and otherwise to carry out its obligations hereunder and thereunder.  The execution and delivery of each of the Transaction Documents by the Company and the consummation by it of the transactions contemplated hereby and thereby have been duly authorized by all necessary action on the part of the Company and no further action is required by the Company, the Board of Directors or the Company’s stockholders in connection therewith other than in connection with the Required Approvals.  Each Transaction Document has been (or upon delivery will have been) duly executed by the Company and, when delivered in accordance with the terms hereof and thereof, will constitute the valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except (i) as limited by general equitable principles and applicable bankruptcy, insolvency, reorganization, moratorium and other laws of general application affecting enforcement of creditors’ rights generally, (ii) as limited by laws relating to the availability of specific performance, injunctive relief or other equitable remedies and (iii) insofar as indemnification and contribution provisions may be limited by applicable law.

(d)           No Conflicts.  The execution, delivery and performance of the Transaction Documents by the Company, the issuance and sale of the Shares and the consummation by the Company of the other transactions contemplated hereby and thereby do not and will not (i) conflict with or violate any provision of the Company’s or any Subsidiary’s certificate or articles of incorporation, bylaws or other organizational or charter documents, or (ii) conflict with, or constitute a default (or an event that with notice or lapse of time or both would become a default) under, result in the creation of any Lien upon any of the properties or assets of the Company or any Subsidiary, or give to others any rights of termination, amendment, acceleration or cancellation (with or without notice, lapse of time or both) of, any note, bond, mortgage, indenture, deed of trust, license, lease, agreement, credit facility, debt (or other instrument evidencing a Company or Subsidiary debt or otherwise) or other instrument or understanding to which the Company or any Subsidiary is a party or by which any property or asset of the Company or any Subsidiary is bound or affected, or (iii) subject to obtaining the Required Approvals, conflict with or result in a violation of any law, rule, regulation, order, judgment, injunction, decree or other restriction of any court or governmental authority to which the Company or a Subsidiary is subject (including federal and state securities laws and regulations, and the regulations of any self-regulatory organization to which the Company or its Subsidiaries are subject), or by which any property or asset of the Company or a Subsidiary is bound or affected; except in the case of each of clauses (ii) and (iii), such as could not, individually or in the aggregate, have or reasonably be

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expected to result in a Material Adverse Effect.

(e)           Filings, Consents and Approvals.  The Company is not required to obtain any consent, waiver, authorization or order of, give any notice to, or make any filing or registration with, any court or other federal, state, local or other governmental authority or any other Person in connection with the execution, delivery and performance by the Company of the Transaction Documents, other than prior notification to NASDAQ of the issuance of the Shares, which the Company has given in a timely manner, and (i) the filing with the Commission of the Prospectus Supplement and (ii) such filings as are required to be made under applicable state securities laws (the filings required in clauses (i) and (ii), collectively, the “Required Approvals”).  Except for the Required Approvals, all consents, authorizations, orders, filings and registrations which the Company is required to obtain, and all notices, filings and registrations it is required to make, in connection with the transactions contemplated by each of the Transaction Documents have been obtained or effected or been timely made, on or prior to the Closing Date.

(f)            Issuance of the Shares; Registration.  The Shares are duly authorized and, when issued and paid for in accordance with the applicable Transaction Documents, will be duly and validly issued, fully paid and nonassessable, free and clear of all Liens (other than Liens created by the Purchaser).  The Company has prepared and filed the Registration Statement in conformity in all material respects with the requirements of the Securities Act, which became effective on August 13, 2007 (the “Effective Date”), including the Prospectus, and such amendments and supplements thereto as may have been required to the date of this Agreement.  The Registration Statement is effective under the Securities Act and no stop order preventing or suspending the effectiveness of the Registration Statement or suspending or preventing the use of the Prospectus has been issued by the Commission and no proceedings for that purpose have been instituted or, to the knowledge of the Company, are threatened by the Commission.  The Shares (i) have been registered pursuant to the Registration Statement, (ii) are being issued pursuant to the Registration Statement and (iii) are not “restricted securities” within the meaning of Rule 144.  Any certificate representing the Shares shall not contain any legend or other limitation on resale.  The Company proposes to file the Prospectus Supplement with the SEC pursuant to Rule 424(b).  At the time the Registration Statement and any amendments thereto became effective, at the date of this Agreement and at the Closing Date, the Registration Statement and any amendments thereto conformed and will conform in all material respects to the requirements of the Securities Act and did not and will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading; and the Prospectus and any amendments or supplements thereto, at the time the Prospectus or any amendment or supplement thereto was issued and at the Closing Date, conformed and will conform in all material respects to the requirements of the Securities Act and did not and will not contain an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

(g)           Capitalization.  The capitalization of the Company is as set forth on

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Schedule 3.1(g).  The Company has not issued any capital stock since its most recently filed periodic report under the Exchange Act, other than pursuant to the exercise of employee stock options, and the award of shares of Common Stock, under the Company’s stock incentive plans that were outstanding as of the date of the most recently filed periodic report under the Exchange Act and are reflected on Schedule 3.1(g).  No Person has any right of first refusal, preemptive right, right of participation, or any similar right to participate in the transactions contemplated by the Transaction Documents.  Except as set forth on Schedule 3.1(g), there are no outstanding options, warrants, scrip rights to subscribe to, calls or commitments of any character whatsoever relating to, or securities, rights or obligations convertible into or exercisable or exchangeable for, or giving any Person any right to subscribe for or acquire, any shares of Common Stock or Common Stock Equivalents, or contracts, commitments, understandings or arrangements by which the Company or any Subsidiary is or may become bound to issue additional shares of Common Stock or Common Stock Equivalents.  The issuance and sale of the Shares will not obligate the Company to issue shares of Common Stock or other securities to any Person and will not result in a right of any holder of Company securities to adjust the exercise, conversion, exchange or reset price under any of such securities.  All of the outstanding shares of capital stock of the Company are validly issued, fully paid and nonassessable, have been issued in compliance with all federal and state securities laws, and none of such outstanding shares was issued in violation of any preemptive rights or similar rights to subscribe for or purchase securities.  No further approval or authorization of any stockholder, the Board of Directors or others is required for the issuance and sale of the Shares.  There are no stockholders agreements, voting agreements, registration rights agreements or other similar agreements with respect to the Company’s capital stock to which the Company is a party or, to the knowledge of the Company, between or among any of the Company’s stockholders.

(h)           SEC Reports; Financial Statements.  The Company has filed or furnished all reports, schedules, forms, statements and other documents required to be filed or furnished by the Company under the Securities Act and the Exchange Act, including pursuant to Section 13(a) or 15(d) thereof, for the two years preceding the date hereof (the foregoing materials, including the exhibits thereto and documents incorporated by reference therein, together with the Prospectus and the Prospectus Supplement, being collectively referred to herein as the “SEC Reports”) on a timely basis.  As of their respective dates, the SEC Reports complied in all material respects with the requirements of the Securities Act and the Exchange Act, as applicable, and none of the SEC Reports, when filed or furnished, contained any untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.  There are no outstanding comments from the Commission with respect to any SEC Report.  The Company does not have pending before the Commission any request for confidential treatment of information.  The financial statements of the Company included in the SEC Reports comply in all material respects with applicable accounting requirements and the rules and regulations of the Commission with respect thereto as in effect at the time of filing.  Such financial statements have been prepared in

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accordance with United States generally accepted accounting principles applied on a consistent basis during the periods involved (“GAAP”), except as may be otherwise specified in such financial statements or the notes thereto and except that unaudited financial statements may not contain all footnotes required by GAAP, and fairly present in all material respects the financial position of the Company and its consolidated Subsidiaries as of and for the dates thereof and the consolidated results of their operations and cash flows for the periods then ended, subject, in the case of unaudited statements, to normal, immaterial, year-end audit adjustments.

(i)            Material Changes; Undisclosed Events, Liabilities or Developments.

(i)            Since June 30, 2007, there has been no event, occurrence or development that could, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect.

(ii)           Except as set forth in the latest audited consolidated balance sheet included within the SEC Reports filed prior to the date of this Agreement or on Schedule 3.1(i)(ii), the Company and the Subsidiaries do not have any obligations or liabilities (whether absolute, contingent, accrued or otherwise) other than trade payables and accrued expenses incurred in the ordinary course of business consistent with past practice since the date of the latest audited consolidated balance sheet included within the SEC Reports filed prior to the date of this Agreement, that are material to the Company and its Subsidiaries taken as a whole.

(iii)          Since the date of the latest audited consolidated balance sheet included within the SEC Reports filed prior to the date of this Agreement, (A) the Company has not altered its method of accounting in any material respect, (B) the Company has not declared or made any dividend or distribution of cash or other property to its stockholders or purchased, redeemed or made any agreements to purchase or redeem any shares of its capital stock and (C) the Company has not issued any Common Stock or Common Stock Equivalents to any officer, director or any Affiliate of the Company, except pursuant to existing Company stock incentive plans.

(iv)          Except for the issuance of the Shares contemplated by this Agreement, no event, liability or development has occurred or exists with respect to the Company or its Subsidiaries or their respective business, properties, operations or financial condition, that would be required to be disclosed by the Company under applicable securities laws and that has not been so disclosed.

(j)            Litigation.  There is no action, suit, inquiry, notice of violation, proceeding or investigation pending or, to the knowledge of the Company, threatened against or affecting the Company, any Subsidiary or any of their respective properties before or by any court, arbitrator, governmental or administrative agency or regulatory authority (federal, state, county, local or foreign) (collectively, an “Action”) which (i) adversely affects or challenges the legality, validity or enforceability of any of the Transaction

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Documents or the Shares or (ii) could, individually or in the aggregate, if there were an unfavorable decision, have or reasonably be expected to result in a Material Adverse Effect. Neither the Company nor any Subsidiary, nor any current director or officer thereof, is or has been the subject of any Action involving a claim of violation of or liability under federal or state securities laws or a claim of breach of fiduciary duty.  There has not been, and to the knowledge of the Company, there is not pending or contemplated, any investigation by the Commission involving the Company or any current director or officer of the Company.  The Commission has not issued any stop order or other order suspending the effectiveness of any registration statement filed by the Company or any Subsidiary under the Exchange Act or the Securities Act.

(k)           Labor Relations.  No labor dispute exists or, to the knowledge of the Company, is imminent with respect to any of the employees of the Company which, individually or in the aggregate, has had or could reasonably be expected to result in a Material Adverse Effect.  None of the Company’s or its Subsidiaries’ employees is a member of a union that relates to such employee’s relationship with the Company or such Subsidiary, and neither the Company nor any of its Subsidiaries is a party to a collective bargaining agreement, and the Company and its Subsidiaries believe that their relationships with their employees are good.  No executive officer, to the knowledge of the Company, is, or is now expected to be, in violation of any material term of any employment contract, confidentiality, disclosure or proprietary information agreement or non-competition agreement, or any other contract or agreement or any restrictive covenant in favor of any third party, and the continued employment of each such executive officer does not subject the Company or any of its Subsidiaries to any liability with respect to any of the foregoing matters. The Company and its Subsidiaries are in compliance with all U.S. federal, state, local and foreign laws and regulations relating to employment and employment practices, terms and conditions of employment and wages and hours, except where the failure to be in compliance could not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect.

