PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

Filed by the Registrant ☒

Filed by a party other than the Registrant  ☐

Check the appropriate box:

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

 

You are cordially invited to virtually attend a special meeting (including any adjournments or postponements thereof, the “Special Meeting”) of stockholders of Stamps.com Inc. (“Stamps.com” or the “Company”) to be held on September 30, 2021 at 9:00 a.m., Pacific Daylight Time. This Special Meeting will be a “virtual meeting” conducted solely online. You will be able to attend the Special Meeting online by logging in at www.virtualshareholdermeeting.com/STMP2021SM.

At the Special Meeting, you will be asked to consider and vote on (i) a proposal to approve and adopt the Agreement and Plan of Merger, dated as of July 8, 2021 (as amended from time to time, the “Merger Agreement”), by and among Stamps.com, Stream Parent, LLC, a Delaware limited liability company (“Parent”), and Stream Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”), (ii) a proposal to approve, on an advisory (non-binding) basis, the compensation that may be paid or become payable to Stamps.com’s named executive officers (as defined in Item 402 of Regulation S-K) that is based on or otherwise related to the Merger Agreement and the transactions contemplated by the Merger Agreement (the “Compensation Proposal”), and (iii) a proposal to adjourn the Special Meeting from time to time, if necessary or appropriate as determined in the discretion of the board of directors of Stamps.com (the “Board of Directors”) or the Chairman of the Board of Stamps.com, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting (the “Adjournment Proposal”). Parent and Merger Sub are entities that are affiliated with Thoma Bravo, L.P., a private equity investment firm. Pursuant to the terms of the Merger Agreement, Merger Sub will merge with and into Stamps.com and the separate corporate existence of Merger Sub will cease, with Stamps.com continuing as the surviving corporation (the “Merger”) and a wholly owned subsidiary of Parent.

If the Merger is completed, you will be entitled to receive $330.00 in cash, less any applicable withholding taxes, for each share of Stamps.com common stock that you own (unless you have properly exercised your appraisal rights).

The Board of Directors, after considering the factors more fully described in the enclosed proxy statement, has unanimously: (1) determined that it is fair to and in the best interests of Stamps.com and its stockholders, and declared it advisable, to enter into the Merger Agreement and consummate the Merger on the terms and conditions set forth in the Merger Agreement; (2) approved, adopted and declared advisable the Merger Agreement and the execution and delivery of the Merger Agreement by Stamps.com, the performance by Stamps.com of its obligations and other agreements under the Merger Agreement, and the consummation of the Merger and the other transactions contemplated by the Merger, on the terms and conditions set forth in the Merger Agreement; (3) directed that the Merger Agreement and the Merger be submitted for approval and adoption by the stockholders of the Company; and (4) resolved to recommend that Stamps.com stockholders adopt the Merger Agreement and approve the Merger in accordance with the General Corporation Law of the State of Delaware. The Board of Directors unanimously recommends that you vote:

The enclosed proxy statement provides detailed information about the Special Meeting, the Merger Agreement and the Merger. A copy of the Merger Agreement is also attached as Annex A to the proxy statement.

The proxy statement describes the actions and determinations of the Board of Directors in connection with its evaluation of the Merger Agreement and the Merger. You should carefully read and consider the entire enclosed proxy statement and its annexes, including, but not limited to, the Merger Agreement, as they contain important information about, among other things, the Merger and how it affects you.

Whether or not you plan to virtually attend the Special Meeting in person, please sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). If you virtually attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy that you have previously submitted.

If you hold your shares in “street name,” you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your bank, broker or other nominee cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

Your vote is very important, regardless of the number of shares that you own. We cannot complete the Merger unless the proposal to adopt the Merger Agreement is approved by the affirmative vote of the holders of at least a majority of the outstanding shares of Stamps.com common stock entitled to vote at the Special Meeting.

If you have any questions or need assistance voting your shares, please contact our proxy solicitor:

D.F. King & Co, Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others Call Toll Free: (866) 745-0267

Email: [email protected]

On behalf of the Board of Directors, I thank you for your support and appreciate your consideration of this matter. Sincerely,

The accompanying proxy statement is dated August 30, 2021 and, together with the enclosed form of proxy card, is first being mailed on or about August 30, 2021.

 

Notice is hereby given that a special meeting of stockholders (including any adjournments or postponements thereof, the “Special Meeting”) of Stamps.com Inc., a Delaware corporation (“Stamps.com”), will be held on September 30, 2021 at 9:00 a.m., Pacific Daylight Time. This Special Meeting will be a “virtual meeting” conducted solely by means of remote communication. You will be able to attend the Special Meeting online by logging in at www.virtualshareholdermeeting.com/STMP2021SM. The Special Meeting is being called for the following purposes:

Only Stamps.com stockholders of record as of the close of business on August 26, 2021, are entitled to notice of the Special Meeting and to vote at, participate in and examine the Company’s list of stockholders at the Special Meeting.

The Board of Directors unanimously recommends that you vote: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

Whether or not you plan to virtually attend the Special Meeting in person, please sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). If you virtually attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy that you have previously submitted. If you hold your shares in “street name,” you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your bank, broker or other nominee cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions. If you sign, date and mail your proxy card without indicating how you wish to vote, your proxy will be counted as a vote “FOR” the adoption of the Merger Agreement, “FOR”, on an advisory (non- binding) basis, the Compensation Proposal and “FOR” the Adjournment Proposal, if necessary or appropriate.

WHETHER OR NOT YOU PLAN TO VIRTUALLY ATTEND THE SPECIAL MEETING IN PERSON, WE ENCOURAGE YOU TO SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE: (1) BY TELEPHONE; (2) THROUGH THE INTERNET; OR (3) BY SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE POSTAGE-PAID ENVELOPE PROVIDED. You may revoke your proxy or change your vote at any time before it is voted at the Special Meeting.

If you hold your shares in “street name,” you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form that you will receive from your bank, broker or other nominee. Your broker or other agent cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

If you are a Stamps.com stockholder of record, voting in person by ballot at the Special Meeting will revoke any proxy that you previously submitted. If you hold your shares through a bank, broker or other nominee, you must obtain a “legal proxy” in order to vote in person at the Special Meeting.

If you fail to (1) return your proxy card or voting instruction form, (2) grant your proxy electronically over the Internet or by telephone or (3) vote by ballot in person at the Special Meeting, your shares will not be counted for purposes of determining whether a quorum is present at the Special Meeting and, if a quorum is present, will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement but will have no effect on the Compensation Proposal or the Adjournment Proposal.

You should carefully read and consider the entire accompanying proxy statement and its annexes, including, but not limited to, the Merger Agreement, along with all of the documents incorporated by reference into the accompanying proxy statement, as they contain important information about, among other things, the Merger and how it affects you. If you have any questions concerning the Merger Agreement, the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of Stamps.com common stock, please contact our proxy solicitor:

D.F. King & Co, Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others Call Toll Free: (866) 745-0267

Email: [email protected]

Annexes

The following questions and answers address some commonly asked questions regarding the Merger, the Merger Agreement and the Special Meeting. These questions and answers may not address all questions that are important to you. You should carefully read and consider the more detailed information contained elsewhere in this proxy statement and the annexes to this proxy statement, including, but not limited to, the Merger Agreement, along with all of the documents we refer to in this proxy statement, as they contain important information about, among other things, the Merger and how it affects you. You may obtain the information incorporated by reference in this proxy statement without charge by following the instructions under the caption, “Where You Can Find More Information.”

If your shares are held through a broker, trustee or other nominee, it is likely that they are registered in the name of the nominee and you are the beneficial owner of shares held in street name. As the beneficial owner of shares held for your account, you have the right to direct the registered holder to vote your shares as you instruct. Your broker, trustee or other nominee has provided a voting instruction card for you to use in directing how your shares are to be voted. As a beneficial owner, you will need to obtain a “legal proxy” from your broker, trustee or other nominee to vote your shares online during the virtual Special Meeting. We will not be required to allow access to the Special Meeting to anyone that does not log in at www.virtualshareholdermeeting.com/STMP2021SM with valid credentials.

