Exhibit 10.1

SUBSCRIPTION AGREEMENT

This Subscription Agreement (the “ Agreement ”) is dated as of December [    ], 2012 (the “ Effective Date ”), between ARCA biopharma, Inc., a Delaware corporation (the “ Company ”), and the Purchaser identified on the signature page hereto (the “ Purchaser ”).

WHEREAS, subject to the terms and conditions set forth in this Agreement and pursuant to an exemption from registration under Section 4(2) of the Securities Act of 1933, as amended (the “ Securities Act ”), the Company has authorized the sale and issuance to an investor of up to an aggregate of                      units (the “ Units ”), with each Unit consisting of: (1) one share of the Common Stock (each a “ Share , and, collectively, the “ Shares ”) and (2) one warrant (each a “ Warrant ” and, collectively, the “ Warrants ”) to purchase 0.75 of a share of Common Stock, in the form attached hereto as Exhibit A , for a purchase price of $         per Unit.

WHEREAS, the Company desires to issue and sell to the Purchaser, and the Purchaser desire to purchase from the Company, Units as more fully described in this Agreement.

WHEREAS, at the Closing, the parties hereto shall execute and deliver a Registration Rights Agreement, in the form attached hereto as Exhibit B (the “ Registration Rights Agreement ”), pursuant to which the Company has agreed to provide certain registration rights with respect to the Registrable Securities (as defined in the Registration Rights Agreement), under the Securities Act and the rules and regulations promulgated thereunder, and applicable state securities laws.

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.

“ Commission ” means the United States Securities and Exchange Commission.

“ Common Stock ” means (i) the Company’s shares of common stock, $0.001 par value per share, and (ii) any capital stock into which such common stock shall have been changed or any share capital resulting from a reclassification of such common stock.

“ Common Stock Equivalents ” means any securities of the Company or its 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 Cooley LLP.

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

“ Exempt Issuance ” means the issuance of (a) shares of Common Stock or options to employees, officers or directors of, or consultants to, the Company pursuant to any stock or option plan duly adopted by the Board of Directors for such purpose, including, but not limited to, the Company’s Amended and Restated 2004 Equity Incentive Plan and the Company’s Non-Employee Director Stock Option Plan, (b) shares of Common Stock issued upon the conversion or exercise of Common Stock Equivalents issued prior to the Effective Date, provided that the conversion or exercise (as the case may be) of any such Common Stock Equivalent is made solely pursuant to the conversion or exercise (as the case may be) provisions of such Common Stock Equivalent that were in effect on the date immediately prior to the Effective Date, the conversion or exercise price of any such Common Stock Equivalents is not lowered, none of such Common Stock Equivalents are (nor is any provision of any such Common Stock Equivalents) amended or waived in any manner (whether by the Company or the holder thereof) to increase the number of shares issuable thereunder and none of the terms or conditions of any such Common Stock Equivalents are otherwise materially changed or waived (whether by the Company or the holder thereof) in any manner that adversely affects the Purchaser and (c) securities issued pursuant to acquisitions or strategic transactions approved by a majority of the disinterested directors of the Company.

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

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

“ Liens ” means a lien, charge, security interest, encumbrance, right of first refusal, preemptive right or other restriction.

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

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

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“ 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, including, without limitation, any Trading Market.

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

“ Purchaser Party ” shall have the meaning ascribed to such term in Section 4.8 .

“ Registration Statement ” shall have the meaning ascribed to such term in the Registration Rights Agreement.

“ 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 ” means the Shares, the Warrants and the Warrant Shares.

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

“ Short Sales ” means all “short sales” as defined in Rule 200 of Regulation SHO under the Exchange Act.

“ Subscription Amount ” means the aggregate amount to be paid for Shares and Warrants purchased hereunder as specified below the Purchaser’s name on the signature page of this Agreement and next to the heading “Subscription Amount,” in United States dollars and in immediately available funds.

“ Trading Day ” shall have the meaning ascribed to such term in the Warrant.

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

“ Transaction Documents ” means, collectively, this Agreement, the Warrant, the Registration Rights Agreement, the Irrevocable Transfer Agent Instructions (as defined below) and each of the other agreements and instruments entered into or delivered by any of the parties in connection with the transactions contemplated hereby and thereby, as may be amended from time to time

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“ Transfer Agent ” means Computershare Trust Company, N.A., the current transfer agent of the Company, with a mailing address of PO Box 43070 Providence, RI 02940-3070, and any successor transfer agent of the Company.

“ Warrant Shares ” means the shares of Common Stock issuable upon exercise of the Warrants.

ARTICLE II.

PURCHASE AND SALE

2.1 Closing . Subject to the satisfaction (or waiver) of the conditions set forth in Sections 2.3(a) and 2.3(b), the Company shall issue and sell to the Purchaser, and the Purchaser shall purchase from the Company on the Closing Date (as defined below), the number of Units set forth on the signature page hereto. At the Closing, each Purchaser shall deliver to the Company, via wire transfer of immediately available funds equal to the Purchaser’s Subscription Amount as set forth on the signature page hereto executed by the Purchaser, less reimbursable expenses payable by the Company to the Purchaser pursuant to Section 5.2 (the “ Net Subscription Amount ”), and the Company shall deliver to each Purchaser its respective Shares and a Warrant as determined pursuant to Section 2.2(a), and the Company and the Purchaser shall deliver the other items set forth in Section 2.2 deliverable at the Closing. The closing (the “ Closing ”) of the sale by the Company to the Purchaser, and the purchase by the Purchaser from the Company, of the number of Units set forth on each Purchaser’s signature page hereto shall occur at the offices of Company Counsel. The date and time of the Closing (the “ Closing Date ”) shall be 8:30 a.m., New York time, on the first Business Day on which the conditions to the Closing set forth in Sections 2.3(a) and 2.3(b) below are satisfied or waived (or such later date as is mutually agreed to by the Company and the Purchaser).

2.2 Deliveries .

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

(i) its duly executed signature page to each of the other Transaction Documents to which it is a party;

(ii) one or more stock certificates, evidencing the Shares;

(iii) a Warrant, duly executed by the Company, registered in the name of the Purchaser to purchase up to the number of Warrant Shares set forth on the signature page hereto, with an exercise price equal to $[*] (such Warrant certificate may be delivered within three trading days of the Closing Date;

(iv) a copy of the Irrevocable Transfer Agent Instructions, in the form acceptable to the Purchaser, which instructions shall have been delivered to and acknowledged in writing by the Company’s transfer agent;

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(v) a certificate evidencing the good standing of the Company issued by the Secretary of State of Delaware as of a date within ten (10) days of the Closing Date;

(vi) a certificate, in the form acceptable to the Purchaser, executed by the Secretary of the Company and dated as of the Closing Date, as to (i) the resolutions consistent with Section 3.1(c) as adopted by the Company’s board of directors in a form reasonably acceptable to the Purchaser; and

(vii) a letter from the Company’s transfer agent certifying the number of shares of Common Stock outstanding on the Closing Date immediately prior to the Closing Date.

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

(i) its duly executed signature page to each of the other Transaction Documents to which it is a party;

(ii) the Purchaser’s Net Subscription Amount by wire transfer to the account as specified in writing by the Company; and

(iii) a fully completed Purchaser Questionnaire, in the form attached hereto as Exhibit C , for the Company’s use in preparing the Registration Statement to be filed by the Company under the Registration Rights Agreement (such Purchaser Questionnaire may be delivered within two Trading Days of the Closing Date).

2.3 Closing Conditions .

(a) The obligation of the Company hereunder to issue and sell the Shares and the Warrants to the Purchaser at the Closing is subject to the satisfaction, at or before the Closing Date, of each of the following conditions, provided that these conditions are for the Company’s sole benefit and may be waived by the Company at any time in its sole discretion by providing the Purchaser with prior written notice thereof:

(i) the representations and warranties made by the Purchaser in Section 3.2 hereof qualified as to materiality shall be true and correct at all times prior to and on the Closing Date, except to the extent any such representation or warranty expressly speaks as of an earlier date, in which case such representation or warranty shall be true and correct as of such earlier date, and, the representations and warranties made by the Purchaser in Section 3.2 hereof not qualified as to materiality shall be true and correct in all material respects at all times prior to and on the Closing Date, except to the extent any such representation or warranty expressly speaks as of an earlier date, in which case such representation or warranty shall be true and correct in all material respects as of such earlier date;

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(ii) all obligations, covenants and agreements of the Purchaser under this Agreement 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 obligation of Purchaser hereunder to purchase the Shares and the Warrant at the Closing is subject to the satisfaction, at or before the Closing Date, of each of the following conditions, provided that these conditions are for each Purchaser’s sole benefit and may be waived by the Purchaser at any time in its sole discretion by providing the Company with prior written notice thereof:

(i) the representations and warranties of the Company that are qualified by a materiality standard or Material Adverse Effect, shall have been true and correct when made and shall be true and correct as of the Closing Date and the representations and warranties of the Company that are not qualified by a materiality standard or Material Adverse Effect, shall have been true and correct when made and shall be true and correct in all material respects as of the Closing Date, and the Company shall have performed, satisfied and complied in all respects with the covenants, agreements and conditions required to be performed, satisfied or complied with by the Company at or prior to the Closing Date, and the Purchaser shall have received a certificate, executed by the Chief Executive Officer or Chief Financial Officer of the Company, dated as of the Closing Date, to the foregoing effect;

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

(iii) the Common Stock (I) shall be designated for quotation or listed on the Principal Market (as defined in the Warrant) and shall not have been suspended, as of the Closing Date, by the Commission or the Principal Market from trading on the Principal Market;

(iv) the Company shall have obtained all governmental, regulatory or third party consents and approvals, if any, necessary for the sale of the Securities, including without limitation, those required by the Principal Market;

(v) no statute, rule, regulation, executive order, decree, ruling or injunction shall have been enacted, entered, promulgated or endorsed by any court or governmental authority of competent jurisdiction that prohibits the consummation of any of the transactions contemplated by the Transaction Documents;

(vi) since the date of execution of this Agreement, no event or series of events shall have occurred that reasonably would have or result in a Material Adverse Effect; and

(vii) the Company shall have filed with Nasdaq a Notification Form: Listing of Additional Shares for the listing of the Shares and the Warrant Shares, a copy of which shall have been made available to the Purchaser.

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ARTICLE III.

REPRESENTATIONS AND WARRANTIES

3.1 Representations and Warranties of the Company . The Company represents and warrants to Purchaser as follows:

(a) Subsidiaries . The Company owns, directly or indirectly, all of the capital stock or other equity interests of each of its direct and indirect subsidiaries free and clear of any Liens, and all of the issued and outstanding shares of capital stock of each such subsidiary are validly issued and are fully paid, non-assessable and free of preemptive and similar rights to subscribe for or purchase securities, except as set forth on Schedule 3.1(a) hereto. The Company or one of its subsidiaries has the unrestricted right to vote, and (subject to limitations imposed by applicable law) to receive dividends and distributions on, all capital securities of its subsidiaries as owned by the Company or such subsidiary. If the Company has no subsidiaries, all other references to subsidiaries in the Transaction Documents shall be disregarded.

(b) Organization and Qualification . The Company and each of its 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, 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 nor default of any of the provisions of its respective certificate or articles of incorporation, bylaws or other organizational or charter documents. Each of the Company and its 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 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 its 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 (any of (i), (ii) or (iii), a “ Material Adverse Effect ”) and no Proceeding has been instituted in any such jurisdiction revoking, limiting or curtailing or seeking to revoke, limit or curtail such power and authority or qualification.

(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

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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 to which it is a party 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 by the Company of the Transaction Documents, the issuance and sale of the Shares and Warrants and the consummation by it of the transactions contemplated hereby and thereby to which it is a party 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) 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 or conflict with, or constitute a default (or an event that with notice or lapse of time or both would become a default) under, any agreement, credit facility, debt or other instrument (evidencing a Company or subsidiary debt or otherwise) or other 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 the Required Approvals, conflict with or result in a violation of any law, rule, regulation, order, judgment, injunction, decree or other restriction of any Trading Market, 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 Trading Market), 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 reasonably be 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 other Person in connection with the execution, delivery and performance by the Company of the Transaction Documents, other than: (i) the filing with the Commission of a Registration Statement, (iii) the filing with the Commission of a Form D; (iv) application(s) to each applicable Trading Market for the listing or designation for quotation (as the case may be) of the Shares and Warrant Shares for trading thereon in the time and manner required thereby and (iv) such filings as are required to be made under applicable state securities laws (collectively, the “ Required Approvals ”). All consents, authorizations, orders, filings and registrations which the Company is required to obtain at or prior to the Closing have been obtained or effected on or prior to the Closing Date, and neither the Company nor any of its subsidiaries are aware of any facts or circumstances which might prevent the Company from obtaining or effecting any of the registration, application or filings contemplated by the Transaction Documents.