(l)            Compliance.  Neither the Company nor any Subsidiary (i) is in default under or in violation of (and no event has occurred that has not been waived that, with notice or lapse of time or both, would result in a default by the Company or any Subsidiary under), nor has the Company or any Subsidiary received notice of a claim that it is in default under or that it is in violation of, any indenture, loan or credit agreement or any other agreement or instrument to which it is a party or by which it or any of its properties is bound (whether or not such default or violation has been waived), (ii) is in violation of any order of any court, arbitrator or governmental body, or (iii) is or has been since January 1, 2006, in violation of any statute, rule or regulation of any governmental authority, including without limitation all foreign, federal, state and local laws applicable to its business and all such laws that affect the environment, except in each case as could not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect.

(m)          Regulatory Permits.  The Company and the Subsidiaries possess all certificates, authorizations and permits issued by the appropriate federal, state, local or

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foreign regulatory authorities necessary to conduct their respective businesses as described in the SEC Reports (collectively, the “Material Permits”), except where the failure to possess such permits could not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect.  Neither the Company nor any Subsidiary has received any notice of proceedings relating to the revocation or modification of any Material Permit.

(n)           Title to Assets.  The Company and the Subsidiaries have good and marketable title in fee simple to all real property owned by them and good and marketable title in all personal property owned by them that is material to the business of the Company and the Subsidiaries, in each case free and clear of all Liens, except for (i) Liens that do not materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the Company and the Subsidiaries, (ii) Liens for the payment of federal, state or other taxes, the payment of which is neither delinquent nor subject to penalties, and (iii) Liens that could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.  Any real property and facilities held under lease by the Company and the Subsidiaries are held by them under valid, subsisting and enforceable leases with which the Company and the Subsidiaries are in compliance.

(o)           Patents and Trademarks.  The Company and the Subsidiaries have, or have rights to use, all patents, patent applications, trademarks, trademark applications, service marks, trade names, trade secrets, inventions, copyrights, licenses and other intellectual property rights and similar rights necessary or material for use in connection with their respective businesses as described in the SEC Reports and which the failure to so have could, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect (collectively, the “Intellectual Property Rights”).  Neither the Company nor any Subsidiary has received a notice (written or otherwise) that any of the Intellectual Property Rights used by the Company or any Subsidiary violates or infringes upon the rights of any Person.  To the knowledge of the Company, all such Intellectual Property Rights are enforceable and there is no existing infringement by another Person of any of the Intellectual Property Rights.  With respect to intellectual property owned by the Company or its Subsidiaries, the Company and its Subsidiaries have taken reasonable security measures, except where disclosure has been required pursuant to applicable rules and regulations of the Patent and Trademark Office or corresponding international authorities, to protect the secrecy, confidentiality and value of all of their intellectual properties, except where failure to do so could not, individually or in the aggregate, have or reasonably be expected to have a Material Adverse Effect.

(p)           Insurance.  The Company and the Subsidiaries are insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are customary in the businesses in which the Company and the Subsidiaries are engaged, including, but not limited to, directors and officers insurance coverage.  Neither the Company nor any Subsidiary has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business without a

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significant increase in cost.

(q)           Transactions with Affiliates and Employees.  Except as set forth in the SEC Reports, none of the officers, directors or employees of the Company is presently a party to any transaction with the Company or any Subsidiary (other than for services as employees, officers and directors), including any contract, agreement or other arrangement providing for the furnishing of services to or by, providing for rental of real or personal property to or from, or otherwise requiring payments to or from any officer, director or such employee or, to the knowledge of the Company, any entity in which any officer, director, or any such employee has a substantial interest or is an officer, director, trustee or partner, in each case in excess of $120,000 other than for (i) payment of salary or consulting fees for services rendered, (ii) reimbursement for expenses incurred on behalf of the Company and (iii) other employee benefits, including stock option agreements under any stock option plan of the Company.

(r)            Sarbanes-Oxley; Internal Accounting Controls.  The Company is in material compliance with all provisions of the Sarbanes-Oxley Act of 2002 (including all rules and regulations promulgated thereunder) which are applicable to it as of the Closing Date.  The Company and the Subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset accountability, (iii) access to assets is permitted only in accordance with management’s general or specific authorization, and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.  The Company has established disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the Company and designed such disclosure controls and procedures to ensure that information required to be disclosed by the Company in the reports it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the Commission’s rules and forms.  The Company’s certifying officers have evaluated the effectiveness of the Company’s disclosure controls and procedures as of the end of the period covered by the Company’s most recently filed periodic report under the Exchange Act (such date, the “Evaluation Date”).  The Company presented in its most recently filed periodic report under the Exchange Act the conclusions of the certifying officers about the effectiveness of the disclosure controls and procedures based on their evaluations as of the Evaluation Date.  Since the Evaluation Date, there have been no changes in the Company’s internal control over financial reporting (as such term is defined in the Exchange Act) that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting.

(s)           Certain Fees.  No brokerage or finder’s fees or commissions are or will be payable by the Company to any broker, financial advisor or consultant, finder, placement agent, investment banker, bank or other Person with respect to the transactions contemplated by the Transaction Documents.  The Purchaser shall not have any

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obligation with respect to any fees or with respect to any claims made by or on behalf of other Persons for fees of a type contemplated in this Section that may be due in connection with the transactions contemplated by the Transaction Documents.

(t)            Investment Company.  The Company is not, and is not an Affiliate of, and immediately after receipt of payment for the Shares, will not be or be an Affiliate of, an “investment company” within the meaning of the Investment Company Act of 1940, as amended. The Company shall conduct its business in a manner so that it will not become subject to the Investment Company Act of 1940, as amended.

(u)           Registration Rights.  No Person has any right to cause the Company to effect the registration under the Securities Act of any securities of the Company, other than the Purchaser pursuant to the Registration Rights Agreement.

(v)           Listing and Maintenance Requirements.  The Common Stock is registered pursuant to Section 12(b) of the Exchange Act, and the Company has taken no action designed to, or which to its knowledge is likely to have the effect of, terminating the registration of the Common Stock under the Exchange Act nor has the Company received any notification that the Commission is contemplating terminating such registration.  The Company has not, in the 12 months preceding the date hereof, received notice from any Trading Market on which the Common Stock is or has been listed or quoted to the effect that the Company is not in compliance with the listing or maintenance requirements of such Trading Market.  The Company is, and has no reason to believe that it will not in the foreseeable future continue to be, in compliance in all material respects with all such listing and maintenance requirements.

(w)          Application of Takeover Protections.  The Company and the Board of Directors have taken all necessary action, if any, in order to render inapplicable any control share acquisition, business combination or other similar anti-takeover provision under the Company’s certificate of incorporation (or similar charter documents) or the laws of its state of incorporation that is or could become applicable to the Purchaser as a result of the Purchaser and the Company fulfilling their obligations or exercising their rights under the Transaction Documents, including without limitation as a result of the Company’s issuance of the Shares and the Purchaser’s ownership of the Shares.  The Company does not have any “poison pill” or similar arrangements.

(x)            Disclosure.  Except with respect to the material terms and conditions of the transactions contemplated by the Transaction Documents, the Company confirms that neither it nor, to the Company’s knowledge, any other Person acting on its behalf has provided the Purchaser or its agents or counsel with any information that it believes constitutes or might constitute material, non-public information which is not otherwise disclosed in the Prospectus Supplement.  The Company understands and confirms that the Purchaser will rely on the foregoing representation in effecting transactions in securities of the Company.  All information or document furnished by or on behalf of the Company to the Purchaser regarding the Company, its business and the transactions contemplated hereby, including the Disclosure Schedules to this Agreement, is true and correct and does not contain any untrue statement of a material fact or omit to state any

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material fact necessary in order to make the statements made therein, in light of the circumstances under which they were made, not misleading. The press releases disseminated by the Company during the twelve months preceding the date of this Agreement taken as a whole do not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made and when made, not misleading.  The Company acknowledges and agrees that the Purchaser does not make or has not made any representations or warranties with respect to the transactions contemplated hereby other than those specifically set forth in Section 3.2 hereof.

(y)           No Integrated Offering.  Neither the Company, nor any of its Affiliates, nor any Person acting on its or their behalf has, directly or indirectly, made any offers or sales of any security or solicited any offers to buy any security, under circumstances that would cause this offering of the Shares to be integrated with prior offerings by the Company for purposes of any applicable shareholder approval provisions of any Trading Market on which any of the securities of the Company are listed or designated or otherwise.

(z)            Solvency.  Based on the consolidated financial condition of the Company as of the Closing Date, after giving effect to the receipt by the Company of the proceeds from the sale of the Shares hereunder, (i) the fair saleable value of the Company’s assets exceeds the amount that will be required to be paid on or in respect of the Company’s existing debts and other liabilities (including known contingent liabilities) as they mature, (ii) the Company’s assets do not constitute unreasonably small capital to carry on its business as now conducted and as proposed to be conducted including its capital needs taking into account the particular capital requirements of the business conducted by the Company, and projected capital requirements and capital availability thereof, and (iii) the current cash flow of the Company, together with the proceeds the Company would receive, were it to liquidate all of its assets, after taking into account all anticipated uses of the cash, would be sufficient to pay all amounts on or in respect of its liabilities when such amounts are required to be paid.  The Company does not intend to incur debts beyond its ability to pay such debts as they mature (taking into account the timing and amounts of cash to be payable on or in respect of its debt).  The Company has no knowledge of any facts or circumstances which lead it to believe that it will file for reorganization or liquidation under the bankruptcy or reorganization laws of any jurisdiction within one year from the Closing Date.  Neither the Company nor any Subsidiary is in default with respect to any Indebtedness.

(aa)         Tax Status.  Except for matters that could not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect, the Company and each Subsidiary has filed all necessary federal, state and foreign income and franchise tax returns and has paid or accrued all taxes shown as due thereon through the date hereof, and the Company has no knowledge of a tax deficiency which has been asserted or threatened against the Company or any Subsidiary.

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(bb)         Foreign Corrupt Practices.  Neither the Company, nor to the knowledge of the Company, any agent or other person acting on behalf of the Company, has (i) directly or indirectly, used any funds for unlawful contributions, gifts, entertainment or other unlawful expenses related to foreign or domestic political activity, (ii) made any unlawful payment to foreign or domestic government officials or employees or to any foreign or domestic political parties or campaigns from corporate funds, (iii) failed to disclose fully any contribution made by the Company (or made by any person acting on its behalf of which the Company is aware) which is in violation of law, or (iv) violated in any material respect any provision of the Foreign Corrupt Practices Act of 1977, as amended.

(cc)         Accountants.  The Company’s accounting firm is Ernst & Young LLP.  To the knowledge and belief of the Company, such accounting firm (i) is a registered public accounting firm as required by the Exchange Act and (ii) shall express its opinion with respect to the financial statements to be included in the Company’s Annual Report on Form 10-K for the year ending June 30, 2008.

(dd)         Acknowledgment Regarding Purchaser’s Purchase of Shares.  The Company acknowledges and agrees that the Purchaser is acting solely in the capacity of an arm’s length purchaser with respect to the Transaction Documents and the transactions contemplated thereby.  The Company further acknowledges that the Purchaser is not acting as a financial advisor or fiduciary of the Company (or in any similar capacity) with respect to the Transaction Documents and the transactions contemplated thereby and any advice given by the Purchaser or any of its representatives or agents in connection with the Transaction Documents and the transactions contemplated thereby is merely incidental to the Purchaser’s purchase of the Shares. The Company further represents to the Purchaser that the Company’s decision to enter into this Agreement and the other Transaction Documents has been based solely on the independent evaluation of the transactions contemplated hereby by the Company and its representatives.

