WARRANT AGENT AGREEMENT

Exhibit 4.1

SIPEX CORPORATION

and

WELLS FARGO BANK, NATIONAL ASSOCIATION,

as Warrant Agent

WARRANT AGENT AGREEMENT

Dated as of May 16, 2006

WARRANT AGENT AGREEMENT

TABLE OF CONTENTS

WARRANT AGENT AGREEMENT (“Warrant Agent Agreement”) dated as of May 16, 2006 between Sipex Corporation, a Delaware corporation (the “Company”), and Wells Fargo Bank, National Association, a national banking association organized and in good standing under the laws of the United States, as Warrant Agent (the “Warrant Agent”).

WHEREAS, the Company has entered into a Securities Purchase Agreement dated May 16, 2006 (the “Securities Purchase Agreement”) by and between the Company and the buyers listed in Exhibit A to the Securities Purchase Agreement pursuant to which the Company proposes to issue warrants to purchase common stock of the Company, as hereinafter described (the “Warrants”), which in the aggregate initially entitle the holders thereof to purchase 1,679,104 shares of Common Stock of the Company (the “Common Stock” and with the Common Stock issuable on exercise of the Warrants being referred to herein as the “Warrant Shares”). Capitalized terms used and not otherwise defined herein have the meanings ascribed thereto in the Warrant Certificate (as defined below).

WHEREAS, the Company desires the Warrant Agent to act on behalf of the Company, and the Warrant Agent is willing so to act, in connection with the transfer, exchange and exercise of Warrants and other matters as provided herein;

NOW, THEREFORE, in consideration of the premises and the mutual agreements herein set forth, the parties hereto agree as follows:

SECTION 1. Appointment of Warrant Agent . The Company hereby appoints the Warrant Agent to act as agent for the Company in accordance with the instructions set forth hereinafter in this Agreement, and the Warrant Agent hereby accepts such appointment. The Company may from time to time appoint such Co-Warrant Agent(s) as it may deem necessary or desirable upon ten (10) days’ prior written notice to the Warrant Agent. The Warrant Agent shall have no duty to supervise, and shall in no event be liable for, the acts or omissions of any such Co-Warrant Agent(s).

SECTION 2. Warrant Certificates . The certificates evidencing the Warrants (the “Warrant Certificates”) to be delivered pursuant to this Agreement shall be in registered form only and shall be substantially in the form set forth in Exhibit A attached hereto. The Warrant Certificates are hereby made a part of this Agreement and the terms and conditions set forth therein are hereby incorporated herein.

SECTION 3. Execution of Warrant Certificates . Warrant Certificates shall be signed on behalf of the Company by its Chairman of the Board, Chief Executive Officer, Chief Financial Officer, President or a Vice President. Each such signature upon the Warrant Certificates may be in the form of a facsimile signature of the present or any future Chairman of the Board, Chief Executive Officer, Chief Financial Officer, President, or a Vice President and may be imprinted or otherwise reproduced on the Warrant Certificates and for that purpose the Company may adopt and use the facsimile signature of any person who shall have been Chairman of the Board, Chief Executive Officer, Chief Financial Officer, President, or a Vice President, notwithstanding the fact that at the time the Warrant Certificates shall be transferred or disposed of he or she shall have ceased to hold such office.

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In case any officer of the Company who shall have signed any of the Warrant Certificates shall cease to be such officer before the Warrant Certificates so signed shall be transferred or disposed of by the Company, such Warrant Certificates nevertheless may be transferred or disposed of as though such person had not ceased to be such officer of the Company; and any Warrant Certificate may be signed on behalf of the Company by any person who, at the actual date of the execution of such Warrant Certificate, shall be a proper officer of the Company to sign such Warrant Certificate, although at the date of the execution of this Warrant Agent Agreement any such person was not such officer.

Each Warrant Certificate shall be dated the date such Warrant Certificate was authorized to be transferred by the Company.

SECTION 4. Registration . The Warrant Agent, on behalf of the Company, shall hold any unregistered Warrants.

The Company and the Warrant Agent may deem and treat the registered holder(s) of the Warrant Certificates as the absolute owner(s) thereof (notwithstanding any notation of ownership or other writing thereon made by anyone), for all purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.