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(f) Issuance of the Securities . The Shares and Warrants are duly authorized and, when issued and paid for in accordance with the applicable Transaction Documents (i) the Shares will be duly and validly issued, fully paid and nonassessable, free and clear of all Liens imposed by the Company and (ii) the Warrants will be duly and validly issued, free and clear of all Liens imposed by the Company. The Warrant Shares, when issued in accordance with the terms of the Warrants, will be validly issued, fully paid and nonassessable, free and clear of all Liens imposed by the Company. The Company has reserved from its duly authorized capital stock the maximum number of shares of Common Stock issuable pursuant to this Agreement and the Warrants.

(g) Capitalization . 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 stock options under the Company’s stock option plans, the issuance of shares of Common Stock to employees pursuant to the Company’s employee stock purchase plans and pursuant to the conversion and/or exercise of Common Stock Equivalents outstanding as of the date of the most recently filed periodic report under the Exchange Act. 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 described in the Company’s SEC Reports. Except as described in the Company’s SEC Reports, 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 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, other than as a result of the purchase and sale of the Shares and Warrants or the exercise of the Warrants. The issuance and sale of the Shares and Warrants, and the issuance of Warrant Shares upon exercise of the Warrants, will not obligate the Company to issue shares of Common Stock or other securities to any Person (other than the Purchaser) 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. No further approval or authorization of any stockholder, the Board of Directors or others is required for the issuance and sale of the Securities. There are no stockholders agreements, voting 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 that are not described in the SEC Reports.

(h) SEC Reports; Financial Statements . The Company has filed all reports, schedules, forms, statements and other documents required to be filed by the Company under the Exchange Act, including pursuant to Section 13(a) or 15(d) thereof, for the two years preceding the Effective Date (or such shorter period as the Company was required by law or regulation to file such material) (all of the foregoing filed prior to the date

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hereof and all exhibits included therein and financial statements, notes and schedules thereto and documents incorporated by reference therein being hereinafter referred to collectively as the “ SEC Reports ”) on a timely basis or has received a valid extension of such time of filing and has filed any such SEC Reports prior to the expiration of any such extension. As of their respective dates, the SEC Reports complied in all material respects with the requirements of the Exchange Act, as applicable, and the rules and regulations of the Commission promulgated thereunder applicable thereto, and none of the SEC Reports, when filed, 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. 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 accordance with United States generally accepted accounting principles applied on a consistent basis during the periods involved (“ GAAP ”) (except (i) as may be otherwise indicated in such financial statements or the notes thereto, or (ii) in the case of unaudited interim statements, to the extent they may exclude footnotes or may be condensed or summary statements), and such financial statements 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 results of operations and cash flows for the periods then ended, subject, in the case of unaudited statements, to normal, year-end audit adjustments, which will not be material, either individually or in the aggregate.

(i) Material Changes; Undisclosed Events, Liabilities or Developments . Since the date of the latest audited financial statements included within the SEC Reports, except as specifically disclosed in a subsequent SEC Report filed prior to the Effective Date or otherwise known to Purchaser, (i) there has been no event, occurrence or development that has had, or that could reasonably be expected to result in, a Material Adverse Effect, (ii) the Company has not incurred any liabilities (contingent or otherwise) other than (A) trade payables and accrued expenses incurred in the ordinary course of business consistent with past practice and (B) liabilities not required to be reflected in the Company’s financial statements pursuant to GAAP or disclosed in filings made with the Commission, (iii) the Company has not altered its method of accounting, (iv) 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 (v) the Company has not issued any equity securities to any officer, director or Affiliate, except pursuant to existing Company stock option plans. Except for the issuance of the Shares and Warrants contemplated by this Agreement, no event, liability, fact, circumstance, occurrence or development has occurred or exists or is reasonably expected to occur or exist with respect to the Company or its subsidiaries or their respective business, prospects, properties, operations, assets or financial condition that would be required to be disclosed by the Company under applicable securities laws at the time this representation is made or deemed made that has not been publicly disclosed on or before the date that this representation is made. Neither the Company nor any of its subsidiaries has taken any steps to seek protection pursuant to any law or statute relating to bankruptcy, insolvency, reorganization, receivership,

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liquidation or winding up, nor does the Company or any subsidiary have any knowledge or reason to believe that any of their respective creditors intend to initiate involuntary bankruptcy proceedings or any actual knowledge of any fact which would reasonably lead a creditor to do so. The Company and its subsidiaries, on a consolidated basis, are not as of the date hereof, and after giving effect to the transactions contemplated hereby to occur at the Closing, will not be Insolvent (as defined below). “ Insolvent ” means, with respect to the Company and its subsidiaries, on a consolidated basis, (i) the present fair saleable value of the Company’s and its subsidiaries’ assets is less than the amount required to pay the Company’s and its subsidiaries’ total Indebtedness (as defined below), (ii) the Company and its subsidiaries are unable to pay their debts and liabilities, subordinated, contingent or otherwise, as such debts and liabilities become absolute and matured or (iii) the Company and its subsidiaries intend to incur or believe that they will incur debts that would be beyond their ability to pay as such debts mature Neither the Company nor any of its subsidiaries has engaged in any business or in any transaction, and is not about to engage in any business or in any transaction, for which the Company’s or such subsidiary’s remaining assets constitute unreasonably small capital. “ Indebtedness ” of any Person means, without duplication (A) all indebtedness for borrowed money, (B) all obligations issued, undertaken or assumed as the deferred purchase price of property or services (including, without limitation, “capital leases” in accordance with generally accepted accounting principles) (other than trade payables entered into in the ordinary course of business), (C) all reimbursement or payment obligations with respect to letters of credit, surety bonds and other similar instruments, (D) all obligations evidenced by notes, bonds, debentures or similar instruments, including obligations so evidenced incurred in connection with the acquisition of property, assets or businesses, (E) all indebtedness created or arising under any conditional sale or other title retention agreement, or incurred as financing, in either case with respect to any property or assets acquired with the proceeds of such indebtedness (even though the rights and remedies of the seller or bank under such agreement in the event of default are limited to repossession or sale of such property), (F) all monetary obligations under any leasing or similar arrangement which, in connection with generally accepted accounting principles, consistently applied for the periods covered thereby, is classified as a capital lease, (G) all indebtedness referred to in clauses (A) through (F) above secured by (or for which the holder of such indebtedness has an existing right, contingent or otherwise, to be secured by) any mortgage, lien, pledge, charge, security interest or other encumbrance upon or in any property or assets (including accounts and contract rights) owned by any Person, even though the Person which owns such assets or property has not assumed or become liable for the payment of such indebtedness, and (H) all Contingent Obligations in respect of indebtedness or obligations of others of the kinds referred to in clauses (A) through (G) above; and “ Contingent Obligation ” means, as to any Person, any direct or indirect liability, contingent or otherwise, of that Person with respect to any indebtedness, lease, dividend or other obligation of another Person if the primary purpose or intent of the Person incurring such liability, or the primary effect thereof, is to provide assurance to the obligee of such liability that such liability will be paid or discharged, or that any agreements relating thereto will be complied with, or that the holders of such liability will be protected (in whole or in part) against loss with respect thereto.

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(j) Litigation . (i) 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 ”); (ii) neither the Company nor any subsidiary, nor any director or officer thereof is 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 and (iii) 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 or former director or officer of the Company, which, in any case of clauses (i), (ii) or (iii), (A) adversely affects or challenges the legality, validity or enforceability of any of the Transaction Documents or the Securities or (B) could, if there were an unfavorable decision, have or reasonably be expected to result in a Material Adverse Effect.

(k) Labor Relations . No material labor dispute exists or, to the knowledge of the Company, is imminent with respect to any of the employees of the Company that 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, reasonably be expected to have 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 judgment, decree or order of any court, arbitrator or governmental body or (iii) is or has been in violation of any statute, rule, ordinance 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 reasonably be expected to result in a Material Adverse Effect.

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(m) Regulatory Permits . Except as set forth in the SEC Reports, the Company and its subsidiaries possess all certificates, authorizations and permits issued by the appropriate federal, state, local or foreign regulatory authorities necessary to conduct their respective businesses as described in the SEC Reports, except where the failure to possess such permits could not reasonably be expected to result in a Material Adverse Effect (“ Material Permits ”), and 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 its subsidiaries have good and marketable title in fee simple to all real property owned by them and good and marketable title to all personal property owned by them that is material to the business of the Company and its subsidiaries, in each case free and clear of all Liens, except for Liens as 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 its subsidiaries and Liens for the payment of federal, state or other taxes, the payment of which is neither delinquent nor subject to penalties. Any real property and facilities held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases with which the Company and its subsidiaries are in compliance with such exceptions as are not material and do not materially interfere with the use made and proposed to be made of such property and facilities by the Company and its subsidiaries.

(o) Patents and Trademarks . The Company and its 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 reasonably be expected to have 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. The Company and its subsidiaries have taken reasonable security measures to protect the secrecy, confidentiality and value of all of their intellectual properties, except where the failure to do so could not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(p) Insurance . The Company and its subsidiaries are insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are prudent and customary in the businesses in which the Company and its subsidiaries are engaged, including, but not limited to, directors and officers insurance coverage at least equal to the aggregate Subscription Amount. 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 significant increase in cost.

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(q) Transactions With Affiliates and Employees . Except as set forth in the SEC Reports, none of the officers or directors of the Company and, to the knowledge of the Company, none of the 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 . The Company is in material compliance with all provisions of the Sarbanes-Oxley Act of 2002 that are applicable to it as of the Closing Date.

(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 have no 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 immediately after receipt of payment for the Shares and Warrants, will not be an “investment company” within the meaning of the Investment Company Act of 1940, as amended.

(u) Registration Rights . Except as set forth in the SEC Reports, no Person has any right to cause the Company to effect the registration under the Securities Act of any securities of the Company as a result of the transactions contemplated by this Agreement.

(v) Listing and Maintenance Requirements . The Common Stock is registered pursuant to Section 12(b) or 12(g) of the Exchange Act, and the Company has taken no action designed to, or that 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. Except as set forth in the SEC Reports, the Company has not, in the 12 months preceding the Effective Date, 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 in compliance with all such listing and maintenance requirements. Notwithstanding the foregoing, the Company is currently not in compliance with the minimum bid price requirement of the Nasdaq Capital Market.

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(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, poison pill (including any distribution under a rights agreement) 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 Securities and the Purchaser’s ownership of the any of the Securities.

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

(y) 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.

(z) Accountants . The Company’s independent registered public accounting firm is identified in the SEC Reports and such accounting firm is a registered public accounting firm as required by the Exchange Act.

(aa) 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 Securities, (ii) sold, bid for, purchased, or, paid any compensation for soliciting purchases of, any of the Securities, or (iii) paid or agreed to pay to any Person any compensation for soliciting another to purchase any other securities of the Company.

(bb) No Integrated Offering . None of the Company, its subsidiaries or any of their affiliates, nor any Person acting on 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 Securities to require approval of stockholders of the Company under any applicable stockholder approval provisions,

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including, without limitation, under the rules and regulations of any exchange or automated quotation system on which any of the securities of the Company are listed or designated for quotation.

(cc) Securities Act Exemption . Assuming the accuracy of the representations and warranties of the Purchaser contained in Section 3.2 hereof, the offer and sale of the Securities to the Purchaser as contemplated hereby is exempt from the registration requirements of the Securities Act.

(dd) Shell Company Status . The Company is not, and has never been, an issuer identified in Rule 144(i), and Rule 144(i) has never applied to the Company.

(ee) Indebtedness and Other Contracts . Neither the Company nor any of its subsidiaries (i) except as disclosed in the SEC Reports, has any outstanding Indebtedness, (ii) is a party to any contract, agreement or instrument, the violation of which, or default under which, by the other party(ies) to such contract, agreement or instrument could reasonably be expected to result in a Material Adverse Effect, (iii) is in violation of any term of, or in default under, any contract, agreement or instrument relating to any Indebtedness, except where such violations and defaults would not result, individually or in the aggregate, in a Material Adverse Effect, or (iv) is a party to any contract, agreement or instrument relating to any Indebtedness, the performance of which, in the judgment of the Company’s officers, has or is expected to have a Material Adverse Effect.

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

(a) Organization; Authority . The Purchaser is either an individual or 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. 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, partnership, limited liability company or similar action, as applicable, 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) Investment Experience . The Purchaser (i) is knowledgeable, sophisticated and experienced in making, and is qualified to make decisions with respect to, investments in shares presenting an investment decision like that involved in the purchase of the Units,

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including investments in securities issued by the Company and investments in comparable companies. Purchaser acknowledges its opportunity to review copies of the SEC Reports. At the time the Purchaser was first offered the Securities, it was, and as of 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.

