UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

(Amendment No.     )

Filed by the Registrant   ☑

Filed by a Party other than the Registrant   ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☑ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material under §240.14a-12

ATHENAHEALTH, INC.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check the appropriate box):

December 20, 2018

Dear Fellow Stockholder:

A special meeting of stockholders of athenahealth, Inc., a Delaware corporation (“athenahealth” or the “Company”), will be held on February 7, 2019, at 2:00 P.M. Eastern Time, at our headquarters at 311 Arsenal Street, Watertown, Massachusetts 02472. You are cordially invited to attend. The purpose of the meeting is to consider and vote on proposals relating to the proposed acquisition of athenahealth by May Holding Corp., a Delaware corporation (“Parent”), for $135.00 per share in cash. Parent is an affiliate of Veritas Capital Fund Management, L.L.C. (“Veritas”) and Evergreen Coast Capital (“Evergreen”), and an affiliate of certain entities operating under the name Virence Health (“Virence”). Regardless of whether you plan to attend the meeting, we encourage you to vote your shares by mail, by telephone or through the Internet following the procedures outlined below.

On November 11, 2018, athenahealth entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Parent and May Merger Sub Inc., a Delaware corporation and a direct wholly-owned subsidiary of Parent (“Merger Sub”), providing for, subject to the satisfaction or waiver of specified conditions, the acquisition of athenahealth by Parent at a price of $135.00 per share in cash. Subject to the terms and conditions of the Merger Agreement, Merger Sub will be merged with and into athenahealth (the “Merger”), with athenahealth surviving the merger as a wholly-owned subsidiary of Parent. At the special meeting, athenahealth will ask you to adopt the Merger Agreement.

At the effective time of the Merger (the “Effective Time”), each share of athenahealth common stock issued and outstanding immediately prior to the Effective Time (other than (i) shares owned by Parent, any subsidiary of Parent, Merger Sub or athenahealth, in each case immediately prior to the Effective Time, and (ii) shares held by stockholders who have not voted in favor of the Merger and who have properly and validly perfected their statutory rights of appraisal in respect of such shares in accordance with Section 262 of the Delaware General Corporation Law) will be cancelled, extinguished and automatically converted into the right to receive $135.00 per share in cash, net of any applicable withholding taxes and without interest.

The proxy statement accompanying this letter provides you with more specific information concerning the special meeting, the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement. We encourage you to carefully read the accompanying proxy statement and the copy of the Merger Agreement attached as Annex A to the proxy statement.

The board of directors of athenahealth (the “Board”) carefully reviewed and considered the terms and conditions of the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement. By a unanimous vote, the Board (i) adopted and declared advisable the Merger Agreement and the Merger and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (ii) authorized and approved the execution, delivery and performance of the Merger Agreement and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (iii) determined that the transactions contemplated by the Merger Agreement, including the Merger, are in the best interests of athenahealth and its stockholders, (iv) directed that a proposal to adopt the Merger Agreement be submitted to a vote at a meeting of athenahealth stockholders and (v) recommended that athenahealth stockholders vote for the adoption of the Merger Agreement. Accordingly, the Board unanimously recommends a vote “FOR” the proposal to adopt the Merger Agreement.

Your vote is important. Whether or not you plan to attend the special meeting and regardless of the number of shares you own, your careful consideration of, and vote on, the proposal to adopt the Merger Agreement is important, and we encourage you to vote promptly. The Merger cannot be completed unless the Merger Agreement is adopted by stockholders holding at least a majority of the outstanding shares of athenahealth common stock entitled to vote on such matter. The failure to vote will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement.

After reading the accompanying proxy statement, please make sure to vote your shares promptly by completing, signing and dating the accompanying proxy card and returning it in the enclosed prepaid envelope or by voting by telephone or through the Internet by following the instructions on the accompanying proxy card. Instructions regarding all three methods of voting are provided on the proxy card. If you hold shares through an account with a bank, broker, trust or other nominee, please follow the instructions you receive from it to vote your shares.

Thank you in advance for your continued support and your consideration of this matter.

Neither the United States Securities and Exchange Commission nor any state securities regulatory agency has approved or disapproved the Merger, passed upon the merits or fairness of the Merger or passed upon the adequacy or accuracy of the disclosure in this document. Any representation to the contrary is a criminal offense.

The accompanying proxy statement is dated December 20, 2018 and is first being mailed to athenahealth stockholders on or about December 21, 2018.

ATHENAHEALTH, INC.

311 Arsenal Street

Watertown, MA 02472

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

To Be Held on February 7, 2019

To the Stockholders of athenahealth, Inc.:

A special meeting of stockholders of athenahealth, Inc. (“athenahealth” or the “Company”) will be held on February 7, 2019, at 2:00 P.M. Eastern Time, at our headquarters at 311 Arsenal Street, Watertown, Massachusetts 02472, for the following purposes:

Stockholders of record at the close of business on December 18, 2018 are entitled to notice of, and to vote at, the special meeting and any adjournments or postponements thereof.

For more information concerning the special meeting, the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement, please review the accompanying proxy statement and the copy of the Merger Agreement attached as Annex A to the proxy statement.

The board of directors of athenahealth (the “Board”) carefully reviewed and considered the terms and conditions of the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement. By a unanimous vote, the Board (i) adopted and declared advisable the Merger Agreement and the Merger and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (ii) authorized and approved the execution, delivery and performance of the Merger Agreement and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (iii) determined that the transactions contemplated by the Merger Agreement, including the Merger, are in the best interests of athenahealth and its stockholders, (iv) directed that a proposal to adopt the Merger Agreement be submitted to a vote at a meeting of athenahealth stockholders and (v) recommended that athenahealth stockholders vote for the adoption of the Merger Agreement.

The Board unanimously recommends that at the special meeting you vote “FOR” the proposal to adopt the Merger Agreement, “FOR” the approval, by a non-binding advisory vote, of the compensation that may be paid or become payable to athenahealth’s named executive officers that is based on or otherwise relates to the Merger and “FOR” the proposal to adjourn the special meeting if necessary or appropriate, including to solicit additional proxies.

To assure that your shares are represented at the special meeting, regardless of whether you plan to attend the special meeting in person, please fill in your vote, sign and mail the enclosed proxy card as soon as possible. We have enclosed a return envelope, which requires no postage if mailed in the United States. Alternatively, you may vote by telephone or through the Internet. Instructions regarding each of the methods of voting are provided on the enclosed proxy card. If you are voting by telephone or through the Internet, then your voting instructions must be received by 11:59 p.m. Eastern Time on the day before the special meeting. Your proxy is being solicited by the Board.

If you have any questions about the Merger or how to submit your proxy, or if you need additional copies of this proxy statement or the enclosed proxy card or voting instructions, please call our proxy solicitor, Innisfree, toll-free at (877) 717-3925 for stockholders or (212) 750-5833 for bankers and brokers.

If you fail to return your proxy, vote by telephone or through the Internet or attend the special meeting in person, your shares will not be counted for purposes of determining whether a quorum is present at the special meeting and will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement.

Watertown, Massachusetts

December 20, 2018

Please Vote—Your Vote is Important

TABLE OF CONTENTS

i

ii

Annex A—Agreement and Plan of Merger

Annex B—Opinion of Centerview Partners, LLC

Annex C—Opinion of Lazard Frères & Co. LLC

Annex D—Section 262 of the Delaware General Corporation Law

iii

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QUESTIONS AND ANSWERS ABOUT THE SPECIAL MEETING AND THE MERGER

The following questions and answers are intended to briefly address some commonly asked questions regarding the special meeting of stockholders and the Merger. These questions and answers do not address all questions that may be important to you as an athenahealth stockholder. Please refer to the more detailed information contained elsewhere in this proxy statement, the Annexes to this proxy statement and the documents referred to in this proxy statement.

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The approval of the non-binding compensation advisory proposal requires the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. Although the Board intends to consider the vote resulting from this proposal, the vote is advisory only and, therefore, is not binding on athenahealth or Parent or any of their respective subsidiaries, and, if the Merger Agreement is adopted by athenahealth stockholders and the Merger is completed, the compensation that is based on or otherwise relates to the Merger will be payable to our named executive officers even if this proposal is not approved. Failures to vote and broker non-votes will have no effect on approval of the proposal; however, the abstention from voting will have the same effect as a vote “AGAINST” the proposal.

The approval of the proposal to adjourn the special meeting if necessary or appropriate requires the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. In addition, even if a quorum is not present at the special meeting, the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter may adjourn the meeting to another place, date or time. In each case, failures to vote and broker non-votes will have no effect on approval of the proposal; however, the abstention from voting will have the same effect as a vote “AGAINST” the proposal.

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For a discussion of the factors that the Board considered in determining to recommend the adoption of the Merger Agreement, please see the section entitled “The Merger—Reasons for Recommending the Adoption of the Merger Agreement,” beginning on page 36. In addition, in considering the recommendation of the Board with respect to the Merger Agreement, you should be aware that some of our directors and executive officers have interests that may be different from, or in addition to, the interests of athenahealth stockholders generally. See the section entitled “The Merger—Interests of Directors and Executive Officers in the Merger,” beginning on page 57.

All shares of athenahealth common stock held by stockholders that are present in person, or represented by proxy, and entitled to vote at the special meeting, regardless of how such shares are voted or whether such stockholders have indicated on their proxy that they are abstaining from voting, will be counted in determining the presence of a quorum. In the absence of a quorum, the special meeting may be adjourned.

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If you are submitting your proxy by telephone or through the Internet, your voting instructions must be received by 11:59 p.m. Eastern Time on the day before the special meeting.

Submitting your proxy by mail, by telephone or through the Internet will not prevent you from voting in person at the special meeting. You are encouraged to submit a proxy by mail, by telephone or through the Internet even if you plan to attend the special meeting in person to ensure that your shares of athenahealth common stock are represented at the special meeting.

If you return your signed proxy card, but do not mark the boxes showing how you wish to vote, your shares will be voted “FOR” the proposal to adopt the Merger Agreement, “FOR” the approval of the non-binding compensation advisory proposal and “FOR” the approval of the proposal to adjourn the special meeting if necessary or appropriate.

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If you have instructed a bank, broker, trust or other nominee to vote your shares, you must follow the instructions received from your bank, broker, trust or other nominee to change your vote.

All properly submitted proxies received by us before the special meeting that are not revoked or changed prior to being exercised at the special meeting will be voted at the special meeting in accordance with the instructions indicated on the proxies or, if no instructions were provided, “FOR” each of the proposals.

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Innisfree M&A Incorporated (“Innisfree”)

501 Madison Avenue, 20th floor

New York, New York 10022

Stockholders may call toll free: (877) 717-3925

Banks and Brokers may call collect: (212) 750-5833

If your shares are held for you by a bank, broker, trust or other nominee, you should also call your bank, broker, trust or other nominee for additional information.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain information in this proxy statement constitutes “forward-looking statements.” Forward-looking statements can be identified by the fact that they do not relate strictly to historical or current facts. They often include words such as “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans,” “seeks” or words of similar meaning, or future or conditional verbs, such as “will,” “should,” “could,” “may,” “aims,” “intends,” or “projects.” However, the absence of these words or similar expressions does not mean that a statement is not forward-looking. These statements may relate to risks or uncertainties associated with:

athenahealth can give no assurance that the expectations expressed or implied in the forward-looking statements contained herein will be attained. The forward-looking statements are made as of the date of this proxy statement, and athenahealth undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law. Readers are cautioned not to place undue reliance on these forward-looking statements that speak only as of the date hereof.

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PARTIES TO THE MERGER

athenahealth

athenahealth, Inc. partners with hospital and ambulatory clients to drive clinical and financial results, including by offering network-based medical records, revenue cycle, patient engagement, care coordination, and population health services. athenahealth’s business also includes Epocrates^® and other point-of-care mobile applications. athenahealth’s principal executive offices are located at 311 Arsenal Street, Watertown, Massachusetts 02472, and our telephone number is (617) 402-1000.

athenahealth became a publicly traded company in 2007. Shares of athenahealth common stock are listed on NASDAQ and trade under the symbol “ATHN.”

Our website address is www.athenahealth.com. The information provided on our website is not part of this proxy statement and is not incorporated by reference in this proxy statement by this or any other reference to our website in this proxy statement.

Additional information about athenahealth is contained in our public filings, which are incorporated by reference in this proxy statement. See the section entitled “Where You Can Find More Information,” beginning on page 106, for more information.

Parent

May Holding Corp., a Delaware corporation, is an affiliate of Veritas and Evergreen and an affiliate of Virence. Following consummation of the Merger, Veritas and Evergreen intend to operationally combine athenahealth and Virence. Parent was formed solely for the purpose of engaging in the transactions contemplated by the Merger Agreement and has not carried on any activities on or prior to the date of this proxy statement, except for activities incidental to its formation and activities undertaken in connection with Parent’s acquisition of athenahealth. Parent has not conducted any business operations other than in connection with the transactions contemplated by the Merger Agreement and the related agreements. Parent’s principal executive offices are located at c/o Veritas Capital Fund Management, L.L.C., 9 West 57th Street, 29th Floor, New York, New York 10019, and its telephone number is (212) 415-6700.

