**Execution Copy**

 

**STOCK PURCHASE AGREEMENT**

STOCK PURCHASE AGREEMENT (this            “Agreement”) dated as of            June 29, 2007 (the “Closing            Date”), by and among the selling stockholders            identified inSchedule Ihereto (the            “Selling Stockholders”),            PSS WORLD MEDICAL, INC. (“PSS”), a Florida corporation (the            “Buyer”) and            athenahealth, Inc. a Delaware corporation (the            “Company”).

**W            I T N E S S E T H:**

WHEREAS, the Selling Stockholders desire to sell to the Buyer and the            Buyer desires to purchase from the Selling Stockholders, in the aggregate, 493,157            shares (the “Series C            Shares”) of the Series C Convertible Preferred            Stock, par value $0.01 per share of the Company (the            “Series C Preferred            Stock”);

WHEREAS, the Selling Stockholders desire to sell to the Buyer and the            Buyer desires to purchase from the Selling Stockholders, in the aggregate, 862,164            shares (the “Series D            Shares”) of the Series D Convertible Preferred            Stock, par value $0.01 per share of the Company (the            “Series D Preferred            Stock”); and

WHEREAS, the Selling Stockholders desire to sell to the Buyer and the            Buyer desires to purchase from the Selling Stockholders, in the aggregate, 115,268            shares (the “Series E            Shares” and collectively with the Series C Shares and            Series D Shares the “Preferred            Shares”) of the Series E Convertible Preferred            Stock, par value $0.01 per share of the Company (the            “Series E Preferred            Stock” and collectively with the Series C Preferred            Stock and Series D Preferred Stock the “Preferred            Stock”).

**NOW, THEREFORE**, in consideration of the            premises and the mutual covenants contained in this Agreement and for other good and            valuable consideration, the receipt and sufficiency of which is hereby acknowledged,            the parties hereto agree as follows:

**ARTICLE I - PURCHASE AND SALE**

1.01              Purchase and Sale. Upon the terms and            subject to the conditions of this Agreement, on the Closing Date, the Selling            Stockholders severally and not jointly shall sell to the Buyer, and the Buyer shall            purchase from each Selling Stockholder that number of Series C Shares, Series D Shares            and Series E Shares set forth opposite its name onSchedule Iattached hereto for the            purchase price set forth opposite its name on such schedule under the column heading            “Aggregate Purchase Price to Selling Stockholder.” The price per share for            each Preferred Share is $ 15.30 (the “Per Share Purchase            Price”).

1.02              Closing. On the Closing Date and at the            closing of the transactions contemplated hereby (the            “Closing”) the following            actions shall take place:

(a)              Each Selling Stockholder shall deliver or cause to be delivered to Buyer            and the Company, as applicable (i) a certificate or certificates for the Preferred            Shares duly endorsed or accompanied by irrevocable stock transfer powers substantially            in the form attached

hereto            asExhibit Aand (ii) such            other instruments of transfer and documents as Buyer or the Company may reasonably            request.

(b)             The Buyer shall deliver or cause to be delivered to the Selling            Stockholders or the Company, as applicable (i) the amount set forth opposite such            Selling Stockholder’s name under the heading “Aggregate Purchase Price to            Selling Stockholder” as set forth onSchedule Iattached hereto, by wire            transfer of immediately available funds in accordance with the wire instructions set            forth onSchedule I, (ii) an            instrument of accession to that certain Second Amended and Restated Voting Agreement            dated as of April 16, 2004 by and between the Company and the parties thereto, as            amended, (the “Voting            Agreement”) and that certain Second Amended and            Restated Investor Rights Agreement dated as of April 16, 2004 by and between the            Company and the parties thereto, as amended, (the            “Investor Rights            Agreement”) in substantially the form attached hereto            asExhibit Band (iii) such other            documents as the Company or Selling Stockholders may reasonably request. Each Selling            Stockholder will provide their wire transfer instructions in writing to the Buyer at            least 24 hours before the Closing.

(c)             The Company, upon delivery by the Buyer to the Company of the items            referenced in (b), shall promptly, and without further requirements on the Buyers, the            Selling Stockholders or otherwise, issue to the Buyers certificates representing the            Preferred Shares in the name of Buyer and in the amounts set forth opposite its name            onSchedule IIattached            hereto.

(d)             The Company and the Buyer shall enter into a Board Observer Rights            Agreement in the form attached hereto asExhibit            C.

(e)             The Buyer shall enter into a Lock-Up Agreement in the form attached            hereto asExhibit Dwith the            managing underwriters of the Company’s proposed initial public offering (the            “Underwriters”).