SECTION 5. Registration of Transfers and Exchanges . The Warrant Agent shall from time to time, subject to the limitations and on the terms and conditions set forth in the Warrant Certificates, register the transfer of any outstanding Warrant Certificates upon the records to be maintained by it for that purpose, upon surrender thereof duly endorsed or accompanied (if so required by the Company) by a written instrument or instruments of transfer in form satisfactory to the Company, duly executed by the registered holder or holders thereof or by the duly appointed legal representative thereof or by a duly authorized attorney. Upon any such registration of transfer, a new Warrant Certificate shall be issued to the transferee(s) and the surrendered Warrant Certificate shall be cancelled by the Warrant Agent. Cancelled Warrant Certificates shall thereafter be disposed of by the Warrant Agent in its customary manner.

Subject to the terms of the Warrant Certificates, Warrant Certificates may be exchanged at the option of the holder(s) thereof, when surrendered to the Warrant Agent at its principal corporate trust office, which is currently located at the address listed in Section 12 hereof, for another Warrant Certificate or other Warrant Certificates of like tenor and representing in the aggregate a like number of Warrants. Any holder desiring to exchange a Warrant Certificate shall deliver a written request to the Warrant Agent, and shall surrender, duly endorsed or accompanied (if so required by the Warrant Agent) by a written instrument or instruments of transfer in form satisfactory to the Warrant Agent, the Warrant Certificate or Certificates to be so exchanged. Warrant Certificates surrendered for exchange shall be cancelled by the Warrant Agent. Such cancelled Warrant Certificates shall then be disposed of by such Warrant Agent in its customary manner.

The Warrant Agent is hereby authorized to transfer, in accordance with the provisions of this Section 5, the new Warrant Certificates required pursuant to the provisions of this Section 5.

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SECTION 6. Terms and Exercise of Warrants . A Warrant may be exercised, subject to the terms and conditions therein, upon surrender to the Company at the principal corporate trust office of the Warrant Agent, which is currently located at the address listed in Section 12 hereof.

The Warrant Agent may assume that any Warrant presented for exercise is permitted to be so exercised under applicable law and shall have no liability for acting in reliance on such assumption. All Warrant Certificates surrendered upon exercise of Warrants shall be canceled by the Warrant Agent. Such canceled Warrant Certificates shall then be disposed of by the Warrant Agent in its customary manner. The Warrant Agent shall account promptly to the Company with respect to Warrants exercised and concurrently pay to the Company all monies received by the Warrant Agent for the purchase of the Warrant Shares through the exercise of such Warrants to the extent such Warrant is not exercised as a Cashless Exercise by the holder of the Warrant pursuant to Section 2(e) of the Warrant.

The Warrant Agent shall keep copies of this Agreement and any notices given or received hereunder available for inspection by the holders with reasonable prior written notice during normal business hours at its corporate trust office, which is currently located at the address listed in Section 12 hereof.

SECTION 7. Reservation of Warrant Shares . The Warrant Agent shall have no duty to verify availability of any shares of Common Stock set aside pursuant to Section 4(b) of the Warrant Certificates. The Company will keep a copy of this Agreement on file with the Transfer Agent (used hereinafter as such term is defined in the Warrant Certificates) and with every subsequent transfer agent for any shares of the Company’s Common Stock issuable upon the exercise of the rights of purchase represented by the Warrants. The Warrant Agent is hereby irrevocably authorized to requisition from time to time from such Transfer Agent the stock certificates required to honor outstanding Warrants upon exercise thereof in accordance with the terms of this Agreement. The Company will supply such Transfer Agent with duly executed certificates for such purposes and will provide or otherwise make available any cash which may be payable as provided in Section 2 of the Warrant Certificates. The Company will furnish such Transfer Agent a copy of all notices filed with the Warrant Agent pursuant to Section 8 hereof.

SECTION 8. Notices to Warrant Agent . The Company shall cause to be filed with the Warrant Agent a copy of every notice or other communication sent to the registered holders of the Warrant Certificates pursuant to the Warrant Certificates promptly upon delivery of any such notice or communication to the registered holders of the Warrant Certificates.