(c) No Legal or Tax Advice . The Purchaser understands that nothing in this Agreement or any other materials presented to the Purchaser in connection with the purchase and sale of the Units constitutes legal, tax or investment advice. The Purchaser has consulted such legal, tax and investment advisors and made such investigation as it, in its sole discretion, has deemed necessary or appropriate in connection with its purchase of Units. The Purchaser also understands that there is no established public trading market for the Warrants being offered pursuant to this Agreement, and that the Company does not expect such a market to develop. In addition, the Company does not intend to apply for listing the Warrants on any securities exchange. Without an active market, the liquidity of the Warrants will be limited.

(d) Investment Intent . The Purchaser (i) is acquiring the Shares and Warrant, and (ii) upon exercise of the Warrant will acquire the Warrant Shares issuable upon exercise thereof, in each case, for its own account and not with a view towards, or for resale in connection with, the public sale or the distribution thereof in violation of applicable securities laws, except pursuant to sales registered or exempted under the Securities Act.

(e) Transfer or Resale . The Purchaser understands that except as provided in the Registration Rights Agreement: (i) the Securities have not been and are not being registered under the Securities Act or any state securities laws, and may not be, and the Purchaser hereby agrees that the Securities may not be, offered for sale, sold, assigned or transferred unless (A) subsequently registered thereunder, (B) the Purchaser shall have delivered to the Company (if requested by the Company) an opinion of counsel to the Purchaser, in a form reasonably acceptable to the Company, to the effect that such Securities to be sold, assigned or transferred may be sold, assigned or transferred pursuant to an exemption from such registration, including pursuant to Rule 144 or Rule 144A promulgated under the Securities Act (or a successor rule thereto) (collectively, “ Rule 144 ”); (ii) any sale of the Securities made in reliance on Rule 144 may be made only in accordance with the terms of Rule 144, and further, if Rule 144 is not applicable, any resale of the Securities under circumstances in which the seller (or the Person through whom the sale is made) may be deemed to be an underwriter (as that term is defined in the Securities Act) may require compliance with some other exemption under the Securities Act or the rules and regulations of the Commission promulgated thereunder; and (iii) neither the Company nor any other Person is under any obligation to register the Securities under the Securities Act or any state securities laws or to comply with the terms and conditions of any exemption thereunder. The Company shall be entitled to give stop transfer instructions to its Transfer Agent with respect to the Securities in order to enforce the foregoing restrictions.

3.3 Residency . The investment decision was made for Purchaser in the jurisdiction indicated below such Purchaser’s name on the applicable signature page hereto.

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3.4 Legend . The Purchaser understands that the Securities have been issued (or will be issued in the case of the Warrant Shares) pursuant to an exemption from registration or qualification under the 1933 Act and applicable state securities laws, and except as set forth below, the Securities shall bear any legend as required by the “blue sky” laws of any state and a restrictive legend in substantially the following form (and a stop-transfer order may be placed against transfer of such stock certificates):

NEITHER THE SECURITIES, NOR THE ISSUANCE AND SALE OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE [EXERCISABLE] HAVE 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 (I) IN THE ABSENCE OF (A) AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) AN OPINION OF COUNSEL TO THE HOLDER (IF REQUESTED BY THE COMPANY), IN A FORM REASONABLY ACCEPTABLE TO THE COMPANY, THAT REGISTRATION IS NOT REQUIRED UNDER SAID ACT OR MAY BE SOLD PURSUANT TO RULE 144 OR RULE 144A UNDER SAID ACT.

ARTICLE IV.

OTHER AGREEMENTS OF THE PARTIES

4.1 Legend Removal; Buy-In .

(a) Removal of Legends . Certificates evidencing Securities shall not be required to contain the legend set forth in Section 3.4 above or any other legend (i) while a registration statement (including a Registration Statement) covering the resale of such Securities is effective under the Securities Act, (ii) if such Securities are, or are eligible to be, sold, assigned or transferred under Rule 144 (provided that the Purchaser provides the Company with reasonable assurances that such Securities are eligible for sale, assignment or transfer under Rule 144 which may include an opinion of counsel if requested by the Company) or (iii) in connection with a sale, assignment or other transfer (other than under Rule 144), provided that the Purchaser provides the Company with an opinion of counsel to the Purchaser, in a form reasonably acceptable to the Company, to the effect that such sale, assignment or transfer of the Securities may be made without registration under the applicable requirements of the Securities Act. If a legend is not required pursuant to the foregoing, the Company shall no later than three (3) Trading Days following the delivery by a the Purchaser to the Company or the transfer agent (with notice to the Company) of a legended certificate representing such Securities (endorsed or with stock powers attached, signatures guaranteed, and otherwise in form necessary to affect the reissuance and/or transfer, if applicable), together with any other deliveries from the Purchaser as may be required above in this Section 4.1(a), as directed by the Purchaser, either: (A) provided that the Transfer Agent is participating in the DTC Fast

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Automated Securities Transfer Program and such Securities are Shares or Warrant Shares, credit the aggregate number of shares of Common Stock to which such the Purchaser shall be entitled to the Purchaser’s or its designee’s balance account with DTC through its Deposit/Withdrawal at Custodian system or (B) if the Transfer Agent is not participating in the DTC Fast Automated Securities Transfer Program, issue and deliver (via reputable overnight courier) to the Purchaser, a certificate representing such Securities that is free from all restrictive and other legends, registered in the name of the Purchaser or its designee (the date by which such credit is so required to be made to the balance account of the Purchaser’s or the Purchaser’s nominee with DTC or such certificate is required to be delivered to the Purchaser pursuant to the foregoing is referred to herein as the “ Required Delivery Date ”).

(b) Transfer Agent Instructions . The Company shall issue irrevocable instructions to its Transfer Agent in a form acceptable to the Purchaser (the “ Irrevocable Transfer Agent Instructions ”) to issue certificates or credit shares to the applicable balance accounts at The Depository Trust Company (“ DTC ”), registered in the name of the Purchaser or its respective nominee(s), for the Shares and the Warrant Shares in such amounts as specified from time to time by the Purchaser to the Company upon delivery of the Shares or the exercise of the Warrants (as the case may be). The Company represents and warrants that no instruction other than the Irrevocable Transfer Agent Instructions referred to in this Section 4.1, and stop transfer instructions to give effect to Section 3.2(e) hereof, will be given by the Company to its Transfer Agent with respect to the Securities, and that the Securities shall otherwise be freely transferable on the books and records of the Company, as applicable, to the extent provided in this Agreement and the other Transaction Documents. If the Purchaser effects a sale, assignment or transfer of the Securities in accordance with Section 3.2(e), the Company shall permit the transfer and shall promptly instruct its Transfer Agent to issue one or more certificates or credit shares to the applicable balance accounts at DTC in such name and in such denominations as specified by the Purchaser to effect such sale, transfer or assignment. In the event that such sale, assignment or transfer involves Shares or Warrant Shares sold, assigned or transferred pursuant to an effective Registration Statement or in compliance with Rule 144, the transfer agent shall issue such shares to the Purchaser, assignee or transferee (as the case may be) without any restrictive legend in accordance with Section 3.4 above.

(c) If the Company shall fail for any reason or for no reason to issue to a Purchaser unlegended certificates within three (3) Trading Days of receipt of all documents necessary for the removal of the legend set forth above (the “ Deadline Date ”), then, in addition to all other remedies available to such Purchaser, if on or after the Trading Day immediately following such three (3) Trading Day period, such Purchaser purchases (in an open market transaction or otherwise) shares of Common Stock to deliver in satisfaction of a sale by the holder of shares of Common Stock that such Purchaser anticipated receiving from the Company without any restrictive legend (a “ Buy-In ”), then the Company shall, within three (3) Trading Days after such Purchaser’s request and in such Purchaser’s sole discretion, either (i) pay cash to the Purchaser in an amount equal to such Purchaser’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased (the “ Buy-In Price ”), at which point

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the Company’s obligation to deliver such certificate (and to issue such shares of Common Stock) shall terminate, or (ii) promptly honor its obligation to deliver to such Purchaser a certificate or certificates representing such shares of Common Stock and pay cash to the Purchaser in an amount equal to the excess (if any) of the Buy-In Price over the product of (a) such number of shares of Common Stock, times (b) the closing bid price on the Deadline Date.

4.2 Best Efforts . The Purchaser shall use its best efforts to timely satisfy each of the conditions to be satisfied by it as provided in Section 2.3(a) hereof. The Company shall use its best efforts to timely satisfy each of the conditions to be satisfied by it as provided in Section 2.3(b) of this Agreement.

4.3 Form D and Blue Sky . The Company shall file a Form D with respect to the Securities as required under Regulation D and to provide a copy thereof to the Purchaser promptly after such filing. The Company shall, on or before the Closing Date, take such action as the Company shall reasonably determine is necessary in order to obtain an exemption for, or to, qualify the Securities for sale to the Purchaser at the Closing pursuant to this Agreement under applicable securities or “Blue Sky” laws of the states of the United States (or to obtain an exemption from such qualification), and shall provide evidence of any such action so taken to the Purchaser on or prior to the Closing Date. Without limiting any other obligation of the Company under this Agreement, the Company shall timely make all filings and reports relating to the offer and sale of the Securities required under all applicable securities laws (including, without limitation, all applicable federal securities laws and all applicable “Blue Sky” laws), and the Company shall comply with all applicable federal, foreign, state and local laws, statutes, rules, regulations and the like relating to the offering and sale of the Securities to the Purchaser.

4.4 Reporting Status; Integration; Use of Proceeds .

(a) Until the date on which no Warrants are outstanding, the Company shall timely file all reports required to be filed with the Commission pursuant to the Exchange Act, and the Company shall not terminate its status as an issuer required to file reports under the Exchange Act even if the Exchange Act or the rules and regulations thereunder would no longer require or otherwise permit such termination.

(b) 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 Securities for purposes of the rules and regulations of any Trading Market such that it would require stockholder approval prior to the closing of such other transaction unless the stockholder approval required under such rules and regulations is actually obtained before the closing of such subsequent transaction that gives rise to the integration.

(c) The Company shall use the proceeds from the sale of the Securities solely for general working capital purposes.

4.5 Securities Laws Disclosure; Publicity . The Company shall by 8:30 a.m. (New York City time) on the Effective Date file a Current Report on Form 8-K disclosing the material

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terms of the transaction and including the Transaction Documents as exhibits thereto. The Company and the Purchaser shall consult with each other in issuing any press releases with respect to the transactions contemplated hereby, and neither the Company nor the Purchaser shall issue any such press release nor otherwise make any such public statement without the prior consent of the Company, with respect to any press release of the Purchaser, or without the prior consent of the Purchaser, with respect to any press release of the Company, which consent shall not unreasonably be withheld or delayed, except if such disclosure is required by law.

4.6 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” 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 any of the Securities under the Transaction Documents or under any other agreement between the Company and the Purchaser.

4.7 Indemnification . Subject to the provisions of this Section 4.8, the Company will indemnify and hold each 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 liabilities, claims, damages, costs and expenses, including all judgments, amounts paid in settlements, court costs and reasonable attorneys’ fees and costs of investigation (collectively, “ Losses ”) that any such Purchaser Party incurs as a result of (a) any material breach of any representation or warranty made by the Company in any of the Transaction Documents, (b) any breach of any covenant, agreement or obligation of the Company contained in any of the Transaction Documents or (c) any action, suit or claim instituted against a Purchaser Party in any capacity, or any of them or their respective Affiliates, by any stockholder of the Company or other third party, in each case who is not an Affiliate of the applicable Purchaser Party, resulting from or relating to any of the transactions contemplated by any of the Transaction Documents (except to the extent, and only to the extent, such action is based upon a material breach of the Purchaser’s representations, warranties or covenants under the Transaction Documents, a material breach of any agreements or understandings the Purchaser may have with any such stockholder or material violations by the Purchaser of state or federal securities laws, or any conduct by the Purchaser which constitutes fraud, gross negligence, willful misconduct or malfeasance). To the extent that the foregoing undertaking by the Company may be unenforceable for any reason, the Company shall make the maximum contribution to the payment and satisfaction of each of the Losses which is permissible under applicable law and is consistent with the standards for contribution set forth in Section 6 of the Registration Rights Agreement as if they applied to the foregoing. Except as otherwise set forth herein, the mechanics, procedures, standards and limitations with respect to the rights and obligations under this Section 4.8 (including, without limitation, any requirements for giving of notices, the right to control defense and settlement of any proceeding, the ability to participate in any defense, and limitations on settlement of actions and the effects of unauthorized settlement) shall be the same as those set forth in Section 6 of the Registration Rights Agreement.

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4.8 Reservation of Common Stock . As of the Effective Date, the Company has reserved and the Company shall continue to reserve and keep available at all times, free of preemptive rights, a sufficient number of shares of Common Stock for the purpose of enabling the Company to issue Shares pursuant to this Agreement and Warrant Shares pursuant to any exercise of the Warrants (without regard to any limitations on the exercise of the Warrants set forth therein).