Merger Sub

May Holding Corp. formed May Merger Sub Inc., a Delaware corporation and direct wholly-owned subsidiary of Parent, on November 7, 2018, solely for the purpose of engaging in the transactions contemplated by the Merger Agreement. Merger Sub has not carried on any activities on or prior to the date of this proxy statement, except for activities incidental to its formation and activities undertaken in connection with Parent’s acquisition of athenahealth. Upon completion of the Merger, Merger Sub will merge with and into athenahealth, and Merger Sub will cease to exist. Merger Sub’s principal executive offices are located at c/o Veritas Capital Fund Management, L.L.C., 9 West 57th Street, 29th Floor, New York, NY 10019, and its telephone number is (212) 415-6700.

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THE SPECIAL MEETING

We are furnishing this proxy statement as part of the solicitation of proxies by the Board for use at the special meeting and at any properly convened meeting following an adjournment or postponement of the special meeting.

Date, Time and Place of the Special Meeting

The special meeting will be held on February 7, 2019, at 2:00 P.M. Eastern Time, at our headquarters at 311 Arsenal Street, Watertown, Massachusetts 02472.

athenahealth stockholders who wish to attend the special meeting may be asked to present valid photo identification. Please note that if you hold your shares of athenahealth common stock in “street name” (i.e., in the name of a bank, broker, trust or other nominee) you will need to bring a copy of your voting instruction card or brokerage statement reflecting your stock ownership as of the record date and check in at the registration desk at the meeting. Cameras, sound or video recording devices or any similar equipment, or the distribution of any printed materials, will not be permitted at the meeting without the approval of athenahealth.

Purpose of the Special Meeting

At the special meeting, athenahealth’s stockholders of record will be asked to consider and vote on:

Recommendation of the Board

The Board carefully reviewed and considered the terms and conditions of the Merger Agreement, the Merger and the other transactions contemplated by the Merger Agreement. By a unanimous vote, the Board (i) adopted and declared advisable the Merger Agreement and the Merger and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (ii) authorized and approved the execution, delivery and performance of the Merger Agreement and the consummation by athenahealth of the transactions contemplated by the Merger Agreement, including the Merger, (iii) determined that the transactions contemplated by the Merger Agreement, including the Merger, are in the best interests of athenahealth and its stockholders, (iv) directed that a proposal to adopt the Merger Agreement be submitted to a vote at a meeting of athenahealth stockholders and (v) recommended that athenahealth stockholders vote for the adoption of the Merger Agreement. Accordingly, the Board unanimously recommends a vote “FOR” the proposal to adopt the Merger Agreement.

The Board also unanimously recommends a vote “FOR” the non-binding compensation advisory proposal and “FOR” the approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to adopt the Merger Agreement if there are insufficient votes at the time of the special meeting to adopt the Merger Agreement.

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Record Date and Quorum

Each holder of record of shares of athenahealth common stock as of the close of business on December 18, 2018, which is the record date for the special meeting (the “record date”), is entitled to receive notice of, and to vote at, the special meeting. You will be entitled to one vote for each share of athenahealth common stock that you owned on the record date. As of the record date, there were 41,178,033 shares of athenahealth common stock issued and outstanding and entitled to vote at the special meeting. The presence at the special meeting, in person or by proxy, of the holders of 20,589,017 shares of athenahealth common stock (a majority of the shares of athenahealth common stock issued and outstanding and entitled to vote) constitutes a quorum for the special meeting.

If you are an athenahealth stockholder of record and you vote by mail, by telephone or through the Internet or in person at the special meeting, then your shares of athenahealth common stock will be counted as part of the quorum. If you are a “street name” holder of shares of athenahealth common stock and you provide your bank, broker, trust or other nominee with voting instructions, then your shares will be counted in determining the presence of a quorum. If you are a “street name” holder of shares and you do not provide your bank, broker, trust or other nominee with voting instructions, then your shares will not be counted in determining the presence of a quorum.

All shares of athenahealth common stock held by stockholders of record that are present in person or represented by proxy and entitled to vote at the special meeting, regardless of how such shares are voted or whether such stockholders abstain from voting, will be counted in determining the presence of a quorum. In the absence of a quorum, the special meeting may be adjourned.

Vote Required for Approval

Merger Agreement Proposal. The proposal to adopt the Merger Agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of athenahealth common stock entitled to vote on such matter.

Non-Binding Compensation Advisory Proposal. The approval of the non-binding compensation advisory proposal requires, assuming a quorum is present, the affirmative vote of shares representing at least a majority of the votes properly cast for such matter, that is, at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. The vote is advisory only and, therefore, is not binding on athenahealth or Parent or any of their respective subsidiaries, and, if the Merger Agreement is adopted by athenahealth stockholders and the Merger is completed, the compensation that is based on or otherwise relates to the Merger will be payable to our named executive officers even if this proposal is not approved.

Adjournment Proposal. The approval of the proposal to adjourn the special meeting if necessary or appropriate requires the affirmative vote of shares representing at least a majority of the votes properly cast for such matter, that is, at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. Even if a quorum is not present at the special meeting, the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter or the presiding officer may adjourn the meeting to another place, date or time.

Effect of Abstentions and Broker Non-Votes

The proposal to adopt the Merger Agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of athenahealth common stock entitled to vote on such matter. Therefore, the failure to vote or the abstention from voting will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement.

The approval of the non-binding compensation advisory proposal requires the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. Consequently, failures to vote and broker non-votes will have no effect on approval of the proposal. However, the abstention from voting will have the same effect as a vote “AGAINST” the proposal.

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The proposal to adjourn the special meeting if necessary or appropriate requires the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. Consequently, failures to vote and broker non-votes will have no effect on approval of the proposal. However, the abstention from voting will have the same effect as a vote “AGAINST” the proposal. In addition, even if a quorum is not present at the special meeting, the affirmative vote of shares representing a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter may adjourn the meeting to another place, date or time. In that case, failures to vote and broker non-votes will have no effect on approval of the proposal; however, the abstention from voting will have the same effect as a vote “AGAINST” the proposal.

Under applicable stock exchange rules, all of the proposals in this proxy statement are non-routine matters. Accordingly, if your shares are held in “street name,” a bank, broker, trust or other nominee will NOT be able to vote your shares of athenahealth common stock (referred to as a “broker non-vote”), and your shares will not be counted in determining the presence of a quorum unless you have properly instructed your bank, broker, trust or other nominee on how to vote. Because the proposal to adopt the Merger Agreement requires the affirmative vote of a majority of the outstanding shares of athenahealth common stock, the failure to provide your bank, broker, trust or other nominee with voting instructions will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement. Because the approval of each of (1) the non-binding compensation advisory proposal and (2) the proposal to adjourn the special meeting if necessary or appropriate requires the affirmative vote of shares representing a majority of the voting power of the shares present in person or represented by proxy at the special meeting entitled to vote on such matter, and because your bank, broker, trust or other nominee does not have discretionary authority to vote on either proposal, the failure to provide your bank, broker, trust or other nominee with voting instructions will have no effect on approval of that proposal.

How to Vote

Stockholders have a choice of voting by proxy by completing a proxy card and mailing it in the prepaid envelope provided, by calling a toll-free telephone number or through the Internet. Please refer to your proxy card or the information forwarded by your bank, broker, trust or other nominee to see which options are available to you. The telephone and Internet voting facilities for stockholders of record will close at 11:59 p.m. Eastern Time on the day before the special meeting.

If you submit your proxy by mail, by telephone or through the Internet voting procedures, but do not include “FOR,” “AGAINST” or “ABSTAIN” on a proposal to be voted, your shares of athenahealth common stock will be voted in favor of that proposal. If you indicate “ABSTAIN” on a proposal to be voted, it will have the same effect as a vote “AGAINST” that proposal. If you wish to vote by proxy and your shares are held by a bank, broker, trust or other nominee, you must follow the voting instructions provided to you by your bank, broker, trust or other nominee. Unless you give your bank, broker, trust or other nominee instructions on how to vote your shares of athenahealth common stock, your bank, broker, trust or other nominee will not be able to vote your shares on the proposals.

If you wish to vote in person at the special meeting and your shares are held in the name of a bank, broker or other holder of record, you must obtain a legal proxy, executed in your favor, from the bank, broker or other holder of record authorizing you to vote at the special meeting.

If you do not submit a proxy or otherwise vote your shares of athenahealth common stock in any of the ways described above, it will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement, but will have no effect on the approval of the non-binding compensation advisory proposal or the approval of the proposal to adjourn the special meeting if necessary or appropriate.

If you have any questions about how to vote or direct a vote in respect of your shares of athenahealth common stock, you may contact our proxy solicitor, Innisfree, toll-free at (877) 717-3925 for stockholders or (212) 750-5833 for bankers and brokers.

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YOU SHOULD NOT SEND IN YOUR SHARE CERTIFICATE(S) WITH YOUR PROXY CARD. A letter of transmittal with instructions for the surrender of certificates representing shares of athenahealth common stock or book-entry shares will be mailed to stockholders if the Merger is completed.

Revocation of Proxies

Any proxy given by an athenahealth stockholder may be revoked at any time before it is voted at the special meeting by doing any of the following:

“Street name” holders of shares of athenahealth common stock should contact their bank, broker, trust or other nominee to obtain instructions as to how to revoke or change their proxies.

Adjournments and Postponements

Although it is not currently expected, the special meeting may be adjourned or postponed one or more times to a later day or time if necessary or appropriate, including to solicit additional proxies in favor of the proposal to adopt the Merger Agreement. Your shares will be voted on any adjournment proposal in accordance with the instructions indicated in your proxy or, if no instructions were provided, “FOR” the proposal.

If a quorum is present at the special meeting, the special meeting may be adjourned if there is an affirmative vote of shares representing at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. In addition, even if a quorum is not present at the special meeting, the affirmative vote of shares representing at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter may adjourn the meeting to another place, date or time. In either case, the adjourned meeting may take place without further notice other than by an announcement made at the special meeting unless the adjournment is for more than thirty (30) days thereafter or, if, after the adjournment, a new record date is fixed for the adjourned meeting, in which case a notice of the adjourned meeting will be given to each stockholder of record entitled to vote at the special meeting. If a quorum is not present at the special meeting, or if a quorum is present at the special meeting but there are insufficient votes at the time of the special meeting to adopt the Merger Agreement, then athenahealth may seek to adjourn the special meeting. In addition, the Board may, after consultation with Parent, postpone the special meeting upon public announcement made prior to the date previously scheduled for the special meeting for the purpose of soliciting additional proxies or as otherwise permitted under the Merger Agreement.

Solicitation of Proxies

athenahealth is soliciting the enclosed proxy card on behalf of the Board, and athenahealth will bear the expenses in connection with the solicitation of proxies. In addition to solicitation by mail, athenahealth and its directors, officers and employees may solicit proxies in person, by telephone or by electronic means. These persons will not be specifically compensated for doing this.

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athenahealth has retained Innisfree to assist in the solicitation process. athenahealth will pay Innisfree a fee of approximately $25,000 plus reimbursement of certain specified out-of-pocket expenses. athenahealth also has agreed to indemnify Innisfree against various liabilities and expenses that relate to or arise out of its solicitation of proxies (subject to certain exceptions).

athenahealth will ask banks, brokers, trusts and other nominees to forward athenahealth’s proxy solicitation materials to the beneficial owners of shares of athenahealth common stock held of record by such banks, brokers, trusts or other nominees. athenahealth will reimburse these banks, brokers, trusts or other nominees for their customary clerical and mailing expenses incurred in forwarding the proxy solicitation materials to the beneficial owners.

Stockholder List

A list of athenahealth stockholders entitled to vote at the special meeting will be available for examination by any athenahealth stockholder at the special meeting. At least ten (10) days prior to the date of the special meeting, this stockholder list will be available for inspection by athenahealth stockholders, subject to compliance with applicable provisions of Delaware law, during ordinary business hours at our corporate offices located at 311 Arsenal Street, Watertown, MA 02472.

Questions and Additional Information

If you have more questions about the Merger or how to submit your proxy, or if you need additional copies of this proxy statement or the enclosed proxy card or voting instructions, please call our proxy solicitor, Innisfree, toll-free at (877) 717-3925 for stockholders or (212) 750-5833 for bankers and brokers.

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PROPOSAL 1: ADOPTION OF THE MERGER AGREEMENT

As discussed elsewhere in this proxy statement, athenahealth stockholders will consider and vote on a proposal to adopt the Merger Agreement. You should carefully read this proxy statement in its entirety for more detailed information concerning the Merger Agreement and the Merger. In particular, you should read in its entirety the Merger Agreement, which is attached as Annex A to this proxy statement. In addition, see the sections entitled “The Merger,” beginning on page 28, and “The Agreement and Plan of Merger,” beginning on page 70.