SECTION 9. Merger, Consolidation or Change of Name of Warrant Agent . Any corporation into which the Warrant Agent may be merged or with which it may be consolidated, or any corporation resulting from any merger or consolidation to which the Warrant Agent shall be a party, or any corporation succeeding to all or substantially all the corporate trust or agency business of the Warrant Agent, shall be the successor to the Warrant Agent hereunder without the execution or filing of any paper or any further act on the part of any of the parties hereto, provided that such corporation would be eligible for appointment as a successor warrant agent under the provisions of Section 11 of this Agreement.

SECTION 10. Warrant Agent . The Warrant Agent undertakes the duties and obligations imposed by this Agreement (and no implied duties or obligations shall be read into this

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Agreement against the Warrant Agent) upon the following terms and conditions, all of which the Company and the holders of Warrants, by their acceptance thereof, shall be bound:

(a) the Warrant Agent may conclusively rely and shall be protected in acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, bond, note, coupon or other paper or document believed by it in good faith to be genuine and to have been signed or presented by the proper party or parties;

(b) any request, direction, order or demand of the Company mentioned herein shall be sufficiently evidenced by a certificate from the Company (unless other evidence in respect thereof be herein specifically prescribed);

(c) the Warrant Agent may consult with counsel of its selection, and any advice of such counsel or opinion of counsel as to matters of law shall be full and complete authorization and protection in respect of any action taken or omitted by it hereunder in good faith and in accordance with such advice or opinion of counsel if such counsel was selected with due care;

(d) the Warrant Agent shall be under no obligation to exercise any of the rights or powers vested in it by this Warrant Agreement at the request, order or direction of any of the holders of Warrant Certificates pursuant to the provisions of this Warrant Agent Agreement, unless such holders of Warrant Certificates shall have offered to the Warrant Agent security or indemnity reasonably satisfactory to it against the costs, expenses and liabilities which may be incurred therein or thereby;

(e) the Warrant Agent shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, bond, debenture or other paper or document, but the Warrant Agent, in its reasonable discretion, may make such further inquiry or investigation into such facts or matters as it may see fit, and, if the Warrant Agent shall determine to make such further inquiry or investigation, it shall be entitled to examine the books, records and premises of the Company, personally or by agent or attorney; provided , however , that if the payment within a reasonable time to the Warrant Agent of the costs, expenses or liabilities likely to be incurred by it in the making of such investigation is, in the opinion of the Warrant Agent, not reasonably assured to the Warrant Agent by the security afforded to it by the terms of this Warrant Agent Agreement, the Warrant Agent may require indemnity reasonably satisfactory to the Warrant Agent from the holders of Warrant Certificates against such expenses or liability as a condition to so proceeding; the reasonable expenses of every such examination shall be paid by the Company or, if paid by the Warrant Agent or any predecessor Warrant Agent, shall be repaid by the Company upon demand;

(f) the Warrant Agent may execute any of the powers hereunder or perform any duties hereunder either directly or by or through agents or attorneys and the Warrant Agent shall not be responsible for any misconduct or negligence on the part of any agent or attorney appointed by it with due care hereunder;

(g) the Warrant Agent shall not be liable for any action taken, suffered, or omitted to be taken by it in good faith and reasonably believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Warrant Agent Agreement;

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(h) the rights, privileges, protections, immunities and benefits given to the Warrant Agent, including, without limitation, its right to be indemnified, are extended to, and shall be enforceable by, the Warrant Agent in each of its capacities hereunder, and to each agent, custodian and other person employed to act hereunder;

(i) the Warrant Agent may request that the Company deliver a certificate of the Company setting forth the names of individuals and/or titles of officers authorized at such time to take specified actions pursuant to this Warrant Agent Agreement, which such certificate may be signed by any person authorized to sign an such certificate, including any person specified as so authorized in any such certificate previously delivered and not superseded; and

(j) the Warrant Agent shall not at any time be under any duty or responsibility to any holder of any Warrant Certificate to make or cause to be made any adjustment of the Exercise Price or number of the Warrant Shares or other securities or property deliverable as provided in this Agreement, or to determine whether any facts exist which may require any of such adjustments, or with respect to the nature or extent of any such adjustments, when made, or with respect to the method employed in making the same. The Warrant Agent shall not be accountable with respect to the validity or value or the kind or amount of any Warrant Shares or of any securities or property which may at any time be issued or delivered upon the exercise of any Warrant or with respect to whether any such Warrant Shares or other securities will when issued be validly issued and fully paid and nonassessable, and makes no representation with respect thereto.