(f)             The Underwriters shall release the Selling Shareholders from lock-up            agreements previously executed by them, to the extent required for the sale of the            Preferred Shares hereunder.

(g)             The Buyer shall pay the expenses set forth in Section 5.10            hereof.

1.03              Closing Time. Theinitial purchase and sale            of the Preferred Shares shall take place remotely via the exchange of documents and            signatures, at 10:00 a.m., on June 29, 2007, or at such other time and place as the            Company, the Selling Stockholders and Buyer mutually agree upon, orally or in writing.            In the event there is more than one closing, the term            “Closing” shall apply to            each such closing unless otherwise specified.

**ARTICLE II - REPRESENTATIONS AND WARRANTIES**

**OF THE SELLING STOCKHOLDERS**

Each Selling Stockholder, severally and not jointly, represents and            warrants to the Buyer and the Company that the statements contained in this Article II            as to itself are correct and complete as of the date of this Agreement.

2.01             Title to and Validity of Shares. The            Selling Stockholder has good and valid title to and has the power to sell the Preferred            Shares, free and clear of any lien, pledge, security interest, options, charges,            encumbrances or other claim or defect of title whatsoever (collectively,            “Liens”) and, upon            purchase and payment therefor and delivery to the Buyer thereof in accordance with the            terms of this Agreement, the Buyer will obtain good and valid title to such Preferred            Shares free and clear of any Lien or adverse claim other than any Liens contained in            agreements between the Company and the Selling Shareholders entered into in connection            with the purchase of the Preferred Shares .

2.02              Organization; Authority; Binding Agreement.            The Selling Stockholder is duly organized, validly existing and in good standing under            the laws of the jurisdiction of its organization. The Selling Stockholder has the legal            power, right and authority to enter into and perform this Agreement, and to perform its            obligations hereunder. The Selling Stockholder has received all authorizations and            approvals required by law and under its charter and by-laws or other organizational            documents to enter into this Agreement and to sell, transfer and deliver all of the            Preferred Shares being sold by such Selling Stockholder hereunder and to comply with            its other obligations hereunder. This Agreement has been duly executed and delivered            and constitutes a valid, legal binding and enforceable agreement of such Selling            Stockholder.

2.03              No Conflicts; No Further Consents, etc.            Neither the execution, delivery and performance by the Selling Stockholder of this            Agreement nor the consummation by such Selling Stockholder of the transactions            contemplated hereby conflicts with such Selling Stockholder’s organizational            documents, or any instrument, agreement, governmental authorization, or order to which            the Preferred Shares are subject or by which such Selling Stockholder is a party or is            bound [lockup waiver]. No consent, approval, authorization or other order of, or            registration or filing with, any court or other governmental authority or agency, is            required for the consummation by the Selling Stockholders of the transactions            contemplated by this Agreement. No consent, approval or waiver is required under any            instrument or agreement to which the Preferred Shares are subject or by which such            Selling Stockholder is a party or is bound in connection with the consummation by the            Selling Stockholder of the transactions contemplated by this Agreement. The Selling            Stockholder has complied with, or conformed to, in all respects, the provisions of each            instrument or agreement to which the Preferred Shares are subject or by which such            Selling Stockholder is a party or is bound, in connection with the consummation of the            transactions contemplated by this Agreement.[lockup waiver]

2.04              Release. There are no representations,            warranties, agreements or undertakings of the Buyer with respect to the transactions            contemplated by this Agreement other than those set forth in this Agreement. The            Selling Stockholder acknowledges that it has performed its own analysis of the price at            which it would agree to sell the Preferred Shares being sold by such Selling            Stockholder and that the Company could effect at any time an initial public offering or            sale which generates liquidity for its stockholders at valuations on a per share basis            far in excess of the Original Per Share Purchase Price. Such Selling Stockholder hereby            and forever fully releases and discharges the Buyer, the Company and its respective            directors, officers, trustees, shareholders, employees, beneficiaries, attorneys,            agents, representatives, partners, limited partners, investors, affiliates, successors            and assigns (collectively, the “Buyer Released            Parties” and the            “Company Released            Parties,” respectively) of and from any and all suits,            demands, obligations, liabilities, claims and causes of action, contingent or            otherwise, of every kind and

nature, at law and in equity, whether asserted, unasserted, absolute,            contingent, known or unknown, which such Selling Stockholder or its directors,            officers, trustees, shareholders, employees, beneficiaries, attorneys, agents,            representatives, partners, limited partners, investors, affiliates, successors and/or            assigns may have against the Buyer Released Parties or the Company Released Parties, or            any of them, to the extent arising from the transactions contemplated by this            Agreement, except for claims arising under, and subject to the limitations contained            in, the express terms of this Agreement, including any inaccuracies in the            representations and warranties of the Buyer set forth in this Agreement.