(ee)         Acknowledgement Regarding Purchaser’s Trading Activity.  Anything in this Agreement or elsewhere herein to the contrary notwithstanding, it is understood and acknowledged by the Company (i) that the Purchaser has not been asked by the Company to agree, nor has the Purchaser agreed, to desist from purchasing or selling, long and/or short, securities of the Company, or “derivative” securities based on securities issued by the Company or to hold the Shares for any specified term; (ii) that past or future open market or other transactions by the Purchaser or any entity in which the Purchaser has an interest, specifically including, without limitation, Short Sales or “derivative” transactions, before or after the closing of this or future transactions, may negatively impact the market price of the Company’s publicly-traded securities; (iii) that the Purchaser, and counter-parties in “derivative” transactions to which the Purchaser is a party or in which the Purchaser has an interest, directly or indirectly, presently may have a “short” position in the Common Stock; and (iv) that the Purchaser shall not be deemed to have any affiliation with or control over any arm’s length counter-party in any “derivative” transaction. The Company further understands and acknowledges that (a) the Purchaser or any entity in which the Purchaser has an interest may engage in hedging activities at various times, and (b) such hedging activities (if any) could reduce the value

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of the existing stockholders’ equity interests in the Company at and after the time that the hedging activities are being conducted.  The Company acknowledges that such aforementioned hedging activities do not constitute a breach of any of the Transaction Documents.

(ff)           Regulation M Compliance.   The Company has not, and to its knowledge no one acting on its behalf has, (i) taken, directly or indirectly, any action designed to cause or to result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of any of the Shares, (ii) sold, bid for, purchased, or, paid any compensation for soliciting purchases of, any of the Shares, or (iii) paid or agreed to pay to any Person any compensation for soliciting another to purchase any other securities of the Company.

(gg)         FDA.  As to each product subject to the jurisdiction of the U.S. Food and Drug Administration (“FDA”) under the Federal Food, Drug and Cosmetic Act, as amended, and the regulations thereunder (“FDCA”) that is manufactured, packaged, labeled, tested, distributed, sold, and/or marketed by the Company or any of its Subsidiaries (each such product, a “Pharmaceutical Product”), such Pharmaceutical Product is being manufactured, packaged, labeled, tested, distributed, sold and/or marketed by the Company in compliance with all applicable requirements under FDCA and similar laws, rules and regulations relating to registration, investigational use, premarket clearance, licensure, or application approval, good manufacturing practices, good laboratory practices, good clinical practices, product listing, quotas, labeling, advertising, record keeping and filing of reports, except where the failure to be in compliance would not have a Material Adverse Effect.  There is no pending, completed or, to the Company’s knowledge, threatened, action (including any lawsuit, arbitration, or legal or administrative or regulatory proceeding, charge, complaint, or investigation) against the Company or any of its Subsidiaries, and none of the Company or any of its Subsidiaries has received any notice, warning letter or other communication from the FDA or any other governmental entity, which (i) contests the premarket clearance, licensure, registration, or approval of, the uses of, the distribution of, the manufacturing or packaging of, the testing of, the sale of, or the labeling and promotion of any Pharmaceutical Product, (ii) withdraws its approval of, requests the recall, suspension, or seizure of, or withdraws or orders the withdrawal of advertising or sales promotional materials relating to, any Pharmaceutical Product, (iii) imposes a clinical hold on any clinical investigation by the Company or any of its Subsidiaries, (iv) enjoins production at any facility of the Company or any of its Subsidiaries, (v) enters or proposes to enter into a consent decree of permanent injunction with the Company or any of its Subsidiaries, or (vi) otherwise alleges any violation of any laws, rules or regulations by the Company or any of its Subsidiaries, and which, either individually or in the aggregate, would have a Material Adverse Effect.  The properties, business and operations of the Company have been and are being conducted in all material respects in accordance with all applicable laws, rules and regulations of the FDA.  The Company has not been informed by the FDA that the FDA will prohibit the marketing, sale, license or use in the United States of any product proposed to be developed, produced or marketed by the Company nor has the FDA expressed any concern as to approving or clearing for

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marketing any product being developed or proposed to be developed by the Company.

3.2           Representations and Warranties of the Purchaser.  The Purchaser hereby represents and warrants as of the date hereof to the Company as follows:

(a)           Organization; Authority.  The Purchaser is an entity duly organized, validly existing and in good standing under the laws of the jurisdiction of its organization with full right, corporate or partnership power and authority to enter into and to consummate the transactions contemplated by this Agreement and otherwise to carry out its obligations hereunder and thereunder.  The execution and delivery of this Agreement and performance by the Purchaser of the transactions contemplated by this Agreement have been duly authorized by all necessary corporate or similar action on the part of the Purchaser.  Each Transaction Document to which it is a party has been duly executed by the Purchaser, and when delivered by the Purchaser in accordance with the terms hereof, will constitute the valid and legally binding obligation of the Purchaser, enforceable against it in accordance with its terms, except (i) as limited by general equitable principles and applicable bankruptcy, insolvency, reorganization, moratorium and other laws of general application affecting enforcement of creditors’ rights generally, (ii) as limited by laws relating to the availability of specific performance, injunctive relief or other equitable remedies and (iii) insofar as indemnification and contribution provisions may be limited by applicable law.

(b)           Own Account.  The Purchaser is acquiring the Shares as principal for its own account and not with a view to or for distributing or reselling such Shares or any part thereof in violation of the Securities Act or any applicable state securities law, has no present intention of distributing any of such Shares in violation of the Securities Act or any applicable state securities law and has no direct or indirect arrangement or understandings with any other persons to distribute or regarding the distribution of such Shares in violation of the Securities Act or any applicable state securities law (this representation and warranty not limiting the Purchaser’s right to sell the Shares immediately pursuant to Rule 144 or another applicable exemption from the registration requirements of the Securities Act or pursuant to a registration statement filed pursuant to the Registration Rights Agreement or otherwise in compliance with applicable federal and state securities laws).  The Purchaser is acquiring the Shares hereunder in the ordinary course of its business.

(c)           Purchaser Status.  At the time the Purchaser was offered the Shares, it was, and at the date hereof it is either: (i) an “accredited investor” as defined in Rule 501(a)(1), (a)(2), (a)(3), (a)(7) or (a)(8) under the Securities Act or (ii) a “qualified institutional buyer” as defined in Rule 144A(a) under the Securities Act.  The Purchaser is not required to be registered as a broker-dealer under Section 15 of the Exchange Act.  Neither BVF Partners L.P. nor BVF Inc. will beneficially own or control the Shares to be purchased by the Purchaser.

(d)           Experience of Purchaser.  The Purchaser, either alone or together with its representatives, has such knowledge, sophistication and experience in business and financial matters so as to be capable of evaluating the merits and risks of the prospective

18

investment in the Shares, and has so evaluated the merits and risks of such investment.  The Purchaser is able to bear the economic risk of an investment in the Shares and, at the present time, is able to afford a complete loss of such investment.

ARTICLE IV.
OTHER AGREEMENTS OF THE PARTIES

4.1           Furnishing of Information.  For so long as the Purchaser owns any Shares, (a) the Company covenants to timely file (or obtain extensions in respect thereof and file within the applicable grace period) all reports required to be filed by the Company after the date hereof pursuant to the Exchange Act even if the Company is not then subject to the reporting requirements of the Exchange Act and (b) if the Company is not required to file reports pursuant to the Exchange Act, it will prepare and furnish to the Purchaser and make publicly available in accordance with Rule 144(c) such information as is required for the Purchaser to sell the Shares under Rule 144.  The Company further covenants that it will take such further action as any holder of Shares may reasonably request, to the extent required from time to time to enable such Person to sell such Shares without registration under the Securities Act within the requirements of the exemption provided by Rule 144.

4.2           Integration.  The Company shall not sell, offer for sale or solicit offers to buy or otherwise negotiate in respect of any security (as defined in Section 2 of the Securities Act) that would be integrated with the offer or sale of the Shares for purposes of the rules and regulations of any Trading Market such that it would require shareholder approval prior to the closing of such other transaction unless shareholder approval is obtained before the closing of such subsequent transaction.

4.3           Securities Laws Disclosure; Publicity.  The Company shall, by 8:30 a.m. (New York City time) on the Trading Day immediately following the date hereof, issue a Current Report on Form 8-K, disclosing the material terms of the transactions contemplated hereby, and filing the Transaction Documents as exhibits thereto as well as the Prospectus Supplement.  The Company and the Purchaser shall consult with each other in issuing any other press releases with respect to the transactions contemplated hereby, and neither the Company nor the Purchaser shall issue any such press release or otherwise make any such public statement without the prior consent of the Company, with respect to any press release or public statement of the Purchaser, or without the prior consent of the Purchaser, with respect to any press release or public statement of the Company.  Notwithstanding the foregoing, the Company shall not publicly disclose the name of the Purchaser or any of its Affiliates, or include the name of the Purchaser or any of its Affiliates in any filing with the Commission (including the Form 8-K and the Prospectus Supplement referred to above) or any regulatory agency or Trading Market, without the prior written consent of the Purchaser, except that the Purchaser’s consent shall not be required with respect to subsequent regulatory filings by the Company if the disclosure in such subsequent regulatory filings is identical to the disclosure previously approved in writing by the Purchaser.

4.4           Shareholder Rights Plan.  No claim will be made or enforced by the Company or, with the consent of the Company, any other Person, that the Purchaser is an “Acquiring Person”

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under any control share acquisition, business combination, poison pill (including any distribution under a rights agreement) or similar anti-takeover plan or arrangement in effect or hereafter adopted by the Company, or that the Purchaser could be deemed to trigger the provisions of any such plan or arrangement, by virtue of receiving Shares under the Transaction Documents or under any other agreement between the Company and the Purchaser.

4.5           Non-Public Information.  Except with respect to the material terms and conditions of the transactions contemplated by the Transaction Documents, the Company covenants and agrees that neither it nor any other Person acting on its behalf will provide the Purchaser or its agents or counsel with any information that the Company believes constitutes material non-public information, unless prior thereto the Purchaser shall have executed a written agreement regarding the confidentiality and use of such information.  The Company understands and confirms that the Purchaser shall be relying on the foregoing covenant in effecting transactions in securities of the Company.

4.6           Use of Proceeds.  The Company shall use the net proceeds from the sale of the Shares hereunder for working capital purposes and shall not use such proceeds for (a) the satisfaction of any portion of the Company’s debt (other than payment of trade payables in the ordinary course of the Company’s business and prior practices) or (b) the redemption of any Common Stock or Common Stock Equivalents.