The Board unanimously recommends that athenahealth stockholders vote “FOR” the proposal to adopt the Merger Agreement.

If you return a properly executed proxy card, but do not indicate instructions on your proxy card, your shares of athenahealth common stock represented by such proxy card will be voted “FOR” the proposal to adopt the Merger Agreement.

The approval of the proposal to adopt the Merger Agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of athenahealth common stock entitled to vote on such proposal.

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PROPOSAL 2: NON-BINDING COMPENSATION ADVISORY PROPOSAL

Under Section 14A of the Exchange Act, which was enacted as part of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, we are required to provide our stockholders the opportunity to vote to approve, on a non-binding, advisory basis, the compensation that may be paid or become payable to athenahealth’s named executive officers that is based on or otherwise relates to the Merger, as disclosed in the section entitled “The Merger—Interests of Directors and Executive Officers in the Merger—Golden Parachute Compensation,” beginning on page 62, including the table entitled “Golden Parachute Payment” and accompanying footnotes. Accordingly, athenahealth stockholders are being provided with the opportunity to cast an advisory vote on such payments.

As an advisory vote, this proposal is not binding upon athenahealth or the Board, and approval of this proposal is not a condition to completion of the Merger. Because the Merger-related executive compensation to be paid in connection with the Merger is based on the terms of the Merger Agreement as well as the contractual arrangements between athenahealth and the named executive officers, such compensation will be payable, regardless of the outcome of this advisory vote, if the Merger Agreement is adopted (subject only to the contractual conditions applicable thereto). However, athenahealth seeks your support and believes that your support is appropriate because athenahealth has a comprehensive executive compensation program designed to link the compensation of its executives with athenahealth’s performance and the interests of athenahealth’s stockholders. Accordingly, you are asked to vote on the following resolution:

“RESOLVED, that the stockholders of athenahealth, Inc. approve, on an advisory, non-binding basis, the compensation that may be paid or become payable to the named executive officers of athenahealth, Inc. that is based on or otherwise relates to the Merger, as disclosed pursuant to Item 402(t) of Regulation S-K under the heading “The Merger—Interests of Directors and Executive Officers in the Merger—Golden Parachute Compensation,” beginning on page 62 (which disclosure includes the Golden Parachute Compensation Table required pursuant to Item 402(t) of Regulation S-K).”

The Board unanimously recommends that athenahealth stockholders vote “FOR” the non-binding compensation advisory proposal.

If you return a properly executed proxy card, but do not indicate instructions on your proxy card, your shares of athenahealth common stock represented by such proxy card will be voted “FOR” the non-binding compensation advisory proposal.

The approval of the non-binding compensation advisory proposal requires the affirmative vote of shares representing at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. The vote is advisory only and, therefore, not binding on athenahealth or Parent or any of their respective subsidiaries, and, if the Merger Agreement is adopted by athenahealth’s stockholders and the Merger is completed, the compensation that is based on or otherwise relates to the Merger will be payable to our named executive officers even if this proposal is not approved.

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PROPOSAL 3: AUTHORITY TO ADJOURN THE SPECIAL MEETING

athenahealth stockholders may be asked to adjourn the special meeting to a later date or time if necessary or appropriate, including to solicit additional proxies in favor of the proposal to adopt the Merger Agreement if there are insufficient votes at the time of the special meeting to adopt the Merger Agreement.

The Board unanimously recommends that stockholders vote “FOR” the proposal to adjourn the special meeting to a later date or time if necessary or appropriate, including to solicit additional proxies in favor of the proposal to adopt the Merger Agreement if there are insufficient votes at the time of the special meeting to adopt the Merger Agreement.

If you return a properly executed proxy card, but do not indicate instructions on your proxy card, your shares of athenahealth common stock represented by such proxy card will be voted “FOR” the proposal to adjourn the special meeting to a later date or time if necessary or appropriate.

The approval of the proposal to adjourn the special meeting if necessary or appropriate requires the affirmative vote of shares representing at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter. In addition, even if a quorum is not present at the special meeting, the affirmative vote of shares representing at least a majority of the shares of athenahealth common stock present in person or represented by proxy at the special meeting entitled to vote on such matter may adjourn the meeting to another place, date or time.

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THE MERGER

Overview

athenahealth is seeking the adoption by athenahealth stockholders of the Merger Agreement athenahealth entered into on November 11, 2018 with Parent and Merger Sub. Under the terms of the Merger Agreement, subject to the satisfaction or waiver of specified conditions, Merger Sub will merge with and into athenahealth. athenahealth will survive the Merger as a wholly-owned subsidiary of Parent. The Board has approved the Merger Agreement and unanimously recommends that athenahealth stockholders vote “FOR” the proposal to adopt the Merger Agreement.

Upon completion of the Merger, each share of athenahealth common stock that is issued and outstanding immediately prior to the Effective Time (other than Excluded Shares) will be cancelled, extinguished and automatically converted into the right to receive $135.00 per share, in cash, net of any applicable withholding taxes and without interest.

Following the completion of the Merger, athenahealth will cease to be a publicly traded company and will become a wholly-owned subsidiary of Parent.

Background of the Merger

The Board, together with senior management, regularly reviews and assesses athenahealth’s strategic direction, financial performance and business plans with a view towards strengthening the Company’s business and identifying opportunities to increase stockholder value, taking into account financial, industry, competitive and other considerations. As part of this process, from time to time, the Board and senior management have reviewed potential strategic alternatives, including strategic acquisitions and divestitures, in order to complement and expand the Company’s existing business and operations.

On May 18, 2017, Elliott Associates, L.P. and certain affiliated investment funds, which we refer to collectively as “Elliott,” filed a statement on Schedule 13D announcing that it had acquired beneficial ownership of less than one percent of athenahealth’s outstanding shares of common stock, as well as cash-settled swaps representing economic exposure comparable to an aggregate of 9.3% of athenahealth’s outstanding shares of common stock. Elliott’s Schedule 13D stated that it believed that the Company’s securities represented an attractive investment opportunity.

Over the course of May 2017 to July 2017, representatives of management of athenahealth and the Board held discussions with representatives of Elliott regarding the Company’s financial position and performance, and certain opportunities and strategic initiatives that Elliott believed the Company could pursue. During this period, representatives of Weil, Gotshal & Manges LLP (“Weil”), counsel to athenahealth, also held discussions with representatives of Olshan Frome Wolosky LLP (“Olshan”), counsel to Elliott, with respect to a confidentiality agreement between Elliott and athenahealth which was signed on July 14, 2017.

On August 1, 2017, the Company issued a press release (the “August 1 Release”) announcing that the Board and athenahealth’s management team were conducting a strategic review of the Company’s operational and financial strategy, leadership and governance, including establishing a separate role of president and recruiting an independent chairman of the Board. The August 1 Release further noted that the Company planned to implement a series of initiatives that would generate cost savings and reinvest in its highest-value growth areas.

During September 2017 and October 2017, the Company and Elliott engaged in discussions regarding athenahealth’s performance and certain opportunities and strategic initiatives that Elliott believed the Company could pursue. Also during this period, representatives of Weil and Olshan engaged in discussions with respect to a further confidentiality agreement between Elliott and the Company which was signed on October 13, 2017.

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On November 22, 2017, Elliott sent a private letter to the Board (the “November 22 Letter”), setting out its view that the Company could better pursue and ultimately fulfill its strategy by becoming a private enterprise, and further noting that Elliott would be interested in acquiring athenahealth for between $150 and $155 per share in cash. The November 22 Letter further noted that Elliott believed that with additional diligence, it may also be able to substantially improve its price. On November 24, 2017, representatives of athenahealth’s management contacted representatives of Lazard to discuss their engagement as a financial advisor to the Company in connection with Elliott’s acquiring a stake in athenahealth’s common stock and the November 22 Letter. On December 5, 2017, the Board held a meeting, attended by members of senior management and representatives of Lazard and Weil, to review and discuss the November 22 Letter and the non-binding indication of interest contained therein. Representatives of Weil reviewed with the directors their fiduciary duties. Representatives of Lazard reviewed with the Board certain materials regarding the Company’s financial position and operations, as well as Elliott and other activist shareholders operating in the market generally, which had been prepared by Lazard with the assistance of members of athenahealth’s management. Following discussion, the Board determined that, based on the Company’s prospects and financial performance, the Company’s stock price and the Board’s discussions, it was in the best interests of the Company and its stockholders not to pursue Elliott’s non-binding expression of interest in acquiring the Company. On December 13, 2017, the Company sent Elliott a letter responding to the November 22 Letter, noting that the Board had determined that the Company would continue to operate as a stand-alone company and execute on its strategic plan.

On January 22, 2018, Elliott sent another private letter to the Board (the “January 22 Letter”), stating its view that engaging in a sale transaction would be in the best interests of the Company and its stockholders, and further noting that Elliott continued to be interested in acquiring athenahealth for between $150 and $155 per share in cash subject to due diligence.

On February 2, 2018, the Board held a telephonic meeting attended by members of senior management and Weil, at which the Board reviewed, among other things, the January 22 Letter. Following discussion, the Board determined that, based on the Company’s prospects and financial performance, the Company’s stock price and the Board’s discussions, it was in the best interests of the Company and its stockholders not to pursue Elliott’s non-binding expression of interest in acquiring the Company outlined in the January 22 Letter.

On February 7, 2018, the Company appointed Jeffrey Immelt as Chairman of the Board.

On May 7, 2018, Elliott sent and simultaneously publicly released a letter to the Board (the “May 7 Letter”) outlining a non-binding proposal to acquire the Company for $160 per share in cash.

On May 7, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Lazard and Weil, at which it reviewed, among other things, the May 7 Letter and the non-binding indication of interest contained therein. Representatives of Weil reviewed with the directors their fiduciary duties. Following discussion, the Board determined that the Company should conduct further analyses, with the assistance of its advisers, to assist the Board in reviewing and determining a course of action in connection with Elliott’s non-binding expression of interest in acquiring the Company outlined in the May 7 Letter. Also on May 7, 2018, athenahealth issued a press release confirming that it had received an unsolicited proposal from Elliott to acquire the Company for $160 per share in cash, and noting that consistent with its fiduciary duties and following consultation with its independent financial and legal advisors, the Board would carefully review the proposal to determine the course of action that it believed was in the best interest of the Company and its stockholders. Also on May 7, 2018, Elliott amended its statement on Schedule 13D to disclose the May 7 Letter.

On May 14, 2018, Elliott sent, and publicly released, a letter to the Board (the “May 14 Letter”) reiterating its non-binding proposal to acquire the Company for $160 per share in cash. Also on May 14, 2018, Jonathan Bush, then President and Chief Executive Officer of athenahealth, sent a letter to Elliott confirming that the Company had received the May 7 Letter and that, as disclosed in the press release issued by the Company on May 7, 2018, the Board was reviewing the non-binding proposal contained therein and would respond in due course.

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On May 15, 2018, representatives of athenahealth’s management contacted representatives of Centerview to discuss their engagement as an additional financial advisor to the Company, alongside Lazard, in connection with review of Elliott’s non-binding indication of interest and related matters.

On May 16, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, it reviewed the May 14 Letter and the non-binding indication of interest contained therein, and received an update from the Company’s management and its advisors on the news articles and communications that had been received from athenahealth’s stockholders in connection with Elliott’s public announcement of its non-binding indication of interest in acquiring the Company, and the effect that Elliott’s public announcements had had on athenahealth’s stock price and stockholder profile. Following the discussion, the Board determined that management should update the existing financial analyses and the five-year management projections for the Company’s forecasted performance to assist the Board in evaluating the Company’s standalone plan and in reviewing and determining a course of action in connection with Elliott’s non-binding expression of interest in acquiring the Company outlined in the May 14 Letter. It was agreed that the Board and its advisors would reconvene on May 22, 2018 for further discussion.

On May 22, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, management of the Company presented to the Board the updated five-year management projections for the Company’s forecasted performance (the “May 2018 Model”). The Board discussed with management and its advisors the process by which the projections had been prepared, the key assumptions underlying the May 2018 Model, and various positive and negative metrics that were presented in the model. The Board, along with management and the Company’s advisors, considered various sensitivities or alternative assumptions that would impact certain areas of measurement and the overall financial forecast for the Company. Following the discussion, the Board instructed Centerview and Lazard to prepare preliminary financial analyses of Elliott’s non-binding indication of interest to acquire the Company for $160 per share and of the Company’s standalone value, for presentation to the Board at a meeting to be scheduled for May 31, 2018.

On May 24, 2018, Elliott sent, and publicly released, a letter to the Board (the “May 24 Letter”) reiterating its proposal to acquire the Company for $160 per share in cash and providing that Elliott was eager to engage in customary due diligence. Also on May 24, 2018, the Company issued a press release (the “May 24 Release”) in response to the May 24 Letter, noting that the Board was undertaking a thorough and deliberate analysis of Elliott’s proposal to acquire the Company for $160 per share in cash, and that it would continue to take the time necessary to complete its review. The May 24 Release also noted that the Board would communicate the results of its analysis and its recommendation promptly after taking the time necessary to complete its work, so that it would be able to recommend actions that it determines are in the best interests of all stockholders.