Once online access to the Special Meeting is open, shareholders may submit questions, if any, on www.virtualshareholdermeeting.com/STMP2021SM. You will need your unique control number included on your proxy card or on the instructions that accompanied your proxy materials. Questions pertinent to meeting matters will be answered during the meeting, subject to time constraints. As appropriate, we may answer some questions in writing and post the answers on our website following the Special Meeting. You may vote your shares at the Special Meeting even if you have previously submitted your vote.

Our Board decided to hold the Special Meeting virtually in response to public health concerns over, large gatherings of people in order to help limit potential transmission of COVID-19. Furthermore, our experience with virtual meetings demonstrated that the goals of accessibility and stockholder participation can be well served by the virtual format.

The exchange of Stamps.com common stock for cash in the Merger will be a taxable transaction for U.S. federal income tax purposes and may also be taxable under state and local and other tax laws. In general, you will recognize gain or loss equal to the difference between (1) the aggregate Per Share Merger Consideration you receive and (2) the adjusted tax basis of the shares of common stock you surrender in the Merger. If you are a Non-U.S. Holder, your exchange of shares of common stock for the Per Share Merger Consideration generally will not result in U.S. federal income tax unless you have certain connections with the United States. You should read the section entitled “The Merger - Material U.S. Federal Income Tax Consequences of the Merger” and consult your tax advisors regarding the U.S. federal income tax consequences of the Merger to you in your particular circumstances, as well as tax consequences arising under the laws of any state, local, or non-U.S. taxing jurisdiction.

If a quorum is present at the Special Meeting, the failure of any stockholder of record to vote his or her shares at the Special Meeting by: (1) submitting a signed proxy card; (2) granting a proxy over the Internet or by telephone (using the instructions provided in the enclosed proxy card); or (3) voting in person by ballot at the Special Meeting will have the same effect as a voting such shares “AGAINST” the proposal to adopt the Merger Agreement. If you hold your shares in “street name” and a quorum is present at the Special Meeting, the failure to instruct your bank, broker or other nominee how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement. If a quorum is present at the Special Meeting, abstentions will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement. Each “broker non-vote” (if any) will also count as a vote “AGAINST” the proposal to adopt the Merger Agreement but will have no effect on the Compensation Proposal or the Adjournment Proposal. If you properly sign your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy card will be voted: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

Under specified circumstances, Stamps.com will be required to pay Parent a termination fee of either $99,500,000 or $199,000,000, upon the termination of the Merger Agreement, as described in the section of this proxy statement captioned “Proposal 1: Adoption of the Merger Agreement—Termination Fee.”

If your shares are held through a bank, broker or other nominee, you are considered the “beneficial owner” of shares of Stamps.com common stock held in “street name.” In that case, this proxy statement has been forwarded to you by your bank, broker or other nominee. As the beneficial owner, you have the right to direct your bank, broker or other nominee how to vote your shares by following their instructions for voting. You are also invited to virtually attend the Special Meeting. However, because you are not the stockholder of record, you may not vote your shares in person at the Special Meeting unless you obtain a “legal proxy” from your bank, broker or other nominee.

A control number, located on your proxy card, is designed to verify your identity and allow you to vote your shares of Stamps.com common stock, and to confirm that your voting instructions have been properly recorded when voting electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). Please be aware that, although there is no charge for voting your shares, if you vote electronically over the Internet or by telephone, you may incur costs such as Internet access and telephone charges for which you will be responsible.

Even if you plan to virtually attend the Special Meeting in person, you are strongly encouraged to vote your shares of Stamps.com common stock by proxy. If you are a record holder or if you obtain a “legal proxy” to vote shares that you beneficially own, you may still vote your shares of Stamps.com common stock virtually in person by ballot at the Special Meeting even if you have previously voted by proxy. If you are virtually present at the Special Meeting and vote in person by ballot, your previous vote by proxy will not be counted.

If your shares are held in “street name” through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting form provided by your bank, broker or other nominee, or, if such a service is provided by your bank, broker or other nominee, electronically over the Internet or by telephone. To vote over the Internet or by telephone through your bank, broker or other nominee, you should follow the instructions on the voting form provided by your bank, broker or nominee.

If you hold your shares of Stamps.com common stock in “street name,” you should contact your bank, broker or other nominee for instructions regarding how to change your vote. You may also vote in person at the Special Meeting if you obtain a “legal proxy” from your bank, broker or other nominee.

If you properly sign your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy will be voted: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

You may receive more than one set of voting materials, including multiple copies of this proxy statement and multiple proxy cards or voting instruction cards. For example, if you hold your shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold shares. If you are a stockholder of record and your shares are registered in more than one name, you will receive more than one proxy card.

D.F. King & Co, Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others Call Toll Free: (866) 745-0267

Email: [email protected]

This proxy statement, and any documents to which Stamps.com refers to in this proxy statement, contains not only historical information, but also forward-looking statements made pursuant to the safe-harbor provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements represent Stamps.com’s current expectations or beliefs concerning future events, including but not limited to the expected completion and timing of the proposed transaction, expected benefits and costs of the proposed transaction, management plans and other information relating to the proposed transaction, strategies and objectives of Stamps.com for future operations and other information relating to the proposed transaction. Without limiting the foregoing, the words “believes,” “anticipates,” “plans,” “expects,” “intends,” “forecasts,” “should,” “estimates,” “contemplate,” “future,” “goal,” “potential,” “predict,” “project,” “projection,” “target,” “seek,” “may,” “will,” “could,” “should,” “would,” “assuming,” “depend” and similar expressions are intended to identify forward-looking statements. Stockholders are cautioned that any forward-looking statements are not guarantees of future performance and may involve significant risks and uncertainties, and that actual results may vary materially from those in the forward-looking statements. These risks and uncertainties include, but are not limited to, the risks detailed in our filings with the SEC, including in our most recent filings on Forms 10-K and 10-Q, factors and matters described or incorporated by reference in this proxy statement, and the following factors:

Consequently, all of the forward-looking statements that we make in this proxy statement are qualified by the information contained or incorporated by reference herein, including: (1) the information contained under this

caption; and (2) the information contained under the caption “Risk Factors,” and information in our consolidated financial statements and notes thereto included in our most recent filings on Forms 10-K and 10-Q. No assurance can be given that these are all of the factors that could cause actual results to vary materially from the forward-looking statements.

Except as required by applicable law, we undertake no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise. Stockholders are advised to consult any future disclosures that we make on related subjects as may be detailed in our other filings made from time to time with the SEC.

The enclosed proxy is solicited on behalf of the Board of Directors for use at the Special Meeting.

We will hold the Special Meeting on September 30, 2021 at 9:00 a.m., Pacific Daylight Time. This Special Meeting will be a “virtual meeting” conducted solely online. You will be able to attend the Special Meeting online by logging in at www.virtualshareholdermeeting.com/STMP2021SM.

At the Special Meeting, we will ask stockholders to vote on proposals to: (1) adopt the Merger Agreement; (2) approve, on an advisory (non-binding) basis, the Compensation Proposal; and (3) approve the Adjournment Proposal, if necessary or appropriate.

Only stockholders of record as of the Record Date are entitled to notice of the Special Meeting and to vote at the Special Meeting. A complete list of stockholders will be available for examination by any stockholder commencing no later than September 20, 2021 at our headquarters at 1990 E. Grand Ave., El Segundo, California 90245. If you would like to view the list, please contact our Investor Relations Department to schedule an appointment by calling (310) 482-5830. In addition, the list will be available for inspection by stockholders on the virtual meeting website during the meeting. As of the August 26, 2021 Record Date, there were 18,575,655 shares of Stamps.com common stock outstanding and entitled to vote at the Special Meeting.

The holders of a majority of the stock issued and outstanding and entitled to vote at the Special Meeting that are virtually present in person, by remote communication or represented by proxy, will constitute a quorum at the Special Meeting. In the event that a quorum is not present at the Special Meeting, it is expected that the meeting will be adjourned to solicit additional proxies.

The audio webcast of the Special Meeting will begin promptly at 9:00 a.m., Pacific Daylight Time. Online access to the audio webcast will open approximately thirty minutes prior to the start of the Special Meeting to allow time for you to log in and test your computer audio system. We encourage you to access the meeting prior to the start time.