4.7           Indemnification of Purchaser.  Subject to the provisions of this Section 4.7, the Company will indemnify and hold the Purchaser and its directors, officers, shareholders, members, partners, employees and agents (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title), each Person who controls the Purchaser (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the directors, officers, shareholders, agents, members, partners or employees (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title) of such controlling persons (each, a “Purchaser Party”) harmless from any and all losses, liabilities, obligations, claims, contingencies, damages, costs and expenses, including all judgments, amounts paid in settlements, court costs and reasonable attorneys’ fees and costs of investigation that any Purchaser Party may suffer or incur (collectively, “Losses”) as a result of or relating to (a) any breach of any of the representations or warranties made by the Company in this Agreement or in the other Transaction Documents (without regard to any “materiality” or Material Adverse Effect” qualifiers contained therein), to the extent that the amount of the Losses arising from all such breaches exceeds $500,000, (b) any breach of any of the covenants or agreements made by the Company in this Agreement or in the other Transaction Documents (without regard to any “materiality” or Material Adverse Effect” qualifiers contained therein) and (c) any action instituted against any Purchaser Party in any capacity, or any of them or their respective Affiliates, by any stockholder of the Company who is not an Affiliate of the Purchaser, with respect to any of the transactions contemplated by the Transaction Documents (unless such action is based upon a breach of the Purchaser’s representations, warranties or covenants under the Transaction Documents or any agreements or understandings the Purchaser may have with any such stockholder or any violations by the Purchaser of state or federal securities laws or any conduct by the Purchaser which constitutes fraud, gross negligence, willful misconduct or

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malfeasance).  If any action shall be brought against any Purchaser Party in respect of which indemnity may be sought pursuant to this Agreement, such Purchaser Party shall promptly notify the Company in writing, and the Company shall have the right to assume the defense thereof with counsel of its own choosing reasonably acceptable to the Purchaser Party.  Any Purchaser Party shall have the right to employ separate counsel in any such action and participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such Purchaser Party except to the extent that (i) the employment thereof has been specifically authorized by the Company in writing, (ii) the Company has failed after a reasonable period of time to assume such defense and to employ counsel, or (iii) in such action there is, in the reasonable opinion of such separate counsel, a material conflict on any material issue between the position of the Company and the position of such Purchaser Party, in which case the Company shall be responsible for the reasonable fees and expenses of no more than one such separate counsel (and local counsel).  The Company will not be liable to any Purchaser Party under this Agreement for any settlement by a Purchaser Party effected without the Company’s prior written consent, which shall not be unreasonably withheld or delayed.

4.8           Listing of Common Stock.  The Company hereby agrees to use commercially reasonable efforts to maintain the listing of the Common Stock on a Trading Market and, agrees that no later than the Closing Date, all of the Shares will be listed on such Trading Market.  The Company further agrees, if the Company applies to have the Common Stock traded on any other Trading Market, it will include in such application all of the Shares, and will take such other action as is necessary to cause all of the Shares to be listed on such other Trading Market as promptly as possible.  The Company will take all action reasonably necessary to continue the listing and trading of its Common Stock on a Trading Market and will comply in all respects with the Company’s reporting, filing and other obligations under the bylaws or rules of the Trading Market.

ARTICLE V.
MISCELLANEOUS

5.1           Fees and Expenses.  Except as expressly set forth in the Transaction Documents to the contrary, each party shall pay the fees and expenses of its advisers, counsel, accountants and other experts, if any, and all other expenses incurred by such party incident to the negotiation, preparation, execution, delivery and performance of this Agreement.  The Company shall pay all Transfer Agent fees, stamp taxes and other taxes and duties levied in connection with the delivery of the Shares to the Purchaser.

5.2           Entire Agreement.  The Transaction Documents, together with the exhibits and schedules thereto, the Prospectus and the Prospectus Supplement, contain the entire understanding of the parties with respect to the subject matter hereof and supersede all prior agreements and understandings, oral or written, with respect to such matters, which the parties acknowledge have been merged into such documents, exhibits and schedules.

5.3           Notices.  Any and all notices or other communications or deliveries required or permitted to be provided hereunder shall be in writing and shall be deemed given and effective

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on the earliest of (a) the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number set forth on the signature pages attached hereto prior to 5:30 p.m. (New York City time) on a Trading Day, (b) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number set forth on the signature pages attached hereto on a day that is not a Trading Day or later than 5:30 p.m. (New York City time) on any Trading Day, (c) the 2nd Trading Day following the date of mailing, if sent by U.S. nationally recognized overnight courier service, or (d) upon actual receipt by the party to whom such notice is required to be given.  The addresses for such notices and communications shall be as follows:

(a)  If to the Company:

ImmunoGen, Inc.

830 Winter Street

Waltham, MA 02451

Fax:  (781) 895-0613

Attn:  General Counsel

with a copy (which shall not constitute notice) to:

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

One Financial Center

Boston, MA 02111

Fax:  (617) 542-2241

Attn:  Jonathan L. Kravetz, Esq.

(b)  If to the Purchaser:

Ziff Brothers Investments

350 Park Avenue

New York, NY  10022

Attention:  General Counsel

Fax:  (212) 292-6659

with a copy (which shall not constitute notice) to:

Fried, Frank, Harris, Shriver & Jacobson LLP
One New York Plaza
New York, New York 10004
Attention:  Jonathan Adler, Esq.

Fax:  (212) 859-4000

5.4           Amendments; Waivers.  No provision of this Agreement may be waived or amended except in a written instrument signed by the Company and the Purchaser or, in the case of a waiver, by the party against whom enforcement of any such waived provision is sought.  No waiver of any default with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing waiver in the future or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay or omission

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of any party to exercise any right hereunder in any manner impair the exercise of any such right.

5.5           Headings.  The headings herein are for convenience only, do not constitute a part of this Agreement and shall not be deemed to limit or affect any of the provisions hereof.

5.6           Successors and Assigns.  This Agreement shall be binding upon and inure to the benefit of the parties and their successors and permitted assigns.  The Company may not assign this Agreement or any rights or obligations hereunder without the prior written consent of the Purchaser (other than by merger).  The Purchaser may assign any or all of its rights under this Agreement to any Person to whom the Purchaser assigns or transfers any Shares.

5.7           No Third-Party Beneficiaries.  This Agreement is intended for the benefit of the parties hereto and their respective successors and permitted assigns and is not for the benefit of, nor may any provision hereof be enforced by, any other Person, except as otherwise set forth in Section 4.8.

5.8           Governing Law.  All questions concerning the construction, validity, enforcement and interpretation of the Transaction Documents shall be governed by and construed and enforced in accordance with the internal laws of the State of New York, without regard to the principles of conflicts of law thereof.  Each party agrees that all legal proceedings concerning the interpretations, enforcement and defense of the transactions contemplated by this Agreement and any other Transaction Documents (whether brought against a party hereto or its respective affiliates, directors, officers, shareholders, employees or agents) shall be commenced exclusively in the state and federal courts sitting in the City of New York.  Each party hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of New York, borough of Manhattan for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein (including with respect to the enforcement of any of the Transaction Documents), and hereby irrevocably waives, and agrees not to assert in any suit, action or proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such suit, action or proceeding is improper or is an inconvenient venue for such proceeding.  Each party hereby irrevocably waives personal service of process and consents to process being served in any such suit, action or proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Agreement and agrees that such service shall constitute good and sufficient service of process and notice thereof.  Nothing contained herein shall be deemed to limit in any way any right to serve process in any other manner permitted by law.  If either party shall commence an action or proceeding to enforce any provisions of the Transaction Documents, then the prevailing party in such action or proceeding shall be reimbursed by the other party for its reasonable attorneys’ fees and other costs and expenses incurred with the investigation, preparation and prosecution of such action or proceeding.

5.9           Survival.  The representations and warranties contained herein shall survive the Closing and the delivery of the Shares.

5.10         Execution.  This Agreement may be executed in two or more counterparts, all of which when taken together shall be considered one and the same agreement and shall become

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effective when counterparts have been signed by each party and delivered to the other party, it being understood that both parties need not sign the same counterpart.  In the event that any signature is delivered by facsimile transmission or by e-mail delivery of a “.pdf” format data file, such signature shall create a valid and binding obligation of the party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf” signature page were an original thereof.

5.11         Severability.  If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction to be invalid, illegal, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions set forth herein shall remain in full force and effect and shall in no way be affected, impaired or invalidated, and the parties hereto shall use their commercially reasonable efforts to find and employ an alternative means to achieve the same or substantially the same result as that contemplated by such term, provision, covenant or restriction.  It is hereby stipulated and declared to be the intention of the parties that they would have executed the remaining terms, provisions, covenants and restrictions without including any of such that may be hereafter declared invalid, illegal, void or unenforceable.

5.12         Replacement of Shares.  If any certificate or instrument evidencing any Shares is mutilated, lost, stolen or destroyed, the Company shall issue or cause to be issued in exchange and substitution for and upon cancellation thereof (in the case of mutilation), or in lieu of and substitution therefor, a new certificate or instrument (without any restrictive legends), but only upon receipt of evidence reasonably satisfactory to the Company of such loss, theft or destruction.  The applicant for a new certificate or instrument under such circumstances shall also pay any reasonable third-party costs (including customary indemnity) associated with the issuance of such replacement Shares.

5.13         Remedies.  In addition to being entitled to exercise all rights provided herein or granted by law, including recovery of damages, the Purchaser will be entitled to specific performance under the Transaction Documents.  The parties agree that monetary damages may not be adequate compensation for any loss incurred by reason of any breach of the Company’s obligations contained in the Transaction Documents and the Company hereby agrees to waive and not to assert in any action for specific performance of any such obligation the defense that a remedy at law would be adequate.

5.14         Saturdays, Sundays, Holidays, etc.  If the last or appointed day for the taking of any action or the expiration of any right required or granted herein shall not be a Business Day, then such action may be taken or such right may be exercised on the next succeeding Business Day.

5.15         Construction.  The parties agree that each of them and/or their respective counsel has reviewed and had an opportunity to revise the Transaction Documents and, therefore, the normal rule of construction to the effect that any ambiguities are to be resolved against the drafting party shall not be employed in the interpretation of the Transaction Documents or any amendments hereto.

5.16         Waiver of Jury Trial.  In any action, suit or proceeding in any jurisdiction brought by any party against any other party, the parties each knowingly and intentionally, to the greatest

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extent permitted by applicable law, hereby absolutely, unconditionally, irrevocably and expressly waives forever trial by jury.

(Signature Page Follows)

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed by their respective authorized signatories as of the date first indicated above.

[Signature Page to Securities Purchase Agreement]

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Exhibit C

1.             Mitchel Sayare

2.             David W. Carter

3.             Stephen C. McCluski

4.             Nicole Onetto

5.             Mark Skaletsky

6.             Joseph J. Villafranca

7.             Daniel M. Junius

8.             John M. Lambert

9.             John Tagliamonte

10.           Richard J. Wallace

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Exhibit 10.2

EXECUTION COPY

REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (this “Agreement”) is made and entered into as of June 20, 2008, by and between ImmunoGen, Inc., a Massachusetts corporation (the “Company”), and Ziff Asset Management, L.P., a Delaware limited partnership (the “Purchaser”).

This Agreement is made pursuant to the Securities Purchase Agreement, dated as of June 20, 2008, between the Company and the Purchaser (the “Purchase Agreement”).

NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in this Agreement, and for other good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the Company and the Purchaser agree as follows:

1.  Definitions.  Capitalized terms used and not otherwise defined herein that are defined in the Purchase Agreement shall have the meanings given such terms in the Purchase Agreement. As used in this Agreement, the following terms shall have the respective meanings set forth in this Section 1:

“Commission” means the United States Securities and Exchange Commission or any other federal agency at the time administering the Securities Act.

“Common Stock” means the common stock, par value $0.01 per share, of the Company.

“Effective Date” means the date that the Registration Statement filed pursuant to Section 2(a) is first declared effective by the Commission.