On May 31, 2018, a representative of Elliott, emailed a representative of management of athenahealth, requesting a call between a representative of Elliott and Mr. Immelt. The representative of athenahealth’s management responded on the same date, confirming that the Company would be able to arrange a call between a representative of Elliott and Mr. Immelt, with other athenahealth directors and members of athenahealth management also present, similar to the access to the Board that had been made available to other stockholders of the Company.

On May 31, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, representatives of Centerview and Lazard reviewed with the Board their preliminary financial analyses. The Board discussed various strategic alternatives that may be available to athenahealth, including continuing as a standalone public company while implementing alternatives reflected by the May 2018 Model, a sale of athenahealth to Elliott on the terms reflected in the May 14 Letter, and a sale of the Company to any other buyer by initiating a formal sale process. Representatives of Weil reviewed with the directors their fiduciary duties. Following discussion, the Board

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determined that it would review and discuss in further detail at its next meeting the May 2018 Model and the preliminary financial analyses presented by Centerview and Lazard, as well as the various strategic alternatives that may be available to athenahealth.

On June 5, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Weil at which, among other things, it reviewed the discussions that the Board had over the prior few weeks, including discussions with respect to the May 2018 Model, the preliminary financial analyses prepared by Centerview and Lazard, and the media reports concerning the Company and Mr. Bush that had been published in recent weeks. Representatives of Weil reviewed with the directors their fiduciary duties. Following discussion, the Board determined that, based on the Company’s prospects and financial performance, the Company’s stock price, the analyses presented by management and the advisers and the Board’s discussions, it was in the best interests of the Company and its stockholders to initiate a formal process to explore strategic alternatives for the Company. On June 6, 2018, the Company issued a press release (the “June 6 Release”) announcing that the Board had determined to initiate a formal process to explore strategic alternatives, including as part of this process that the Board would consider a sale, merger or other transaction involving the Company as well as continuing as an independent company. The June 6 Release also announced that Mr. Bush had stepped down as President, Chief Executive Officer and as a member of the athenahealth Board, effective immediately, and that in parallel to its consideration of strategic alternatives, athenahealth would initiate a search process to identify qualified CEO candidates. The June 6 Release further announced that Mr. Immelt had been appointed as Executive Chairman.

Following the Board’s determination to initiate a formal process to explore strategic alternatives for the Company, representatives of Centerview and Lazard commenced a broad outreach, contacting sixty-five (65) parties, comprised of thirty-two (32) companies and thirty-three (33) financial sponsors, including Veritas. Between June 13, 2018 and July 20, 2018, representatives of Weil negotiated the terms of, and arranged for the Company to sign, confidentiality agreements with a total of thirty-one (31) of the sixty-five (65) parties contacted by Centerview and Lazard, comprising of six (6) companies and twenty-five (25) financial sponsors, including, separately, Elliott and Veritas. Each party that signed a confidentiality agreement was provided access to certain non-public materials regarding the Company’s business and operations, and an opportunity to arrange a call with members of the Company’s management team. Between June 25, 2018 and July 10, 2018, members of the Company’s management team held a total of twenty-seven (27) due diligence teleconferences with twenty-five (25) potential buyers, including, separately, with Elliott and Veritas. In addition, one (1) party declined to enter into confidentiality agreements but held discussions with management and representatives of Centerview and Lazard based on publicly available information.

During the period outlined above, representatives of each of Elliott and Veritas separately engaged with representatives of the Company and its advisors as part of the potential sale process, including in connection with the negotiation and execution by each of Veritas and Elliott of separate confidentiality agreements with the Company.

On June 27, 2018, the Board held a telephonic meeting attended by members of senior management at which among other things, it received an update on the process to explore strategic alternatives, including a sale of the Company. During the meeting, senior management provided an overview of the expected timing of the strategic alternatives process and an initial list of potentially interested parties.

Between June 25, 2018 and July 3, 2018, representatives of Centerview and Lazard delivered a first round process letter to twenty-nine (29) parties, including Elliott and Veritas, outlining, among other things, that interested parties should each submit a non-binding written proposal no later than July 11, 2018, and the details to be included with respect to such proposals.

On July 6, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, it received an update on the

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process to explore strategic alternatives, including the potential strategic and financial buyers who had been contacted to date by Centerview and Lazard, the status of management presentations and the level of interest among potential buyers who had attended diligence sessions with management.

On July 11, 2018 and July 12, 2018, ten (10) parties, including each of Elliott and Veritas on behalf of Virence (separately), presented athenahealth with written preliminary non-binding indications of interest, with prices ranging in the $145 to $165 per share range. Additionally, one party requested an extension of time to submit a written proposal and on July 16, 2018, athenahealth received one inbound expression of interest. One further written preliminary non-binding indication of interest was submitted on August 7, 2018 at $160 per share.

On July 16, 2018, the Board held a telephonic meeting (the “July 16 Meeting”) attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, it received an update on the process to explore strategic alternatives, including a summary of the written offers that had been received from potential buyers. Following discussion, the Board determined to continue to evaluate each of these offers by continuing to engage with the interested potential buyers who had submitted written offers and authorized its advisors to proceed as such. The Board also authorized the retention of Centerview and Lazard as financial advisors to the Board in connection with athenahealth’s review of strategic alternatives, including a potential sale transaction. Following the Board’s authorization of their engagement, engagement letters were negotiated with each of Centerview and Lazard and, in October 2018, the Company entered into such engagement letters with Centerview and Lazard.

Following the July 16 Meeting, eleven (11) parties were provided access to a virtual data room in connection with the sale process. The virtual data room contained certain non-public information and materials, and additional non-public information and materials continued to be made available in the data room between July 2018 and November 2018 in connection with the sale process, including in response to requests for further information and diligence requests made by potential buyers.

On July 25, 2018, the Board held a meeting (the “July 25 Meeting”) attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, the Board received an update on the process to explore strategic alternatives, including regarding the potential strategic and financial buyers that were involved in the process, the status and key themes coming out of management presentations and due diligence sessions, and the Company’s advisors’ perspectives on the apparent relative levels of interest among potential buyers who remained involved in the process. Representatives of Centerview and Lazard also presented to the Board an overview of the level of interest of each party advancing in the process, including their preliminary views and understandings of the potential investment theses of each such party where possible. At the July 25 Meeting, the Board and its advisors also discussed the type and amount of additional diligence that the advancing parties were expected to require in order to submit a binding proposal to acquire the Company.

During the period of July 26, 2018 to August 13, 2018, the Company’s management and representatives of Centerview and Lazard conducted nine (9) in-person due diligence sessions with eleven (11) parties, including certain parties that were partnering in their review, in Boston, Massachusetts. During this period, additional non-public information and materials continued to be made available in the data room.

On August 20, 2018, representatives of Centerview and Lazard delivered a second round process letter to nine (9) parties, including each of Elliott and Veritas on behalf of Virence (separately), outlining, among other things, that interested parties should each submit final written proposal no later than September 17, 2018, and the details to be included with such proposals. The date for submission of final bids was subsequently revised to September 26, 2018. Also on August 20, 2018, representatives of Weil made available in the data room a draft merger agreement in connection with the proposed transaction.

On August 29, 2018, the Board held a telephonic meeting attended by members of senior management at which, among other things, it received an update on the process to explore strategic alternatives, including an

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overview of the interested parties, the timing and focus of the due diligence review and expectation for next steps in the strategic alternatives process.

On September 24, 2018, the Board held a meeting (the “September 24 Meeting”) attended telephonically by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, it received an update on the process to explore strategic alternatives, including regarding the potential strategic and financial buyers who remained involved in the process, the status and key themes coming out of management presentations and diligence sessions to date, the potential buyers who were expected to submit final offers during that week and the process and schedule going forward.

From September 26, 2018 to September 28, 2018, four (4) parties, including Veritas (on behalf of Virence), presented athenahealth with written offers to acquire the Company, with prices ranging between $120 and $135 per share. Additionally, one consortium (the “Consortium”) comprised of three (3) parties submitted a proposal to the Company for a strategic partnership with the Company, and Elliott presented athenahealth with a proposal for it to partner with another party to acquire the Company at a purchase price equal to approximately $145 per share.

On September 30, 2018, the Board held a telephonic meeting (the “September 30 Meeting”) attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, the Board received an update on the process to explore strategic alternatives, including a summary of the written offers that had been submitted to the Company that week by potential buyers. Representatives of Centerview and Lazard also reviewed with the Board their preliminary financial analyses of the offers and the Company as a standalone business. The Board discussed the strategic alternatives available to athenahealth, including continuing as a standalone public company while implementing alternatives reflected by the May 2018 Model, a sale of athenahealth to a strategic or financial buyer on the terms reflected in the final offers received, and a partnership between athenahealth and the Consortium on the terms reflected in the offer received from the Consortium. Following discussion, the Board instructed management and its advisors to continue to engage with four (4) parties (two of whom were partnered together) and to communicate a deadline of October 19, 2018 for such parties to submit their final proposals. The Board determined the parties to move forward with based on the specifics of their proposals, including the value such bids could provide to the Company’s shareholders, as well as the strength of the bidding parties’ ability to complete a transaction. Additionally, the Board instructed management to conduct further analysis on the Consortium’s proposal along the same timeline.

Between October 1, 2018 and October 29, 2018, members of the Company’s management, together with representatives of Centerview, Lazard and Weil, continued to provide certain non-public information and materials to representatives of those parties authorized by the Board to continue to progress in the Company’s sale process.

On October 10, 2018, athenahealth’s management prepared and presented to representatives of Centerview and Lazard an updated draft five-year management forecast, which reflected management’s revised forecast in light of the Company’s business performance to date and certain information that had been learned through the diligence process with potential buyers, as well as what the Company might be able to achieve if it pursued a standalone strategy.

On October 12, 2018, the Board held a telephonic meeting (the “October 12 Meeting”) attended by members of senior management and Weil, at which, among other things, the Board received an update on developments related to the business since the May 2018 Model. Members of the Company’s management then reviewed with the Board the forecasts that were provided to Centerview and Lazard on October 10, 2018. The Board discussed with management the process by which such forecasts had been prepared, including the key assumptions underlying such forecasts, and various positive and negative metrics that were presented in such forecasts as compared to the May 2018 Model. Following discussion, the Board directed athenahealth to continue to refine such forecasts, and then to authorize Centerview and Lazard to provide such forecasts as revised to bidders. Also at the October 12 Meeting, representatives of McKinsey & Company (“McKinsey”), consultant advisors to the Company, presented to the Board the results of the analyses that had been conducted by McKinsey with the assistance of athenahealth’s management in assessing the Consortium’s proposal for a strategic partnership with the Company.

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On October 16, 2018, athenahealth provided to bidders the “October 2018 Model” described under the section captioned “—Certain Financial Projections” below.

On October 22, 2018, two (2) bidders (being “Party B” and another party, “Party C”) submitted offers to acquire the Company for between $117 and $125 per share in cash. On October 24, 2018, Veritas (on behalf of Virence) submitted a revised proposal to acquire the Company for $127.50 to $132.50 per share in cash, to be financed through a combination of equity and debt, including equity financing to come from both Veritas and Elliott.

On October 24, 2018, the Board held a meeting (the “October 24 Meeting”) attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, the Board received an update on developments related to the business since the October 12 Meeting. Members of the Company’s management then presented to the Board the October 2018 Model. The Board discussed with management and its advisors the process by which the October 2018 Model had been prepared, including the key assumptions underlying the October 2018 Model, and various positive and negative metrics that were presented in the October 2018 Model compared to the May 2018 Model. Following discussion, the Board discussed the need for refining the management forecasts and potentially reflecting various sensitivities or alternative assumptions, for the purpose of further informing the Board’s view of the Company’s intrinsic value and the Company’s prospects on a standalone basis. The Board determined that the Company’s management should carefully evaluate the assumptions and sensitivities underlying the forecasts, and assess the risk associated with, various elements of the October 2018 Model, in order to further refine a financial model (the “Adjusted Management Model”) that should be referred to by the Board in its review of the Company’s standalone plan, and by Centerview and Lazard for the purpose of preparing their financial analyses. The Board was focused on evaluating the proposals against the standalone scenario and understanding the risks and uncertainties of continuing to execute on the strategic plan. At the meeting, the Board received an update on the process to explore strategic alternatives, including a summary of the bids that had been received from three (3) parties to acquire the Company. Representatives of Centerview and Lazard presented their preliminary financial analyses. The Board discussed the strategic alternatives available to athenahealth, including continuing as a standalone public company while implementing alternatives reflected by the October 2018 Model and a sale of athenahealth to a strategic or financial buyer on the terms reflected in the offers received. Following discussion, the Board determined that, based on the Company’s prospects, the analyses presented by management and the advisers and the Board’s discussions, it would only pursue a sale of the Company if the price per share was at a minimum $130. The Board also determined to delay filing of its earnings release to November 9, 2018 and its earnings call to November 12, 2018.