As the Special Meeting is being conducted via an audio webcast, there is no physical meeting location. To attend the Special Meeting, log in at www.virtualshareholdermeeting.com/STMP2021SM. You will need your unique control number included on your proxy card or on the instructions that accompanied your proxy materials. We recommend that you log in a few minutes before the meeting to ensure you are logged in when the meeting starts. If you encounter any technical difficulties accessing the virtual meeting, a toll-free number will be available to assist.

Once online access to the Special Meeting is open, shareholders may submit questions, if any, on www.virtualshareholdermeeting.com/STMP2021SM. You will need your unique control number included on your proxy card or on the instructions that accompanied your proxy materials. Questions pertinent to meeting matters will be answered during the meeting, subject to time constraints. As appropriate, we may answer some questions in writing and post the answers on our website following the Special Meeting. You may vote your shares at the Special Meeting even if you have previously submitted your vote.

The affirmative vote of the holders of a majority of the outstanding shares of Stamps.com common stock is required to adopt the Merger Agreement. As of August 26, 2021, 9,287,828 votes constitute a majority of the outstanding shares of Stamps.com common stock. Adoption of the Merger Agreement by stockholders is a condition to the closing of the Merger.

The affirmative vote of the holders of a majority of the shares virtually present in person, by remote communication or represented by proxy at the Special Meeting and entitled to vote on the subject matter is required to approve, on an advisory (non-binding) basis, the Compensation Proposal.

Approval of the Adjournment Proposal whether or not a quorum is present, requires the affirmative vote of the holders of a majority of the shares virtually present in person, by remote communication or represented by proxy at the Special Meeting and entitled to vote on the subject matter.

If a stockholder abstains from voting, that abstention will have the same effect as if the stockholder voted “AGAINST” the proposal to adopt the Merger Agreement and “AGAINST” the proposal to approve each of the Compensation Proposal and the Adjournment Proposal.

Each “broker non-vote” (if any) will also count as a vote “AGAINST” the proposal to adopt the Merger Agreement but will have no effect on the Compensation Proposal or the Adjournment Proposal. A so-called “broker non-vote” results when banks, brokers and other nominees return a valid proxy voting upon a matter or matters for which the applicable rules provide discretionary authority but do not vote on a particular proposal because they do not have discretionary authority to vote on the matter and have not received specific voting instructions from the beneficial owner of such shares. Stamps.com does not expect any broker non-votes at the Special Meeting because the rules applicable to banks, brokers and other nominees only provide brokers with discretionary authority to vote on proposals that are considered routine, whereas each of the proposals to be presented at the Stamps.com Special Meeting is considered non-routine. As a result, no broker will be permitted to vote your shares of Stamps.com common stock at the Special Meeting without receiving instructions. Failure to instruct your broker on how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement.

As of August 26, 2021, our directors and executive officers beneficially owned and were entitled to vote, in the aggregate, 685,370 shares of Stamps.com common stock, representing approximately 3.69% of the shares of Stamps.com common stock outstanding as of August 26, 2021 (and own Company Options to acquire an additional 641,720 shares (of which 425,758 shares are currently vested), representing approximately 6.91% of the shares of Stamps.com common stock outstanding when taking into account Company Options held, in the aggregate, by our directors and executive officers).

Our directors and executive officers have informed us that they currently intend to vote all of their respective shares of Stamps.com common stock: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal. Certain executive officers, who hold an aggregate of 5,889 shares of Stamps.com common stock, representing less than 1% of our common stock at August 26, 2021, have entered into agreements to vote in favor of the Merger.

If your shares are registered in your name with our transfer agent, Computershare, you may cause your shares to be voted by returning a signed and dated proxy card in the accompanying prepaid envelope, or you may vote in person at the Special Meeting. Additionally, you may grant a proxy electronically over the Internet or by telephone (using the instructions provided in the enclosed proxy card). You must have the enclosed proxy card available and follow the instructions on the proxy card in order to grant a proxy electronically over the Internet or by telephone. Based on your proxy cards or Internet and telephone proxies, the proxy holders will vote your shares according to your directions.

If you plan to virtually attend the Special Meeting and wish to vote in person, a ballot will be available online at the Special Meeting. If your shares are registered in your name, you are encouraged to vote by proxy even if you plan to virtually attend the Special Meeting in person. If you attend the Special Meeting and vote in person by ballot, your vote will revoke any previously submitted proxy.

Voting instructions are included on your proxy card. All shares represented by properly signed and dated proxies received in time for the Special Meeting will be voted at the Special Meeting in accordance with the instructions of the stockholder. Properly signed and dated proxies that do not contain voting instructions will be voted: (1) “FOR” adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

If your shares are held in “street name” through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting form provided by your bank, broker or other nominee or attending the Special Meeting and voting in person with a “legal proxy” from your bank, broker or other nominee. If such a service is provided, you may vote over the Internet or telephone through your bank, broker or other nominee by following the instructions on the voting form provided by your bank, broker or other nominee. If you do not return

your bank’s, broker’s or other nominee’s voting form, do not vote via the Internet or telephone through your bank, broker or other nominee, if possible, or do not virtually attend the Special Meeting and vote in person with a “legal proxy” from your bank, broker or other nominee, it will have the same effect as if you voted “AGAINST” the proposal to adopt the Merger Agreement but will not have any effect on the Compensation Proposal or the Adjournment Proposal.

If you are a stockholder of record, you may change your vote or revoke your proxy at any time before it is voted at the Special Meeting by:

If you have submitted a proxy, your appearance at the Special Meeting will not have the effect of revoking your prior proxy; provided that you do not vote in person or submit an additional proxy or revocation, which, in each case, will have the effect of revoking your proxy.

If you hold your shares of Stamps.com common stock in “street name,” you should contact your bank, broker or other nominee for instructions regarding how to change your vote. You may also vote in person at the Special Meeting if you obtain a “legal proxy” from your bank, broker or other nominee.

Any adjournment, postponement or other delay of the Special Meeting, including for the purpose of soliciting additional proxies, will allow stockholders who have already sent in their proxies to revoke them at any time prior to their use at the Special Meeting, as adjourned, postponed or delayed.

The Board of Directors has unanimously: (1) determined that it is fair to and in the best interests of Stamps.com and its stockholders, and declared it advisable, to enter into the Merger Agreement and consummate the Merger on substantially the terms and conditions set forth in the Merger Agreement; (2) approved, adopted and declared advisable the Merger Agreement and the execution and delivery of the Merger Agreement by Stamps.com, the performance by Stamps.com of its obligations and other agreements under the Merger Agreement, and the consummation of the Merger and the other transactions contemplated by the Merger, on substantially the terms and conditions set forth in the Merger Agreement; (3) directed that the Merger Agreement and the Merger be submitted for approval and adoption by the stockholders of the Company; and (4) resolved to recommend that Stamps.com stockholders adopt the Merger Agreement and approve the Merger in accordance with the DGCL. The Board of Directors unanimously recommends that you vote: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

The expense of soliciting proxies will be borne by Stamps.com. We have retained D.F. King & Co, Inc. (“D.F. King”), a proxy solicitation firm, to solicit proxies in connection with the Special Meeting at a cost of approximately $15,000 plus expenses. We will also indemnify D.F. King against losses arising out of its provisions of these services on our behalf. In addition, we may reimburse banks, brokers and other nominees representing beneficial owners of shares for their expenses in forwarding soliciting materials to such beneficial owners. Proxies may also be solicited by our directors, officers and employees, personally or by telephone, email, fax, over the Internet or other means of communication. No additional compensation will be paid for such services.

Assuming timely satisfaction of necessary closing conditions, including the approval by stockholders of the proposal to adopt the Merger Agreement, we anticipate that the Merger will be consummated in the fourth calendar quarter of 2021.