4.9 Listing of Common Stock . The Company hereby agrees to use best efforts to maintain the listing or quotation of the Common Stock on the Trading Market on which it is currently listed, and the Company shall promptly secure the listing of all of the Shares and the Warrant Shares on such Trading Market (but in no event later than the Closing Date). The Company further agrees, if the Company applies to have the Common Stock traded on any other Trading Market, it will then include in such application all of the Shares and Warrant Shares, and will take such other action as is necessary to cause all of the Shares and the Warrant Shares to be listed or quoted on such other Trading Market as promptly as possible. The Company will then 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.

4.10 Certain Transactions and Confidentiality . Each Purchaser shall either be under an obligation of confidentiality by virtue of its fiduciary status, or have entered into a confidentiality agreement with the Company prior to the Effective Date. Subject to the terms of the Confidentiality Agreement, the Purchaser covenants that neither it nor any Affiliate acting on its behalf or pursuant to any understanding with it will execute any purchases or sales, including Short Sales of any of the Company’s securities during the period commencing with the execution of this Agreement and ending at such time that a Registration Statement covering the securities is effective. The Purchaser covenants that until such time as the transactions contemplated by this Agreement are publicly disclosed, the Purchaser will maintain the confidentiality of the existence and terms of this transaction.

4.11 Other Terms . The Company represents, warrants and covenants that the Company has not entered into, and will not enter into, any agreement or instrument with, or for the benefit of, any of the other Purchaser or any other third party purchaser of securities of the Company substantially concurrent with the Closing on terms or conditions which are more favorable to any such other Purchaser or third party purchaser than the terms and conditions provided to, or for the benefit of, the Purchaser. To the extent the Company enters into any agreement or instrument with, or for the benefit of, any of such other PurchaserPurchaser or any such third party purchaser that contains any terms or conditions which are more favorable to any of such other Purchaser or any such third party purchaser than the terms and conditions provided to, or for the benefit of, the Purchaser herein, then each Purchaser, at its option, shall be entitled to the benefit of such more favorable terms or conditions (as the case may be) and this Agreement shall be automatically amended to reflect such more favorable terms or conditions (as the case may be).

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ARTICLE V.

MISCELLANEOUS

5.1 Termination . This Agreement may be terminated by the Purchaser or the Company upon written notice to the other party if the Closing has not been consummated on or before the fifth (5 ^th ) Trading Day following the Effective Date, provided that a party shall not have the right to so terminate this Agreement if it breaches any of its obligations under this Agreement. Nothing contained in this Section 5.1 shall be deemed to release any party from any liability for any breach by such party of the terms and provisions of this Agreement or the other Transaction Documents or to impair the right of any party to compel specific performance by any other party of its obligations under this Agreement or the other Transaction Documents.

5.2 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 any Securities to the Purchaser.

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

5.4 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 second (2 ^nd ) 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 address for such notices and communications shall be as set forth on the signature pages attached hereto.

5.5 Amendments; Waivers . Except as expressly contemplated by Section 4.13, provisions of this Agreement and each other Subscription Agreement may be amended only with the written consent of the Company and the Required Investors (as defined in the Registration Rights Agreement). Any amendment effected in accordance with this Section 5.5 shall be binding upon each of the Purchaser and the Company, provided that no such amendment shall be effective to the extent that it (a) applies to less than all of the Purchaser, (b) imposes any obligation or liability on any Purchaser without the Purchaser’s prior written consent (which may be granted or withheld in that Purchaser’s sole discretion) or (c) applies retroactively. No waiver shall be effective unless it is in writing and signed by an authorized representative of the waiving party, provided that the Required Investors (in a writing signed by all of the Required Investors)

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may waive any provision of this Agreement and each of the other Subscription Agreements, and any waiver of any provision of this Agreement and the other Subscription Agreements made in conformity with the provisions of this Section 5.5 shall be binding on each of the Purchaser, provided further that no such waiver shall be effective to the extent that it (1) applies to less than all of the Purchaser (unless a party gives a waiver as to itself only) or (2) imposes any obligation or liability on any Purchaser without that Purchaser’s prior written consent (which may be granted or withheld in that Purchaser’s sole discretion). No consideration shall be offered or paid to any Person to amend or consent to a waiver or modification of any provision of this Agreement or any of the other Subscription Agreements unless the same consideration also is offered to all of the parties to all of the Purchaser. 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 any party to exercise any right hereunder in any manner impair the exercise of any such right.

5.6 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.

5.7 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 or other transaction in which substantially all the assets of the Company are acquired). The Purchaser may assign any or all of its rights under this Agreement to any Person to whom the Purchaser assigns or transfers any Securities in accordance with Section 3.2(e), with the prior written consent of the Company, as long as such Person agrees in writing prior to such transfer to be bound with respect to the transferred Securities as a Purchaser hereunder, in which event such assignee shall be deemed to be the Purchaser hereunder with respect to such assigned rights.

5.8 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 .

5.9 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

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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, in addition to the obligations of the Indemnifying Parties under Section 4.8 , 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. Nothing contained in this Section 5.9 shall limit any provision of Section 13 of the Warrant.

5.10 Survival . The representations, warranties and covenants contained herein shall survive the Closing and the delivery of the Shares and Warrants.

5.11 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 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.

5.12 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.

5.13 Replacement of Securities . If any certificate or instrument evidencing any Securities 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, 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 Securities.

5.14 Remedies . In addition to being entitled to exercise all rights provided herein or granted by law, including recovery of damages, each of the Purchaser and the Company will be

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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 obligations contained in the Transaction Documents and hereby agree 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.

5.15 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.

5.16 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. No specific representation or warranty shall limit the generality or applicability of a more general representation or warranty. In addition, each and every reference to share prices and shares of Common Stock in any Transaction Document shall be subject to adjustment for reverse and forward stock splits, stock dividends, stock combinations and other similar transactions of the Common Stock that occur after the Effective Date.

5.17 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 EXTENT PERMITTED BY APPLICABLE LAW, HEREBY ABSOLUTELY, UNCONDITIONALLY, IRREVOCABLY AND EXPRESSLY WAIVES FOREVER TRIAL BY JURY.

(Signature Pages Follow)

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

Broomfield, CO 80021-8023

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK

SIGNATURE PAGES FOR PURCHASER FOLLOWS]

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

Address for Delivery of Securities for Purchaser (if not same as address for notice):

Subscription Amount:                      Units consisting of:

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Exhibit 10.2

REGISTRATION RIGHTS AGREEMENT

This REGISTRATION RIGHTS AGREEMENT (this “ Agreement ”), dated as of December     , 2012, is by and among ARCA biopharma, Inc., a Delaware corporation (the “ Company ”), and the undersigned buyer ( “ Buyer ”).

RECITALS

A. In connection with that certain Subscription Agreement by and between the Company and Buyer, dated as of December     , 2012 (the “ Securities Purchase Agreement ”), the Company has agreed, upon the terms and subject to the conditions of the Securities Purchase Agreement, to issue and sell to Buyer (i) shares (the “ Common Shares ”) of Common Stock (as defined in the Securities Purchase Agreement) and (ii) the Warrants (as defined in the Securities Purchase Agreement), which will be exercisable for Warrant Shares (as defined in the Securities Purchase Agreement) in accordance with the terms of the Warrants.

B. To induce the Buyer to consummate the transactions contemplated by the Securities Purchase Agreement, the Company has agreed to provide certain registration rights under the Securities Act of 1933, as amended, and the rules and regulations thereunder, or any similar successor statute (collectively, the “ 1933 Act ”), and applicable state securities laws.

AGREEMENT

NOW, THEREFORE, in consideration of the premises and the mutual covenants contained herein and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company and the Buyer hereby agree as follows:

Capitalized terms used herein and not otherwise defined herein shall have the respective meanings set forth in the Securities Purchase Agreements. As used in this Agreement, the following terms shall have the following meanings:

(a) “ Business Day ” means any day other than Saturday, Sunday or any other day on which commercial banks in New York, New York are authorized or required by law or other governmental action to remain closed.

(b) “ Closing Date ” shall have the meaning set forth in the Securities Purchase Agreements.

(c) “ Effective Date ” means the date that the applicable Registration Statement has been declared effective by the SEC.

(d) “ Effectiveness Deadline ” means (i) with respect to the initial Registration Statement required to be filed pursuant to Section 2(a), the earlier of the (A) 90 ^th calendar day after the Closing Date (or the 120 ^th calendar day after the Closing Date in the event that such Registration Statement is subject to review by the SEC) and (B) 4 ^th Business Day after the date the Company is notified (orally or in writing, whichever is earlier) by the SEC that such

Registration Statement will not be reviewed or will not be subject to further review and (ii) with respect to any additional Registration Statements that may be required to be filed by the Company pursuant to this Agreement, the earlier of the (A) 75 ^th calendar day following the date on which the Company was required to file such additional Registration Statement (or the 105 ^th calendar day after such date in the event that such Registration Statement is subject to review by the SEC) and (B) 4 ^th Business Day after the date the Company is notified (orally or in writing, whichever is earlier) by the SEC that such Registration Statement will not be reviewed or will not be subject to further review.

(e) “ Filing Deadline ” means (i) with respect to the initial Registration Statement required to be filed pursuant to Section 2(a), the 60 ^th calendar day after the Closing Date and (ii) with respect to any additional Registration Statements that may be required to be filed by the Company pursuant to this Agreement, the date on which the Company was required to file such additional Registration Statement pursuant to the terms of this Agreement.

(f) “ Investor ” means Buyer or any transferee or assignee of any Registrable Securities or Warrants, as applicable, to whom Buyer assigns its rights under this Agreement and who agrees to become bound by the provisions of this Agreement in accordance with Section 9 and any transferee or assignee thereof to whom a transferee or assignee of any Registrable Securities or Warrants, as applicable, assigns its rights under this Agreement and who agrees to become bound by the provisions of this Agreement in accordance with Section 9.

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

(h) “ register ,” “ registered ,” and “ registration ” refer to a registration effected by preparing and filing one or more Registration Statements in compliance with the 1933 Act and pursuant to Rule 415 and the declaration of effectiveness of such Registration Statement(s) by the SEC.

(i) “ Registrable Securities ” means (i) the Common Shares, (ii) the Warrant Shares and (iii) any capital stock of the Company issued or issuable with respect to the Common Shares, the Warrant Shares or the Warrants, including, without limitation, (1) as a result of any stock split, stock dividend, recapitalization, exchange or similar event or otherwise and (2) shares of capital stock of the Company into which the shares of Common Stock are converted or exchanged and shares of capital stock of a Successor Entity (as defined in the Warrants) into which the shares of Common Stock are converted or exchanged, in each case, without regard to any limitations on exercise of the Warrants.

(j) “ Registration Statement ” means a registration statement or registration statements of the Company filed under the 1933 Act covering Registrable Securities.

(k) “ Required Investors ” means the holders of at least 66 2/3% of the Registrable Securities.

(l) “ Required Registration Amount ” means the sum of (i) the Common Shares issued and (ii) the maximum number of Warrant Shares issued and issuable pursuant to the

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Warrants as of the Trading Day (as defined in the Warrants) immediately preceding the applicable date of determination (without taking into account any limitations on the exercise of the Warrants set forth therein), all subject to adjustment as provided in Section 2(c).

(m) “ Rule 144 ” means Rule 144 promulgated by the SEC under the 1933 Act, as such rule may be amended from time to time, or any other similar or successor rule or regulation of the SEC that may at any time permit the Investors to sell securities of the Company to the public without registration.

(n) “ Rule 415 ” means Rule 415 promulgated by the SEC under the 1933 Act, as such rule may be amended from time to time, or any other similar or successor rule or regulation of the SEC providing for offering securities on a continuous or delayed basis.

(o) “ SEC ” means the United States Securities and Exchange Commission or any successor thereto.

(a) Mandatory Registration . The Company shall prepare and, as soon as practicable, but in no event later than the Filing Deadline, file with the SEC an initial Registration Statement on Form S-3 covering the resale of all of the Registrable Securities provided that such initial Registration Statement shall register for resale at least the number of shares of Common Stock equal to the Required Registration Amount as of the date such Registration Statement is initially filed with the SEC, provided further that if Form S-3 is unavailable for such a registration, the Company shall use such other form as is required by Section 2(b). Such initial Registration Statement, and each other Registration Statement required to be filed pursuant to the terms of this Agreement, shall contain (except if otherwise directed by the Required Investors) the “ Selling Stockholders ” and “ Plan of Distribution ” sections in substantially the form attached hereto as Exhibit B , unless otherwise required by Staff (as defined below) comments. The Company shall use commercially reasonable efforts to have such initial Registration Statement, and each other Registration Statement required to be filed pursuant to the terms of this Agreement, declared effective by the SEC as soon as practicable, but in no event later than the applicable Effectiveness Deadline for such Registration Statement.