**ARTICLE III - REPRESENTATIONS AND WARRANTIES OF THE            BUYER**

The Buyer represents and warrants to the Selling Stockholders and the            Company that the statements contained in this Article III are true and complete as of            the date of this Agreement.

3.01              Organization; Authority; Binding Agreement.            Buyer is duly organized, validly existing and in good standing under the laws of the            jurisdiction of its organization. Buyer has the legal power, right and authority to            eater into and perform this Agreement, and to perform its obligations hereunder. Buyer            has received all authorizations and approvals required by law and under its charter and            by-laws or other organizational documents to enter into this Agreement and to purchase            all of the Preferred Shares being acquired by Buyer hereunder and to comply with its            other obligations hereunder. This Agreement has been duly executed and delivered and            constitutes a valid, legal binding and enforceable agreement of Buyer.

3.02              No Conflicts; No Further Consent, etc.            Neither the execution, delivery and performance by Buyer of this Agreement nor the            consummation by Buyer of the transactions contemplated hereby conflicts with            Buyer’s organizational documents, or any governmental authorization or order by            which Buyer is a party or is bound. No consent, approval, authorization or other order            of, or registration or filing with, any court or other governmental authority or            agency, is required for the consummation by Buyer of the transactions contemplated by            this Agreement.

3.03              Purchasing for Own Account. Buyer is            acquiring the Preferred Shares being purchased by Buyer for investment purposes only            and is not acquiring the Preferred Shares being purchased by Buyer with a view to, or            for sale in connection with, the distribution of the Preferred Shares being purchased            by Buyer within the meaning of the Securities Act of 1933, as amended (the            “Securities            Act”).

3.04              Accredited Investor. Buyer is an accredited            investor as such term is defined in Rule 501(a) of Regulation D under the            Securities Act, and has reasonable access to, and has had sufficient opportunity to            carefully review and analyze, all material information about the Company’s            business, financial condition, operations and value that Buyer believes to be relevant            to its purchase of the Preferred Shares. Buyer is sophisticated and experienced in            evaluating the merits and risks involving an investment in the Company’s            securities and the particulars of the purchase of the Preferred Shares. Buyer has the            ability to bear the economic risks of its purchase of the Preferred Shares and has been            able to obtain all information required in making an informed decision regarding its            investment.

3.05              Release. There are no representations,            warranties, agreements or undertakings of the Selling Stockholders with respect to the            transactions contemplated by this Agreement other than those set forth in this            Agreement. Buyer further represents and warrants that, in executing and delivering this            Agreement, it has not relied on any statement or representation made by any legal            counsel or investment advisor to or other agent of any Selling Stockholder. Buyer            hereby and forever fully releases and discharges the Company Released Parties and the            Selling Stockholders and their respective directors, officers, trustees, shareholders,            employees, beneficiaries, attorneys, agents, representatives, partners, limited            partners, investors, affiliates, successors and assigns (collectively, the            “Seller Released            Parties”) of and from any and all suits, demands,            obligations, liabilities, claims and causes of action, contingent or otherwise, of            every kind and nature, at law and in equity, whether asserted, unasserted, absolute,            contingent, known or unknown, which Buyer or its directors, officers, trustees,            shareholders, employees, beneficiaries, attorneys, agents, representatives, partners,            limited partners, investors, affiliates, successors and/or assigns may have against the            Seller Released Parties or the Company Released Parties, or any of them, to the extent            arising from the transactions contemplated by this Agreement, except for claims arising            under, and subject to the limitations contained in, the express terms of this            Agreement, including any inaccuracies in the representations and warranties of the            Selling Stockholders set forth in this Agreement.

3.06              Company Participation. Buyer acknowledges            that (i) the offer and sale of the Preferred Shares have been made solely by the            Selling Stockholders, and (ii) the Company is not participating in or recommending the            sale and has made no representation or warranty (and has not authorized the Sellers to            do so on behalf of the Company) regarding the Preferred Shares, or the business            operations or future prospects of the Company.