If the Merger is consummated, stockholders who continuously hold shares of Stamps.com common stock through the Effective Time, who do not vote in favor of the adoption of the Merger Agreement and who properly demand appraisal of their shares and do not withdraw or waive their demands or otherwise lose their rights to seek appraisal will be entitled to seek appraisal of their shares in connection with the Merger under Section 262. This means that holders of shares of Stamps.com common stock who perfect their appraisal rights, who do not thereafter withdraw their demand for appraisal, and who follow the procedures in the manner prescribed by Section 262 may be entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash of the “fair value” of their shares of Stamps.com common stock, exclusive of any elements of value arising from the accomplishment or expectation of the Merger, as determined by the Delaware Court of Chancery, together with interest to be paid on the amount determined to be fair value, if any, (or in certain circumstances described in further detail in the section of this proxy statement captioned “The Merger— Appraisal Rights,” on the difference between the amount determined to be the fair value and the amount paid by the Surviving Corporation in the Merger to each stockholder entitled to appraisal prior to the entry of judgment in any appraisal proceeding). Due to the complexity of the appraisal process, stockholders who wish to seek appraisal of their shares are encouraged to review Section 262 carefully and to seek the advice of legal counsel with respect to the exercise of appraisal rights.

To exercise your appraisal rights, you must: (1) submit a written demand for appraisal to Stamps.com before the vote is taken on the adoption of the Merger Agreement; (2) not submit a proxy or otherwise vote in favor of the proposal to adopt the Merger Agreement; (3) continue to hold your shares of Stamps.com common stock of record through the Effective Time; and (4) strictly comply with all other procedures for exercising appraisal rights under Section 262. Your failure to follow exactly the procedures specified under Section 262 may result in the loss of your appraisal rights. In addition, the Delaware Court of Chancery will dismiss appraisal proceedings in respect of the Merger unless certain stock ownership conditions are satisfied by the stockholders seeking appraisal. The DGCL requirements for exercising appraisal rights are described in further detail in the section of this proxy statement captioned “The Merger—Appraisal Rights,” which is qualified in its entirety by Section 262, the relevant section of the DGCL regarding appraisal rights. A copy of Section 262 is reproduced and attached as Annex C to this proxy statement and incorporated herein by reference. If you hold your shares of Stamps.com common stock through a bank, brokerage firm or other nominee and you wish to exercise appraisal rights, you should consult with your bank, brokerage firm or other nominee to determine the appropriate procedures for the making of a demand for appraisal by such bank, brokerage firm or nominee.

If the Merger is completed, the shares of Stamps.com common stock will be delisted from Nasdaq and deregistered under the Exchange Act, and shares of Stamps.com common stock will no longer be publicly traded.

At this time, we know of no other matters to be voted on at the Special Meeting. If any other matters properly come before the Special Meeting, your shares of Stamps.com common stock will be voted in accordance with the discretion of the appointed proxy holders.

The proxy statement is available at https://investor.Stamps.com and clicking on the link titled “SEC Filings”.

Unless we have received contrary instructions, we may send a single copy of this proxy statement to any household at which two or more stockholders reside if we believe the stockholders are members of the same family. Each stockholder in the household will continue to receive a separate proxy card. This process, known as “householding,” reduces the volume of duplicate information received at your household and helps to reduce our expenses.

If you would like to receive your own set of our disclosure documents this year or in future years, please contact us using the instructions set forth below. Similarly, if you share an address with another stockholder and together both of you would like to receive only a single set of our disclosure documents, please contact us using the instructions set forth below.

If you are a stockholder of record, you may contact us by writing to Stamps.com at 1990 E. Grand Avenue, El Segundo, CA 90245. Eligible stockholders of record receiving multiple copies of this proxy statement can request householding by contacting us in the same manner. If a bank, broker or other nominee holds your shares, please contact your bank, broker or other nominee directly.

If you have any questions concerning the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of Stamps.com common stock, please contact our proxy solicitor:

D.F. King & Co, Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others Call Toll Free: (866) 745-0267

Email: [email protected]

This discussion of the Merger is qualified in its entirety by reference to the Merger Agreement, which is attached to this proxy statement as Annex A and incorporated into this proxy statement by reference. You should carefully read and consider the entire Merger Agreement, which is the legal document that governs the Merger, because this document contains important information about the Merger and how it affects you.

Stamps.com Inc.

Stamps.com is a leading provider of postage online and shipping software solutions to customers including consumers, small businesses, e-commerce shippers, enterprises, and high volume shippers. Stamps.com offers solutions that help businesses run their shipping operations more smoothly and function more successfully under the brand names Stamps.com, Endicia®, ShipStation®, ShippingEasy®, ShipWorks®, and MetaPack™. Stamps.com’s family of brands provides seamless access to mailing and shipping services through integrations with more than 500 unique partner applications. Stamps.com common stock is listed on Nasdaq under the symbol “STMP.”

Stream Parent, LLC

Parent was formed on July 2, 2021, solely for the purpose of engaging in the transactions contemplated by the Merger Agreement, and has not engaged in any business activities other than in connection with the transactions contemplated by the Merger Agreement and arranging of the equity financing and debt financing in connection with the Merger.

Stream Merger Sub, Inc.

Merger Sub is a wholly owned subsidiary of Parent and was formed on July 2, 2021, solely for the purpose of engaging in the transactions contemplated by the Merger Agreement, and has not engaged in any business activities other than in connection with the transactions contemplated by the Merger Agreement and arranging of the equity financing and debt financing in connection with the Merger.

Parent and Merger Sub are affiliates of the Thoma Bravo Fund, managed by Thoma Bravo. Thoma Bravo is a leading private equity investment firm focused on the software and technology-enabled services sectors. At the Effective Time, Stamps.com, as the Surviving Corporation, will be indirectly owned by the Thoma Bravo Fund.

In connection with the transactions contemplated by the Merger Agreement, the Thoma Bravo Fund has provided Parent with an equity commitment which, when taken together with the proceeds from the debt financing, is sufficient to fund the aggregate purchase price required to be paid at the closing of the Merger. In addition, the Thoma Bravo Fund has obtained a debt commitment sufficient to fund, together with cash on hand at Stamps.com, certain fees and expenses to be paid at the closing of the Merger, including any amounts required to terminate Stamps.com’s credit facility, subject to the terms and conditions of, the Merger Agreement. For more information, please see the section of this proxy statement captioned “—Financing of the Merger.”

Upon the terms and subject to the conditions of the Merger Agreement, Merger Sub will merge with and into Stamps.com and the separate corporate existence of Merger Sub will cease, with Stamps.com continuing as the Surviving Corporation. As a result of the Merger, Stamps.com will become a wholly owned subsidiary of Parent, and Stamps.com common stock will no longer be publicly traded and will be delisted from Nasdaq. In addition,

Stamps.com common stock will be deregistered under the Exchange Act, and we will no longer file periodic reports with the SEC. If the Merger is completed, you will not own any shares of the capital stock of the Surviving Corporation.

The Effective Time will occur upon the filing of a certificate of merger with the Secretary of State of the State of Delaware (or at such later time as we, Parent and Merger Sub may agree and specify in the certificate of merger).

If the Merger Agreement is not adopted by stockholders, or if the Merger is not completed for any other reason:

At the Effective Time, each share of Stamps.com common stock (other than Owned Company Shares or Dissenting Company Shares) outstanding as of immediately prior to the Effective Time will be cancelled and automatically converted into the right to receive the Per Share Price, less any applicable withholding of taxes.

At or prior to the Effective Time, Parent will deposit (or cause to be deposited) an amount of cash equal to the aggregate consideration with a designated payment agent for payment of each share of Stamps.com common stock owned by each Stamps.com stockholder. For more information, please see the section of this proxy statement captioned “Proposal 1: Adoption of the Merger Agreement—Exchange and Payment Procedures.”

After the Merger is completed, you will have the right to receive the Per Share Price in respect of each share of Stamps.com common stock that you own (less any applicable withholding of taxes), but you will no longer have any rights as a stockholder (except that stockholders who properly exercise their appraisal rights will have a right to receive payment of the “fair value” of their shares as determined pursuant to an appraisal proceeding, as contemplated by Delaware law). For more information, please see the section of this proxy statement captioned “—Appraisal Rights.”