(b) Ineligibility to Use Form S-3 . In the event that Form S-3 is not available for the registration of the resale of Registrable Securities hereunder, the Company shall use commercially reasonable efforts to (i) register the resale of the Registrable Securities on another appropriate form and (ii) undertake to register the resale of the Registrable Securities on Form S-3 as soon as such form is available, provided that the Company shall maintain the effectiveness of all Registration Statements then in effect and the availability for use of each prospectus contained therein until such time as a Registration Statement on Form S-3 covering the resale of all the Registrable Securities has been declared effective by the SEC and the prospectus contained therein is available for use.

(c) Sufficient Number of Shares Registered . In the event the number of shares available under any Registration Statement is insufficient to cover all of the Registrable Securities required to be covered by such Registration Statement or an Investor’s allocated

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portion of the Registrable Securities pursuant to Section 2(e), the Company shall amend such Registration Statement (if permissible), or file with the SEC a new Registration Statement (on the short form available therefor, if applicable), or both, so as to cover at least the Required Registration Amount as of the Trading Day immediately preceding the date of the filing of such amendment or new Registration Statement, in each case, as soon as practicable, but in any event not later than fifteen (15) days after the necessity therefor arises (but taking account of any Staff position with respect to the date on which the Staff will permit such amendment to the Registration Statement and/or such new Registration Statement (as the case may be) to be filed with the SEC). The Company shall use its commercially reasonable efforts to cause such amendment to such Registration Statement and/or such new Registration Statement (as the case may be) to become effective as soon as practicable following the filing thereof with the SEC, but in no event later than the applicable Effectiveness Deadline for such Registration Statement. For purposes of the foregoing provision, the number of shares available under a Registration Statement shall be deemed “insufficient to cover all of the Registrable Securities” if at any time the number of shares of Common Stock available for resale under the applicable Registration Statement is less than the product determined by multiplying (i) the Required Registration Amount as of such time by (ii) 0.90. The calculation set forth in the foregoing sentence shall be made without regard to any limitations on exercise of the Warrants (and such calculation shall assume that the Warrants are then fully exercisable for shares of Common Stock at the then-prevailing applicable Exercise Price).

(d) Offering . Notwithstanding anything to the contrary contained in this Agreement, in the event the staff of the SEC (the “ Staff ”) or the SEC seeks to characterize any offering pursuant to a Registration Statement filed pursuant to this Agreement as constituting an offering of securities by, or on behalf of, the Company, or in any other manner, such that the Staff or the SEC do not permit such Registration Statement to become effective and used for resales in a manner that does not constitute such an offering and that permits the continuous resale at the market by the Investors participating therein (or as otherwise may be acceptable to each Investor) without being named therein as an “underwriter,” then the Company shall reduce the number of shares to be included in such Registration Statement by all Investors until such time as the Staff and the SEC shall so permit such Registration Statement to become effective as aforesaid. In making such reduction, the Company shall reduce the number of shares to be included by all Investors on a pro rata basis (based upon the number of Registrable Securities otherwise required to be included for each Investor) unless the inclusion of shares by a particular Investor or a particular set of Investors are resulting in the Staff or the SEC’s “by or on behalf of the Company” offering position, in which event the shares held by such Investor or set of Investors shall be the only shares subject to reduction (and if by a set of Investors on a pro rata basis by such Investors or on such other basis as would result in the exclusion of the least number of shares by all such Investors). In addition, in the event that the Staff or the SEC requires any Investor seeking to sell securities under a Registration Statement filed pursuant to this Agreement to be specifically identified as an “underwriter” in order to permit such Registration Statement to become effective, and such Investor does not consent to being so named as an underwriter in such Registration Statement, then, in each such case, the Company shall reduce the total number of Registrable Securities to be registered on behalf of such Investor, until such time as the Staff or the SEC does not require such identification or until such Investor accepts such identification and the manner thereof. Any reduction pursuant to this paragraph will first reduce all securities that are not Registrable Securities, if any such

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securities are permitted by the Required Holders to be included in accordance with the terms of this Agreement. In the event of any reduction in Registrable Securities pursuant to this paragraph, an affected Investor shall have the right to require, upon delivery of a written request to the Company signed by such Investor, the Company to file a registration statement within thirty (30) days of such request (subject to any restrictions imposed by Rule 415 or required by the Staff or the SEC) for resale by such Investor in a manner acceptable to such Investor, and the Company shall following such request cause to be and keep effective such registration statement in the same manner as otherwise contemplated in this Agreement for registration statements hereunder, in each case until such time as: (i) all Registrable Securities held by such Investor have been registered and sold pursuant to an effective Registration Statement in a manner acceptable to such Investor or (ii) all Registrable Securities may be resold by such Investor without restriction (including, without limitation, volume limitations) pursuant to Rule 144 (taking account of any Staff position with respect to “affiliate” status) and without the need for current public information required by Rule 144(c)(1) (or Rule 144(i)(2), if applicable) or (iii) such Investor agrees to be named as an underwriter in any such Registration Statement in a manner acceptable to such Investor as to all Registrable Securities held by such Investor and that have not theretofore been included in a Registration Statement under this Agreement (it being understood that the special demand right under this sentence may be exercised by an Investor multiple times and with respect to limited amounts of Registrable Securities in order to permit the resale thereof by such Investor as contemplated above).

(e) Allocation of Registrable Securities . The initial number of Registrable Securities included in any Registration Statement and any increase in the number of Registrable Securities included therein shall be allocated pro rata among the Investors based on the number of Registrable Securities held by each Investor at the time such Registration Statement covering such initial number of Registrable Securities or increase thereof is declared effective by the SEC. In the event that an Investor sells or otherwise transfers any of such Investor’s Registrable Securities, each transferee or assignee (as the case may be) that becomes an Investor shall be allocated a pro rata portion of the then-remaining number of Registrable Securities included in such Registration Statement for such transferor or assignee (as the case may be). Any shares of Common Stock included in a Registration Statement and which remain allocated to any Person which ceases to hold any Registrable Securities covered by such Registration Statement shall be allocated to the remaining Investors, pro rata based on the number of Registrable Securities then held by such Investors which are covered by such Registration Statement.

The Company shall use commercially reasonable efforts to effect the registration of the Registrable Securities in accordance with the intended method of disposition thereof, and, pursuant thereto, the Company shall have the following obligations:

(a) The Company shall promptly prepare and file with the SEC a Registration Statement with respect to all the Registrable Securities (but in no event later than the applicable Filing Deadline) and use commercially reasonable efforts to cause such Registration Statement to become effective as soon as practicable after such filing (but in no event later than the Effectiveness Deadline). Subject to Allowable Grace Periods, the Company shall keep each Registration Statement effective (and the prospectus contained therein available for use) pursuant

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to Rule 415 for resales by the Investors on a delayed or continuous basis at then-prevailing market prices (and not fixed prices) at all times until the earlier of (i) the date as of which all of the Investors may sell all of the Registrable Securities required to be covered by such Registration Statement (disregarding any reduction pursuant to Section 2(d)) without restriction pursuant to Rule 144 (including, without limitation, volume restrictions) and without the need for current public information required by Rule 144(c)(1) (or Rule 144(i)(2), if applicable) or (ii) the date on which the Investors shall have sold all of the Registrable Securities covered by such Registration Statement (the “ Registration Period ”). Notwithstanding anything to the contrary contained in this Agreement, the Company shall ensure that, when filed and at all times while effective, each Registration Statement (including, without limitation, all amendments and supplements thereto) and the prospectus (including, without limitation, all amendments and supplements thereto) used in connection with such Registration Statement (1) shall not contain any 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 the case of prospectuses, in the light of the circumstances in which they were made) not misleading and (2) will disclose (whether directly or through incorporation by reference to other SEC filings to the extent permitted) all material information regarding the Company and its securities. The Company shall submit to the SEC, within five (5) Business Days after the Company learns that no review of a particular Registration Statement will be made by the Staff or that the Staff has no further comments on a particular Registration Statement (as the case may be) a request for acceleration of effectiveness of such Registration Statement to a time and date not later than forty-eight (48) hours after the submission of such request.

(b) The Company shall prepare and file with the SEC such amendments (including, without limitation, post-effective amendments) and supplements to each Registration Statement and the prospectus used in connection with each such Registration Statement, which prospectus is to be filed pursuant to Rule 424 promulgated under the 1933 Act, as may be necessary to keep each such Registration Statement effective at all times during the Registration Period for such Registration Statement, and, during such period, comply with the provisions of the 1933 Act with respect to the disposition of all Registrable Securities of the Company required to be covered by such Registration Statement until such time as all of such Registrable Securities shall have been disposed of in accordance with the intended methods of disposition by the seller or sellers thereof as set forth in such Registration Statement. In the case of amendments and supplements to any Registration Statement which are required to be filed pursuant to this Agreement (including, without limitation, pursuant to this Section 3(b)) by reason of the Company filing a report on Form 10-Q or Form 10-K or any analogous report under the Securities Exchange Act of 1934, as amended (the “ 1934 Act ”), the Company shall have incorporated such report by reference into such Registration Statement, if applicable, or shall file such amendments or supplements with the SEC on the same day on which the 1934 Act report is filed which created the requirement for the Company to amend or supplement such Registration Statement.

(c) The Company shall promptly furnish to each Investor whose Registrable Securities are included in any Registration Statement, without charge, (i) after the same is prepared and filed with the SEC, at least one (1) copy of each Registration Statement and any amendment(s) and supplement(s) thereto, including, without limitation, financial statements and schedules, all documents incorporated therein by reference, if requested by an Investor, all

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exhibits and each preliminary prospectus, (ii) upon the effectiveness of each Registration Statement, ten (10) copies of the prospectus included in such Registration Statement and all amendments and supplements thereto (or such other number of copies as such Investor may reasonably request from time to time) and (iii) such other documents, including, without limitation, copies of any preliminary or final prospectus, as such Investor may reasonably request from time to time in order to facilitate the disposition of the Registrable Securities owned by such Investor.

(d) The Company shall notify each Investor in writing of the happening of any event, as promptly as practicable after becoming aware of such event, as a result of which the prospectus included in a Registration Statement, as then in effect, includes an untrue statement of a material fact or omission to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading (provided that in no event shall such notice contain any material, non-public information regarding the Company or any of its Subsidiaries), and, subject to Section 3(p), promptly prepare a supplement or amendment to such Registration Statement and such prospectus contained therein to correct such untrue statement or omission and deliver ten (10) copies of such supplement or amendment to each Investor (or such other number of copies as such Investor may reasonably request). The Company shall also promptly notify each Investor in writing (i) when a prospectus or any prospectus supplement or post-effective amendment has been filed, when a Registration Statement or any post-effective amendment has become effective (notification of such effectiveness shall be delivered to each Investor by facsimile or e-mail on the same day of such effectiveness and by overnight mail), and when the Company receives written notice from the SEC that a Registration Statement or any post-effective amendment will be reviewed by the SEC, (ii) of any request by the SEC for amendments or supplements to a Registration Statement or related prospectus or related information, (iii) of the Company’s reasonable determination that a post-effective amendment to a Registration Statement would be appropriate; and (iv) of the receipt of any request by the SEC or any other federal or state governmental authority for any additional information relating to the Registration Statement or any amendment or supplement thereto or any related prospectus. The Company shall respond as promptly as practicable to any comments received from the SEC with respect to each Registration Statement or any amendment thereto (it being understood and agreed that the Company’s response to any such comments shall be delivered to the SEC no later than ten (10) Business Days after the receipt thereof).

(e) The Company shall (i) use commercially reasonable efforts to prevent the issuance of any stop order or other suspension of effectiveness of each Registration Statement or the use of any prospectus contained therein, or the suspension of the qualification, or the loss of an exemption from qualification, of any of the Registrable Securities for sale in any jurisdiction and, if such an order or suspension is issued, to obtain the withdrawal of such order or suspension at the earliest possible moment and (ii) notify each Investor who holds Registrable Securities of the issuance of such order and the resolution thereof or its receipt of actual notice of the initiation or threat of any proceeding for such purpose.

(f) If any Investor may be required under applicable securities law to be described in any Registration Statement as an underwriter and such Investor consents to so being named an underwriter, at the request of any Investor, the Company shall furnish to such Investor, on the

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date of the effectiveness of such Registration Statement and thereafter from time to time on such dates as an Investor may reasonably request (i) a letter, dated such date, from the Company’s independent certified public accountants in form and substance as is customarily given by independent certified public accountants to underwriters in an underwritten public offering, addressed to the Investors, and (ii) an opinion, dated as of such date, of counsel representing the Company for purposes of such Registration Statement, in form, scope and substance as is customarily given in an underwritten public offering, addressed to the Investors.