**ARTICLE IV - AGREEMENTS OF THE COMPANY**,

**SELLING STOCKHOLDERS AND THE BUYERS**

4.01              Consent to Transaction; Transfer of Shares.            The Company hereby irrevocably consents to the sale of the Preferred Shares as            contemplated by this Agreement. The Company and each Selling Stockholder hereby            irrevocably consents to the sale of the Preferred Shares as contemplated in this            Agreement and, solely with respect to the sale of the Preferred Shares to Buyer, hereby            waives any consents, notices or notice periods, rights of first offer, rights of first            refusal and any other limitations upon the transfer of the Preferred Stock to Buyer            contained in any agreement between the Company and any Selling Stockholder (other than            this Agreement).Upon delivery to the Company of stock            certificates representing the Preferred Shares duly enclosed or accompanied, by            irrevocable stock transfer powers substantially in the form attached hereto asExhibit A, the Company shall promptly,            and without further requirements on the Buyer, the Selling Stockholders or otherwise,            issue to the Buyer certificates representing the Preferred Shares in the name of Buyer            and in the amounts set forth opposite its name onSchedule IIattached            hereto.

|   | 4.02 | Change of Control Repurchase                            Right. |
|--------|------|----------------------------------------------------------------|

(a)              Grant. Buyer hereby unconditionally and            irrevocably grants to the each Selling Stockholder the right to repurchase from Buyer            all or a portion of the Seller Shares sold by such Selling Stockholder to Buyer            pursuant to this Agreement, upon a Change of Control of

Buyer            (as defined below) occurring at any time prior to the earlier of (i) December 31, 2010            or (ii) the consummation of the Company’s first underwritten public offering of            its common stock (hereinafter, “Common Stock”) under the Securities Act            (“IPO”) pursuant to            provisions of thisSection 4.02(the            “Change of Control Repurchase            Right”).

(b)              Notice. The Buyer shall give notice of a            Change of Control by mail, postage prepaid, to the Company and each Selling Stockholder            as soon as is practicable prior to the closing of such Change of Control, but in any            event no later than sixty (60) days prior to the closing date of the Change of Control            (the “Change of Control            Notice”). To exercise its Change of Control Repurchase            Right under thisSection 4.02, a            Selling Stockholder must deliver to the Buyer and the Company written notice of its            intention to exercise such repurchase right within thirty (30) days of receipt of the            Change of Control Notice (the “Selling Stockholder            Change of Control Repurchase Notice”).

(c)              Undersubscription. If options to repurchase            the Seller Shares have been exercised by the Selling Stockholders with respect to some            but not all of the Seller Shares by the end of the 30-day period specified in the last            sentence ofSection 4.02(b))(the            “Selling Stockholder Change of Control Notice            Period”), then the Buyer shall, immediately after the            expiration of the Selling Stockholder Change of Control Notice Period, send written            notice (the “Change of Control Undersubscription            Notice”) to the Company and those Selling Stockholders            who fully exercised their Change of Control Repurchase Right within the Selling            Stockholder Change of Control Notice Period (collectively, the            “Change of Control Exercising Selling            Stockholders”). Each Change of Control Exercising            Selling Stockholder shall, subject to the provisions of thisSection 4.02(c), have an additional option            to purchase all or any part of the balance of any such remaining unsubscribed Seller            Shares. To exercise such option, a Change of Control Exercising Selling Stockholder            must deliver to the Buyer and the Company written notice of its intention to exercise            its option to purchase all or any portion of the Seller Shares not purchased pursuant            toSection 4.02(b)within ten (10)            days after the expiration of the Selling Stockholder Change of Control Notice Period            (the “Change of Control Undersubscription Selling            Stockholder Notice Period”) . In the event there are            two or more such Change of Control Exercising Selling Stockholders that choose to            exercise the last-mentioned option for a total number of remaining shares in excess of            the number available, the remaining shares available for purchase under thisSection 4.02(a)shall be allocated to such            Change of Control Exercising Selling Stockholders in manner mutually agreeable to such            Change of Control Exercising Selling Stockholders. If the options to purchase the            remaining shares are exercised in full by the Change of Control Exercising Selling            Stockholders, the Buyer shall immediately notify all of the Change of Control            Exercising Selling Stockholders and the Company of that fact.

(d)              Grant of Secondary Change of Control Repurchase Right to the            Company. Buyer hereby unconditionally and irrevocably grants            to the Company a secondary Change of Control Repurchase Right to purchase all or any            portion of the Seller Shares not purchased by the Selling Stockholders pursuant their            Change of Control Repurchase Right, as provided inSection            4.02(b)andSection            4.02(c)above. To exercise its Change of Control Repurchase            Right under thisSection 4.02, the            Company must deliver written notice of its intention to exercise such repurchase right            within ten (10) days of the expiration of the Change of Control Undersubscription            Selling Stockholder Notice Period. If the option to purchase the remaining

shares            are exercised in full by the Company, the Company shall immediately notify all Buyer            and the Change of Control Exercising Selling Stockholders of that fact.