“Effectiveness Date” means: (a) with respect to the Initial Registration Statement, the 90th day following the Closing, (b) with respect to any additional Registration Statements that may be required pursuant to Section 2 hereof, the 90th day following the date on which the Company first knows, or reasonably should have known, that such additional Registration Statement is required under such Section.

“Effectiveness Period” shall have the meaning set forth in Section 2(a).

“Event” shall have the meaning set forth in Section 2(c).

“Event Date” shall have the meaning set forth in Section 2(c).

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“Filing Date” means: (a) with respect to the initial Registration Statement required to be filed to cover the resale by the Holders of the Registrable Securities, the 45th day following the Closing, and (b) with respect to any additional Registration Statements that may be required pursuant to Section 2 hereof, the 45th day following the date on which the Company first knows,

or reasonably should have known, that such additional Registration Statement is required under such Section.

“Holder” or “Holders” means the holder or holders, as the case may be, from time to time of Registrable Securities.

“Indemnified Party” shall have the meaning set forth in Section 5(c)(i).

“Indemnifying Party” shall have the meaning set forth in Section 5(c)(i).

“Initial Registration Statement” shall mean the initial Registration Statement required to be filed to cover the resale by the Holders of the Registrable Securities pursuant to Section 2(a).

“Inspectors” shall have the meaning set forth in Section 3(l).

“Losses” shall have the meaning set forth in Section 5(a).

“Person” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“Proceeding” means an action, claim, suit, investigation or proceeding (including, without limitation, an investigation or partial proceeding, such as a deposition), whether commenced or threatened.

“Prospectus” means the prospectus included in a Registration Statement (including, without limitation, a prospectus that includes any information previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A or Rule 430B promulgated under the Securities Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by a Registration Statement, and all other amendments and supplements to the Prospectus, including post-effective amendments, and all material incorporated by reference or deemed to be incorporated by reference in such Prospectus.

“Reduction Securities” shall have the meaning set forth in Section 2(d).

“Registrable Securities” means (i) the Shares issued pursuant to the Purchase Agreement and (ii) any other shares of Common Stock issued as (or issuable upon conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, in exchange for or in replacement of the Shares; provided, however, that Shares which are Registrable Securities shall cease to be Registrable Securities upon the earlier of (x) any sale of such Registrable Securities pursuant to a Registration Statement or Rule 144, or (y) following any sale of such Registrable Securities by the Purchaser (other than pursuant to a Registration Statement or Rule 144) to any Person other than an Affiliate of the Purchaser who, after giving effect to such sale, owns less than 10% of the outstanding shares of Common Stock, at such time as such Person is able to sell all of his or its Registrable Securities

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pursuant to Rule 144(b)(1).

“Registration Statement” means each of the following: (i) the Initial Registration Statement, and (ii) each additional registration statement, if any, contemplated by Section 2, and including, in each case, the Prospectus, amendments and supplements to each such registration statement or Prospectus, including pre- and post-effective amendments, all exhibits thereto, and all material incorporated by reference or deemed to be incorporated by reference in such registration statement.

“Rule 144” means Rule 144 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as such Rule.

“Rule 415” means Rule 415 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as such Rule.

“Rule 424” means Rule 424 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as such Rule.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“Shares” shall have the meaning set forth in the Purchase Agreement.

“Trading Day” shall have the meaning set forth in the Purchase Agreement.

2.  Registration.

(a)       On or prior to each Filing Date, the Company shall prepare and file with the Commission a Registration Statement covering the resale of all Registrable Securities not already covered by an existing and effective Registration Statement (except as provided in Section 2(b) and Section 2(d)) for an offering to be made on a continuous basis pursuant to Rule 415. The Registration Statement shall be on Form S-3 (except if the Company is not then eligible to register for resale the Registrable Securities on Form S-3, in which case such registration shall be on another appropriate form for such purpose reasonably acceptable to the Purchaser) and shall contain (except if otherwise required pursuant to written comments received from the Commission upon a review of such Registration Statement) the “Plan of Distribution” in substantially the form attached hereto as Annex A, with such changes as may be requested by the Holders. The Company shall use its commercially reasonable efforts to cause each Registration Statement to be declared effective under the Securities Act as soon as possible after the respective dates of filing thereof, but, in any event, no later than the Effectiveness Date for such Registration Statement, and shall use its commercially reasonable efforts to keep the Registration Statement continuously effective under the Securities Act until the date on which all Registrable Securities covered by such Registration Statement have ceased to be Registrable Securities (the “Effectiveness Period”), subject to Section 6(d) hereof. It is agreed and understood that the

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Company shall, from time to time, be obligated to file one or more additional Registration Statements to cover any Registrable Securities which are not registered for resale pursuant to a pre-existing Registration Statement.

(b)       Notwithstanding anything contained herein to the contrary, including the fact that such Registrable Securities may be registered pursuant to the Registration Statement referred to in Section 2(d) below, in the event that the Commission limits the amount of Registrable Securities that may be included and sold by Holders in any Registration Statement, including the Initial Registration Statement, pursuant to Rule 415 or any other basis, the Company may reduce the number of Registrable Securities included in such Registration Statement on behalf of the Holders (in proportion to the respective numbers of Registrable Securities represented by Shares held by such Holders ). In such event the Company shall give the Holders prompt notice of the number of the Registrable Securities excluded and the Company will not be liable for any liquidated damages under Section 2(c), or otherwise under this Agreement, in connection with the excluded Registrable Securities. The Company shall use its commercially reasonable efforts at the first opportunity that is permitted by the Commission to register for resale the Registrable Securities that were excluded from being registered on such Registration Statement. Such new Registration Statement shall be on Form S-3 (except if the Company is not then eligible to register for resale the Registrable Securities on Form S-3, in which case such registration shall be on another appropriate form for such purpose reasonably acceptable to the Purchaser) and shall contain (except if otherwise required pursuant to written comments received from the Commission upon a review of such Registration Statement) the “Plan of Distribution” in substantially the form attached hereto as  Annex A, with such changes as the Holders may request. The Company shall use its commercially reasonable efforts to cause each such Registration Statement to be declared effective under the Securities Act as soon as possible after the respective dates of filing thereof, but, in any event, no later than the Effectiveness Date for such Registration Statement, and shall use its commercially reasonable efforts to keep such Registration Statement continuously effective under the Securities Act during the entire Effectiveness Period, subject to Section 6(d) hereof.

(c)       Except as provided in Section 2(b), if: (i) a Registration Statement is not filed on or prior to its Filing Date, (ii) a Registration Statement is not declared effective by the Commission on or prior to its required Effectiveness Date, or (iii) after its Effective Date, such Registration Statement ceases for any reason to be effective and available to the Holders as to all Registrable Securities to which it is required to cover at any time prior to the expiration of its Effectiveness Period for an aggregate of more than 20 consecutive Trading Days or an aggregate of 50 Trading Days (which need not be consecutive) in any given 360-day period, (any such failure or breach being referred to as an “Event,” and for purposes of clauses (i) or (ii) the date on which such Event occurs, and for purposes of clause (iii) the date on which such 20 consecutive or 50 Trading Day-period (as applicable) is exceeded, being referred to as the “Event Date”), then, in addition to any other rights available to the Holders: (x) on such Event Date the Company shall pay to each Holder an amount in cash, as liquidated damages and not as a penalty, equal to 1% of the aggregate purchase price paid by such Holder pursuant to the Purchase Agreement for its Registrable Securities then held; and (y) on each monthly anniversary of each such Event Date (if the applicable Event shall not have been cured by such date) until the applicable Event is cured, the Company shall pay to each Holder an amount in

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cash, as partial liquidated damages and not as a penalty, equal to 1% of the aggregate purchase price paid by such Holder pursuant to the Purchase Agreement for its Registrable Securities then held; provided, that all periods shall be tolled, with respect to a Holder, by the number of Trading Days during which such Holder fails to provide the Company with information regarding such Holder which was reasonably requested by the Company in order to effect the registration of such Holder’s Registrable Securities pursuant to Section 6(e) hereof. The partial liquidated damages pursuant to the terms hereof shall apply on a pro rata basis for any portion of a month prior to the cure of an Event.

(d)       In the event that the number of Registrable Securities included in the Initial Registration Statement or any subsequent Registration Statement are reduced as provided in Section 2(b) above (such Registrable Securities, the “Reduction Securities”), the Company shall prepare and file with the Commission a Registration Statement covering the resale of the Reduction Securities on Form S-1 (or another appropriate form for such purpose reasonably acceptable to the Purchaser). The Registration Statement shall contain (except if otherwise required pursuant to written comments received from the Commission upon a review of such Registration Statement) the “Plan of Distribution” in substantially the form attached hereto as Annex A, with such changes as the Holders may request. The Company shall use its commercially reasonable efforts to cause such Registration Statement to be declared effective under the Securities Act as soon as possible after the date of filing thereof, but, in any event, no later than the Effectiveness Date for such Registration Statement, and shall use its commercially reasonable efforts to keep the Registration Statement continuously effective under the Securities Act for the Effectiveness Period, subject to Section 6(d) hereof. In the event that any Reduction Securities become registered pursuant to a Registration Statement on Form S-3 pursuant to Section 2(b) or otherwise, such Reduction Securities may be removed from the Registration Statement on Form S-1 contemplated by this Section 2(d).

3.  Registration Procedures.  In connection with the Company’s registration obligations hereunder, the Company shall:

(a)       Not less than five Trading Days prior to the filing of a Registration Statement or any related Prospectus or any amendment or supplement thereto, the Company shall furnish to the Holders copies of all such documents proposed to be filed (other than those incorporated by reference). In the event that any Registration Statement is on Form S-1 (or other form which does not permit incorporation by reference), the Company shall not be required to furnish to the Holders any prospectus supplement containing information included in a report or proxy statement filed under the Exchange Act that would be incorporated by reference in such Registration Statement if such Registration Statement were on Form S-3 (or other form which permits incorporation by reference). The Company shall duly consider any comments made by Holders and received by the Company not later than two Trading Days prior to the filing of the Registration Statement, and shall not file any Registration Statement or any related Prospectus or any amendment or supplement thereto in a form to which such Holders reasonably object.

(b)       (i) Prepare and file with the Commission such amendments, including post-effective amendments, to each Registration Statement and the Prospectus used in connection therewith as may be necessary to keep such Registration Statement continuously effective as to

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the applicable Registrable Securities for its Effectiveness Period and prepare and file with the Commission such additional Registration Statements in order to register for resale under the Securities Act all of the Registrable Securities; (ii) cause the related Prospectus to be amended or supplemented by any required Prospectus supplement, and as so supplemented or amended to be filed pursuant to Rule 424; (iii) respond as promptly as reasonably possible to any comments received from the Commission with respect to each Registration Statement or any amendment thereto and, as promptly as reasonably possible provide the Holders true and complete copies of all correspondence from and to the Commission relating to such Registration Statement, excluding any comments that would result in the disclosure to the Holders of material and non-public information concerning the Company; and (iv) comply in all material respects with the provisions of the Securities Act and the Exchange Act with respect to the Registration Statements and the disposition of all Registrable Securities covered by each Registration Statement.