SECTION 11. Change of Warrant Agent . The Warrant Agent may at any time resign as Warrant Agent upon written notice to the Company. If the Warrant Agent shall resign or become incapable of acting as Warrant Agent, the Company shall appoint a successor to such Warrant Agent. If the Company shall fail to make such appointment within a period of thirty (30) days after it has been notified in writing of such resignation or of such incapacity by the Warrant Agent or by the registered holder of a Warrant Certificate, then the registered holder of any Warrant Certificate or the Warrant Agent may apply, at the expense of the Company, to any court of competent jurisdiction for the appointment of a successor to the Warrant Agent. Pending appointment of a successor to such Warrant Agent, either by the Company or by such a court, the duties of the Warrant Agent shall be carried out by the Company. The holders of a majority of the unexercised Warrants shall be entitled at any time to remove the Warrant Agent and appoint a successor to such Warrant Agent. If a Successor Warrant Agent shall not have been appointed within thirty (30) days of such removal, the Company may appoint a successor to such Warrant Agent. If the Company shall fail to make such appointment within a period of thirty (30) days after the expiration of the thirty (30) day period during which the holders of a majority of the unexercised Warrants could appoint a successor Warrant Agent, then the registered holder of any Warrant Certificate or the Warrant Agent may apply, at the expense of the Company, to any court of competent jurisdiction for the appointment of a successor to the Warrant Agent. Such successor to the Warrant Agent need not be approved by the Company or the former Warrant Agent. After appointment the successor to the Warrant Agent shall be vested with the same powers, rights, duties and responsibilities as if it had been originally named as Warrant Agent without further act or deed; but the former Warrant Agent, upon payment of all fees and expenses due it and its agents and counsel, shall deliver and transfer to the successor to the Warrant Agent any property at the time held by it hereunder and execute and deliver any further

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assurance, conveyance, act or deed necessary for the purpose. Failure to give any notice provided for in this Section 11, however, or any defect therein, shall not affect the legality or validity of the appointment of a successor to the Warrant Agent.

SECTION 12. Notices to Company and Warrant Agent . Any notice or demand authorized by this Agreement to be given or made by the Warrant Agent or by the registered holder of any Warrant Certificate to or on the Company shall be sufficiently given or made when and if deposited in the mail, first class or registered, postage prepaid, addressed (until another address is filed in writing by the Company with the Warrant Agent), as follows:

In case the Company shall fail to maintain such office or agency or shall fail to give such notice of the location or of any change in the location thereof, presentations may be made and notices and demands may be served at the principal corporate trust office of the Warrant Agent.

Any notice pursuant to this Agreement to be given by the Company or by the registered holder(s) of any Warrant Certificate to the Warrant Agent shall be sufficiently given when and if deposited in the mail, first-class or registered, postage prepaid, addressed (until another address is filed in writing by the Warrant Agent with the Company) to the Warrant Agent as follows:

Well Fargo Bank, National Association

707 Wilshire Blvd., 17 ^th Floor

Los Angeles, CA 90017

Attention: Corporate Trust Services

Fax: (213) 614-3355

SECTION 13. Supplements and Amendments . The Company and the Warrant Agent may from time to time supplement or amend this Agreement without the approval of any holders of Warrant Certificates in order to cure any ambiguity or to correct or supplement any provision contained herein which may be defective or inconsistent with any other provision herein, or to make any other provisions in regard to matters or questions arising hereunder which the Company and the Warrant Agent may deem necessary or desirable and which shall not in any way adversely affect the interests of the holders of Warrant Certificates. Upon the delivery of a certificate from an appropriate officer of the Company which states that the proposed supplement or amendment is in compliance with the terms of this Section 13, the Warrant Agent shall execute such supplement or amendment. Notwithstanding anything in this Agreement to the contrary, the prior written consent of the Warrant Agent must be obtained in connection with any

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supplement or amendment which alters the rights or duties of the Warrant Agent. The Company and the Warrant Agent may amend any provision herein with the consent of the holders of a majority of the unexercised Warrants.