During the period of October 25, 2018 to October 29, 2018, representatives of Centerview, Lazard and Weil continued to provide certain non-public information and materials to, and to respond to due diligence requests from, representatives of Veritas (on behalf of Virence), Elliott and Party C.

On October 29, 2018, Schulte Roth & Zabel LLP (“Schulte”), counsel to Veritas and Virence, provided Weil with their initial comments to Weil’s draft of the merger agreement. On October 30, 2018, the Company and Veritas (on behalf of Virence) executed an exclusivity agreement providing that, among other things, the Company would negotiate a direct or indirect sale transaction exclusively with Veritas (on behalf of Virence) at a per share price equal to no less than $135 per share until November 12, 2018, provided that Veritas confirmed on every second day following execution of the exclusivity agreement that the terms and conditions of its final binding offer would not differ, in any material respect, from the terms proposed by Veritas on October 29, 2018, and that Veritas (on behalf of Virence) remains committed in good faith to announce a transaction on the timeframe agreed between the parties.

On October 30, 2018, the Board held a telephonic meeting attended by members of senior management and representatives of Weil, at which, among other things, the Board received an update on the process to explore strategic alternatives. During this meeting, the Board reaffirmed its position that, based on the Company’s prospects, the analyses presented by management and the advisers and the Board’s discussions, it would only pursue a sale of the Company if the per share price was at a minimum $130.

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During the period of October 30, 2018 to November 11, 2018, the Company and its representatives continued to provide additional due diligence information to Veritas (on behalf of Virence) and its representatives, including telephonic due diligence conferences. During this period, Veritas (on behalf of Virence) confirmed on each second calendar day that the terms and conditions of its final binding offer would not differ, in any material respect, from the terms proposed by Veritas on October 29, 2018, and that Veritas (on behalf of Virence) remained committed in good faith to announce a transaction on the timeframe agreed between the parties.

During the time period between November 3, 2018 and November 11, 2018, representatives of Weil and Schulte exchanged drafts and held a series of phone calls to negotiate and finalize the terms of the merger agreement, the Company’s disclosure letter relating to the merger agreement, the equity commitment letters for Virence and Elliott and the limited guarantees for Veritas and Elliott.

On November 11, 2018, the Board held a telephonic meeting (the “November 11 Meeting”) attended by members of senior management and representatives of Centerview, Lazard and Weil, at which, among other things, the Board received an update on the process to explore strategic alternatives. At the November 11 Meeting, representatives of Centerview reviewed with the Board Centerview’s financial analysis of the Merger Consideration, and rendered to the Board an oral opinion, which was subsequently confirmed by delivery of a written opinion dated such date that, as of such date and based upon and subject to various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken in preparing its opinion, the Merger Consideration to be paid to the holders of shares of Company Common Stock (other than as specified in such opinion) pursuant to the Merger Agreement was fair, from a financial point of view, to such holders. For a detailed discussion of Centerview’s opinion, please see below under the caption “–Opinion of athenahealth’s Financial Advisors – Opinion of Centerview Partners LLC”. Also at the November 11 Meeting, representatives of Lazard reviewed with the Board Lazard’s financial analysis of the Merger Consideration, and rendered to the Board an oral opinion, which was subsequently confirmed by delivery of a written opinion dated such date that, as of such date and based upon and subject to various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken in preparing its opinion, the Merger Consideration to be paid to the holders of shares of Company Common Stock (other than as specified in such opinion) pursuant to the Merger Agreement was fair, from a financial point of view, to such holders. For a detailed discussion of Lazard’s opinion, please see below under the caption “–Opinion of athenahealth’s Financial Advisors – Opinion of Lazard Frères & Co. LLC”. Further, at the November 11 Meeting, representatives of Weil reviewed with the directors their fiduciary duties and a summary of the key terms of a substantially final draft of the merger agreement that had been negotiated with Veritas (on behalf of Virence) in connection with the proposed transaction. After further discussing potential reasons for and against the proposed transaction (see below under the heading “—Recommendation of the Board of Directors and Reasons for the Merger—Reasons for the Merger”), the Board unanimously adopted and declared advisable the Merger Agreement, declared that the Merger Agreement was in the best interests of athenahealth and its stockholders, and recommended that athenahealth’s stockholders approve the Merger Agreement. The Board directed representatives of Weil to continue to finalize the terms of the Merger Agreement in accordance with the summary of terms reviewed with the Board.

Following the November 11 Meeting, the parties finalized and executed the Merger Agreement and the disclosure letter and received executed final copies of the limited guarantee, the equity commitment letters, the debt commitment letter and the preferred equity commitment letter.

On the morning of November 12, 2018, prior to the opening of trading of athenahealth common stock on the NASDAQ, athenahealth, Veritas and Elliott issued a joint press release announcing the execution of the Merger Agreement.

Recommendation of the Board

At a meeting of the Board on November 11, 2018, after careful consideration, including detailed discussions with athenahealth’s management and its legal and financial advisors, the Board unanimously:

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Reasons for Recommending the Adoption of the Merger Agreement

At a meeting held on November 11, 2018, the Board unanimously approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger. The Board recommends the athenahealth stockholders approve and adopt the Merger Agreement and the Merger.

In arriving at this determination and recommendation, the Board reviewed and discussed a significant amount of information and consulted with athenahealth’s management, legal advisors and financial advisors. The following are some of the significant factors that supported its decision to approve the Merger Agreement (not necessarily in order of relative importance):

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In the course of its deliberations, the Board also considered certain risks and other potentially negative factors concerning the transactions contemplated by the Merger Agreement, including:

The foregoing discussion of the information and factors considered by the Board is not intended to be exhaustive, but includes the material factors considered by the Board. In view of the wide variety of factors considered in connection with its evaluation of the Merger and the complexity of these matters, the Board did not find it practicable to, and did not, quantify or otherwise assign relative weights to the specific factors considered in reaching its determination and recommendation. In addition, individual directors may have given different weights to different factors. The Board did not undertake to make any specific determination as to whether, or to what extent, any factor, or any particular aspect of any factor, supported or did not support its ultimate

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determination. The Board based its recommendation on the totality of the information presented, including the factors described above.

Certain Financial Projections Utilized in Connection with the Merger

In the course of due diligence, athenahealth provided Parent with non-public financial information relating to athenahealth, including certain internal financial forecasts, estimates and other financial and operating data relating to athenahealth prepared by the management of athenahealth for fiscal years 2018 through 2023, which forecasts are referred to herein as the October 2018 Model. As described above in the section titled “The Merger—Background of the Merger”, the Board instructed athenahealth’s management to refine the October 2018 Model to reflect various sensitivities or alternative assumptions, for the purpose of further informing the Board’s view of the Company’s intrinsic value and the Company’s prospects on a standalone basis, and such model is referred to herein as the Adjusted Management Model. The Adjusted Management Model was made available to the Board for use in its evaluation of the Merger and also was provided to Centerview and Lazard which were directed to use and rely upon the Adjusted Management Model for purposes of their financial analyses and respective opinions.

The Adjusted Management Model is based on numerous variables and assumptions made by athenahealth management at the time prepared, including with respect to industry performance, general business, economic, regulatory, market and financial conditions and other future events, as well as matters specific to athenahealth.

The following table presents a summary of the October 2018 Model:

(1) Adjusted EBITDA is defined as net income before interest expense, income tax expense (benefit), depreciation and amortization, stock-based compensation expense and other expenses.

(2) Adjusted Operating Income is defined as net income before interest expense, income tax expense (benefit), stock-based compensation expense, amortization of purchased intangible assets, amortization of capitalized stock-based compensation related to software development, and other expenses.

(3) Excludes amortization of purchased intangibles and amortization of capitalized stock-based compensation related to software development.

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The following table presents a summary of the Adjusted Management Model:

(1) Adjusted EBITDA is defined as net income before interest expense, income tax expense (benefit), depreciation and amortization, stock-based compensation expense and other expenses.

(2) Adjusted Operating Income is defined as net income before interest expense, income tax expense (benefit), stock-based compensation expense, amortization of purchased intangible assets, amortization of capitalized stock-based compensation related to software development, and other expenses.

(3) Excludes amortization of purchased intangibles and amortization of capitalized stock-based compensation related to software development.

(4) For purposes of each of Centerview’s and Lazard’s separate analyses, Unlevered Free Cash Flow defined (and calculated by each of Centerview and Lazard using the Adjusted Management Model) as Adjusted EBITDA (i) less Stock-Based Compensation, Depreciation and Amortization, (ii) less taxes (applying a 20.0% cash tax rate for 2018 and a 24.7% cash tax rate thereafter, as provided by the Company) to the amount calculated thus far, (iii) plus Depreciation and Amortization, (iv) less Capital Expenditures and Capitalized Software Costs, and (v) less the Cash Impact of Net Working Capital and Other, in each case as approved for Centerview’s and Lazard’s use by the Company. The Unlevered Free Cash Flow for 2018 reflects the 3-month period from October to December of 2018 (all other figures presented reflect full-year values).

(5) In performing their respective discounted cash flow analyses of the Company, Centerview and Lazard each used the Unlevered Free Cash Flows of the Company over the period beginning October 1, 2018 and ending on December 31, 2022. In addition, Centerview and Lazard each used the Adjusted EBITDA of the Company in 2023 in connection with their respective calculations of the implied terminal values of the Company. For further information regarding Centerview’s and Lazard’s respective discounted cash flow analyses of the Company, see “–Opinion of Centerview Partners LLC” and “–Opinion of Lazard Frères & Co. LLC”.

The inclusion of information about the Adjusted Management Model in this proxy statement should not be regarded as an indication that any of athenahealth, Parent or any other recipient of this information considered, or now considers, it necessarily predictive of actual future results or material information given the inherent risks and uncertainties associated with such forecasts.

The Adjusted Management Model is subjective in many respects and, thus, subject to interpretation. Although presented with numeric specificity, the Adjusted Management Model reflects numerous estimates and assumptions with respect to industry performance and competition, general business, economic, market and financial conditions and matters specific to athenahealth’s and Parent’s businesses, including the factors listed under “Risk Factors”, all of which are difficult to predict and many of which are beyond athenahealth’s or Parent’s control. athenahealth cannot provide any assurance that the assumptions underlying the Adjusted Management Model will be realized.

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Many of the assumptions reflected in the Adjusted Management Model are subject to change and the Adjusted Management Model does not reflect revised prospects for athenahealth’s or Parent’s business, changes in general business or economic conditions or any other transaction or event that has occurred or that may occur and that was not anticipated at the time such financial information was prepared. athenahealth has not updated and does not intend to update or otherwise revise the Adjusted Management Model. There can be no assurance that the results reflected in the Adjusted Management Model will be realized or that actual results will not materially vary from the Adjusted Management Model. In addition, the Adjusted Management Model cover multiple years and such information by its nature becomes less predictive with each successive year. Therefore, the Adjusted Management Model included in this proxy statement should not be relied on as necessarily predictive of actual future events nor construed as financial guidance.

athenahealth stockholders are urged to review athenahealth’s most recent SEC filings for a description of risk factors with respect to athenahealth’s business. You should read “Cautionary Statement Regarding Forward-Looking Statements” for additional information regarding the risks inherent in forward-looking information such as the Adjusted Management Model and “Where You Can Find More Information”.

The Adjusted Management Model was not prepared with a view toward complying with U.S. General Accepted Accounting Principles (“GAAP”) (including because certain metrics are non-GAAP measures, and the forecasts contained therein do not include footnote disclosures as may be required by GAAP), the published guidelines of the SEC regarding projections or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. Neither athenahealth’s independent registered public accounting firm, nor any other independent accountants, have compiled, examined, or performed any procedures with respect to the Adjusted Management Model, nor have they expressed any opinion or any other form of assurance on the Adjusted Management Model or the achievability of the results reflected in the Adjusted Management Model, and they assume no responsibility for, and disclaim any association with, the Adjusted Management Model. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in compliance with GAAP, and non-GAAP financial measures such as those used in the Adjusted Management Model may not be comparable to similarly titled amounts used by other companies or persons.

The non-GAAP financial measures set forth above should not be considered a substitute for, or superior to, financial measures determined or calculated in accordance with U.S. GAAP. athenahealth is not providing a quantitative reconciliation of these forward-looking non-GAAP financial measures. In accordance with Item 10(e)(1)(i)(B) of Regulation S-K of the Securities Act of 1933, a quantitative reconciliation of a forward-looking non-GAAP financial measure is only required to the extent it is available without unreasonable efforts. athenahealth does not currently have sufficient data to accurately estimate the variables and individual adjustments for such reconciliation, or to quantify the probable significance of these items at this time. The adjustments required for any such reconciliation of athenahealth’s forward-looking non-GAAP financial measures cannot be accurately forecast by athenahealth, and therefore the reconciliation has been omitted. For the reasons described above, readers of this proxy statement are cautioned not to place undue, if any, reliance on the Adjusted Management Model. athenahealth has not made any representation to Parent in the Merger Agreement concerning any of the Adjusted Management Model.