(g) If any Investor may be required under applicable securities law to be described in any Registration Statement as an underwriter and such Investor consents to so being named an underwriter, upon the written request of such Investor, the Company shall make available for inspection by (i) such Investor, (ii) legal counsel for such Investor and (iii) one (1) firm of accountants or other agents retained by such Investor (collectively, the “ Inspectors ”), all pertinent financial and other records, and pertinent corporate documents and properties of the Company (collectively, the “ Records ”), 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, each Inspector shall agree in writing to hold in strict confidence and not to make any disclosure (except to such Investor) or use of any Record or other information which the Company’s board of directors determines in good faith to be confidential, and of which determination the Inspectors are so notified, unless (1) the disclosure of such Records is necessary to avoid or correct a misstatement or omission in any Registration Statement or is otherwise required under the 1933 Act, (2) the release of such Records is ordered pursuant to a final, non-appealable subpoena or order from a court or government body of competent jurisdiction, or (3) the information in such Records has been made generally available to the public other than by disclosure in violation of this Agreement or any other Transaction Document (as defined in the Securities Purchase Agreements). Such Investor agrees that it shall, upon learning that disclosure of such Records is sought in or by a court or governmental body of competent jurisdiction or through other means, give prompt notice to the Company and allow the Company, at its expense, to undertake appropriate action to prevent disclosure of, or to obtain a protective order for, the Records deemed confidential. Nothing herein (or in any other confidentiality agreement between the Company and such Investor, if any) shall be deemed to limit any Investor’s ability to sell Registrable Securities in a manner which is otherwise consistent with applicable laws and regulations.

(h) The Company shall hold in confidence and not make any disclosure of information concerning an Investor 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 or is otherwise required to be disclosed in such Registration Statement pursuant to the 1933 Act, (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 Transaction Document. The Company agrees that it shall, upon learning that disclosure of such information concerning an Investor is sought in or by a court or governmental body of competent jurisdiction or through other means, give prompt written notice to such Investor and allow such Investor, at such Investor’s expense, to undertake appropriate action to prevent disclosure of, or to obtain a protective order for, such information.

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(i) Without limiting any obligation of the Company under the Securities Purchase Agreements, the Company shall use commercially reasonable efforts either to (i) cause all of the Registrable Securities covered by each Registration Statement to be listed on each securities exchange on which securities of the same class or series issued by the Company are then listed, if any, if the listing of such Registrable Securities is then permitted under the rules of such exchange, (ii) secure designation and quotation of all of the Registrable Securities covered by each Registration Statement on the OTC Bulletin Board, or (iii) if, despite the Company’s commercially reasonable efforts to satisfy the preceding clauses (i) or (ii) the Company is unsuccessful in satisfying the preceding clauses (i) or (ii), without limiting the generality of the foregoing, to use commercially reasonable efforts to arrange for at least two market makers to register with the Financial Industry Regulatory Authority (“ FINRA ”) as such with respect to such Registrable Securities. In addition, the Company shall cooperate with each Investor and any broker or dealer through which any such Investor proposes to sell its Registrable Securities in effecting a filing with FINRA pursuant to FINRA Rule 5110 as requested by such Investor. The Company shall pay all fees and expenses in connection with satisfying its obligations under this Section 3(i).

(j) The Company shall cooperate with the Investors who hold Registrable Securities being offered and, to the extent applicable, facilitate the timely preparation and delivery of certificates (not bearing any restrictive legend) representing the Registrable Securities to be offered pursuant to a Registration Statement and enable such certificates to be in such denominations or amounts (as the case may be) as the Investors may reasonably request from time to time and registered in such names as the Investors may request.

(k) If requested by an Investor, the Company shall as soon as practicable after receipt of notice from such Investor and subject to Section 3(p) hereof, (i) incorporate in a prospectus supplement or post-effective amendment such information as an Investor reasonably requests to be included therein relating to the sale and distribution of Registrable Securities, including, without limitation, information with respect to the number of Registrable Securities being offered or sold, the purchase price being paid therefor and any other terms of the offering of the Registrable Securities to be sold in such offering; (ii) make all required filings of such prospectus supplement or post-effective amendment after being notified of the matters to be incorporated in such prospectus supplement or post-effective amendment; and (iii) supplement or make amendments to any Registration Statement or prospectus contained therein if reasonably requested by an Investor holding any Registrable Securities.

(l) The Company shall use commercially reasonable efforts to cause the Registrable Securities covered by a Registration Statement to be registered with or approved by such other governmental agencies or authorities as may be necessary to consummate the disposition of such Registrable Securities.

(m) The Company shall make generally available to its security holders as soon as practical, but not later than ninety (90) days after the close of the period covered thereby, an earnings statement (in form complying with, and in the manner provided by, the provisions of Rule 158 under the 1933 Act) covering a twelve-month period beginning not later than the first day of the Company’s fiscal quarter next following the applicable Effective Date of each Registration Statement.

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(n) The Company shall otherwise use commercially reasonable efforts to comply with all applicable rules and regulations of the SEC in connection with any registration hereunder.

(o) Within one (1) Business Day after a Registration Statement which covers Registrable Securities is declared effective by the SEC, the Company shall deliver, and shall cause legal counsel for the Company to deliver, to the transfer agent for such Registrable Securities (with copies to the Investors whose Registrable Securities are included in such Registration Statement) confirmation that such Registration Statement has been declared effective by the SEC in the form attached hereto as Exhibit A .

(p) Notwithstanding anything to the contrary herein (but subject to the last sentence of this Section 3(p)), at any time after the Effective Date of a particular Registration Statement, the Company may delay the disclosure of material, non-public information concerning the Company or any of its Subsidiaries the disclosure of which at the time is not, in the good faith opinion of the board of directors of the Company, in the best interest of the Company and, in the opinion of counsel to the Company, otherwise required (a “ Grace Period ”), provided that the Company shall promptly notify the Investors in writing of the (i) existence of material, non-public information giving rise to a Grace Period (provided that in each such notice the Company shall not disclose the content of such material, non-public information to any of the Investors) and the date on which such Grace Period will begin and (ii) date on which such Grace Period ends, provided further that (I) no Grace Period shall exceed fifteen (15) consecutive Trading Days and during any three hundred sixty five (365) day period all such Grace Periods shall not exceed an aggregate of forty (40) Trading Days, and (II) the first day of any Grace Period must be at least five (5) Trading Days after the last day of any prior Grace Period (each, an “ Allowable Grace Period ”). For purposes of determining the length of a Grace Period above, such Grace Period shall begin on and include the date the Investors receive the notice referred to in clause (i) above and shall end on and include the later of the date the Investors receive the notice referred to in clause (ii) above and the date referred to in such notice. The provisions of Section 3(e) hereof shall not be applicable during the period of any Allowable Grace Period. Upon expiration of each Grace Period, the Company shall again be bound by the first sentence of Section 3(d) with respect to the information giving rise thereto unless such material, non-public information is no longer applicable. Notwithstanding anything to the contrary contained in this Section 3(p), the Company shall cause its transfer agent to deliver unlegended shares of Common Stock to a transferee of an Investor in accordance with the terms of the Securities Purchase Agreements in connection with any sale of Registrable Securities with respect to which such Investor has entered into a contract for sale, and delivered a copy of the prospectus included as part of the particular Registration Statement to the extent applicable, prior to such Investor’s receipt of the notice of a Grace Period and for which the Investor has not yet settled.

(q) The Company shall use commercially reasonable efforts to maintain eligibility for use of Form S-3 (or any successor form thereto) for the registration of the resale of all the Registrable Securities.

(a) At least three (3) Business Days prior to the first anticipated filing date of each Registration Statement, the Company shall notify each Investor in writing of the information the

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Company requires from each such Investor with respect to such Registration Statement. It shall be a condition precedent to the obligations of the Company to complete the registration pursuant to this Agreement with respect to the Registrable Securities (and the timing therefor) of a particular Investor that such Investor shall furnish 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 required to effect and maintain the effectiveness of the registration of such Registrable Securities and shall execute such documents in connection with such registration as the Company may reasonably request.

(b) Each Investor, by such Investor’s acceptance of the Registrable Securities, agrees to cooperate with the Company as reasonably requested by the Company in connection with the preparation and filing of each Registration Statement hereunder, unless such Investor has notified the Company in writing of such Investor’s election to exclude all of such Investor’s Registrable Securities from such Registration Statement.

(c) Each Investor agrees that, upon receipt of any notice from the Company of the happening of any event of the kind described in Section 3(e) or the first sentence of 3(d) (including the existence of a Grace Period), such Investor will immediately discontinue disposition of Registrable Securities pursuant to any Registration Statement(s) covering such Registrable Securities until such Investor’s receipt of the copies of the supplemented or amended prospectus contemplated by Section 3(e) or the first sentence of Section 3(d) or receipt of notice that no supplement or amendment is required. Notwithstanding anything to the contrary in this Section 4(c), the Company shall cause its transfer agent to deliver unlegended shares of Common Stock to a transferee of an Investor in accordance with the terms of the Securities Purchase Agreements in connection with any sale of Registrable Securities with respect to which such Investor has entered into a contract for sale prior to the Investor’s receipt of a notice from the Company of the happening of any event of the kind described in Section 3(e) or the first sentence of Section 3(d) and for which such Investor has not yet settled.

(d) Each Investor covenants and agrees that it will comply with the prospectus delivery requirements of the 1933 Act as applicable to it in connection with sales of Registrable Securities pursuant to a Registration Statement.

All reasonable expenses, other than underwriting discounts and commissions, incurred in connection with registrations, filings or qualifications pursuant to Sections 2 and 3, including, without limitation, all registration, listing and qualifications fees, printers and accounting fees, FINRA filing fees (if any) and fees and disbursements of counsel for the Company shall be paid by the Company.

(a) To the fullest extent permitted by law, the Company will, and hereby does, indemnify, hold harmless and defend each Investor and each of its directors, officers, shareholders, members, partners, employees, agents, advisors, representatives (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding the

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lack of such title or any other title) and each Person, if any, who controls such Investor within the meaning of the 1933 Act or the 1934 Act and each of the directors, officers, shareholders, members, partners, employees, agents, advisors, representatives (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding the lack of such title or any other title) of such controlling Persons (each, an “ Indemnified Person ”), against any claims, damages, liabilities, judgments, fines, penalties, charges, costs (including, without limitation, court costs, reasonable attorneys’ fees and costs of defense and investigation), amounts paid in settlement or expenses, joint or several, (collectively, “ Claims ”) incurred in defending any action, claim, suit, inquiry, proceeding, investigation or appeal taken from the foregoing by or before any court or governmental, administrative or other regulatory agency, body or the SEC, (“ Indemnified Damages ”), to which any of them may become subject insofar as such Claims arise out of or are based upon: (i) any untrue statement or alleged untrue statement of a material fact in a Registration Statement or any post-effective amendment thereto, or the omission or alleged omission to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (ii) any untrue statement or alleged untrue statement of a material fact contained in any preliminary prospectus if used prior to the effective date of such Registration Statement, or contained in the final prospectus (as amended or supplemented, if the Company files any amendment thereof or supplement thereto with the SEC) or the omission or alleged omission to state therein any material fact necessary to make the statements made therein, in light of the circumstances under which the statements therein were made, not misleading or (iii) any violation or alleged violation by the Company of the 1933 Act, the 1934 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 (the matters in the foregoing clauses (i) through (iii) being, collectively, “ Violations ”). Subject to Section 6(c), the Company shall reimburse the Indemnified Persons, promptly as such expenses are incurred and are due and payable, for any legal fees or other reasonable expenses incurred by them in connection with investigating or defending any such Claim. Notwithstanding anything to the contrary contained herein, the indemnification agreement contained in this Section 6(a): (1) shall not apply to a Claim by an Indemnified Person arising out of or based upon a Violation which occurs in reliance upon and in conformity with information furnished to the Company by such Indemnified Person for use in connection with the preparation of such Registration Statement or any such amendment thereof or supplement thereto; (2) shall not be available to a particular Indemnified Person to the extent such Claim is based on a failure of such Indemnified Person or its affiliates to timely deliver or to cause to be timely delivered the prospectus made available by the Company (to the extent applicable), including, without limitation, a corrected prospectus, if such prospectus or corrected prospectus was timely made available by the Company pursuant to Section 3(c) and then only if, and to the extent that, following the receipt of the corrected prospectus no grounds for such Claim would have existed; (3) shall not be available to a particular Investor or its affiliates with respect to a particular sale by such Investor of Registrable Securities pursuant to a Registration Statement only if such sale was made by such Investor in violation of its obligations under Section 4(c) of this Agreement; and (4) shall not apply to amounts paid in settlement of any Claim if such settlement is effected without the prior written consent of the Company, which consent shall not be unreasonably withheld or delayed. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of the Indemnified Person and shall survive the transfer of any of the Registrable Securities by any of the Investors pursuant to Section 9.