The Board of Directors, with Stamps.com senior management, regularly and in the ordinary course of business, reviews and assesses Stamps.com’s long-term strategy, financial performance and operations in light of developments in Stamps.com’s business and overall developments in the industry in which it operates, taking into account the overall performance of the market and the mailing and shipping industries generally. As part of this ongoing review

and assessment, the Board of Directors considers various alternatives to Stamps.com’s long-term strategy, including alternatives involving possible strategic acquisitions to expand the markets and service offerings that Stamps.com provides, alternatives involving possible organic expansion into new markets and service offerings that Stamps.com provides, and alternatives involving possible strategic transactions and partnerships with third parties. Stamps.com regularly engages with its stockholders to discuss and to solicit feedback on their views and perspectives of Stamps.com’s long-term business plan, strategic opportunities and value.

In May 2017 representatives of Thoma Bravo contacted Mr. Ken McBride, CEO of Stamps.com, to express an interest in pursuing a transaction in which Thoma Bravo would acquire Stamps.com indicating it would be willing to pay a price of $135.00 per share. The closing market price per share of Stamps.com common stock during the month of May 2017 ranged from approximately $103 to $141. The Board of Directors discussed this indication of interest and the then current prospects for the Stamps.com’s business and determined not to proceed with any discussion or confidential information sharing with Thoma Bravo at that time.

In May 2019 representatives of Thoma Bravo contacted Mr. McBride to express an interest in pursuing a transaction in which Thoma Bravo would acquire Stamps.com indicating it would be willing to pay a price of $50.00 per share. The closing market price per share of Stamps.com common stock during the month of May 2019 ranged from approximately $34 to $87. The Board of Directors discussed this indication of interest and the then current prospects for the Stamps.com’s business and determined not to proceed with any discussion or confidential information sharing with Thoma Bravo at that time.

In August 2019, in connection with commercial discussions with an industry participant (“Industry Participant A”), Industry Participant A discussed the possibility of making an equity investment in Stamps.com. These discussions did not progress beyond preliminary or exploratory discussions and Industry Participant A indicated that it was not interested in further pursuing the discussions.

On March 2, 2021, financial sponsor (“Sponsor A”) contacted David Habiger, a director of Stamps.com, who had a prior relationship with a portfolio company of Sponsor A that concluded several years earlier, asking for an introduction to Mr. McBride. Mr. Habiger did not engage in any substantive discussions with Sponsor A and shortly thereafter made an introduction of Sponsor A to Mr. McBride.

On March 9, 2021 Sponsor A contacted Mr. McBride. The discussion addressed investor-related matters and did not discuss any potential acquisition of Stamps.com.

On April 14, 2021, Sponsor A sent Mr. McBride a preliminary, non-binding written indication of interest to acquire Stamps.com for a per share price range of $260 to $270 in cash, which represented a 25% to 30% premium to Stamps.com’s closing price as of April 13, 2021 and a 30% to 35% premium to Stamps.com’s 60-day volume weighted average trading price at that time. The proposal did not include any other material terms. Later that day, Mr. McBride shared the letter from Sponsor A with the Board of Directors and Proskauer Rose LLP (“Proskauer”), Stamps.com’s general outside legal counsel who from time to time has advised Stamps.com on a number of matters.

On April 21, 2021, the Board of Directors met virtually and discussed the indication of interest from Sponsor A. In the course of this meeting, Matthew Lipson, Chief Legal Officer of Stamps.com, provided the directors with an overview of their fiduciary duties. Mr. Habiger described Sponsor A’s outreach to him and how he made the introduction to Mr. McBride. Stamps.com senior management provided a summary of Sponsor A’s proposal. The Board of Directors discussed overall strategy to maximize stockholder value, including engaging in a sales process relative to other opportunities available to Stamps.com, the manner of conducting, and timing of, a sale process, valuation, business risks and other parties that could potentially be interested in acquiring Stamps.com. The Board also discussed the possibility of retaining a financial advisor and authorized management to approach a potential financial advisor in connection with a possible transaction. After discussion the Board of Directors instructed Mr. McBride to notify Sponsor A that it was rejecting the proposal at the proposed price range and to separately communicate to Sponsor A that the Board of Directors could potentially be open to considering a proposal at a higher valuation.

On April 21, 2021, Mr. McBride sent a letter to Sponsor A stating that at the price range indicated in Sponsor A’s proposal Stamps.com had no interest in pursuing a transaction. Mr. McBride the same day communicated telephonically with a representative of Sponsor A that the Board of Directors was open to considering other proposals

from Sponsor A, but at a higher valuation. That same day Sponsor A sent a letter to Mr. McBride requesting access to confidential information and time with management in order to revisit Sponsor A’s original offer price. Sponsor A also provided Stamps.com with a form of non-disclosure agreement.

Between April 22, 2021 and April 29, 2021, members of Stamps.com senior management, spoke with J.P. Morgan concerning its possible retention as financial advisor. Stamps.com senior management approached J.P. Morgan concerning the engagement given Stamps.com’s long-term relationship with J.P. Morgan, J.P. Morgan’s strength as a financial advisor and the historical and ongoing discussions Stamps.com senior management had with J.P. Morgan on a variety of topics including capital raising and mergers and acquisition transactions.

During the period between April 22, 2021 and April 29, 2021, J.P. Morgan provided a proposal for its engagement as a financial advisor and provided a draft of an engagement letter, which Stamps.com senior management and Proskauer negotiated with J.P. Morgan. J.P. Morgan also provided Stamps.com with a presentation, which, among other things addressed preliminary valuation perspectives, process alternatives for pursuing a transaction (including use of a post-signing “go-shop”) and a review of potential buyers, including highlighting Sponsor A, Thoma Bravo, and Industry Participant A as the most logical buyers, based largely upon the past interest such parties had expressed in a potential transaction with Stamps.com and in the case of Sponsor A and Thoma Bravo, the size and type of transactions such sponsors have historically pursued.

On April 22, 2021, Mr. McBride informed Sponsor A that the Board was reviewing its April 21, 2021 letter and list of requested due diligence items and provided Sponsor A with a form of non-disclosure agreement that Stamps.com would be willing to execute in order to provide Sponsor A access to Stamps.com confidential information.

On April 29, 2021, the Board of Directors met virtually, among other things, to discuss with Stamps.com’s senior management and Proskauer the process of considering strategic transactions and the retention of a financial advisor. At the meeting Proskauer made a presentation concerning the fiduciary duties of the Board of Directors in considering strategic transactions. Directors and members of Stamps.com senior management also discussed various options available to Stamps.com to enhance stockholder value. These considerations included Stamps.com’s continued operation as a standalone company, review of discussions to date with Sponsor A, and potential strategic transactions involving one or more other financial or industry participants. The Board also discussed the process going forward in connection with consideration of strategic transactions, the non-disclosure agreement, including the proposed standstill included in the form of non-disclosure agreement, and the diligence requests received from Sponsor A. Stamps.com senior management summarized for the Board of Directors the previously noted presentation that had been received from J.P. Morgan prior to the meeting concerning the potential process, preliminary valuation perspectives and the universe of potential buyers. In the presentation, J.P. Morgan had, as previously noted, indicated that the most logical buyers were Sponsor A, Thoma Bravo and Industry Participant A. Stamps.com senior management noted that both Thoma Bravo and Industry Participant A had previously expressed interest in making acquisition or investment proposals, as noted above. At this meeting Mr. Habiger expressly disclosed to the Board of Directors his conflict of interest involving Thoma Bravo, including that he was President of J.D. Power, which was a portfolio company of Thoma Bravo and that he had investments in several funds managed by Thoma Bravo. Mr. Habiger also expressly disclosed to the Board of Directors his prior relationship with a company owned by Sponsor A, which had concluded several years earlier. Having been informed regarding Mr. Habiger’s relationship to Thoma Bravo and his prior relationship with a company owned by Sponsor A and having considered the potential conflicts of interest implications, the Board of Directors determined to include Mr. Habiger in the ensuing meetings of the Board of Directors, with exceptions noted. The Board of Directors also reviewed the proposed final terms of engagement with J.P. Morgan, including the financial terms. Stamps.com senior management reviewed with the Board of Directors information J.P. Morgan had provided concerning its qualifications and experience. Following a discussion by the Board of Directors, the Board of Directors approved the retention of J.P. Morgan as its exclusive financial advisor in connection with any potential strategic transaction, subject to finalizing the proposed engagement letter, which was finalized and executed that same day. The Board then considered that Sponsor A and Thoma Bravo were among the best suited financial sponsors to make strong proposals. The Board noted that Thoma Bravo had shown interest in Stamps.com based on its proposals in 2017 and 2019. The Board also considered, after discussion with J.P. Morgan, whether the inclusion of two financial sponsors of the caliber, financial resources and relevant industry focus as Thoma Bravo and Sponsor A would be sufficient to test the market for financial sponsor interest and whether the potential benefits of conducting a broader marketing process was outweighed by the risks of distraction of management, the potential for leaks and disruption of existing commercial relationships. Stamps.com senior management also informed the Board of Directors that the J.P. Morgan presentation noted different process