(e)              Consideration; Closing. The closing of the            repurchase and/or purchase of the Seller Shares by the Selling Stockholders and the            Company, respectively, as the case may be, shall take place, and all payments from the            Selling Stockholders and the Company, as applicable, shall have been delivered to the            Buyer, immediately prior to, and contingent upon, the consummation of the Change of            Control. The consideration to be paid for the Seller Shares shall be the Fair Market            Value (as defined below) of the Seller Shares at the time of the Change of Control.            Immediately prior to, and contingent upon, the consummation of such Change of Control,            the Buyer shall promptly surrender to the Selling Stockholders and the Company, as            applicable, free and clear of any liens or encumbrances, any certificates representing            the Seller Shares being repurchased or purchased, together with a duly executed stock            power for the transfer of such Seller Shares to the Selling Stockholders or the            Company.

|   | (f) | Definitions. |
|--------|-----|--------------|

(i)              “Capital            Stock” means (a) shares of Common Stock and            Preferred Stock (whether now outstanding or hereafter issued in any context),            (b) shares of Common Stock issued or issuable upon conversion of Preferred Stock            and (c) shares of Common Stock issued or issuable upon exercise or conversion, as            applicable, of stock options, warrants or other convertible securities of the            Company.

(ii)              “Change of            Control” means the consummation of (1) the dissolution            or liquidation of the Buyer, (2) the sale of all or substantially all of the            assets of the Buyer on a consolidated basis to an unrelated person or entity, (3) a            merger, reorganization or consolidation in which the outstanding shares of Stock are            converted into or exchanged for securities of the successor entity and the holders of            the Buyer’s outstanding voting power immediately prior to such transaction do not            own at least a majority of the outstanding voting power of the successor entity            immediately upon completion of such transaction, (4) the sale of all or a majority of            the Stock of the Buyer to an unrelated person or entity in a single transaction or a            series of related transactions, or (5) any other transaction or series of related            transactions in which the holders of the Buyer’s outstanding voting power            immediately prior to such transaction do not own at least a majority of the outstanding            voting power of the Buyer or a successor entity immediately upon completion of the            transaction. Notwithstanding the foregoing, a transaction described in this paragraph            shall constitute a Change of Control if, and only if the entity acquiring control of            the Buyer as a result of the transaction is a Company Competitor (as defined            below).

(iii)              “Company            Competitor” means a business, firm or entity that (i)            is, at the time of the Change of Control, listed in the KLAS Enterprises LLC vendor            directory, found at http://www.healthcomputing.com/vendordirectory/ , (or any successor            directory) as a vendor of software or services to the healthcare industry within one or            more the following market segments: ambulatory billing and scheduling, ambulatory EMR,            ambulatory specialty, claims management, outsourced billing and revenue cycle            transformation; and (ii) had sales of such software or services in excess of            $300,000,000

for the fiscal year ending immediately prior to the determination of            whether such entity is a Company Competitor.

(iv)               Fair Market Value” shall be the fair            market value thereof, as collectively determined in good faith by the Buyer, the Change            of Control Exercising Selling Stockholders and/or the Company, as applicable. If such            parties are unable to agree on the value of the Seller Shares, they shall collectively            and unanimously select an independent nationally recognized investment banking firm            (the “Appraiser”) to            determine the Fair Market Value of the Seller Shares and the determination of such            investment banking firm shall be binding upon the parties. In the event the parties are            unable collectively and unanimously select an investment banking firm, each party shall            each select its own nationally-recognized investment banking firm and such firms shall            select a nationally-recognized investment banking firm to determine the value of the            Seller Shares and the determination of this investment banking firm (the            “Alternate Appraiser”)            shall be binding upon the parties hereto. The Buyer, the Change of Control Exercising            Selling Stockholders and/or the Company, as applicable, shall each bear their own costs            and expenses with respect to the investment banking appraisal process described above;            provided that, all fees incurred in connection with use of the Appraiser or the            Alternate Appraiser in accordance with the foregoing, shall be evenly split among the            Buyer, the Change of Control Exercising Selling Stockholders and/or the Company, as            applicable. Notwithstanding anything to the contrary contained herein, the method of            valuation of securities subject to investment letters or other similar restrictions on            free marketability (other than restrictions arising solely by virtue of a            stockholder’s status as an affiliate or former affiliate) shall take into account            an appropriate discount from the market value as determined pursuant to clause (1)            above so as to reflect the approximate fair market value thereof.