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(b) In connection with any Registration Statement in which an Investor is participating, such Investor agrees to severally and not jointly indemnify, hold harmless and defend, to the same extent and in the same manner as is set forth in Section 6(a), the Company, each of its directors, each of its officers and each Person, if any, who controls the Company within the meaning of the 1933 Act or the 1934 Act (each, an “ Indemnified Party ”), against any Claim or Indemnified Damages to which any of them may become subject, under the 1933 Act, the 1934 Act or otherwise, insofar as such Claim or Indemnified Damages arise out of or are based upon any Violation, in each case, to the extent, and only to the extent, that such Violation occurs in reliance upon and in conformity with information furnished to the Company by such Investor expressly for use in connection with such Registration Statement; and, subject to Section 6(c) and the below provisos in this Section 6(b), such Investor will reimburse an Indemnified Party any legal or other expenses reasonably incurred by such Indemnified Party in connection with defending any such Claim; provided, however, the indemnity agreement contained in this Section 6(b) and the agreement with respect to contribution contained in Section 7 shall not apply to amounts paid in settlement of any Claim if such settlement is effected without the prior written consent of such Investor, which consent shall not be unreasonably withheld or delayed, provided further that such Investor shall be liable under this Section 6(b) for only that amount of a Claim or Indemnified Damages as does not exceed the net proceeds to such Investor as a result of the applicable sale of Registrable Securities pursuant to such Registration Statement. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of such Indemnified Party and shall survive the transfer of any of the Registrable Securities by any of the Investors pursuant to Section 9.

(c) Promptly after receipt by an Indemnified Person or Indemnified Party (as the case may be) under this Section 6 of notice of the commencement of any action or proceeding (including, without limitation, any governmental action or proceeding) involving a Claim, such Indemnified Person or Indemnified Party (as the case may be) shall, if a Claim in respect thereof is to be made against any indemnifying party under this Section 6, deliver to the indemnifying party a written notice of the commencement thereof, and the indemnifying party shall have the right to participate in, and, to the extent the indemnifying party so desires, jointly with any other indemnifying party similarly noticed, to assume control of the defense thereof with counsel mutually satisfactory to the indemnifying party and the Indemnified Person or the Indemnified Party (as the case may be); provided, however, an Indemnified Person or Indemnified Party (as the case may be) shall have the right to retain its own counsel with the fees and expenses of such counsel to be paid by the indemnifying party if: (i) the indemnifying party has agreed in writing to pay such fees and expenses; (ii) the indemnifying party shall have failed promptly to assume the defense of such Claim and to employ counsel reasonably satisfactory to such Indemnified Person or Indemnified Party (as the case may be) in any such Claim; or (iii) the named parties to any such Claim (including, without limitation, any impleaded parties) include both such Indemnified Person or Indemnified Party (as the case may be) and the indemnifying party, and such Indemnified Person or such Indemnified Party (as the case may be) shall have been advised by counsel that a conflict of interest is likely to exist if the same counsel were to represent such Indemnified Person or such Indemnified Party and the indemnifying party, in which case, if such Indemnified Person or such Indemnified Party (as the case may be) notifies the indemnifying party in writing that it elects to employ separate counsel at the expense of the indemnifying party, then 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 further that in the case of

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clause (iii) above the indemnifying party shall not be responsible for the reasonable fees and expenses of more than one (1) separate legal counsel for such Indemnified Person or Indemnified Party (as the case may be). The Indemnified Party or Indemnified Person (as the case may be) shall reasonably cooperate with the indemnifying party in connection with any negotiation or defense of any such action or Claim by the indemnifying party and shall furnish to the indemnifying party all information reasonably available to the Indemnified Party or Indemnified Person (as the case may be) which relates to such action or Claim. The indemnifying party shall keep the Indemnified Party or Indemnified Person (as the case may be) reasonably apprised at all times as to the status of the defense or any settlement negotiations with respect thereto. No indemnifying party shall be liable for any settlement of any action, claim or proceeding effected without its prior written consent; provided, however, the indemnifying party shall not unreasonably withhold, delay or condition its consent. No indemnifying party shall, without the prior written consent of the Indemnified Party or Indemnified Person (as the case may be), consent to entry of any judgment or enter into any settlement or other compromise which does not include as an unconditional term thereof the giving by the claimant or plaintiff to such Indemnified Party or Indemnified Person (as the case may be) of a release from all liability in respect to such Claim or litigation, and such settlement shall not include any admission as to fault on the part of the Indemnified Party. Following indemnification as provided for hereunder, the indemnifying party shall be subrogated to all rights of the Indemnified Party or Indemnified Person (as the case may be) with respect to all third parties, firms or corporations relating to the matter for which indemnification has been made. The failure to deliver written notice to the indemnifying party within a reasonable time of the commencement of any such action shall not relieve such indemnifying party of any liability to the Indemnified Person or Indemnified Party (as the case may be) under this Section 6, except to the extent that the indemnifying party is materially and adversely prejudiced in its ability to defend such action.

(d) No Person involved in the sale of Registrable Securities who is guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933 Act) in connection with such sale shall be entitled to indemnification from any Person involved in such sale of Registrable Securities who is not guilty of fraudulent misrepresentation.

(e) The indemnification required by this Section 6 shall be made by periodic payments of the amount thereof during the course of the investigation or defense, as and when bills are received or Indemnified Damages are incurred.

(f) The indemnity and contribution agreements contained herein shall be in addition to (i) any cause of action or similar right of the Indemnified Party or Indemnified Person against the indemnifying party or others, and (ii) any liabilities the indemnifying party may be subject to pursuant to the law.

To the extent any indemnification by an indemnifying party is prohibited or limited by law, the indemnifying party agrees to make the maximum contribution with respect to any amounts for which it would otherwise be liable under Section 6 to the fullest extent permitted by law; provided, however: (i) no contribution shall be made under circumstances where the maker would not have been liable for indemnification under the fault standards set

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forth in Section 6 of this Agreement, (ii) no Person involved in the sale of Registrable Securities which Person is guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933 Act) in connection with such sale shall be entitled to contribution from any Person involved in such sale of Registrable Securities who was not guilty of fraudulent misrepresentation; and (iii) contribution by any seller of Registrable Securities shall be limited in amount to the amount of net proceeds received by such seller from the applicable sale of such Registrable Securities pursuant to such Registration Statement. Notwithstanding the provisions of this Section 7, no Investor shall be required to contribute, in the aggregate, any amount in excess of the amount by which the net proceeds actually received by such Investor from the applicable sale of the Registrable Securities subject to the Claim exceeds the amount of any damages that such Investor has otherwise been required to pay, or would otherwise be required to pay under Section 6(b), by reason of such untrue or alleged untrue statement or omission or alleged omission.

With a view to making available to the Investors the benefits of Rule 144, the Company agrees to:

(a) make and keep public information available, as those terms are understood and defined in Rule 144;

(b) file with the SEC in a timely manner all reports and other documents required of the Company under the 1933 Act and the 1934 Act so long as the Company remains subject to such requirements (it being understood and agreed that nothing herein shall limit any obligations of the Company under the Securities Purchase Agreements) and the filing of such reports and other documents is required for the applicable provisions of Rule 144; and

(c) furnish to each Investor so long as such Investor owns Registrable Securities, promptly upon request, (i) a written statement by the Company, if true, that it has complied with the reporting, submission and posting requirements of Rule 144 and the 1934 Act, (ii) a copy of the most recent annual or quarterly report of the Company and such other reports and documents so filed by the Company with the SEC if such reports are not publicly available via EDGAR, and (iii) such other information as may be reasonably requested to permit the Investors to sell such securities pursuant to Rule 144 without registration.

All or any portion of the rights under this Agreement shall be assignable by each Investor to any transferee or assignee (as the case may be) of all or any portion of such Investor’s Registrable Securities or Warrants, with the Company’s reasonable consent, if: (i) such Investor agrees in writing with such transferee or assignee (as the case may be) to assign all or any portion of such rights, and a copy of such agreement is furnished to the Company within a reasonable time after such transfer or assignment (as the case may be); (ii) the Company is, within a reasonable time after such transfer or assignment (as the case may be), furnished with written notice of (a) the name and address of such transferee or assignee (as the case may be), and (b) the securities with respect to which such registration rights are being transferred or

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assigned (as the case may be); (iii) immediately following such transfer or assignment (as the case may be) the further disposition of such securities by such transferee or assignee (as the case may be) is restricted under the 1933 Act or applicable state securities laws if so required; (iv) at or before the time the Company receives the written notice contemplated by clause (ii) of this sentence such transferee or assignee (as the case may be) agrees in writing with the Company to be bound by all of the provisions contained herein; (v) such transfer or assignment (as the case may be) shall have been made in accordance with the applicable requirements of the applicable Securities Purchase Agreement and the Warrants (as the case may be); and (vi) such transfer or assignment (as the case may be) shall have been conducted in accordance with all applicable federal and state securities laws.

Provisions of this Agreement may be amended only with the written consent of the Company and the Required Investors. Any amendment effected in accordance with this Section 10 shall be binding upon each Investor and the Company, provided that no such amendment shall be effective to the extent that it (a) applies to less than all of the holders of Registrable Securities, (b) imposes any obligation or liability on any Investor without such Investor’s prior written consent (which may be granted or withheld in such Investor’s sole discretion) or (c) applies retroactively. No waiver shall be effective unless it is in writing and signed by an authorized representative of the waiving party, provided that the Required Investors (in a writing signed by all of the Required Investors) may waive any provision of this Agreement, and any waiver of any provision of this Agreement made in conformity with the provisions of this Section 10 shall be binding on each Investor, provided that no such waiver shall be effective to the extent that it (1) applies to less than all the Investors (unless a party gives a waiver as to itself only) or (2) imposes any obligation or liability on any Investor without such Investor’s prior written consent (which may be granted or withheld in such Investor’s sole discretion). No consideration shall be offered or paid to any Person to amend or consent to a waiver or modification of any provision of this Agreement unless the same consideration also is offered to all of the parties to this Agreement.

(a) Solely for purposes of this Agreement, a Person is deemed to be a holder of Registrable Securities whenever such Person owns, or is deemed to own, of record such Registrable Securities. If the Company receives conflicting instructions, notices or elections from two or more Persons with respect to the same Registrable Securities, the Company shall act upon the basis of instructions, notice or election received from such record owner of such Registrable Securities.

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(b) Any notices, consents, waivers or other communications required or permitted to be given under the terms of this Agreement must be in writing and will be deemed to have been delivered: (i) upon receipt, when delivered personally; (ii) upon receipt, when sent by facsimile (provided confirmation of transmission is mechanically or electronically generated and kept on file by the sending party); (iii) by electronic mail (provided confirmation of transmission is electronically generated and kept on file by the sending party); or (iv) one (1) Business Day after deposit with a nationally recognized overnight delivery service with next day delivery specified, in each case, properly addressed to the party to receive the same. The addresses and facsimile numbers for such communications shall be:

If to the Company:

ARCA biopharma, Inc.

8001 Arista Place, Suite 430

Broomfield, Colorado 80021

E-mail: pat.wheeler@arcabiopharma.com

Facsimile:  (720) 940-2457

Attention:  Chief Financial Officer

With a copy (for informational purposes only) to:

Cooley LLP

380 Interlocken Crescent, Suite 900

Broomfield, CO 80021

E-mail: fassettbd@cooley.com

Facsimile:  (720) 566-4099

Attention:  Brent D. Fassett

If to the Transfer Agent:

Computershare Trust Company, N.A.

350 Indiana Street, Suite 800

Golden, CO 80401

E-mail: kathy.kinard@computershare.com

Facsimile:  (303) 262-0632

Attention:  Kathy Kinard

If to a Buyer, to its address, facsimile number or electronic mail address (as the case may be) set forth on such Buyer’s signature page to its Securities Purchase Agreement, or to such other address and/or facsimile number and/or to the attention of such other Person as the recipient party has specified by written notice given to each other party five (5) days prior to the effectiveness of such change. Written confirmation of receipt (A) given by the recipient of such notice, consent, waiver or other communication, (B) mechanically or electronically generated by the sender’s facsimile machine or electronic mail transmission containing the time, date and recipient facsimile number or electronic mail address or (C) provided by a courier or overnight courier service shall be rebuttable evidence of personal service, receipt by facsimile or receipt from a nationally recognized overnight delivery service in accordance with clause (i), (ii) or (iii) above, respectively.

(c) Failure of any party to exercise any right or remedy under this Agreement or otherwise, or delay by a party in exercising such right or remedy, shall not operate as a waiver thereof. The Company and each Investor acknowledge and agree that irreparable damage would

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occur in the event that any of the provisions of this Agreement were not performed in accordance with their specific terms or were otherwise breached. It is accordingly agreed that each party hereto shall be entitled to an injunction or injunctions to prevent or cure breaches of the provisions of this Agreement by any other party hereto and to enforce specifically the terms and provisions hereof (without the necessity of showing economic loss and without any bond or other security being required), this being in addition to any other remedy to which any party may be entitled by law or equity.

(d) All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be governed by 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 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 TO, 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.