SECTION 14. Successors . All the covenants and provisions of this Agreement by or for the benefit of the Company or the Warrant Agent shall bind and inure to the benefit of their respective successors and assigns hereunder.

SECTION 15. Termination . This Agreement will terminate on any earlier date if all Warrants have been exercised or expired without exercise. The provisions of Section 10 hereof shall survive such termination.

SECTION 16. Governing Law and Jurisdiction . This Agreement and each Warrant Certificate issued hereunder shall be deemed to be a contract made under the laws of the State of New York and for all purposes shall be construed in accordance with the internal laws of the State of New York without giving effect to any choice of law or conflict of law provision or rule (whether of the State of New York or any other jurisdictions) that would cause the application of the laws of any jurisdictions other than the State of New York. Each party hereby irrevocably submits to the non-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 brought in an inconvenient forum or that the venue of such suit, action or proceeding is improper. 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 to such party at the address for such 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 manner permitted by law. If any provision of this Agreement shall be invalid or unenforceable in any jurisdiction, such invalidity or unenforceability shall not affect the validity or enforceability of the remainder of this Agreement in that jurisdiction or the validity or enforceability of any provision of this Agreement in any other jurisdiction. EACH PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN CONNECTION HEREWITH OR ARISING OUT OF THIS AGREEMENT OR ANY TRANSACTION CONTEMPLATED HEREBY.

SECTION 17. Benefits of This Agreement . Nothing in this Agreement shall be construed to give to any person or corporation other than the Company, the Warrant Agent and the registered holders of the Warrant Certificates any legal or equitable right, remedy or claim under this Agreement, and this Agreement shall be for the sole and exclusive benefit of the Company, the Warrant Agent and the registered holders of the Warrant Certificates.

SECTION 18. Counterparts . This Agreement may be executed in any number of counterparts and each of such counterparts shall for all purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument.

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SECTION 19. Conflicting Terms . In the event of any inconsistency or conflict between the Warrants and this Agreement, the terms, conditions and provisions of the Warrants shall govern and control.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed, as of the day and year first above written.

SIPEX CORPORATION

WELLS FARGO BANK, NATIONAL ASSOCIATION,

as Warrant Agent

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EXHIBIT A TO WARRANT AGENT AGREEMENT

FORM OF WARRANT

[THE FOLLOWING PARAGRAPH SHALL APPEAR ON THE FACE OF EACH RESTRICTED WARRANT:]

THE SECURITIES REPRESENTED BY THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED OR APPLICABLE STATE SECURITIES LAWS. THE SECURITIES MAY NOT BE OFFERED FOR SALE, SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED OR APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION FROM THE SECURITIES ACT OR APPLICABLE STATE SECURITIES LAWS. THE SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN SECURED BY THE SECURITIES.

[THE COMPANY MAY PLACE THE FOLLOWING PARAGRAPH ON THE FACE OF EACH WARRANT HELD BY OR TRANSFERRED TO AN “AFFILIATE” (AS DEFINED IN RULE 501(B) OF REGULATION D UNDER THE SECURITIES ACT) OF THE COMPANY:]

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THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE HELD BY A PERSON WHO MAY BE DEEMED TO BE AN AFFILIATE OF THE ISSUER FOR PURPOSES OF RULE 144 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND MAY BE SOLD ONLY IN COMPLIANCE WITH RULE 144 OR PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT.

SIPEX CORPORATION

WARRANT TO PURCHASE COMMON STOCK

Warrant No.: [              ] Number of Shares: [              ]

CUSIP No.: [              ] (subject to adjustment)

Date of Issuance:          May , 2006

Sipex Corporation, a Delaware corporation (the “Company”), hereby certifies that, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged,          , the registered holder hereof or its permitted assigns is entitled, subject to the terms and conditions set forth below, to purchase from the Company upon surrender of this Warrant (as defined below), at any time or times on or after the date hereof, but not after 5:00 p.m., Eastern Standard Time, on the Expiration Date (as defined below),          fully paid nonassessable shares of Common Stock (as defined below) of the Company at the Exercise Price per share provided in Section 1(c) of this Warrant, subject to adjustment as provided below. Capitalized terms used herein but not defined shall have the same meanings assigned to them in the Securities Purchase Agreement dated as of May 16, 2006, by and between the Company and the parties listed on the Schedule of Buyers attached thereto as Exhibit A (as such agreement may be amended, supplemented and modified from time to time as provided in such agreement, the “Securities Purchase Agreement”).