alternatives that Stamps.com could pursue, including (i) moving forward with current parties with a “go-shop” arrangement, (ii) targeting outreach efforts to a limited number of additional potential buyers and/or (iii) conducting a broad confidential outreach to potential buyers. As the Board of Directors considered the valuation in the initial proposal from Sponsor A to be inadequate, the Board of Directors discussed using J.P. Morgan’s assistance in determining whether materially higher valuations might be obtainable. After a discussion, the Board of Directors authorized management, with advice from and in conjunction with J.P. Morgan, to engage in outreach to selected buyers by enabling due diligence reviews by Sponsor A pursuant to a non-disclosure agreement and initiating outreach to Thoma Bravo and, potentially, Industry Participant A, to determine whether they would be interested in making any strategic proposals and their willingness to agree to the use of a “go-shop” process.

On April 29, 2021, following the meeting of the Board of Directors, Stamps.com and Sponsor A entered into a non-disclosure agreement. The non-disclosure agreement contained standstill provisions but did not contain a prohibition on Sponsor A requesting a waiver of the standstill provisions, and expressly permitted Sponsor A to confidentially communicate to the Board of Directors, senior management of Stamps.com or its external financial advisors any non-public proposals regarding a potential transaction in a manner not reasonably expected to require public disclosure.

On May 1, 2021, Stamps.com provided Sponsor A access to the virtual dataroom containing a selected and limited set of information regarding Stamps.com.

On May 3, 2021, at the direction of Stamps.com, J.P. Morgan contacted representatives of Sponsor A to discuss Sponsor A’s due diligence requests, including scheduling live management sessions regarding business strategy and finance, financial forecasts and other data requests and the anticipated results for the fiscal quarter ended March 31, 2021.

On May 16 and 17, 2021, Mr. McBride contacted representatives of Thoma Bravo and told such representatives that Stamps.com would be willing to consider an indication of interest from Thoma Bravo if Thoma Bravo was willing to submit one.

On May 18, 2021, at the direction of Stamps.com, J.P. Morgan contacted Thoma Bravo regarding signing a non-disclosure agreement and providing Thoma Bravo’s access to due diligence information. That same day, at the direction of Stamps.com, J.P. Morgan provided Thoma Bravo with a non-disclosure agreement, which was executed on May 20, 2021. The non-disclosure agreement contained standstill provisions but did not contain a prohibition on Thoma Bravo requesting a waiver of the standstill provisions, and expressly permitted Thoma Bravo to confidentially communicate to the Board of Directors, senior management of Stamps.com or external financial advisors any non-public proposals regarding a potential transaction in a manner not reasonably expected to require public disclosure.

Between May 18, 2021 and June 9, 2021, Sponsor A and Thoma Bravo and their respective advisors and representatives conducted due diligence on Stamps.com. Stamps.com provided substantially the same information set to both parties. During this period, at the direction of Stamps.com, J.P. Morgan facilitated calls and virtual meetings with both Sponsor A and Thoma Bravo and the Company in order to address diligence requests and prepare both interested parties to provide proposals for the Board of Directors to consider. During this period, at the direction of Stamps.com, J.P. Morgan indicated to both sponsors that, at this time, if the Board of Directors made the decision to move ahead, it would require the sponsor to agree to a post-signing go-shop process.

On May 20, 2021, Stamps.com senior management hosted a meeting with Sponsor A to provide a detailed overview of Stamps.com’s business.

On May 26, 2021, Stamps.com senior management hosted a meeting with Thoma Bravo to provide a detailed overview of Stamps.com’s business.

On May 28, 2021, the Board of Directors met virtually, among other things, to receive an update from Stamps.com senior management regarding J.P. Morgan’s discussions with Sponsor A and Thoma Bravo.

On June 2, 2021, at the direction of Stamps.com, J.P. Morgan informed Sponsor A and Thoma Bravo that, having substantially concluded their respective due diligence processes, they should each be prepared to provide an updated proposal (in Sponsor A’s case) or an initial proposal (in Thoma Bravo’s case), in each case, regarding a potential

acquisition of Stamps.com. J.P. Morgan specifically noted, at the direction of Stamps.com, that since the Board of Directors would be deciding whether or not to proceed with either party regarding a potential strategic transaction, valuation was the single most important aspect of any revised or new proposal.

During early June 2021, Stamps.com conducted business and legal due diligence calls with both Sponsor A and Thoma Bravo.

On June 8, 2021 and June 9, 2021, Mr. McBride and J.P. Morgan contacted Industry Participant A to inform Industry Participant A of the existence of the outreach to selected buyers. A representative of Industry Participant A stated that it might consider an acquisition transaction through participation in the “go-shop” process but was unlikely to make any proposal at the current time.

On June 8, 2021, Sponsor A provided an updated nonbinding indication of interest to acquire Stamps.com for $260 per share, which was at the lowest end of the range that Sponsor A had proposed in its initial proposal on April 14, 2021. The Stamps.com closing price on the Nasdaq on June 7, 2021 was $191.96, and thus Sponsor A’s proposal reflected an approximately 36% premium to the price per share of Stamps.com common stock at such time, which was an increase from the premium in its initial proposal. The Sponsor A indication of interest proposed to fund the potential transaction with a majority equity contribution from Sponsor A’s funds and a limited set of certain of its limited partners, as well as borrowings from lenders. Sponsor A’s indication of interest did not offer a “go-shop,” did not request exclusivity and noted several additional confirmatory due diligence items it needed.

On June 8, 2021, Thoma Bravo provided a non-binding indication of interest to acquire Stamps.com for $270 per share, which reflected an approximately 41% premium to the closing price per share of Stamps.com common stock on June 7, 2021. The Thoma Bravo indication of interest proposed to fund the potential transaction with an equity contribution from Thoma Bravo’s funds (without the need to obtain equity from any co-investors), as well as borrowings from lenders. The Thoma Bravo indication of interest offered a 30 day “go-shop” and requested three weeks of exclusivity.

On June 9, 2021, the Board of Directors met virtually with senior management of Stamps.com, representatives of J.P. Morgan and representatives of Proskauer. Proskauer advised the Board on its fiduciary duties in this context. J.P. Morgan informed the Board of Directors it had provided services to both Sponsor A and Thoma Bravo and would provide a conflicts disclosure letter summarizing such services and the related fees earned, which it provided later that day. J.P. Morgan provided the Board of Directors with its preliminary valuation analysis of Stamps.com and its analysis of the financial terms of each of the Sponsor A and Thoma Bravo proposals. J.P. Morgan also summarized its work since its engagement, including discussions with Sponsor A, Thoma Bravo, Industry Participant A and facilitating due diligence. J.P. Morgan also provided the Board of Directors information about potential additional financial sponsors and strategic/industry bidders who could be invited to participate in the market outreach process. The presentation also covered various scenarios for additional outreach, and their respective advantages and disadvantages, including proceeding with the market outreach process with only Sponsor A and Thoma Bravo, broadening the market outreach process on a targeted basis or a further broadened market outreach process to a wide set of potential counterparties. J.P. Morgan noted various advantages and disadvantages with each of these approaches, including the risk of information leaks, the perception of Stamps.com being actively “shopped”, the impact on Stamps.com’s management’s attention and the risk of adversely impacting the interest and momentum with the current parties, as well as the ability to utilize a “go-shop” construct to solicit and actively engage with additional potential bidders after execution of a merger agreement.