(e) This Agreement, the other Transaction Documents, the schedules and exhibits attached hereto and thereto and the instruments referenced herein and therein constitute the entire agreement among the parties hereto and thereto solely with respect to the subject matter hereof and thereof. There are no restrictions, promises, warranties or undertakings, other than those set forth or referred to herein and therein. This Agreement, the other Transaction Documents, the schedules and exhibits attached hereto and thereto and the instruments referenced herein and therein supersede all prior agreements and understandings among the parties hereto solely with respect to the subject matter hereof and thereof.

(f) Subject to compliance with Section 9 (if applicable), this Agreement shall inure to the benefit of and be binding upon the permitted successors and assigns of each of the parties hereto. This Agreement is not for the benefit of, nor may any provision hereof be enforced by, any Person, other than the parties hereto, their respective permitted successors and assigns and the Persons referred to in Sections 6 and 7 hereof.

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(g) The headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning hereof. Unless the context clearly indicates otherwise, each pronoun herein shall be deemed to include the masculine, feminine, neuter, singular and plural forms thereof. The terms “including,” “includes,” “include” and words of like import shall be construed broadly as if followed by the words “without limitation.” The terms “herein,” “hereunder,” “hereof” and words of like import refer to this entire Agreement instead of just the provision in which they are found.

(h) This Agreement may be executed in two or more counterparts, all of which 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. In the event that any signature is delivered by facsimile transmission or by an e-mail which contains a portable document format (.pdf) file of an executed signature page, such signature page 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 signature page were an original thereof.

(i) Each party shall do and perform, or cause to be done and performed, all such further acts and things, and shall execute and deliver all such other agreements, certificates, instruments and documents as any other party may reasonably request in order to carry out the intent and accomplish the purposes of this Agreement and the consummation of the transactions contemplated hereby.

(j) The language used in this Agreement will be deemed to be the language chosen by the parties to express their mutual intent and no rules of strict construction will be applied against any party. Notwithstanding anything to the contrary set forth in Section 10, terms used in this Agreement but defined in the other Transaction Documents shall have the meanings ascribed to such terms on the Closing Date in such other Transaction Documents unless otherwise consented to in writing by each Investor.

[ signature pages follow ]

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IN WITNESS WHEREOF , Buyer and the Company have caused their respective signature page to this Registration Rights Agreement to be duly executed as of the date first written above.

IN WITNESS WHEREOF , Buyer and the Company have caused their respective signature page to this Registration Rights Agreement to be duly executed as of the date first written above.

EXHIBIT A

FORM OF NOTICE OF EFFECTIVENESS

OF REGISTRATION STATEMENT

            , 20    

Ladies and Gentlemen:

Reference is made to the Subscription Agreement (the “ Securities Purchase Agreement ”) entered into by and between ARCA biopharma, Inc. (the “ Company ”) and the buyer named therein ( the “ Holder ”) pursuant to which the Company issued to the Holder shares of the Company’s common stock, $0.001 par value per share (the “ Common Stock ”), and warrants exercisable for shares of Common Stock (the “ Warrants ”). Pursuant to the Securities Purchase Agreement, the Company also has entered into a Registration Rights Agreement with the Holder (the “ Registration Rights Agreement ”) pursuant to which the Company agreed, among other things, to register the Registrable Securities (as defined in the Registration Rights Agreement), including the shares of Common Stock issuable upon exercise of the Warrants, under the Securities Act of 1933, as amended (the “ 1933 Act ”). In connection with the Company’s obligations under the Registration Rights Agreement, on                  , 20    , the Company filed a Registration Statement on Form S-3 (File No. 333-            ) (the “ Registration Statement ”) with the Securities and Exchange Commission (the “ SEC ”) relating to the Registrable Securities which names the Holder as a selling stockholder thereunder.

In connection with the foregoing, we advise you that a member of the SEC’s staff has advised us by telephone that the SEC has entered an order declaring the Registration Statement effective under the 1933 Act at [ENTER TIME OF EFFECTIVENESS] on [ENTER DATE OF EFFECTIVENESS].

EXHIBIT B

SELLING STOCKHOLDERS

The shares of common stock being offered by the selling stockholders are those issued to the selling stockholders and those issuable to the selling stockholders upon exercise of the warrants. For additional information regarding the issuance of the common stock and the warrants, see “Private Placement of Common Stock and Warrants” above. We are registering the shares of common stock in order to permit the selling stockholders to offer the shares for resale from time to time. Except for the ownership of the common stock and the warrants issued pursuant to (i) the Subscription Agreements and (ii) the Subscription Agreements entered into on             , 2012, the selling stockholders have not had any material relationship with us within the past three years.

The table below lists the selling stockholders and other information regarding the beneficial ownership (as determined under Section 13(d) of the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder) of the shares of common stock held by each of the selling stockholders. The second column lists the number of shares of common stock beneficially owned by the selling stockholders, based on their respective ownership of shares of common stock and warrants, as of             , 20    , assuming exercise of the warrants held by each such selling stockholder on that date but taking account of any limitations on exercise set forth therein.

The third column lists the shares of common stock being offered by this prospectus by the selling stockholders and does not take into account any limitations on exercise of the warrants set forth therein.

In accordance with the terms of a registration rights agreement with the holders of the common stock and the warrants, this prospectus generally covers the resale of the sum of (i) the shares of common stock issued to the selling stockholders and (ii) the maximum number of shares of common stock issuable upon exercise of the warrants determined as if the outstanding warrants were exercised in full (without regard to any limitations on exercise contained therein) as of the trading day immediately preceding the date this registration statement was initially filed with the SEC. Because the exercise price of the warrants may be adjusted, the number of shares that will actually be issued may be more or less than the number of shares being offered by this prospectus. The fourth column assumes the sale of all of the shares offered by the selling stockholders pursuant to this prospectus.

Under the terms of the warrants, a selling stockholder may not exercise the warrants to the extent (but only to the extent) such selling stockholder or any of its affiliates would beneficially own a number of shares of our common stock which would exceed 4.9%. The beneficial ownership limitation under the warrants will not apply if the holder beneficially owned, immediately following the issuance of such warrants, in excess of 4.9% of the shares of common stock then outstanding. The number of shares in the second column reflects these limitations. The selling stockholders may sell all, some or none of their shares in this offering. See “Plan of Distribution.”

PLAN OF DISTRIBUTION

We are registering the shares of common stock issued to the selling stockholders and the shares of common stock issuable upon exercise of the warrants to permit the resale of these shares of common stock by the selling stockholders from time to time after the date of this prospectus. We will not receive any of the proceeds from the sale by the selling stockholders of the shares of common stock. We will bear all fees and expenses incident to our obligation to register the shares of common stock.

The selling stockholders may sell all or a portion of the shares of common stock held by them and offered hereby from time to time directly or through one or more underwriters, broker-dealers or agents. If the shares of common stock are sold through underwriters or broker-dealers, the selling stockholders will be responsible for underwriting discounts or commissions or agent’s commissions. The shares of common stock may be sold in one or more transactions at fixed prices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale or at negotiated prices. These sales may be effected in transactions, which may involve crosses or block transactions, pursuant to one or more of the following methods:

The selling stockholders may also sell shares of common stock under Rule 144 promulgated under the Securities Act of 1933, as amended, if available, rather than under this prospectus. In addition, the selling stockholders may transfer the shares of common stock by other means not described in this prospectus. If the selling stockholders effect such transactions by selling shares of common stock to or through underwriters, broker-dealers or agents, such underwriters, broker-dealers or agents may receive commissions in the form of discounts, concessions or commissions from the selling stockholders or commissions from purchasers of the shares of common stock for whom they may act as agent or to whom they may sell as principal (which discounts, concessions or commissions as to particular underwriters, broker-dealers or agents may be in excess of those customary in the types of transactions involved). In connection with sales of the shares of common stock or otherwise, the selling stockholders may enter into hedging transactions with broker-dealers, which may in turn engage in short sales of the shares of common stock in the course of hedging in positions they assume. The selling stockholders may also sell shares of common stock short and deliver shares of common stock covered by this prospectus to close out short positions and to return borrowed shares in connection with such short sales. The selling stockholders may also loan or pledge shares of common stock to broker-dealers that in turn may sell such shares.

The selling stockholders may pledge or grant a security interest in some or all of the warrants or shares of common stock owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the shares of common stock from time to time pursuant to this prospectus or any 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 stockholders also may transfer and donate the shares of common stock in other circumstances in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

To the extent required by the Securities Act and the rules and regulations thereunder, the selling stockholders and any broker-dealer participating in the distribution of the shares of common stock may be deemed to be “underwriters” within the meaning of the Securities Act, and any commission paid, or any discounts or concessions allowed to, any such broker-dealer may be deemed to be underwriting commissions or discounts under the Securities Act. At the time a particular offering of the shares of common stock is made, a prospectus supplement, if required, will be distributed, which will set forth the aggregate amount of shares of common stock being offered and the terms of the offering, including the name or names of any broker-dealers or agents, any discounts, commissions and other terms constituting compensation from the selling stockholders and any discounts, commissions or concessions allowed or re-allowed or paid to broker-dealers.

Under the securities laws of some states, the shares of common stock may be sold in such states only through registered or licensed brokers or dealers. In addition, in some states the

shares of common stock may not be sold unless such shares have been registered or qualified for sale in such state or an exemption from registration or qualification is available and is complied with.

There can be no assurance that any selling stockholder will sell any or all of the shares of common stock registered pursuant to the registration statement, of which this prospectus forms a part.

The selling stockholders and any other person participating in such distribution will be subject to applicable provisions of the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder, including, without limitation, to the extent applicable, Regulation M of the Exchange Act, which may limit the timing of purchases and sales of any of the shares of common stock by the selling stockholders and any other participating person. To the extent applicable, Regulation M may also restrict the ability of any person engaged in the distribution of the shares of common stock to engage in market-making activities with respect to the shares of common stock. All of the foregoing may affect the marketability of the shares of common stock and the ability of any person or entity to engage in market-making activities with respect to the shares of common stock.

We will pay all expenses of the registration of the shares of common stock pursuant to the registration rights agreement, estimated to be $[        ] in total, including, without limitation, Securities and Exchange Commission filing fees and expenses of compliance with state securities or “blue sky” laws; provided, however, a selling stockholder will pay all underwriting discounts and selling commissions, if any. We will indemnify the selling stockholders against liabilities, including some liabilities under the Securities Act in accordance with the registration rights agreements or the selling stockholders will be entitled to contribution. We may be indemnified by the selling stockholders against civil liabilities, including liabilities under the Securities Act that may arise from any written information furnished to us by the selling stockholder specifically for use in this prospectus, in accordance with the related registration rights agreements or we may be entitled to contribution.

Once sold under the registration statement, of which this prospectus forms a part, the shares of common stock will be freely tradable in the hands of persons other than our affiliates.

Exhibit 10.3

AMENDMENT TO THE REGISTRATION RIGHTS AGREEMENT

This Amendment to that certain Registration Rights Agreement dated October 25, 2012 (the “Registration Rights Agreement”) is made and entered into this 18 ^th day of December, 2012 between ARCA biopharma, Inc., a Delaware corporation (the “Company”), and the other parties identified on the signature page hereto (the “Buyers”).

WITNESSETH

W HEREAS , in connection with the purchase of common stock in the Company by the Buyers, the parties entered into the Registration Rights Agreement, pursuant to which the Company agreed to prepare and file a Registration Statement with the SEC not later than the Filing Deadline, and to have the Registration Statement declared effective by the SEC not later than the Effectiveness Deadline, as those terms are defined in the Registration Rights Agreement;

W HEREAS , the parties agree that it is in their mutual interest to extend the Filing Deadline for an additional 60 days and the Effectiveness Deadline for an additional 90 days;

N OW , T HEREFORE , in consideration of the premises and the mutual covenants contained herein and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company and each of the Buyers hereby agree as follows:

I. AMENDMENT

The Filing Deadline with respect to the filing of the Initial Registration Statement, as defined in Section 1(e) of the Registration Rights Agreement, shall be extended by an additional 60 calendar days, or 120 calendar days after the Closing Date. The Effectiveness Deadline with respect to the Initial Registration Statement, as defined in Section 1(d) of the Registration Rights Agreement, shall be extended for an additional 90 calendar days, such that it shall be the earlier of the (A) 180 ^th calendar day after the Closing Date and (B) 4 ^th Business Day after the date the Company is notified (orally or in writing, whichever is earlier) by the SEC that such Registration Statement will not be reviewed or will not be subject to further review.

II. MISCELLANEOUS

2.1 Except as expressly amended pursuant to this Amendment, all other provisions of the Registration Rights Agreement shall remain unchanged and in full force and effect.

2.2 This Amendment shall be governed by and construed in accordance with the laws of the State of New York.

2.3 Any capitalized terms not defined herein shall have the meanings as set forth in the Registration Rights Agreement.

IN WITNESS WHEREOF , the parties hereto have caused this Amendment to be duly executed by their respective authorized signatories.