(c)       Notify the Holders as promptly as reasonably possible (and, in the case of clause (i)(A) below, not less than five Trading Days prior to such filing) and confirm such notice in writing no later than one Trading Day following the day: (i)(A) when a Prospectus or any prospectus supplement (but only to the extent notice is required under Section 3(a) above) or post-effective amendment to a Registration Statement is proposed to be filed; (B) when the Commission notifies the Company whether there will be a “review” of such Registration Statement and whenever the Commission comments in writing on such Registration Statement (in which case the Company shall provide true and complete copies thereof and all written responses thereto to each of the Holders, excluding information that the Company believes would constitute material and non-public information regarding the Company); and (C) with respect to each Registration Statement or any post-effective amendment, when the same has been declared effective; (ii) of any request by the Commission or any other Federal or state governmental authority for amendments or supplements to a Registration Statement or Prospectus or for additional information that pertains to the Holders as Selling Stockholders or the Plan of Distribution; (iii) of the issuance by the Commission of any stop order suspending the effectiveness of a Registration Statement covering any or all of the Registrable Securities or the initiation of any Proceedings for that purpose; (iv) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of any of the Registrable Securities for sale in any jurisdiction, or the initiation or threatening of any Proceeding for such purpose; (v) of the occurrence of any event or passage of time that makes the financial statements included or incorporated by reference in a Registration Statement ineligible for inclusion or incorporation by reference therein or any statement made in such Registration Statement or Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue in any material respect or that requires any revisions to such Registration Statement, Prospectus or other documents so that, in the case of such Registration Statement or the Prospectus, as the case may be, it will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading; and (vi) of the occurrence or existence of any pending corporate development with respect to the Company that the Company believes may be material and that, in the determination of the Company, makes it not in the best interest of the Company to allow continued availability of a Registration Statement or Prospectus; provided, that any and all of

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such information shall remain confidential to each Holder until such information otherwise becomes public, unless disclosure by a Holder is required by law;  provided, further, that notwithstanding each Holder’s agreement to keep such information confidential, each such Holder makes no acknowledgement that any such information is material, non-public information.

(d)       Use its commercially reasonable efforts to prevent the issuance of, or, if issued, obtain the withdrawal of (i) any order suspending the effectiveness of a Registration Statement, or (ii) any suspension of the qualification (or exemption from qualification) of any of the Registrable Securities for sale in any jurisdiction, at the earliest practicable moment and to notify each Holder who holds Registrable Securities being sold of the issuance of any such order and the resolution thereof or its receipt of actual notice of the initiation or threat of any proceeding for such purpose.

(e)       Furnish to each Holder, without charge, at least one conformed copy of each Registration Statement and each amendment thereto and all exhibits to the extent reasonably requested by such Person (including those previously furnished or incorporated by reference) promptly after the filing of such documents with the Commission.

(f)        Promptly deliver to each Holder, without charge, (i) as many copies of each Prospectus or Prospectuses (including each form of prospectus) and each amendment or supplement thereto as such Persons may reasonably request and (ii) such other documents, including copies of any preliminary or final prospectus, as such Holder may reasonably request from time to time in order to facilitate the disposition of the Registrable Securities owned by such Holder. Subject to Section 6(d) hereof, the Company hereby consents to the use of such Prospectus and each amendment or supplement thereto by each of the selling Holders in connection with the offering and sale of the Registrable Securities covered by such Prospectus and any amendment or supplement thereto.

(g)       Prior to any public offering of Registrable Securities, use its commercially reasonable efforts to (i) register or qualify or cooperate with the selling Holders in connection with the registration or qualification (or exemption from such registration or qualification) of such Registrable Securities for offer and sale under the securities or Blue Sky laws of those jurisdictions within the United States as any Holder reasonably requests in writing to keep each such registration or qualification (or exemption therefrom) effective during the Effectiveness Period, (ii) prepare and file in those jurisdictions such amendments (including post-effective amendments) and supplements to such registrations and qualifications as may be necessary to maintain the effectiveness thereof during the Effectiveness Period, (iii) take such other actions as may be reasonably necessary to maintain such registrations and qualifications in effect at all times during the Effectiveness Period and (iv) to do any and all other acts or things necessary or advisable to enable the disposition in such jurisdictions of the Registrable Securities covered by the Registration Statements; provided, that the Company shall not be required to qualify generally to do business in any jurisdiction where it is not then qualified, or subject the Company to any material tax in any such jurisdiction where it is not then so subject, or file a general consent to service of process in any such jurisdiction.

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(h)       If requested by the Holders, cooperate with the Holders to facilitate the timely preparation and delivery of certificates representing Registrable Securities to be delivered to a transferee pursuant to the Registration Statements, which certificates shall be free of all restrictive legends, and to enable such Registrable Securities to be in such denominations and registered in such names as any such Holders may request.

(i)        Upon the occurrence of any event contemplated by Section 3(c)(vi), as promptly as reasonably possible, prepare a supplement or amendment, including a post-effective amendment, to the affected Registration Statements or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, and file any other required document so that, as thereafter delivered, no Registration Statement nor any Prospectus will contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.  If the Company notifies the Holders in accordance with Section 3(c)(vi) to suspend the use of any Prospectus until the requisite changes to such Prospectus have been made, then the Holders shall suspend use of such Prospectus.  The Company will use its commercially reasonable efforts to ensure that the use of the Prospectus may be resumed as promptly as is practicable.  The Company shall be entitled to exercise its right to suspend the availability of a Registration Statement and Prospectus for a period not to exceed sixty (60) calendar days (which need not be consecutive days) in any 12-month period.

(j)        The Company may require each selling Holder to furnish to the Company a certified statement as to the number of shares of Common Stock beneficially owned by such Holder and any Affiliate thereof, and, if required by the Commission, the natural persons thereof that have voting and dispositive control over the shares.

(k)       If any Holder reasonably requests, the Company shall use its commercially reasonable efforts to obtain an opinion from the Company’s counsel and a “comfort” letter from the Company’s independent public accountants in customary form and covering such matters as are customarily covered by such opinions and “comfort” letters delivered to underwriters in underwritten public offerings, which opinion and letter shall be reasonably satisfactory to the underwriter, if any, and furnish, on the date of the effectiveness of the Registration Statement and thereafter from time to time on such dates as a Holder may reasonably request, to each Holder participating in the offering and to each underwriter, if any, a copy of such opinion and letter addressed to such Holder or underwriter.

(l)        If any Holder reasonably requests, the Company shall promptly make available for inspection by (i) such Holder, (ii) its legal counsel and (iii) one firm of accountants or other agents retained by the Holders (collectively, the “Inspectors”), all pertinent financial and other records, and pertinent corporate documents and properties of the Company, as shall be reasonably deemed necessary by each Inspector, and cause the Company’s officers, directors and employees to supply all information which any Inspector may reasonably request; provided, however, that if any such information is designated by the Company as being confidential, upon request by the Company, such Holder shall enter into a customary confidentiality agreement with respect to such information.  Each Holder agrees that any non-public information obtained by it as a result of such inspections shall be deemed confidential and acknowledges its obligations

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under the federal securities laws not to trade any securities of the Company on the basis of material non-public information. In addition, the Company shall not be obligated under this section to disclose any information that is subject to a confidentiality agreement between the Company and any third party, provided that the Company shall use its commercially reasonable efforts to seek the appropriate third party consent to such disclosure to the Inspectors and, in connection with an underwritten offering, the Company shall provide any such information to the underwriter of such offering and its legal counsel, pursuant to customary due diligence procedures for underwritten securities offerings. Nothing herein (or in any other confidentiality agreement between the Company and any Holder) shall be deemed to limit the Holders’ ability to sell Registrable Securities in a manner which is otherwise consistent with applicable laws and regulations.

(m)      The Company shall hold in confidence and not make any disclosure of information concerning a Holder provided to the Company unless (i) disclosure of such information is necessary to comply with federal or state securities laws, (ii) the disclosure of such information is necessary to avoid or correct a misstatement or omission in any Registration Statement, (iii) the release of such information is ordered pursuant to a subpoena or other final, non-appealable order from a court or governmental body of competent jurisdiction, or (iv) such information has been made generally available to the public other than by disclosure in violation of this Agreement or any other agreement. The Company agrees that it shall, upon learning that disclosure of such information concerning a Holder is sought in or by a court or governmental body of competent jurisdiction or through other means, give prompt written notice to such Holder and allow such Holder, at the Holder’s expense, to undertake appropriate action to prevent disclosure of, or to obtain a protective order for, such information.

(n)       Enter into such customary agreements (including, if applicable, an underwriting agreement) and take such other actions as the Holders participating in such offering shall reasonably request in order to expedite or facilitate the disposition of their Registrable Securities (it being understood that the Holders of the Registrable Securities which are to be distributed by any underwriters shall be parties to any such underwriting agreement and may, at their option, require that the Company make to and for the benefit of such Holders the representations, warranties and covenants and indemnifications of the Company which are being made to and for the benefit of such underwriters).

4.  Registration Expenses.  All fees and expenses incident to the Company’s performance of or compliance with its obligations under this Agreement (excluding any underwriting discounts and selling commissions) shall be borne by the Company whether or not any Registrable Securities are sold pursuant to a Registration Statement. The fees and expenses referred to in the foregoing sentence shall include, without limitation, (i) all registration and filing fees (including, without limitation, fees and expenses (A) with respect to filings required to be made with the Trading Market on which the Common Stock is then listed for trading, and (B) in compliance with applicable state securities or Blue Sky laws), (ii) printing expenses (including, without limitation, expenses of printing certificates for Registrable Securities and of printing prospectuses if the printing of prospectuses is reasonably requested by the holders of a majority of the Registrable Securities included in the Registration Statement), (iii) messenger, telephone and delivery expenses, (iv) reasonable fees and disbursements of counsel for the

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Company, (v) Securities Act liability insurance, if the Company so desires such insurance, (vi) fees and disbursements of all independent certified public accountants (including, without limitation, the expenses of any “comfort” letters), and (vii) reasonable fees and expenses of all other Persons retained by the Company in connection with the consummation of the transactions contemplated by this Agreement. In addition, the Company shall be responsible for all of its internal expenses incurred in connection with the consummation of the transactions contemplated by this Agreement (including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expense of any annual audit and the fees and expenses incurred in connection with the listing of the Registrable Securities on any securities exchange as required hereunder.  The Company shall reimburse the Holders for the fees and disbursements of one legal counsel representing the Holders in connection with registration, filing or qualification pursuant to Sections 2 and 3 of this Agreement which amount shall be limited to $25,000.

5.  Indemnification.

(a)       Indemnification by the Company.  The Company shall, notwithstanding any termination of this Agreement, indemnify and hold harmless each Holder, the officers, directors, agents, partners, members, stockholders and employees of each Holder, each Person who controls any such Holder (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) and the officers, directors, agents, partners, members, stockholders and employees of each such controlling Person, to the fullest extent permitted by applicable law, from and against any and all losses, claims, damages, liabilities, costs (including, without limitation, reasonable costs of preparation and reasonable attorneys’ fees) and expenses (collectively, “Losses”), as incurred, arising out of or relating to (i) any untrue or alleged untrue statement of a material fact contained in any Registration Statement, any Prospectus or any form of prospectus or in any amendment or supplement thereto, (ii) any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any Prospectus or form of prospectus or supplement thereto, in light of the circumstances under which they were made) not misleading, (iii) any violation or alleged violation by the Company of the Securities Act, the Exchange Act, any other law, including, without limitation, any state securities law, or any rule or regulation thereunder relating to the offer or sale of the Registrable Securities pursuant to a Registration Statement and (iv) any violation of this Agreement, except to the extent, but only to the extent, that, with respect to clauses (i) and (ii), such untrue statements, alleged untrue statements, omissions or alleged omissions are based solely upon information regarding such Holder furnished in writing to the Company by such Holder expressly for use therein. The Company shall notify the Holders promptly of the institution, threat or assertion of any Proceeding of which the Company is aware in connection with the transactions contemplated by this Agreement.