|   | 4.03. | Company’s Right of First                            Refusal. |
|--------|-------|--------------------------------------------------------------------|

(a)              Grant. Buyer hereby unconditionally and            irrevocably grants to the Company a Right of First Refusal to purchase all or any            portion of Seller Shares that Buyer may propose to Transfer after December 31, 2010, at            the same price and on the same terms and conditions as those offered to any person to            whom Buyer proposes Transfer Seller Shares (the            “Prospective            Transferee”). Notwithstanding the foregoing, the            Company’s Right of First Refusal in this Section 4.03 shall not apply to            transfers made by Buyer pursuant to the repurchase rights set forth in Section 4.02 and            shall terminate upon the consummation of the IPO.

(b)              Notice. Buyer must deliver a written notice            to the Company not later than forty-five (45) days prior to the consummation of            such proposed Transfer (the “Proposed Transfer            Notice”). Such Proposed Transfer Notice shall contain            the material terms and conditions (including price and form of consideration) of the            proposed Transfer and the identity of the Prospective Transferee. To exercise its Right            of First Refusal under thisSection            4.03, the Company must deliver written notice to Buyer of the            Company’s intention to exercise its Rights of First Refusal with respect to some            or all of the Seller Shares (the “Company Right of First            Refusal Notice”) within fifteen (15) days after            delivery of the Proposed Transfer Notice. In the event of a conflict between this            Agreement and any other agreement that may have been entered into by Buyer with the            Company that contains a preexisting right of first refusal, the Company

and            Buyer acknowledge and agree that the terms of this Agreement shall control and the            preexisting right of first refusal shall be deemed satisfied by compliance withSection 4.03(a)and thisSection 4.03 (b).

(c)              Consideration; Closing. If the            consideration proposed to be paid for the Seller Shares is in property, services or            other non-cash consideration, the fair market value of the consideration shall be as            determined in accordance with the provisions of Section 4.02(f)(iii). If the Company            cannot for any reason pay for the Seller Shares in the same form of non-cash            consideration, the Company may pay the cash value equivalent thereof, as determined in            good faith by the Board of Directors and as set forth in the Company Right of Refusal            Notice. The closing of the purchase of Seller Shares by the Company shall take place,            and all payments from the Company shall have been delivered to Buyer, by the later of            (i) the date specified in the Proposed Transfer Notice as the intended date of the            proposed Transfer and (ii) forty-five (45) days after delivery of the            Proposed Transfer Notice. If any proposed sale or transfer by the Buyer (or its            Affiliate) is not consummated within 45 days after receipt by the Company of the            initial notice thereof, the Buyer (or its Affiliate) may not sell or transfer any            Seller Shares unless it complies in full with each provision of thisSection 4.03. Any Seller Shares purchased            by such proposed transferee shall be deemed held by an Affiliate of the Buyer and            accordingly shall remain subject to the terms of this Agreement. Any Seller Shares not            sold to the proposed transferee shall remain subject to this Agreement.

(d)             Termination. The covenants set forth            inSection 4.03shall terminate and            be of no further force or effect immediately before the consummation of the            IPO.

4.04.              Standstill. Buyer shall not purchase any            securities of the Company prior to December 31, 2010, to the extent that after giving            effect to such purchase, Buyer (together with such Buyer’s Affiliates, and any            other person or entity acting as a group together with Buyer or any of such            Buyer’s Affiliates), would beneficially own in excess of 14.99% of the number of            shares of the Common Stock on an as-converted basis outstanding immediately after            giving effect to such purchase. For purposes of thisSection            4.04, beneficial ownership shall be calculated in accordance            with Section 13(d) of the Securities Exchange Act of 1934 and the rules and regulations            promulgated thereunder. For purposes of thisSection            4.04, in determining the number of outstanding shares of            Common Stock, a Holder may rely on the number of outstanding shares of Common Stock as            reflected in (x) the Company’s most recent Form 10-Q or Form 10-K, as the case            may be, (y) a more recent public announcement by the Company or (z) any other notice by            the Company or the Company’s transfer agent setting forth the number of shares of            Common Stock outstanding. Upon the written or oral request of Buyer, the Company shall            within three trading days confirm orally and in writing to Buyer the number of shares            of Common Stock then outstanding. In any case, the number of outstanding shares of            Common Stock shall be determined after giving effect to the conversion or exercise of            securities of the Company, by Buyer or its affiliates since the date as of which such            number of outstanding shares of Common Stock was reported. ThisSection 4.04shall terminate and be of no            further force and effect immediately upon the earlier of (i) January 1, 2011, (ii) the            first public announcement by an unaffiliated third party of the Buyer (or group of such            parties constituting a “group” for purposes of Section 13(d)(3) of the            Securities Exchange Act of 1934) of its intention to purchase a majority of the Capital            Stock of the Company, or (iii) an unaffiliated third party of the Buyer (or group of            such parties constituting a “group” for purposes of Section 13(d)(3) of the            Securities

Exchange Act of 1934) acquiring more than 14.99% of the outstanding            Capital Stock of the Company.