This Warrant (as defined below) is one of a series of Warrants issued in connection with the transactions described in (i) the Securities Purchase Agreement and (ii) certain other related documents and agreements including, without limitation, the Transaction Documents (as defined in the Securities Purchase Agreement). The Warrant Shares (as defined below) issued upon exercise of this Warrant and the holder hereof and thereof shall be entitled to all of the rights and privileges set forth in the Transaction Documents. The Warrants are issued under and pursuant to a Warrant Agent Agreement dated as of May 16, 2006 (herein called the “Warrant Agent Agreement”), between the Company and Wells Fargo Bank, National Association (herein called the “Warrant Agent”).

Section 1. Definitions . The following terms as used in this Warrant shall have the following meanings:

(a) “Bloomberg” means Bloomberg Financial Markets.

(b) “Business Day” means any day other than Saturday, Sunday or other day on which commercial banks in the City of New York are required by law or executive order to remain closed.

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(c) “Common Stock” means (i) the common stock, $0.01 par value per share, of the Company, and (ii) any capital stock into which such Common Stock shall have been changed or any capital stock resulting from a reclassification of such Common Stock.

(e) “Exercise Price” shall be equal to $3.216, subject to further adjustment as hereinafter provided.

(f) “Expiration Date” means May 16, 2011, or, if such date does not fall on a Trading Day, then the next Trading Day.

(g) “Person” means an individual, a limited liability company, a partnership, a joint venture, a corporation, a joint stock company, a trust, an unincorporated organization or association and a government or any department or agency thereof.

(h) “Principal Market” shall have the meaning ascribed thereto in the Securities Purchase Agreement.

(i) “Registration Rights Agreement” means that certain Registration Rights Agreement, dated as of May 16, 2006, among the Company and the initial purchasers of the Notes and the Warrants as such agreement may be amended, supplemented and modified from time to time in a writing signed by all of the signatories thereto.

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

(k) “Successor Entity” means the Person formed by, resulting from or surviving any Fundamental Transaction or the Person with which such Fundamental Transaction shall have been entered into.

(l) “Trading Day” shall mean (x) a day on which the Principal Market is open for business or (y) if the applicable security is not so listed on a Principal Market or admitted for trading or quotation, a Business Day.

(m) “Warrant” means this Warrant and the other warrants to purchase shares of Common Stock issued pursuant to the Securities Purchase Agreement and all warrants issued in exchange, transfer or replacement thereof.

(n) “Warrant Shares” means all shares of Common Stock issuable upon exercise of the Warrants.

Section 2. Exercise of Warrant.

(a) Subject to the terms and conditions hereof, including the early termination of this Warrant pursuant to Section 3(b) of this Warrant, this Warrant may be exercised by the holder hereof then registered on the books of the Company, in whole or in part, at any time on any Business Day on or after the opening of business on the date hereof and prior to 5:00 p.m., Eastern Time, on the Expiration Date by (i) delivery of a written notice, in the form of the subscription notice attached as Exhibit A hereto or a reasonable facsimile thereof (the “Exercise Notice”), to the Company at the principal corporate trust office of the Warrant Agent and to the Company’s designated transfer agent (the “Transfer Agent”), of such holder’s election to