The Board of Directors also discussed the status of discussions with Industry Participant A and Industry Participant A’s expressed preference to consider participation in a “go-shop” process rather than the current sales process. Additionally, the Board of Directors considered J.P. Morgan’s views as to the benefits and drawbacks of including other potential parties in a limited market outreach, and the strong competitive dynamic that could be engendered between Sponsor A and Thoma Bravo, and also considered the likelihood that any transaction would include a “go-shop” process, and decided that it was preferable to maintain the current process with only Sponsor A and Thoma Bravo. Given that the indications of interest from both Sponsor A and Thoma Bravo were nearly the same from a price perspective as Sponsor A’s initial proposal, the Board of Directors discussed with J.P. Morgan an approach to obtain materially higher proposals from both parties by potentially offering a limited period of exclusivity in a single round of bidding to the party that offered the highest and best valuation that was materially higher than the prior proposals. The Board of Directors then authorized J.P. Morgan to solicit the highest possible and best offer from Sponsor A and Thoma Bravo in a single round of bidding, in exchange for a limited period of

exclusivity, instructing them to provide updated indications of interest by the morning of June 10, 2021, including with a price per share of at least $280 (which would reflect a price per share floor of an approximately 46% premium to the closing price per share of Stamps.com common stock on June 7, 2021) and to confirm their willingness to agree to a “go-shop” process following execution of a definitive agreement with respect to a strategic transaction with Stamps.com.

On June 10, 2021, the Board of Directors met virtually with Stamps.com senior management and representatives of J.P. Morgan to review the proposals that were received that morning from Sponsor A and Thoma Bravo. Representatives of Proskauer were consulted throughout the ensuing bid process. Sponsor A provided an updated nonbinding indication of interest of $311 per share (which reflected an approximately 62% premium to the closing price per share of Stamps.com common stock on June 7, 2021), a 45-day “go-shop” period with a 1.5% break-up fee applicable during the “go-shop” period and a 3% fee applicable thereafter. In addition, Sponsor A required 28 days of exclusivity. Thoma Bravo provided an updated nonbinding indication of interest of $320 per share (which reflected an approximately 67% premium to the closing price per share of Stamps.com common stock on June 7, 2021) and a 40-day “go-shop” period and with similar break-up fee and exclusivity terms as Sponsor A’s $311 indication. Given the material increase in valuation indicated by both bidders and taking into account the preliminary valuation analysis provided by J.P. Morgan, and given that Thoma Bravo’s bid was $9.00 per share higher than Sponsor A’s bid, the Board of Directors determined that it was in the best interests of stockholders to grant exclusivity to Thoma Bravo. Although J.P. Morgan, at the instruction of the Board of Directors, had informed both bidders that each should make only a single bid, in order to obtain the highest possible price in exchange for exclusivity (and without any commitment by the Board of Directors to agree to any eventual transaction), before Stamps.com entered into exclusivity with Thoma Bravo, Sponsor A made a new unsolicited proposal of $330 per share (which reflected an approximately 72% premium to the closing price per share of Stamps.com common stock on June 7, 2021). Although the Board of Directors believed that Thoma Bravo had been the high bidder based on the parameters established for the bidding process, and that there was a risk of Thoma Bravo abandoning the process if Thoma Bravo believed that the Board of Directors was changing the process in response to a second bid by Sponsor A that was submitted after the single round of bidding, the Board of Directors, nevertheless, determined that it would be in the best interests of stockholders to treat the Sponsor A unsolicited bid as the new high bid, and accordingly the Board of Directors was prepared to enter exclusivity with Sponsor A unless Thoma Bravo matched or exceeded the price per share offered in Sponsor A’s second bid. In response, Thoma Bravo increased its proposal to $330 per share, without changing the other non-financial terms in its prior proposal. Given the fact that Thoma Bravo had initially been the high bidder, the high premium to Stamps.com’s current market price implied by the proposed price, and the fact that Thoma Bravo’s bid did not require equity co-investors as Sponsor A’s indication of interest had specified, the Board of Directors decided it was in the best interests of stockholders to grant exclusivity to Thoma Bravo based on the updated $330 price per share proposal. This price represented a premium of approximately 72% to Stamps.com’s closing price and 90-day volume weighted average price as of June 7, 2021. The exclusivity agreement with Thoma Bravo was entered into later in the day on June 10, 2021.

Over the next several weeks, Stamps.com senior management and representatives of Thoma Bravo and Thoma Bravo’s legal counsel, Kirkland & Ellis LLP (“Kirkland”), engaged in telephonic and virtual meetings to address the legal and business due diligence inquiries of Thoma Bravo and Kirkland regarding Stamps.com.

On June 11, 2021, senior management of Stamps.com authorized Proskauer to prepare a draft merger agreement with respect to the potential transaction with Thoma Bravo.

On June 11, 2021, representatives of Proskauer and Kirkland discussed a draft merger agreement, confirming that Proskauer would prepare the initial draft while Kirkland would focus on completing the legal due diligence process on behalf of Thoma Bravo.

During the period from June 14, 2021 to July 6, 2021, representatives of Stamps.com met on a regular basis with, and provided requested information to, representatives of Thoma Bravo and its advisors to provide information in connection with Thoma Bravo’s due diligence review of Stamps.com.

On June 24, 2021, representatives of Proskauer provided Kirkland an initial draft merger agreement. The draft merger agreement contemplated, among other things, (i) a 40-day “go-shop” period following the execution of the definitive agreement for Stamps.com to solicit and consider superior proposals with a related 1.5% termination fee for parties that constituted “Excluded Part[ies]” as defined in the merger agreement; (ii) a 3% termination fee for a superior proposal accepted after the “go-shop” period or for parties that did not constitute “Excluded Part[ies]” as defined

in the merger agreement; (iii) a 6% termination fee payable by Thoma Bravo if it failed to consummate the transactions under certain circumstances (a “reverse termination fee”); (iv) a best efforts covenant from both parties to secure regulatory approval of the transaction with a “hell or high water” required divestiture provision; (v) acceleration of all unvested stock options and restricted stock units; and (vi) other customary terms for a strategic transaction of this nature.

On July 2, 2021, representatives of Proskauer sent representatives of Kirkland a draft of the disclosure schedules to the draft merger agreement.

On July 2, 2021, representatives of Kirkland sent representatives of Proskauer a revised draft of the Stamps.com draft merger agreement. The revised draft merger agreement contained certain material revisions compared to the Stamps.com initial draft merger agreement, including, without limitation, (i) a requirement that all directors and officers sign voting agreements to vote their shares of Stamps.com common stock in favor of the merger concurrently with the execution of the merger agreement; (ii) a definition of “Excluded Party” that would have the effect that any offer during the “go-shop” period by a party that had previously made a written proposal (without any temporal limitation) to acquire Stamps.com prior to the signing of the merger agreement, such as Sponsor A, would (if the merger agreement were terminated to pursue such offer) trigger a 3% termination fee rather than the 1.5% termination fee that would be applicable to other parties; (iii) the removal of the “hell or high water” required divestiture provision; (iv) no acceleration of any unvested stock options or restricted stock units; (v) a requirement that Stamps.com reimburse up to $6 million of Thoma Bravo expenses incurred in connection with the proposed transaction if the stockholders of Stamps.com did not approve the merger as well as in other specified cases; and (vi) a 5% “reverse termination fee” if Thoma Bravo was unable to close the transaction due to not having the requisite debt financing.

On July 2, 2021, representatives of Kirkland sent representatives of Proskauer drafts of the other transaction documents, including an equity commitment letter, a limited guarantee and a voting agreement.

On or about July 3, 2021, representatives of Kirkland communicated in discussions with representatives of Proskauer that the modifications to the “Excluded Party” definition incorporated in Thoma Bravo’s July 1, 2021 draft of the merger agreement were critical to Thoma Bravo’s willingness to move forward with the transaction.