The information about the Adjusted Management Model set forth above does not give effect to the Merger and also does not take into account the effect of any failure of the Merger to be consummated.

ATHENAHEALTH DOES NOT INTEND TO UPDATE OR OTHERWISE REVISE THE ABOVE ADJUSTED MANAGEMENT MODEL TO REFLECT CIRCUMSTANCES EXISTING AFTER THE DATE WHEN MADE OR TO REFLECT THE OCCURRENCE OF FUTURE EVENTS, EVEN IN THE EVENT THAT ANY OR ALL OF THE ASSUMPTIONS UNDERLYING SUCH FORECASTS ARE NOT REALIZED.

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Opinion of Centerview Partners LLC

On November 11, 2018, Centerview rendered to the Board its oral opinion, subsequently confirmed by delivery of a written opinion dated November 11, 2018, that, as of such date and based upon and subject to various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, the Merger Consideration to be paid to the holders of shares of Company Common Stock (other than Excluded Shares) pursuant to the Merger Agreement was fair, from a financial point of view, to such holders.

The full text of Centerview’s written opinion, dated November 11, 2018, which describes the assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, is attached as Annex B and is incorporated herein by reference. The summary of the written opinion of Centerview set forth below is qualified in its entirety by the full text of Centerview’s written opinion attached as Annex B. Centerview’s financial advisory services and opinion were provided for the information and assistance of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the Transaction and Centerview’s opinion only addressed the fairness, from a financial point of view, as of the date thereof, to the holders of shares of Company Common Stock (other than Excluded Shares) of the Merger Consideration to be paid to such holders pursuant to the Merger Agreement. Centerview’s opinion did not address any other term or aspect of the Merger Agreement or the Transaction and does not constitute a recommendation to any stockholder of the Company or any other person as to whether such stockholder should have executed a consent with respect to the Merger or as to how such stockholder or other person should otherwise act with respect to the Transaction or any other matter.

The full text of Centerview’s written opinion should be read carefully in its entirety for a description of the assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion.

In connection with rendering the opinion described above and performing its related financial analyses, Centerview reviewed, among other things:

Centerview also participated in discussions with members of the senior management and representatives of the Company regarding their assessment of the Internal Data. In addition, Centerview reviewed publicly available financial and stock market data, including valuation multiples, for the Company and compared that data

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with similar data for certain other companies, the securities of which are publicly traded, in lines of business that Centerview deemed relevant. Centerview also compared certain of the proposed financial terms of the Transaction with the financial terms, to the extent publicly available, of certain other transactions that Centerview deemed relevant, and conducted such other financial studies and analyses and took into account such other information as Centerview deemed appropriate.

Centerview assumed, without independent verification or any responsibility therefor, the accuracy and completeness of the financial, legal, regulatory, tax, accounting and other information supplied to, discussed with, or reviewed by Centerview for purposes of its opinion and, with the Company’s consent, Centerview relied upon such information as being complete and accurate. In that regard, Centerview assumed, at the Company’s direction, that the Internal Data (including, without limitation, the Forecasts) were reasonably prepared on bases reflecting the best currently available estimates and judgments of the management of the Company as to the matters covered thereby and Centerview relied at the Company’s direction on the Internal Data for purposes of Centerview’s analysis and opinion. In connection therewith, Centerview was advised by the Company that the Forecasts most recently prepared by management of the Company and presented to the Board best reflect the good faith judgments of the Board as to the Company’s future financial performance and, accordingly, Centerview was instructed by the Board to only use those Forecasts for purposes of Centerview’s analysis and opinion. Centerview expressed no view or opinion as to the Internal Data or the assumptions on which it was based. In addition, at the Company’s direction, Centerview did not make any independent evaluation or appraisal of any of the assets or liabilities (contingent, derivative, off-balance-sheet or otherwise) of the Company, nor was Centerview furnished with any such evaluation or appraisal, and was not asked to conduct, and did not conduct, a physical inspection of the properties or assets of the Company. Centerview assumed, at the Company’s direction, that the final executed Merger Agreement would not differ in any respect material to Centerview’s analysis or opinion from the Draft Merger Agreement reviewed by Centerview. Centerview also assumed, at the Company’s direction, that the Transaction will be consummated on the terms set forth in the Merger Agreement and in accordance with all applicable laws and other relevant documents or requirements, without delay or the waiver, modification or amendment of any term, condition or agreement, the effect of which would be material to Centerview’s analysis or Centerview’s opinion and that, in the course of obtaining the necessary governmental, regulatory and other approvals, consents, releases and waivers for the Transaction, no delay, limitation, restriction, condition or other change will be imposed, the effect of which would be material to Centerview’s analysis or Centerview’s opinion. Centerview did not evaluate and did not express any opinion as to the solvency or fair value of the Company, or the ability of the Company to pay its obligations when they come due, or as to the impact of the Transaction on such matters, under any state, federal or other laws relating to bankruptcy, insolvency or similar matters. Centerview is not a legal, regulatory, tax or accounting advisor, and Centerview expressed no opinion as to any legal, regulatory, tax or accounting matters.

Centerview’s opinion expressed no view as to, and did not address, the Company’s underlying business decision to proceed with or effect the Transaction, or the relative merits of the Transaction as compared to any alternative business strategies or transactions that might be available to the Company or in which the Company might engage. Centerview’s opinion was limited to and addressed only the fairness, from a financial point of view, as of the date of Centerview’s written opinion, to the holders of the shares of Company Common Stock (other than Excluded Shares) of the Merger Consideration to be paid to such holders pursuant to the Merger Agreement. For purposes of its opinion, Centerview was not asked to, and Centerview did not, express any view on, and its opinion did not address, any other term or aspect of the Merger Agreement or the Transaction, including, without limitation, the structure or form of the Transaction, or any other agreements or arrangements contemplated by the Merger Agreement or entered into in connection with or otherwise contemplated by the Transaction, including, without limitation, the fairness of the Transaction or any other term or aspect of the Transaction to, or any consideration to be received in connection therewith by, or the impact of the Transaction on, the holders of any other class of securities, creditors or other constituencies of the Company or any other party. In addition, Centerview expressed no view or opinion as to the fairness (financial or otherwise) of the amount, nature or any other aspect of any compensation to be paid or payable to any of the officers, directors or employees of the Company or any party, or class of such persons in connection with the Transaction, whether

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relative to the Merger Consideration to be paid to the holders of the shares of Company Common Stock pursuant to the Merger Agreement or otherwise. Centerview’s opinion was necessarily based on financial, economic, monetary, currency, market and other conditions and circumstances as in effect on, and the information made available to Centerview as of, the date of Centerview’s written opinion, and Centerview does not have any obligation or responsibility to update, revise or reaffirm its opinion based on circumstances, developments or events occurring after the date of Centerview’ written opinion. Centerview’s opinion does not constitute a recommendation to any stockholder of the Company or any other person as to whether such stockholder should have executed a consent with respect to the Merger or as to how such stockholder or other person should otherwise act with respect to the Transaction or any other matter. Centerview’s financial advisory services and its written opinion were provided for the information and assistance of the members of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the Transaction. The issuance of Centerview’s opinion was approved by the Centerview Partners LLC Fairness Opinion Committee.

Summary of Centerview Financial Analysis

The following is a summary of the material financial analyses prepared and reviewed with the Board in connection with Centerview’s opinion, dated November 11, 2018. The summary set forth below does not purport to be a complete description of the financial analyses performed or factors considered by, and underlying the opinion of, Centerview, nor does the order of the financial analyses described represent the relative importance or weight given to those financial analyses by Centerview. Centerview may have deemed various assumptions more or less probable than other assumptions, so the reference ranges resulting from any particular portion of the analyses summarized below should not be taken to be Centerview’s view of the actual value of the Company. Some of the summaries of the financial analyses set forth below include information presented in tabular format. In order to fully understand the financial analyses, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses performed by Centerview. Considering the data in the tables below without considering all financial analyses or factors or the full narrative description of such analyses or factors, including the methodologies and assumptions underlying such analyses or factors, could create a misleading or incomplete view of the processes underlying Centerview’s financial analyses and its opinion. In performing its analyses, Centerview made numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of the Company or any other parties to the Transaction. None of the Company, Parent, Merger Sub or Centerview or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of the Company do not purport to be appraisals or reflect the prices at which the Company may actually be sold. Accordingly, the assumptions and estimates used in, and the results derived from, the financial analyses are inherently subject to substantial uncertainty. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before November 9, 2018 (the last trading day before the public announcement of the Transaction) and is not necessarily indicative of current market conditions.

Selected Public Company Analysis

Centerview reviewed certain financial information of the Company and compared it to corresponding financial information of certain publicly traded electronic health record (“EHR”) vendor and healthcare information technology (“HCIT”) vendor companies that Centerview deemed comparable, based on its experience and professional judgment, to the Company (referred to as the “selected companies” in this summary of Centerview’s opinion). Centerview viewed EHR and HCIT vendor companies as most comparable for purposes of its analysis due to, among other things, (1) the Company’s historical and projected revenue and operating margin profile (as set forth in the Adjusted Management Model) as compared to EHR and HCIT vendor companies (based on Wall Street research analyst consensus estimates) and (2) the Company’s mix of

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products and services currently offered to the Company’s customers and those services offered by EHR and HCIT vendor companies. Although none of the selected companies is directly comparable to the Company, the selected companies listed below were chosen by Centerview, among other reasons, because they are publicly traded companies with certain operational, business and/or financial characteristics that, for purposes of Centerview’s analysis, may be considered similar to those of the Company. However, because none of the selected companies is exactly the same as the Company, Centerview believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected public company analysis. Accordingly, Centerview also made qualitative judgments, based on its experience and professional judgment, concerning differences between the business, financial and operational characteristics of the Company and the selected companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis.

Using publicly available information obtained from SEC filings and other data sources as of November 9, 2018, Centerview calculated, among other things, for each selected company set forth below, the implied enterprise value (calculated, to the extent publicly available, as the market value of common equity (determined using the treasury stock method and taking into account outstanding in the money options, other equity awards and other convertible securities, as applicable) plus the face value of debt, preferred stock and non-controlling interests less cash and cash equivalents (excluding cash held on trust and restricted cash, as applicable) and equity investments) which is referred to in this summary of Centerview’s opinion as “EV”, as a multiple of Wall Street research analyst consensus estimated earnings before interest expense, income taxes, depreciation and amortization, stock-based compensation, and non-recurring items (which is referred to in this summary of Centerview’s opinion as “EBITDA”) for the next twelve-month period (which is referred to as “NTM”).

The results of this analysis are summarized as follows:

Based on the foregoing analysis and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a range of multiples of enterprise value to NTM EBITDA of

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10.5x to 12.5x. In selecting this range of multiples, Centerview made qualitative judgments based on its experience and professional judgment concerning differences between the business, financial and operating characteristics and prospects of the Company and the selected companies that could affect the public trading values in order to provide a context in which to consider the results of the quantitative analysis. Centerview applied this range to the Company’s NTM EBITDA of $430 million derived from the Forecasts, which resulted in a range of implied values per share of Company Common Stock of approximately $109.00 to $129.00, rounded to the nearest $1.00. Centerview also applied this range to the Company’s NTM EBITDA of $405 million derived from publicly available Wall Street research analyst consensus estimates for the next twelve-month period, which resulted in an implied per share equity value range per share of Company Common Stock of approximately $103.00 to $122.00, rounded to the nearest $1.00. Centerview compared these ranges to the Merger Consideration of $135.00 per share of Company Common Stock to be paid to the holders of shares of Company Common Stock (other than Excluded Shares) pursuant to the Merger Agreement.

Selected Transactions Analysis

Centerview reviewed and analyzed certain information relating to selected transactions involving publicly traded EHR and HCIT vendor companies that Centerview, based on its experience and professional judgment, deemed relevant to consider in relation to the Company and the Transaction. These transactions were selected, among other reasons, because their participants, size or other factors, for purposes of Centerview’s analysis, may be considered similar to the Transaction. Centerview used its experience, expertise and knowledge of these industries to select transactions that involved companies with certain operations, results, business mix or product profiles that, for purposes of this analysis, may be considered similar to certain operations, results, business mix or product profiles of the Company.

Financial data for the precedent transactions was based on publicly available information at the time of the announcement of the relevant transactions that Centerview obtained from public filings and other data sources. Using publicly available information, Centerview calculated, for each selected transaction set forth below, among other things, the enterprise value (calculated as described above) implied for the applicable target company based on the consideration payable in the applicable selected transaction as a multiple of the target company’s EBITDA for the latest twelve-month period (which is referred to in this summary as “LTM”) at the time of the transaction announcement.