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exercise all or a portion of this Warrant, which notice shall specify the number of Warrant Shares to be purchased, (ii) (A) payment to the Warrant Agent of an amount equal to the Exercise Price multiplied by the number of Warrant Shares as to which this Warrant is being exercised (the “Aggregate Exercise Price”) in cash or delivery of a certified check or bank draft payable to the order of the Warrant Agent or wire transfer of immediately available funds or (B) notification to the Company at the principal corporate trust office of the Warrant Agent and to the Transfer Agent that this Warrant is being exercised pursuant to a Cashless Exercise (as defined in Section 2(e) of this Warrant), and (iii) the surrender of this Warrant to a common carrier for overnight delivery to the Warrant Agent as soon as practicable following such date (or an indemnification undertaking or other form of security reasonably satisfactory to the Company with respect to this Warrant in the case of its loss, theft or destruction, or an affidavit of lost Warrant, in accordance with Section 11); provided, however, that if such Warrant Shares are to be issued in any name other than that of the registered holder of this Warrant, such issuance shall be deemed a transfer and the provisions of Section 8 of this Warrant shall be applicable. In the event of any exercise of the rights represented by this Warrant in compliance with this Section 2(a), the Company shall, as soon as practicable, but in no event later than the third Business Day (the “Warrant Share Delivery Date”) following the date of receipt by the Warrant Agent of the Exercise Notice, the Aggregate Exercise Price (or notice of Cashless Exercise) and this Warrant (or an indemnification undertaking or other form of security reasonably satisfactory to the Company with respect to this Warrant in the case of its loss, theft or destruction, or an affidavit of lost Warrant, in accordance with Section 11) (the “Exercise Delivery Documents”), (A) in the case of a public resale of such Warrant Shares, at the holder’s request, to credit such aggregate number of shares of Common Stock to which the holder shall be entitled to the holder’s or its designee’s balance account with The Depository Trust Company (“DTC”) through its Deposit Withdrawal At Custodian system to the extent then eligible to be deposited with DTC under the rules of such depositary or (B) to issue and deliver to the address as specified in the Exercise Notice, a certificate or certificates in such denominations as may be requested by the holder in the Exercise Notice, registered in the name of the holder or its designee, for the number of shares of Common Stock to which the holder shall be entitled upon such exercise. Upon delivery of the Exercise Delivery Documents, the holder of this Warrant shall be deemed for all corporate purposes to have become the holder of record of the Warrant Shares with respect to which this Warrant has been exercised, irrespective of the date of delivery of this Warrant as required by clause (iii) above or the certificates evidencing such Warrant Shares. In the case of a dispute as to the determination of the Exercise Price or the arithmetic calculation of the number of Warrant Shares, the Company shall promptly issue to the holder the number of shares of Common Stock that is not disputed and shall submit the disputed determination or arithmetic calculation to the holder via facsimile within two (2) Business Days after receipt of the holder’s Exercise Notice. If the holder and the Company are unable to agree upon the determination of the Exercise Price or arithmetic calculation of the number of Warrant Shares within two (2) Business Days of such disputed determination or arithmetic calculation being submitted to the holder, then the Company shall immediately submit via facsimile (i) the disputed determination of the Exercise Price or the Average Price (as defined in Section 9(f) of this Warrant) to an independent, reputable investment banking firm selected jointly by the Company and the holder or (ii) the disputed arithmetic calculation of the number of Warrant Shares to its independent, outside auditor. The Company shall cause the investment banking firm to perform the determination or calculation and notify the Company and the holder of the results no later

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than ten (10) Business Days from the time it receives the disputed determination or calculation. Such investment banking firm’s calculation shall be deemed conclusive absent demonstrable error. All fees and expenses of such determinations shall be borne solely by the Company.

(b) Unless the rights represented by this Warrant shall have expired or shall have been fully exercised, the Company shall, as soon as practicable but in no event later than five (5) Business Days after any exercise (the “Warrant Delivery Date”) and at its own expense, issue a new Warrant identical in all respects to this Warrant exercised except it shall represent rights to purchase the number of Warrant Shares purchasable immediately prior to such exercise under this Warrant, less the number of Warrant Shares with respect to which this Warrant is exercised.

(c) Notwithstanding anything contained in this Warrant to the contrary, the Company shall not be required to issue fractions of shares of Common Stock upon exercise of this Warrant or to distribute certificates which evidence such fractional shares. If more than one Warrant shall be presented for exercise in full at the same time by the same holder, the number of full shares of Common Stock which shall be issuable upon the exercise thereof shall be computed on the basis of the aggregate number of shares of Common Stock purchasable on exercise of all Warrants so presented. In lieu of any fractional shares, there shall be paid to the holder an amount of cash equal to the same fraction of the current market value of a share of Common Stock. For purposes of this Section 2(c) of this Warrant, the current market value of a share of Common Stock shall be the Average Price of a share of Common Stock for the Trading Day immediately prior to the date of such exercise or if not listed on a Principal Market, then as determined in good faith by a majority of the Company’s Board of Directors, whose determination shall be final, binding and conclusive.