4.05.              Prohibited Stock Purchase Offer. Prior to            the IPO, Buyer shall not offer to purchase shares of the company’s Capital Stock            from any stockholder without the prior written consent of the Company’s Board of            Directors.

4.06.              Lock Up. Buyer hereby agrees that upon the            request of the Company in connection with a proposed initial public offering of the            Company’s stock, it will execute and deliver to the managing underwriters of such            initial public offering a lock-up agreement substantially in the form ofExhibit Dattached hereto.

4.07.              Stop Transfer Instructions. In order to            enforce the foregoing covenant, the Company may impose stop-transfer instructions with            respect to the shares of Capital Stock of Buyer (and transferees and assignees thereof)            until the end of such restricted period.

4.08              Conversion of Preferred Stock. In the event            of the Company’s IPO (as defined above), the Buyer shall voluntarily convert (or            if requested by the Company consent to having such shares automatically convert) into            shares of the Company’s Common Stock, in any such case, effective as of the            closing of the IPO and as further provided in the Company’s certificate of            incorporation,*provided that*any            such conversion or vote may be contingent upon the conversion of all other shares of            the Company’s Preferred Stock into shares of Common Stock.

**ARTICLE V - MISCELLANEOUS**

5.01.              Notices. All notices and other            communications to any party hereunder shall be in writing and shall be given at the            address listed below such party’s name on the signature page hereto.

5.02.              No Waivers. No failure or delay by either            party in exercising any right, power or privilege hereunder shall operate as a waiver            thereof nor shall any single or partial exercise thereof preclude any other or further            exercise thereof or the exercise of any other right, power or privilege. The rights and            remedies herein provided shall be cumulative and not exclusive of any rights or            remedies provided by law.

5.03.              Governing Law; Venue. This Agreement shall            be construed in accordance with the General Corporation Law of the State of Delaware as            to matters within the scope thereof, and as to all other matters shall be governed by            and construed in accordance with the internal laws of the Commonwealth of            Massachusetts, without regard to its principles of conflicts of law            provisions.

5.04.              Counterparts; Effectiveness. This Agreement            may be signed in any number of counterparts, each of which shall be an original, with            the same effect as if the signatures thereto and hereto were upon the same instrument            This Agreement shall become effective when each party hereto shall have received a            counterpart hereof signed by the other parties hereto.

5.05.              Entire Agreement. This Agreement            constitutes the entire agreement between the Seller and the Buyer with respect to the            subject matter hereof and supersede all prior agreements, understandings and            negotiations, both written and oral, between any of such parties with respect to the            subject matter hereof. And other agreements delivered pursuant.

5.06.              Successors and Assigns; Third Parties. No            party to this Agreement shall convey, assign or otherwise transfer any of its rights or            obligations under this Agreement without the express written consent of the other            parties hereto. This Agreement shall be binding upon and shall inure to the benefit of            the parties hereto and there respective successors and permitted assigns. Subject to            the immediately preceding sentence and except as provided inSection 4.07, this Agreement is not            intended to benefit, and shall not run to the benefit of or be enforceable by, any            other person or entity other than the parties hereto and their permitted successors and            assigns.

5.07.              Legend. Each certificate representing            shares of Transfer Stock held by Buyer or issued to any permitted transferee in            connection with a transfer permitted bySection            4.03hereof shall be endorsed with the following            legend:

THE SALE, PLEDGE, HYPOTHECATION OR TRANSFER OF THE SECURITIES            REPRESENTED BY THIS CERTIFICATE IS SUBJECT TO, AND IN CERTAIN CASES PROHIBITED BY, THE            TERMS AND CONDITIONS OF A CERTAIN STOCK PURCHASE AGREEMENT BY AND AMONG THE            STOCKHOLDER, THE COMPANY AND CERTAIN OTHER HOLDERS OF STOCK OF THE COMPANY. COPIES OF            SUCH AGREEMENT MAY BE OBTAINED UPON WRITTEN REQUEST TO THE SECRETARY OF THE            COMPANY.