The results of this analysis are summarized as follows:

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(1)  Utilized 2015 EBITDA

(2)  Utilized 2016 EBITDA

No company or transaction used in this analysis is identical or directly comparable to the Company or the Transaction. The companies included in the selected transactions listed above were selected, among other reasons, based on Centerview’s experience and professional judgment, because they have certain characteristics that, for the purposes of this analysis, may be considered similar to certain characteristics of the Company. The reasons for and the circumstances surrounding each of the selected transactions analyzed were diverse and there are inherent differences in the business, operations, financial conditions and prospects of the Company and the companies included in the selected transactions analysis. Accordingly, Centerview believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected transactions analysis. This analysis involves complex considerations and qualitative judgments concerning differences in financial and operating characteristics and other factors that could affect the public trading, acquisition or other values of the selected target companies and the Company.

Based on its analysis and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a range of multiples of enterprise value to LTM EBITDA of 14.0x to 17.0x derived from the target companies in the selected precedent transactions. In selecting this range of multiples, Centerview made qualitative judgments based on its experience and professional judgment concerning differences between the business, financial and operating characteristics and prospects of the Company and the target companies included in the selected transactions and other factors that could affect the public trading, acquisition or other values of such companies or the Company in order to provide a context in which to consider the results of the quantitative analysis. Centerview applied this range to the Company’s LTM EBITDA of $374 million for the period ended September 30, 2018 based on the Internal Data, which resulted in an implied per share equity value range for the shares of Company Common Stock of approximately $126.00 to $152.00, rounded to the nearest $1.00. Centerview compared this range to the Merger Consideration of $135.00 per share of Company Common Stock to be paid to the holders of shares of Company Common Stock (other than Excluded Shares) pursuant to the Merger Agreement.

Discounted Cash Flow Analysis

Centerview performed a discounted cash flow analysis of the Company based on the Forecasts. A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset by calculating the “present value” of estimated future cash flows of the asset. “Present value” refers to the current value of future cash flows or amounts and is obtained by discounting those future cash flows or amounts by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

In performing this analysis, Centerview calculated a range of equity values for the Company by (a) discounting to present value as of September 30, 2018 using discount rates ranging from 10.5% to 12.0%

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(reflecting Centerview’s analysis of the Company’s weighted average cost of capital) and the mid-year convention: (i) the forecasted fully taxed unlevered free cash flows of the Company over the period beginning October 1, 2018 and ending on December 31, 2022 (as calculated by Centerview as set forth in “—Certain Financial Projections Utilized in Connection with the Merger,” and (ii) a range of implied terminal values of the Company at the end of the Forecast period, calculated by Centerview applying an illustrative range of enterprise value to EBITDA multiples of 10.5x to 12.5x, which Centerview selected utilizing its professional judgment and experience, to the Company’s estimated forward EBITDA as of December 31, 2022, as set forth in the Forecasts, and (b) adding to the foregoing results the Company’s net cash as of September 30, 2018, as set forth in the Internal Data. Centerview divided the result of the foregoing calculations by the number of fully-diluted outstanding shares of Company Common Stock (determined using the treasury stock method and taking into account outstanding in-the-money options, restricted stock units and performance stock units) as of November 8, 2018 based on the Internal Data to derive a range of implied values per share of Company Common Stock of approximately $121.00 to $148.00, rounded to the nearest $1.00. Centerview compared this range to the Merger Consideration of $135.00 per share of Company Common Stock to be paid to the holders of shares of Company Common Stock (other than Excluded Shares) pursuant to the Merger Agreement.

Other Factors

Centerview noted for the Board certain additional factors solely for informational purposes, including, among other things, the following:

General

The preparation of a financial opinion is a complex analytical process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, a financial opinion is not readily susceptible to summary description. In arriving at its opinion, Centerview did not draw, in isolation, conclusions from or with regard to any factor or analysis that it considered. Rather, Centerview made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of the analyses.

Centerview’s financial analyses and opinion were only one of many factors taken into consideration by the Board in its evaluation of the Transaction. Consequently, the analyses described above should not be viewed as determinative of the views of the Board or management of the Company with respect to the Merger Consideration or as to whether the Board would have been willing to determine that a different consideration was fair. The consideration for the Transaction was determined through arm’s-length negotiations between the Company and Parent and was approved by the Board. Centerview provided advice to the Company during these negotiations. Centerview did not, however, recommend any specific amount of consideration to the Company or the Board or that any specific amount of consideration constituted the only appropriate consideration for the Transaction.

Centerview is a securities firm engaged directly and through affiliates and related persons in a number of investment banking, financial advisory and merchant banking activities. In the two years prior to the date of its written opinion, Centerview was not (except for its current engagement) engaged to provide financial advisory or other services to the Company, and Centerview did not receive any compensation from the Company during such

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period. In the two years prior to the date of its written opinion, Centerview was not engaged to provide financial advisory or other services to Parent, Veritas Capital Fund Management, L.L.C. (“Veritas”), the sponsor of Parent, or Elliott Management Corporation, a stockholder of the Company and Parent (“Elliott”), and Centerview did not receive any compensation from Parent, Veritas or Elliott during such period. Centerview may provide financial advisory and other services to or with respect to the Company, Parent, Veritas, Elliott or their respective affiliates and portfolio companies of such affiliates in the future, for which Centerview may receive compensation. Certain (i) of Centerview and Centerview’s affiliates’ directors, officers, members and employees, or family members of such persons, (ii) of Centerview’s affiliates or related investment funds and (iii) investment funds or other persons in which any of the foregoing may have financial interests or with which they may co-invest, may at any time acquire, hold, sell or trade, in debt, equity and other securities or financial instruments (including derivatives, bank loans or other obligations) of, or investments in, the Company, Parent, Veritas, Elliott or any of their respective affiliates and portfolio companies of such affiliates, or any other party that may be involved in the Transaction.

The Board selected Centerview as its financial advisor in connection with the Transaction based on, among other things, Centerview’s overall reputation and experience. Centerview is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Transaction.

In connection with Centerview’s services as the financial advisor to the Board, the Company has agreed to pay Centerview an aggregate fee of approximately $21 million, $3 million of which was payable upon the rendering of Centerview’s opinion, $7.5 million of which is payable upon the earlier of July 18, 2019 and the consummation of the Merger and the remainder of which is payable contingent upon consummation of the Transaction. In addition, the Company has agreed to reimburse certain of Centerview’s expenses arising, and to indemnify Centerview against certain liabilities that may arise, out of Centerview’s engagement.

Opinion of Lazard Frères & Co. LLC

Summary of Opinion

The Company retained Lazard to act as a financial advisor to the Company and to render an opinion to the Board as to the fairness, from a financial point of view, to holders of shares of Company Common Stock of the consideration to be paid to such holders in the Merger. On November 11, 2018, Lazard rendered its oral opinion to the Board, subsequently confirmed in writing, that, as of such date, and based upon and subject to the assumptions, procedures, factors, qualifications and limitations set forth therein, the Merger Consideration to be paid to holders of shares of Company Common Stock (other than Excluded Shares) in the Merger was fair, from a financial point of view, to such holders of shares of Company Common Stock.

The full text of Lazard’s written opinion, dated November 11, 2018, which sets forth the assumptions made, procedures followed, factors considered, and qualifications and limitations on the review undertaken by Lazard in connection with its opinion is attached to this proxy statement as Annex C and is incorporated into this proxy statement by reference. The description of Lazard’s opinion set forth in this proxy statement is qualified in its entirety by reference to the full text of Lazard’s written opinion attached as Annex C. We encourage you to read Lazard’s opinion and this section carefully and in their entirety.

Lazard’s opinion was for the benefit of the Board (in its capacity as such) in connection with the Board’s evaluation of the Merger and only addressed the fairness, from a financial point of view, to holders of shares of Company Common Stock (other than Excluded Shares) of the Merger Consideration to be paid to such holders of shares of Company Common Stock in the Merger as of the date of Lazard’s opinion. The Company did not request Lazard to consider, and Lazard’s opinion did not address, the relative merits of the Merger as compared to any other transaction or business strategy in which the Company might engage or the merits of the underlying decision by the Company to engage in the Merger. Lazard’s opinion was not intended to and does not constitute a recommendation to any holder of shares of Company Common Stock as to how such holder should vote or act with respect to the Merger or

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any matter relating thereto. Lazard’s opinion was necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Lazard as of, the date of Lazard’s opinion. Lazard assumed no responsibility for updating or revising its opinion based on circumstances or events occurring after the date of Lazard’s opinion. Lazard’s opinion did not express any opinion as to the price at which shares of Company Common Stock may trade at any time subsequent to the announcement of the Merger.

In connection with its opinion, Lazard:

Lazard assumed and relied upon the accuracy and completeness of the foregoing information, without independent verification of such information. Lazard did not conduct any independent valuation or appraisal of any of the assets or liabilities (contingent or otherwise) of the Company or concerning the solvency or fair value of the Company, and Lazard was not furnished with any such valuation or appraisal. Lazard was advised by the Company that the financial forecasts most recently prepared by the Company’s management, and presented to the Board best reflect the good faith judgments of the Board as to the Company’s future financial performance and, accordingly, Lazard was instructed to only use those forecasts for purposes of Lazard’s analysis in connection with its opinion. With respect to the projections utilized in Lazard’s analysis, Lazard assumed, with the consent of the Company, that they were reasonably prepared on bases reflecting the best currently available estimates and judgments as to the future financial performance of the Company. Lazard assumed no responsibility for, and expressed no view as to, such projections or the assumptions on which they were based.

In rendering its opinion, Lazard assumed, with the consent of the Company, that the Merger would be consummated on the terms described in the Merger Agreement, without any waiver or modification of any material terms or conditions of the Merger Agreement. Representatives of the Company advised Lazard, and Lazard assumed, that the Merger Agreement, when executed, would conform to the draft reviewed by Lazard in all material respects. Lazard also assumed, with the consent of the Company, that obtaining the necessary regulatory or third-party approvals and consents for the Merger would not have an adverse effect on the Company or the Merger. Lazard’s opinion did not address any legal, tax, regulatory or accounting matters, as to which Lazard understood that the Company obtained such advice as it deemed necessary from qualified professionals. Lazard expressed no view or opinion as to any terms or other aspects of the Merger (other than the Merger Consideration to the extent expressly specified in Lazard’s opinion). In addition, Lazard expressed no view or opinion as to the fairness of the amount or nature of, or any other aspects relating to, the compensation to any officers, directors or employees of any parties to the Merger, or class of such persons, relative to the Merger Consideration or otherwise.

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The following is a brief summary of the material financial analyses and reviews that Lazard deemed appropriate in connection with rendering its opinion. The brief summary of Lazard’s analyses and reviews provided below is not a complete description of the analyses and reviews underlying Lazard’s opinion. The preparation of a fairness opinion is a complex process involving various determinations as to the most appropriate and relevant methods of analysis and review and the application of those methods to particular circumstances, and, therefore, is not readily susceptible to summary description. Considering selected portions of the analyses and reviews or the summary set forth below, without considering the analyses and reviews as a whole, could create an incomplete or misleading view of the analyses and reviews underlying Lazard’s opinion.

In arriving at its opinion, Lazard considered the results of all of its analyses and reviews and did not attribute any particular weight to any factor, analysis or review considered by it. Rather, Lazard made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses and reviews.

For purposes of its analyses and reviews, Lazard considered industry performance, general business, economic, market and financial conditions and other matters, many of which are beyond the control of the Company. No company, business or transaction used in Lazard’s analyses and reviews as a comparison is identical to the Company or the Merger, and an evaluation of the results of those analyses and reviews is not entirely mathematical. Rather, the analyses and reviews involve complex considerations and judgments concerning financial and operating characteristics and other factors that could affect the acquisition, public trading or other values of the companies, businesses or transactions used in Lazard’s analyses and reviews. The estimates contained in Lazard’s analyses and reviews and the ranges of valuations resulting from any particular analysis or review are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than those suggested by Lazard’s analyses and reviews. In addition, analyses and reviews relating to the value of companies, businesses or securities do not purport to be appraisals or to reflect the prices at which companies, businesses or securities actually may be sold. Accordingly, the estimates used in, and the results derived from, Lazard’s analyses and reviews are inherently subject to substantial uncertainty.

The summary of the analyses and reviews provided below includes information presented in tabular format. In order to fully understand Lazard’s analyses and reviews, the tables must be read together with the full text of each summary. The tables alone do not constitute a complete description of Lazard’s analyses and reviews. Considering the data in the tables below without considering the full description of the analyses and reviews, including the methodologies and assumptions underlying the analyses and reviews, could create a misleading or incomplete view of Lazard’s analyses and reviews.

Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before November 9, 2018 (the last trading day before the public announcement of the Merger) and is not necessarily indicative of current market conditions.

Summary of Lazard Financial Analyses

Selected Public Company Analysis

For purposes of its analysis, Lazard reviewed and analyzed certain financial information, valuation multiples and market trading data related to the Company and selected comparable publicly traded companies whose operations Lazard believed, based on its experience with companies in the HCIT (including EHR) and Vertical SaaS (“Vertical SaaS”) industries and professional judgment, to be generally relevant in analyzing the Company’s operations. Lazard then compared such information to the corresponding information of the Company.