(d) If the Company shall fail for any reason or for no reason (except in the case of a dispute as to the Exercise Price or the Average Price which is being resolved in accordance with Section 2(a) of this Warrant) to issue to the holder within three (3) Business Days of receipt of the Exercise Delivery Documents, a certificate for the number of shares of Common Stock to which the holder is entitled or to credit the holder’s or its designee’s balance account with DTC, in accordance with Section 2 of this Warrant, for such number of shares of Common Stock to which the holder is entitled upon the holder’s exercise of this Warrant or a new Warrant for the number of shares of Common Stock to which such holder is entitled pursuant to Section 2(b) of this Warrant, the Company shall, in addition to any other remedies under this Warrant or the Securities Purchase Agreement or otherwise available to such holder, including any indemnification under Section 8 of the Securities Purchase Agreement, pay as additional damages in cash to such holder on each day after the Warrant Share Delivery Date if such exercise is not timely effected and/or each day after the Warrant Delivery Date if such Warrant is not delivered, as the case may be, an amount equal to two percent (2.0%) per month multiplied by the product of (I) the sum of the number of shares of Common Stock not issued to the holder on or prior to the Warrant Share Delivery Date and to which such holder is entitled and, in the event the Company has failed to deliver a Warrant to the holder on or prior to the Warrant Delivery Date and to which such holder is entitled, the number of shares of Common Stock issuable upon exercise of the Warrant as of the Warrant Delivery Date and (II) the Closing Price of the Common Stock on the Warrant Share Delivery Date, in the case of failure to deliver Common Stock, or on the Warrant Delivery Date, in the case of failure to deliver a Warrant, provided that if the Common Stock is not listed on a Principal Market, then the Closing Price shall be as determined in good faith by a majority of the Company’s Board of Directors.

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(e) Notwithstanding anything contained herein to the contrary, the holder of this Warrant may, at its election exercised in its sole discretion, exercise this Warrant as to all or a portion of the Warrant Shares and, in lieu of making the cash payment otherwise contemplated to be made to the Company upon such exercise in payment of the Aggregate Exercise Price, elect instead to receive upon such exercise the “Net Number” of shares of Common Stock determined according to the following formula (a “Cashless Exercise”):

Net Number = (A x B) — (A x C)

                          B

For purposes of the foregoing formula:

A= the total number of shares with respect to which this Warrant is then being exercised.

B= the Current Market Price of the Common Stock on the Trading Day immediately preceding the date of the Exercise Notice.

C= the Exercise Price then in effect for the applicable Warrant Shares at the time of such exercise.

(f) [INCLUDE THE FOLLOWING PARAGRAPH ONLY IF HOLDER HAS ELECTED TO BE GOVERNED BY SECTION 2(k)(A) OF THE SECURITIES PURCHASE AGREEMENT:]

The Company shall not effect the exercise of this Warrant, and the Holder shall not have the right to exercise this Warrant, to the extent that after giving effect to such exercise (x) the number of shares of Common Stock beneficially owned by such holder (together with such holder’s affiliates) (other than the shares which would otherwise be deemed beneficially owned except for being subject to a limitation on exercise analogous to the limitation contained in this Section 2(f)) plus (y) the number of shares of Common Stock issuable upon the exercise of such Warrants would be equal to or exceed 9.99% of the number of shares of Common Stock then issued and outstanding (after giving effect to such exercise), it being the intent of the Company and the holder that the holder not be deemed at any time to have the power to vote or dispose of greater than 9.99% of the number of shares of Common Stock issued and outstanding. As used herein, beneficial ownership shall be determined in accordance with Section 13(d) of the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder. To the extent that the limitation contained in this Section 2(f) applies (and without limiting any rights the Company may otherwise have), the Company may rely on the holder’s determination of whether the Warrants are exercisable pursuant to the terms hereof, the Company having no obligation whatsoever to verify or confirm the accuracy of such determination, and the submission of the Exercise Notice by the holder shall be deemed to be the holder’s representation that the Warrants specified therein are exercisable pursuant to the terms hereof. Nothing contained herein shall be deemed to restrict the right of a holder to exercise the Warrants at such time as the exercise thereof will not violate the provisions of this Section 2(f).