Buyer            agrees that the Company may instruct its transfer agent to impose transfer restrictions            on the shares represented by certificates bearing the legend referred to in thisSection 5.07above to enforce the            provisions of this Agreement, and the Company agrees to promptly do so. The legend            shall be removed upon termination of this Agreement at the request of the            holder.

5.08.              Amendments; Waivers. This Agreement may be            modified or amended only by a written agreement signed by all parties. Provisions            hereof may be waived by a party hereto only by an instrument signed by such party. No            delay on the part of any party in exercising any right, power or privilege hereunder            shall operate as a waiver thereof, nor shall any waiver on the part of such party of            any right, power or privilege hereunder operate as a waiver of any other right, power            or privilege hereunder, nor shall any single or partial exercise of any right, power or            privilege hereunder preclude any other or further exercise thereof or the exercise of            any other right, power or privilege hereunder.

5.09.              Survival of Representations and Warranties.            All representations and warranties shall survive the Closing and remain in full force            and effect indefinitely.

5.10.              Expenses. The Buyer agrees to pay on demand            (i) amounts owed to Goldman, Sachs & Co. as advisor to the Company in connection            with this transaction, up to a maximum of $562,000 and (ii) a maximum of $30,000 of the            other reasonable costs and expenses of the

Company and the Selling Stockholders, including reasonable legal fees            and expenses, in connection with the preparation, execution and delivery of this            Agreement, and other instruments and documents to be delivered hereunder, and in            connection with the consummation of the transactions contemplated hereby and thereby.            In connection with such payment, the Company shall provide to the Buyer, on request,            detailed invoices setting forth the fees and expenses so incurred. For the avoidance of            doubt, such fees and expenses shall not include any fees or expenses incurred by the            Company in connection with the preparation or negotiation of the Marketing and Sales            Agreement between the Buyer and the Company.

5.11.              Further Assurances. From and after the date            of this Agreement, upon the request of any Buyer or the Company, the Company, the            Seller, and the Buyers shall execute and deliver such instruments, documents and other            writings as may be reasonably necessary or desirable to confirm, carry out and to            effectuate fully the intent and purposes of this Agreement, the transactions            contemplated in this Agreement and the sale and purchase of the Shares.

[*Signature pages to            follow*]

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

 

COMPANY

 

ATHENAHEALTH, INC.

 

By:_______________________

Name:

Title:

 

BUYER

 

PSS            WORLD MEDICAL, INC.

 

By:_______________________

Name:

Title:

**[Signature Page to Stock Purchase            Agreement]**

 

SELLING STOCKHOLDERS

 

Cardinal Health Partners, L.P.

By:            Cardinal Health Partners Management, LLC, its sole General Partner

 

 

By:            ____________________

Name:            Brandon H. Hull

Title:            Managing Member

 

CHP II,            L.P.

By: CHP            II Management, LLC, its sole General Partner

 

 

By:_____________________

Name:            Brandon H. Hull

Title:            Managing Member

 

**[Signature Page to Stock Purchase Agreement]**

OAK            INVESTMENT PARTNERS IX, L.P.

By: Oak            Associates IX, L.L.C.

Its:            General Partner

 

 

____________________________________

By:

Its:

 

 

OAK IX            AFFILIATES FUND, L.P.

By: Oak            IX Affiliates, L.L.C.

Its:            General Partner

 

 

____________________________________

By:

Its:

 

 

OAK IX            AFFILIATES FUND – A, L.P.

By: Oak            IX Affiliates, L.L.C.

Its:            General Partner

 

 

____________________________________

By:

Its:

 

**[Signature Page to Stock Purchase Agreement]**

Granite            Global Ventures (Q.P.) L.P.

 

By            Granite Global Ventures L.L.C., its General Partner

 

 

| By: ____________________________ |
|----------------------------------|

Name:

Managing Director

 

Granite            Global Ventures L.P.

By            Granite Global Ventures L.L.C., its General Partner

 

 

| By: ____________________________ |
|----------------------------------|

Name:

Managing Director

 

**[Signature Page to Stock Purchase Agreement]**

VENROCK            ASSOCIATES

By:  its General Partner

 

VENROCK            ASSOCIATES II, L.P.

By:  its General Partner

 

VENROCK            ENTREPRENEURS FUND, L.P.

By:  its General Partner, Venrock Management, LLC

 

By:            _________________________________

Bryan            E. Roberts

General            Partner or Member

 

**[Signature Page to Stock Purchase Agreement]**