(b)       Indemnification by Holders.  Each Holder shall, notwithstanding any termination of this Agreement, severally and not jointly, indemnify and hold harmless the Company, its directors, officers, agents and employees, each Person who controls the Company (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the directors, officers, agents, partners, members, stockholders or employees of such controlling Persons, to the fullest extent permitted by applicable law, from and against all Losses, as

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incurred, arising solely out of or based solely upon any untrue statement of a material fact contained in any Registration Statement, any Prospectus, or any form of prospectus, or in any amendment or supplement thereto, or arising solely out of or based solely upon any omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any Prospectus, or any form of prospectus or supplement thereto, in light of the circumstances under which they were made) not misleading to the extent, but only to the extent that, such untrue statements or omissions are based solely upon information regarding such Holder furnished in writing to the Company by such Holder expressly for use therein. In no event shall the liability of any selling Holder hereunder be greater in amount than the dollar amount of the net proceeds received by such Holder upon the sale of the Registrable Securities giving rise to such indemnification obligation.

(c)       Conduct of Indemnification Proceedings.

(i)        If any Proceeding shall be brought or asserted against any Person entitled to indemnity hereunder (an “Indemnified Party”), such Indemnified Party shall promptly notify the Person from whom indemnity is sought (the “Indemnifying Party”) in writing, and the Indemnifying Party shall assume the defense thereof, including the employment of counsel reasonably satisfactory to the Indemnified Party and the payment of all fees and expenses incurred in connection with defense thereof; provided, that the failure of any Indemnified Party to give such notice shall not relieve the Indemnifying Party of its obligations or liabilities pursuant to this Agreement, except (and only) to the extent that it shall be finally determined by a court of competent jurisdiction (which determination is not subject to appeal or further review) that such failure shall have proximately and materially adversely prejudiced the Indemnifying Party.

(ii)       An Indemnified Party shall have the right to employ separate counsel in any such Proceeding and to participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such Indemnified Party or Parties unless: (1) the Indemnifying Party has agreed in writing to pay such fees and expenses; (2) the Indemnifying Party shall have failed promptly to assume the defense of such Proceeding and to employ counsel reasonably satisfactory to such Indemnified Party in any such Proceeding; or (3) the named parties to any such Proceeding (including any impleaded parties) include both such Indemnified Party and the Indemnifying Party, and such Indemnified Party shall have been advised by counsel that a conflict of interest is likely to exist if the same counsel were to represent such Indemnified Party and the Indemnifying Party (in which case, if such Indemnified Party notifies the Indemnifying Party in writing that it elects to employ separate counsel at the expense of the Indemnifying Party, the Indemnifying Party shall not have the right to assume the defense thereof and such counsel shall be at the expense of the Indemnifying Party); provided, that the Indemnifying Party shall not be liable for the fees and expenses of more than one separate firm of attorneys at any time for all Indemnified Parties pursuant to this Section 5(c). The Indemnifying Party shall not be liable for any settlement of any such Proceeding effected without its written consent, which consent shall not be unreasonably withheld. No Indemnifying Party shall, without the prior written consent of the Indemnified Party, effect any settlement of any pending Proceeding in respect of which

11

any Indemnified Party is a party, unless such settlement includes an unconditional release of such Indemnified Party from all liability on claims that are the subject matter of such Proceeding.

(iii)      All fees and expenses of the Indemnified Party (including reasonable fees and expenses to the extent incurred in connection with investigating or preparing to defend such Proceeding in a manner not inconsistent with this Section) shall be paid to the Indemnified Party, as incurred, within ten Trading Days of written notice thereof to the Indemnifying Party (regardless of whether it is ultimately determined that an Indemnified Party is not entitled to indemnification hereunder; provided, that the Indemnifying Party may require such Indemnified Party to undertake to reimburse all such fees and expenses to the extent it is finally judicially determined that such Indemnified Party is not entitled to indemnification hereunder).

(d)                     Contribution.

(i)        If a claim for indemnification under Section 5(a) or 5(b) is unavailable to an Indemnified Party (by reason of public policy or otherwise), then each Indemnifying Party, in lieu of indemnifying such Indemnified Party, shall contribute to the amount paid or payable by such Indemnified Party as a result of such Losses, in such proportion as is appropriate to reflect the relative fault of the Indemnifying Party and Indemnified Party in connection with the actions, statements or omissions that resulted in such Losses as well as any other relevant equitable considerations. The relative fault of such Indemnifying Party and Indemnified Party shall be determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement of a material fact or omission or alleged omission of a material fact, has been taken or made by, or relates to information supplied by, such Indemnifying Party or Indemnified Party, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such action, statement or omission. The amount paid or payable by a party as a result of any Losses shall be deemed to include, subject to the limitations set forth in Section 5(c), any reasonable attorneys’ or other reasonable fees or expenses incurred by such party in connection with any Proceeding to the extent such party would have been indemnified for such fees or expenses if the indemnification provided for in this Section was available to such party in accordance with its terms.

(ii)       The parties hereto agree that it would not be just and equitable if contribution pursuant to this Section 5(d) were determined by pro rata allocation or by any other method of allocation that does not take into account the equitable considerations referred to in the immediately preceding paragraph. Notwithstanding the provisions of this Section 5(d), no Holder shall be required to contribute, in the aggregate, any amount in excess of the amount by which the proceeds actually received by such Holder from the sale of the Registrable Securities subject to the Proceeding exceeds the amount of any damages that such Holder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of

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such fraudulent misrepresentation.

(iii)      The indemnity and contribution agreements contained in this Section are in addition to any liability that the Indemnifying Parties may have to the Indemnified Parties and are not in diminution or limitation of the indemnification provisions under the Purchase Agreement.

6.  Miscellaneous.

(a)       Remedies.  In addition to being entitled to exercise all rights provided herein or granted by law, including recovery of damages, each Holder will be entitled to seek specific performance under this Agreement.  The parties agree that monetary damages may not be adequate compensation for any loss incurred by reason of any breach of the Company’s obligations contained in this Agreement and the Company hereby agrees to waive and not to assert in any action for specific performance of any such obligation the defense that a remedy at law would be adequate.

(b)       Reports.  With a view to making available to the Holders the benefits of Rule 144 or any other similar rule or regulation of the Commission that may at any time permit the Holders to sell securities of the Company to the public without registration, the Company agrees, from the date hereof until the end of the Effectiveness Period, to (i) make and keep current public information available, as those terms are understood and defined in Rule 144; (ii) file with the Commission in a timely manner all reports and other documents required of the Company under the Securities Act and the Exchange Act; and (iii) furnish to each Holder so long as such Holder owns Registrable Securities, promptly upon request, (A) a written statement by the Company, if true, that it has complied with the reporting requirements of Rule 144, the Securities Act and the Exchange Act, (B) a copy of the most recent annual or quarterly report of the Company and such other reports and documents so filed by the Company, and (C) such other information as may be reasonably requested to permit the Holders to sell such securities pursuant to Rule 144 without registration.

(c)       Subsequent Registration Rights.  Until the Initial Registration Statement required hereunder is declared effective by the Commission, the Company shall not enter into any agreement granting any registration rights with respect to any of its securities to any Person without the written consent of the Purchaser, for so long as the Purchaser or its assignee holds any Registrable Securities.

(d)       Discontinued Disposition.  Each Holder agrees by its acquisition of such Registrable Securities that, upon receipt of a notice from the Company of the occurrence of any event of the kind described in clauses (ii) through (vi) of Section 3(c), such Holder will forthwith discontinue disposition of such Registrable Securities under the Registration Statement until such Holder’s receipt of the copies of the supplemented Prospectus and/or amended Registration Statement or until it is advised in writing by the Company that the use of the applicable Prospectus may be resumed, and, in either case, has received copies of any additional or supplemental filings that are incorporated or deemed to be incorporated by reference in such Prospectus or Registration Statement. The Company acknowledges that receipt of such notice

13

shall not require the Holders to cease to sell any Registrable Securities other than pursuant to the Registration Statement and that the Holders may at any time without restriction sell Registrable Securities other than pursuant to the Registration Statement.

(e)       Furnishing of Information.  Each Holder shall furnish in writing to the Company such information regarding itself, the Registrable Securities held by it and the intended method of disposition of the Registrable Securities held by it, as shall be reasonably requested by the Company to effect the registration of such Registrable Securities and shall execute such documents in connection with such registration as the Company may reasonably request.

(f)        Piggy-Back Registrations. If at any time during the Effectiveness Period, except as contemplated by Section 2(b) or Section 2(d) hereof, there is not an effective Registration Statement covering all of the Registrable Securities and the Company shall determine to prepare and file with the Commission a registration statement relating to an offering for its own account or the account of others under the Securities Act of any of its equity securities, other than on Form S-4 or Form S-8 (each as promulgated under the Securities Act) or their then equivalents relating to equity securities to be issued solely in connection with any acquisition of any entity or business or equity securities issuable in connection with the stock option or other employee benefit plans, then the Company shall send to each Holder a written notice of such determination and, if within 15 days after the date of such notice, any such Holder shall so request in writing, the Company shall include in such registration statement all or any part of such Registrable Securities such Holder requests to be registered.

(g)       Amendments and Waivers.  No provision of this Agreement may be waived or amended except in a written instrument signed by the Company and the Purchaser, for so long as the Purchaser holds any Registrable Securities, and thereafter by the Holder(s) of a majority of the then outstanding Registrable Securities. Any amendment or waiver effected in accordance with this Section 6(g) shall be binding upon each Holder and the Company. No waiver of any default with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing waiver in the future or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay or omission of either party to exercise any right hereunder in any manner impair the exercise of any such right.

(h)       Notices.  Any and all notices or other communications or deliveries required or permitted to be provided hereunder shall be in writing and shall be deemed given and effective on the earliest of (a) the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number set forth on the signature pages attached hereto prior to 5:30 p.m. (New York City time) on a Trading Day, (b) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number set forth on the signature pages attached hereto on a day that is not a Trading Day or later than 5:30 p.m. (New York City time) on any Trading Day, (c) the 2nd Trading Day following the date of mailing, if sent by U.S. nationally recognized overnight courier service, or (d) upon actual receipt by the party to whom such notice is required to be given.  The addresses for such notices and communications shall be as follows:

If to the Company:

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ImmunoGen, Inc.

830 Winter Street

Waltham, MA 02451

Fax:  (781) 895-0613

Attn:  General Counsel

with a copy (which shall not constitute notice) to:

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
One Financial Center
Boston, MA 02111
Fax:  (617) 542-2241

Attn:  Jonathan L. Kravetz, Esq

If to the Purchaser:

Ziff Brothers Investments
350 Park Avenue
New York, NY  10022
Attention:  General Counsel
Fax:  (212) 292-6659

with a copy (which shall not constitute notice) to:

Fried, Frank, Harris, Shriver & Jacobson LLP
One New York Plaza
New York, New York 10004
Attention:  Jonathan Adler, Esq.