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The selected group of companies used in this analysis, which are referred to as “comparable companies,” was as follows:

EHR Companies

Other HCIT Companies

Vertical SaaS Companies

Lazard selected the companies reviewed in this analysis because, among other things, they operate businesses similar to one of the businesses of the Company. As compared to the HCIT Companies, Lazard viewed the Vertical SaaS Companies as being less relevant in its analysis of the Company’s operations as a result of, among other things (1) lower revenue growth that is forecasted for 2019 for the Company (as set forth in the Adjusted Management Model) as compared to the Vertical SaaS Companies (based on Wall Street research analyst consensus estimates) and (2) differences between the mix of software and processing services currently offered to the Company’s customers and those services offered by the Vertical SaaS Companies, which are more software focused. However, none of the selected companies is identical to the Company. Accordingly, Lazard believes that purely quantitative analyses are not, in isolation, determinative in the context of the Merger and that qualitative judgments concerning differences between the business, financial and operating characteristics and prospects of the Company and the comparable companies that could affect the public trading values of each also are relevant.

Lazard calculated each comparable company’s enterprise value (“EV”), which Lazard calculated as the market capitalization of each company (based on each company’s fully-diluted share count, and closing share price, as of November 9, 2018), plus balance sheet debt and other non-equity capitalization (if applicable) and less cash, cash equivalents and marketable securities to its estimated earnings before interest, taxes, depreciation and amortization (“EBITDA”) for the next twelve-month period (“NTM”). The NTM EBITDA estimates for each of the comparable companies used by Lazard in its analysis were based on public filings and information provided by FactSet Research Systems.

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The following tables summarize the results of this review:

Based on an analysis of the relevant metrics for each of the comparable companies (including the recent earnings and stock price performance of the EHR comparable companies), as well as its professional judgment and experience, Lazard applied an EV to NTM EBITDA multiple range of 10.5x-12.5x to the Company’s NTM EBITDA of $430 million as reflected in the Adjusted Management Model. Lazard also applied this range to the Company’s NTM EBITDA of $405 million derived from publicly available Wall Street research analyst consensus estimates that Lazard obtained from Wall Street research reports.

This analysis resulted in an implied price per share range for shares of Company Common Stock (rounded to the nearest $1.00), as compared to the Merger Consideration, as set forth below.

Selected Precedent Transactions Multiple Analysis

Lazard reviewed and analyzed selected precedent Merger and acquisition transactions involving HCIT and Vertical SaaS companies that it viewed, based on its experience and professional judgment, as generally relevant in analyzing the Company. In performing this analysis, Lazard reviewed certain financial information and transaction multiples relating to the companies involved in such selected transactions and compared such information to the corresponding information for the Company. Specifically, Lazard reviewed 19 merger and acquisition transactions involving companies in the HCIT industry for which sufficient public information was available, and 7 merger and acquisition transactions involving companies in the Vertical SaaS industry for which sufficient public information was available.

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The selected group of transactions reviewed in this analysis was as follows:

To the extent publicly available, Lazard also reviewed, among other things, (i) the EV to EBITDA multiple of each of the target companies implied by the selected transactions by comparing the enterprise implied by the acquisition price to the relevant target company’s estimated EBITDA for the NTM after each transaction was announced and (ii) the EV to EBITDA multiple of each of the target companies implied by the selected transactions by comparing the enterprise implied by the acquisition price to the relevant target company’s estimated EBITDA for the last twelve month period (“LTM”) before each transaction was announced. The EBITDA amounts for the target companies were based on publicly available company filings and Wall Street research analyst estimates. The following table summarizes the results of this review:

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Based on an analysis of the relevant metrics for each of the transactions, as well as its professional judgment and experience, Lazard applied an EV to NTM EBITDA multiple range of 13.0x-16.0x to the Company’s NTM EBITDA of $430 million as reflected in the Adjusted Management Model. Lazard also applied this range to the Company’s NTM EBITDA of $405 million derived from publicly available Wall Street research analyst consensus estimates that Lazard obtained from Wall Street research reports. Furthermore, based on an analysis of the relevant metrics for each of the transactions, as well as its professional judgment and experience, Lazard applied an EV to LTM EBITDA multiple range of 14.0x-17.0x to the Company’s LTM EBITDA of $374 million for the period ended September 30, 2018.

This analysis resulted in the following implied price per share ranges for shares of Company Common Stock (rounded to the nearest $1.00), as compared to the Merger Consideration, as set forth below.

Discounted Cash Flow Analysis

Lazard performed a discounted cash flow analysis of the Company, which is a valuation methodology used to derive a valuation of a company by calculating the present value of its estimated future cash flows. “Future cash flows” refers to projected unlevered free cash flows (calculated, beginning with unlevered net income, by adding depreciation and amortization, subtracting capital expenditures, expenditure on acquisitions, and adjusting for changes in working capital and other operating activities) of a company. “Present value” refers to the current value of future cash flows or amounts and is obtained by discounting those future cash flows or amounts by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, capital structure, income taxes, expected returns and other appropriate factors. Lazard calculated the discounted cash flow value of the Company as the sum of the net present value, as of September 30, 2018, of each of:

The estimated future cash flows for the Company over the period beginning October 1, 2018 and ending on December 31, 2022 were calculated by Lazard as set forth in “—Certain Financial Projections Utilized in Connection with the Merger”.

For its discounted cash flow calculations, Lazard applied discount rates ranging from 10.0% to 11.0%. Such discount rates were based on Lazard’s estimated ranges of the Company’s weighted average cost of capital, based on, among other things, the average unlevered risk profiles, weighted after-tax cost of debt and consolidated leverage ratios of the comparable companies described under “—Selected Public Company Analysis” above.

Lazard calculated the terminal value for the Company by applying EBITDA multiples ranging from 10.5x to 12.5x to the Company’s estimated terminal year EBITDA, implying a perpetuity growth rate range of 5.3% to 7.1%. The ranges of the multiples were selected by Lazard in its professional judgment by reference to the multiples of the comparable companies described under “—Selected Public Company Analysis” above.

The results of these analyses are summarized below:

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Lazard then added consolidated net cash to calculate a consolidated equity value range for the Company. Lazard divided the resulting consolidated equity value range by the fully diluted shares of Company Common Stock outstanding to calculate an implied price per share range (rounded to the nearest $1.00) and compared it to the Merger Consideration, as set forth below.

Other Analyses and Reviews

52-Week High/Low Trading Prices

Lazard reviewed the range of trading prices of shares of Company Common Stock for the 52 weeks ended on May 4, 2018 (the last full trading day prior to Elliott’s public proposal to acquire the Company for $160 per share). Lazard observed that, during such period, the closing share price of shares of Company Common Stock ranged from $101.00 per share to $156.00 per share (rounded to the nearest $1.00), as compared to the Merger Consideration of $135.00 per share of Company Common Stock.

Research Analyst Price Targets

Lazard reviewed selected equity analyst price targets based on publicly available Wall Street equity research reports published prior to November 9, 2018, which ranged from $128.00 to $180.00 per share of Company Common Stock, representing forward price targets (not discounted back). It was Lazard’s view, based on its professional judgment and experience, that these analyst price targets had been impacted by Elliott’s public proposal as well as significant press speculation regarding a sale of the Company. Lazard observed such range of price targets as compared to the Merger Consideration of $135.00 per share of Company Common Stock.

Miscellaneous

In connection with Lazard’s services as a financial advisor to the Company, the Company agreed to pay Lazard an aggregate fee of approximately $21 million, $3 million of which was payable upon the delivery of Lazard’s opinion, and approximately $18 million upon the consummation of the Merger. The Company also agreed to reimburse Lazard for certain expenses incurred in connection with Lazard’s engagement and to indemnify Lazard and certain related persons under certain circumstances against certain liabilities that may arise from or relate to Lazard’s engagement, including certain liabilities under U.S. federal securities laws.

Lazard, as part of its investment banking business, is continually engaged in the valuation of businesses and their securities in connection with mergers and acquisitions, negotiated underwritings, secondary distributions of listed and unlisted securities, private placements, leveraged buyouts, and valuations for estate, corporate and other purposes.

Lazard in the past have provided, currently is providing and in the future may provide certain investment banking services to the Company and certain companies in which Elliott Management Corporation (a stockholder of the Company and Parent) has an investment, for which we have received and may receive compensation. During the past two years, the financial advisory business of Lazard has provided advisory services to the Company (for which Lazard has received aggregate fees of approximately $1 million) and advisory services to two (2) companies in which Elliott holds less than a majority interest). During the past two years, the financial advisory business of Lazard was not engaged to provide financial advisory or other services to Veritas Capital Fund Management, L.L.C. (the sponsor of Parent (“Veritas”)) or any entity known to be an affiliate of Veritas, and Lazard did not receive any compensation from Veritas or any entity known to be an affiliate of Veritas. In addition, in the ordinary course, Lazard and its affiliates and employees may trade securities of the Company, Parent and certain of their respective affiliates for their own accounts and for the accounts of their customers,

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may at any time hold a long or short position in such securities, and may also trade and hold securities on behalf of the Company, Parent and certain of their respective affiliates. The issuance of Lazard’s opinion was approved by the opinion committee of Lazard.

Lazard is an internationally recognized investment banking firm providing a full range of financial advisory and other services. Lazard was selected to act as a financial advisor to the Company because of its qualifications, expertise and reputation in investment banking and mergers and acquisitions generally and in the healthcare and technology industries specifically, as well as its familiarity with the business of the Company.

The Company and Parent determined the total consideration of $135.00 in cash per share of Company Common Stock to be paid to the holders of shares of Company Common Stock pursuant to the Merger Agreement through arm’s-length negotiations, and the Board approved such consideration. Lazard did not recommend any specific consideration to the Board or any other person or indicate that any given consideration constituted the only appropriate consideration for the Merger. Lazard’s opinion was one of many factors considered by the Board, as discussed in “The Merger—Reasons for Recommending the Adoption of the Merger Agreement” beginning on page 36 of this proxy statement.

Interests of Directors and Executive Officers in the Merger

Members of the Board and our executive officers have various interests in the Merger described in this section that may be in addition to, or different from, the interests of athenahealth stockholders generally. You should keep this in mind when considering the recommendation of the Board for the adoption of the Merger Agreement. The members of the Board were aware of these interests and considered them at the time they approved the Merger Agreement and in making their recommendation that athenahealth stockholders adopt the Merger Agreement. These interests are described below.

Except as otherwise specifically noted, for purposes of quantifying the potential payments and benefits described in this section, the following assumptions were used:

The amounts indicated below are estimates based on multiple assumptions that may or may not actually occur or be accurate as of the date referenced, therefore, the actual amounts, if any, that may be paid or become payable may materially differ from the amounts set forth below.

Treatment of Outstanding Equity Awards

The Merger Agreement provides that, as of immediately prior to the Effective Time:

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Summary Tables

The following table sets forth number of shares of athenahealth common stock underlying outstanding vested Company Options, unvested Company Restricted Stock Units and unvested Company Performance Stock Units held by our non-employee directors and the cash proceeds that each of our non-employee directors would receive at or promptly after the Effective Time in respect of outstanding equity awards, whether or not vested, held by such non-employee director as of December 18, 2018. The table includes payments in respect of equity awards that may vest prior to the completion of the Merger based upon the completion of continued service with athenahealth and independent of the occurrence of the Merger. All share and unit numbers have been rounded to the nearest whole number. No non-employee director held any unvested Company Options as of December 18, 2018.

Director Equity Summary Table

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The following table sets forth the number of shares of athenahealth common stock underlying outstanding vested Company Options held by our executive officers and the cash proceeds that each of our executive officers would receive at or promptly after the Effective Time in respect of vested Company Options held by such executive officer as of December 18, 2018. No executive officer held any other vested equity awards as of December 18, 2018. All share numbers have been rounded to the nearest whole number.

Executive Officer Vested Equity Awards Summary Table

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(1) As of immediately prior to the Effective Time, with respect to each outstanding vested Company Option, (i) if the exercise price of such Company Option is equal to or greater than $135.00, such Company Option will be terminated and cancelled as of immediately prior to the Effective Time, without any consideration being payable in respect thereof, and (ii) if the exercise price of such Company Option is less than $135.00, such Company Option will be terminated and cancelled as of immediately prior to the Effective Time in exchange for the right to receive a lump sum cash payment in the amount equal to (i) the number of shares of athenahealth common stock underlying the Company Option immediately prior to the Effective Time, multiplied by (ii) $135.00 minus the applicable exercise price.

(2) The vested Company Options held by Mr. Haley and reported in this table have an exercise price equal to or greater than $135.00.

The following table sets forth the number of shares of athenahealth common stock underlying outstanding unvested Company Options, Company Restricted Stock Units and Company Performance Stock Units held by our executive officers and the cash proceeds that each of our executive officers would receive at or promptly after the Effective Time in respect of unvested Company Options, Company Restricted Stock Units and Company Performance Stock Units held by such executive officer as of December 18, 2018. All share numbers have been rounded to the nearest whole number.

Executive Officer Unvested Equity Awards Summary Table