Fax:  (212) 859-4000

If to a Holder (other than the Purchaser), to such Holder’s address and facsimile number set forth in the agreement pursuant to which such Holder agrees to be bound by the provisions of this Agreement in accordance with Section 6(h);

or such other address as may be designated in writing hereafter, in the same manner, by such Person.

(i)        Successors and Assigns.  This Agreement shall inure to the benefit of and be binding upon the successors and permitted assigns of each of the parties and shall inure to the benefit of each Holder.  The Company may not assign its obligations under this Agreement.  Each Holder may assign any or all of its respective rights under this Agreement to any transferee of all or any portion of such Holder’s Registrable Securities provided the transferee or assignee agrees to be bound by all of the provisions contained herein.  Each Holder shall, no later than 10 days following any transfer, give written notice (which shall include the identity of the transferee) to the Company of any transfer by it of Registrable Securities that remain Registrable Securities following such transfer.

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(j)        Execution and Counterparts.  This Agreement may be executed in two or more counterparts, all of which when taken together shall be considered one and the same agreement and shall become effective when counterparts have been signed by each party and delivered to the other party, it being understood that both parties need not sign the same counterpart.  In the event that any signature is delivered by facsimile transmission or by e-mail delivery of a “.pdf” format data file, such signature shall create a valid and binding obligation of the party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf” signature page were an original thereof.

(k)       Governing Law.  All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be governed by and construed and enforced in accordance with the internal laws of the State of New York, without regard to the principles of conflicts of law thereof.  Each party agrees that all legal proceedings concerning the interpretations, enforcement and defense of the transactions contemplated by this Agreement (whether brought against a party hereto or its respective affiliates, directors, officers, shareholders, employees or agents) shall be commenced exclusively in the state and federal courts sitting in the City of New York.  Each party hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of New York, borough of Manhattan for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein, and hereby irrevocably waives, and agrees not to assert in any suit, action or proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such suit, action or proceeding is improper or is an inconvenient venue for such proceeding.  Each party hereby irrevocably waives personal service of process and consents to process being served in any such suit, action or proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Agreement and agrees that such service shall constitute good and sufficient service of process and notice thereof.  Nothing contained herein shall be deemed to limit in any way any right to serve process in any other manner permitted by law.  If either party shall commence an action or proceeding to enforce any provisions of this Agreement, then the prevailing party in such action or proceeding shall be reimbursed by the other party for its reasonable attorneys’ fees and other costs and expenses incurred with the investigation, preparation and prosecution of such action or proceeding.

(l)        Cumulative Remedies.  The remedies provided herein are cumulative and not exclusive of any remedies provided by law.

(m)      Severability.  If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction to be invalid, illegal, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions set forth herein shall remain in full force and effect and shall in no way be affected, impaired or invalidated, and the parties hereto shall use their commercially reasonable efforts to find and employ an alternative means to achieve the same or substantially the same result as that contemplated by such term, provision, covenant or restriction.  It is hereby stipulated and declared to be the intention of the parties that they would have executed the remaining terms, provisions, covenants and restrictions without including any of such that may be hereafter declared invalid, illegal, void or unenforceable.

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(n)       Actions by Holders.  All consents and other determinations required to be made by the Holders pursuant to this Agreement shall be made, unless otherwise specified in this Agreement, by the Purchaser, for so long as the Purchaser holds any Registrable Securities, and thereafter by the Holder(s) of a majority of the then outstanding Registrable Securities.

(o)       Headings.  The headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning hereof.

[Signature Page Follows]

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement as of the date first written above.

[Signature Page to Registration Rights Agreement]

ANNEX A

PLAN OF DISTRIBUTION

We are registering the shares on behalf of the selling stockholder.  The selling stockholder and any of its transferees who are affiliates, or any of its pledgees, assignees and successors-in-interest may, from time to time, sell any or all of its shares of Common Stock or any interests therein on any stock exchange, market or trading facility on which the shares are traded or in private transactions.  These sales may be at market prices prevailing at the time of sale, at prices related to the prevailing market prices or at fixed or negotiated prices, or varying prices determined at the time of sale.  The shares of Common Stock may be sold by the selling stockholder directly to one or more purchasers, through agents designated from time to time or to or through one or more underwriters or broker-dealers designated from time to time. In the event the shares of Common Stock are publicly offered through broker-dealers or agents, the selling stockholder may enter into agreements with respect thereto.  The selling stockholder may also transfer, devise or gift these shares by other means not described in this prospectus.  The selling stockholder may also use any one or more of the following methods when selling shares:

·                  on any national securities exchange or quotation service on which the securities may be listed or quoted at the time of sale or in private transactions;

·                  in the over-the-counter market;

·                  in transactions otherwise than on these exchanges or systems or in the over-the-counter market;

·                  ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;

·                  block trades in which the broker-dealer will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;

·                  purchases by a broker-dealer as principal and resale by the broker-dealer for its account;

·                  an exchange distribution in accordance with the rules of the applicable exchange;

·                  privately negotiated transactions;

·                  short sales;

·                  broker-dealers may agree with the selling stockholder to sell a specified number of such shares at a stipulated price per share;

·                  through the writing or settlement of options or other hedging transactions entered into after the effective date of the registration statement of which this prospectus is a part,

i

whether through an options exchange or otherwise;

·                  a combination of any such methods of sale; or

·                  any other method permitted pursuant to applicable law.

The selling stockholder may also sell shares under Rule 144 under the Securities Act, if available, rather than under this prospectus, provided it meets the criteria and conforms to the requirements of such Rule.

In connection with the sale of the Common Stock or interests therein, the selling stockholder may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the Common Stock in the course of hedging the positions they assume.  The selling stockholder may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of shares offered by this prospectus, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented to reflect such transaction). The selling stockholder may also engage in short sales against the box, puts and calls, loans or pledges and other transactions in securities of the Company or derivatives of Company securities and may sell or deliver shares in connection with these trades.

Broker-dealers engaged by the selling stockholder may arrange for other broker-dealers to participate in sales.  Broker-dealers may receive commissions or discounts from the selling stockholder (or, if any broker-dealer acts as agent for the purchaser of shares, from the purchaser) in amounts to be negotiated.  The selling stockholder does not expect these commissions and discounts to exceed what is customary in the types of transactions involved. Discounts, commissions and similar selling expenses, if any, will be borne by the selling stockholder.

The selling stockholder may from time to time pledge or grant a security interest in some or all of the shares of Common Stock owned by it, and, if it defaults in the performance of its secured obligations, the pledgees or secured parties may offer and sell the shares of Common Stock from time to time under this prospectus, or under an amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act amending, if necessary, the list of selling stockholders to include the pledgee, transferee or other successors in interest as selling stockholders under this prospectus.

The selling stockholder may also transfer shares of Common Stock in other circumstances, in which case, upon notification of such transfer, we will file, to the extent required, a supplement to this prospectus disclosing all required information and the transferees, pledgees, assignees and successors-in-interest will be the selling beneficial owner for purposes of this prospectus and may sell the shares of Common Stock from time to time under this prospectus.

The selling stockholder and any broker-dealers or agents that are involved in selling the shares may be deemed to be “underwriters” within the meaning of Section 2(11) of the Securities

ii

Act in connection with such sales.  In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act.  The maximum commission or discount to be received by any member of the Financial Industry Regulatory Authority (FINRA) or independent broker-dealer will not be greater than 8% of the initial gross proceeds from the sale of any security being sold.

We have agreed to indemnify the selling stockholder against certain liabilities, including liabilities arising under the Securities Act.  The selling stockholder may agree to indemnify any agent, dealer or broker-dealer that participates in transactions involving sales of the shares against certain liabilities, including liabilities arising under the Securities Act.

Because the selling stockholder may be deemed to be an “underwriter” within the meaning of Section 2(11) of the Securities Act, the selling stockholder will be subject to the prospectus delivery requirements of the Securities Act, which may include delivery through the facilities of Nasdaq. The Company has informed the selling stockholder that the anti-manipulative provisions of Regulation M promulgated under the Exchange Act may apply to its sales in the market.

The selling stockholder has advised us that, as of the date of this prospectus, it has not entered into any agreements, understandings or arrangements with any underwriters or broker-dealers regarding the sale of its securities, nor is there an underwriter or coordinating broker acting in connection with the proposed sale of shares by the selling stockholder.  However, the selling stockholder may enter into agreements, understandings or arrangements with underwriters or broker-dealers regarding the sale of its securities and upon notification by the selling stockholder that any material arrangement has been entered into with a broker-dealer or underwriter for the sale of shares through a block trade, special offering, exchange distribution or secondary distribution or a purchase by a broker or dealer, we will file a supplement to this prospectus, if required, disclosing all required information.  In addition, upon notification by the selling stockholder that a donee or pledgee intends to sell more than 500 shares, we will file a supplement to this prospectus.

The aggregate proceeds to the selling stockholder from the sale of the Common Stock offered by the selling stockholder will be the purchase price of the Common Stock less discounts or commissions, if any. The selling stockholder reserves the right to accept and, together with its agents from time to time, to reject, in whole or in part, any proposed purchase of Common Stock to be made directly or through agents. We will not receive any of the proceeds from this offering.

We will pay all fees and expenses incident to the registration of the shares, including up to $25,000 of the fees and disbursements of counsel to the selling stockholder.

We have agreed with the selling stockholder to keep the registration statement of which this prospectus constitutes a part effective until the earlier to occur of (x) such time as all of the shares covered by this prospectus have been disposed of pursuant to the registration statement  or pursuant to Rule 144 under the Securities Act, or (y) following any sale (other than pursuant to the registration statement or Rule 144) of such shares by the selling stockholder to any person (other than an affiliate of the selling stockholder) who, after giving effect to such sale, owns less

iii

than 10% of our outstanding shares of Common Stock, at such time as such person is able to sell all of his or its shares pursuant to Rule 144(b)(1).

iv

Exhibit 99.1

Contact:

For Immediate Release

ImmunoGen, Inc. Raises $25.0 Million

in Registered Direct Offering of Common Stock

WALTHAM, MA, June 23, 2008 – ImmunoGen, Inc. (Nasdaq: IMGN), a biopharmaceutical company that develops targeted anticancer therapeutics, today announced that Ziff Asset Management, L.P. has purchased approximately 7.8 million shares of ImmunoGen’s common stock at $3.20 per share. The shares were offered by ImmunoGen pursuant to an effective shelf registration statement previously filed with the Securities and Exchange Commission. Proceeds to ImmunoGen from the offering, net of estimated expenses, are expected to be approximately $24.7 million.

Copies of the final prospectus supplement and accompanying prospectus relating to this offering may be obtained by writing the Investor Relations department of ImmunoGen, Inc., 830 Winter Street, Waltham, MA 02451, or by calling (781) 895-0600.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer biopharmaceuticals. The Company’s proprietary Tumor-Activated Prodrug (TAP) technology uses tumor-targeting antibodies to deliver a potent cell-killing agent specifically to cancer cells. Two TAP compounds wholly owned by ImmunoGen are in clinical testing – IMGN901 and IMGN242. Three TAP compounds are in clinical testing through ImmunoGen’s collaborations with other companies – AVE9633 and SAR3419, in development by sanofi-aventis, and trastuzumab-DM1 (T-DM1), in development by Genentech. AVE1642, a naked antibody, also is in clinical testing through the Company’s collaboration with sanofi-aventis. Multiple compounds are advancing towards the clinic through the ImmunoGen’s collaborations and internal programs.

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