On July 6, 2021, the Board of Directors met virtually with senior management, representatives of J.P. Morgan and representatives of Proskauer. Proskauer advised the Board of Directors regarding its fiduciary duties in connection with the proposed transaction. Given his previously disclosed employment relationship with J.D. Power, a portfolio company of Thoma Bravo, Mr. Habiger excused himself from the Board of Directors meeting. Representatives of J.P. Morgan provided an update on Thoma Bravo’s diligence efforts and on their discussions with representatives of Thoma Bravo. Representatives of Proskauer summarized the legal and fiduciary issues presented by the changes to the merger agreement requested by Thoma Bravo and Kirkland, including Thoma Bravo and Kirkland’s continued resistance against a “hell or high water” antitrust covenant. Given the known lack of competitive business overlap between Stamps.com and Thoma Bravo’s portfolio companies, the “hell or high water” demand was deemed to be acceptable under the circumstances, and therefore the discussion focused on the definition of “Excluded Party.” The Board (with Mr. Habiger still being recused) engaged in an active discussion regarding the original purpose of the “go-shop” (namely to facilitate bids by parties who were not involved in pre-signing market outreach), the fact that Sponsor A had already been given several clear opportunities to be the higher bidder in the process of granting exclusivity, and in fact had caused Thoma Bravo to further increase its bid even after Thoma Bravo had been determined to be the highest and best bidder based on the single round of bidding of the original market outreach process, the fact that, based on the prior preliminary valuation analysis provided by J.P. Morgan, Thoma Bravo’s bid appeared to fully value Stamps.com at the highest end of all credible ranges, the fact that Thoma Bravo had made it clear that the “Excluded Party” provision proposed in its markup (and its implications on Sponsor A) was fundamental to its willingness to proceed with a transaction and the fact that Sponsor A had not made any outreach to Stamps.com since June 10, 2021 and that there was no assurance whatsoever that Sponsor A would be interested in making a “back up” offer should Thoma Bravo follow through on its credible threats of abandoning the process were this point not conceded by Stamps.com. Among other things, the Board was advised that Thoma Bravo had taken the position that unvested options and RSU Awards should not accelerate, that Thoma Bravo’s position was inconsistent with its original proposal which showed the capitalization of Stamps.com with all options and RSU Awards (whether vested or unvested) being exercised, and that Thoma Bravo was no longer raising acceleration of options or RSU Awards as an issue. In addition, representatives of Proskauer noted that there were various open points in the draft merger agreement where the Stamps.com draft provided the Board of Directors greater flexibility

than the Thoma Bravo revised draft, and that any concession made regarding the definition of “Excluded Party” could be paired with concessions by Thoma Bravo to enhance the Board of Director’s flexibility in any “go-shop” process and in the event of unsolicited bids. Based on these factors, the Board of Directors (again, with Mr. Habiger still recused) determined that continuing to negotiate the merger agreement with Thoma Bravo was in the best interests of stockholders and that the concession on the “Excluded Party” definition was necessary to avoid the likely loss of a valuable opportunity for stockholders, while also providing an opportunity to negotiate added changes to the merger agreement that would enhance the overall flexibility of the Board of Directors to utilize the “go-shop” process and reduce risk to Stamps.com. In addition, the Board of Directors (with Mr. Habiger participating) also recognized that, although there had not been any discussions between Thoma Bravo and management concerning continued employment of management and it had not authorized any discussions between Thoma Bravo and management regarding management compensation, Thoma Bravo might want to retain management in the event that a merger agreement was signed. The Board further recognized that in such event management would require independent counsel, and therefore authorized management to retain, as a corporate expense, independent counsel to represent it should management wish to negotiate with Thoma Bravo after a merger agreement was executed.

Later on July 6, 2021, representatives of Proskauer provided representatives of Kirkland a revised draft of the merger agreement which included the elements of the “Excluded Party” definition and the removal of the “hell or high water” antitrust clause which Thoma Bravo had indicated were threshold issues, but also made other changes to enhance the utility of the “go-shop” period. In addition, the parties negotiated a final “reverse termination fee” of 5.5% and resolved other remaining open points in the draft merger agreement and disclosure schedules.

Between July 2, 2021 and July 8, 2021, representatives of Proskauer and Kirkland negotiated the ancillary agreements to the draft merger agreement and the draft disclosure schedules. On July 7, 2021, representatives of Proskauer and Kirkland discussed the final open points in the merger agreement, and Thoma Bravo agreed to a further request that no director other than Ken McBride would be required to enter into a voting agreement in connection with the parties’ execution of the merger agreement.

On July 7, 2021, the Board of Directors met virtually with senior management, representatives of J.P. Morgan and representatives of Proskauer. Representatives of Proskauer provided an update on the merger agreement, the voting agreement and the “go-shop” period. The Board of Directors discussed the terms of the merger agreement with Proskauer and J.P. Morgan. Representatives of Proskauer presented a further update on the Board of Directors’ fiduciary duties.

On July 8, 2021, after market close, the Board of Directors held a meeting with representatives of Stamps.com senior management, Proskauer and J.P. Morgan. Representatives of J.P. Morgan reviewed for the Board of Directors a summary of the current status and financial terms of the acquisition proposal submitted by Thoma Bravo as set forth in the merger agreement and related documentation. Representatives of J.P. Morgan and Proskauer reviewed with the Board of Directors the key legal and financial terms of the Thoma Bravo $330 per share proposal, and representatives of J.P. Morgan then provided J.P. Morgan’s financial analyses of the Thoma Bravo $330 per share proposal. J.P. Morgan then rendered its oral opinion to the Board of Directors, which was subsequently confirmed by delivery of its written opinion, dated July 8, 2021, that, as of such date, and based upon and subject to the factors and assumptions set forth in its opinion, the $330 per share merger consideration (as proposed in the Thoma Bravo $330 per share proposal) to be paid to the Stamps.com common stockholders in the proposed Merger was fair, from a financial point of view, to such stockholders. For more information about J.P. Morgan’s opinion, see below under the caption “The Merger—Opinion of J.P. Morgan.” Representatives of Proskauer then provided a review for the Board of Directors of its fiduciary duties, and reviewed certain material terms of the proposed final merger agreement. Representatives of Proskauer answered questions from members of the Board of Directors regarding the terms of the proposed merger agreement and Stamps.com’s ability to conduct its business during the pendency of the Merger. The Board of Directors continued to discuss the potential transaction with Thoma Bravo and the reasons that the Board of Directors believed that it was in the best interests of Stamps.com and its stockholders to enter into the merger agreement with Thoma Bravo and consummate the Merger upon the terms and subject to the conditions set forth in the merger agreement. For more information concerning the recommendation of the Board of Directors, see the section titled “The Merger Agreement—Reasons for the Merger.” Mr. Habiger again reminded other members of the Board of Directors of his employment by J.D. Power, which is a Thoma Bravo portfolio company, and again recused himself from the meeting so that the Board of Directors could continue to discuss the Merger in an executive session. Following such discussion, Mr. Habiger rejoined the meeting and then the Board of Directors unanimously (i) determined that it was in the best interests of Stamps.com and its stockholders, and declared it advisable, to enter

into the merger agreement and consummate the Merger upon the terms and subject to the conditions set forth in the merger agreement; (ii) approved the execution and delivery of the merger agreement by Stamps.com, the performance by Stamps.com of its covenants and other obligations under the merger agreement, and the consummation of the Merger upon the terms and conditions set forth in the merger agreement; and (iii) resolved to recommend that Stamps.com stockholders adopt the merger agreement and approve the Merger in accordance with the DGCL.

Later that evening, Stamps.com and Thoma Bravo executed the merger agreement and related agreements entered into in connection with the transactions contemplated by the merger agreement. At the time of the execution of the merger agreement, Thoma Bravo and Stamps.com had not discussed the terms of any post-closing employment or equity participation for Stamps.com management, nor had any members of Stamps.com management had any such discussions with Thoma Bravo.

The following morning on July 9, 2021 before market open, Stamps.com issued a press release announcing the execution of the merger agreement.

Since the execution of the Merger Agreement, in connection with the “go-shop” period provided for in the Merger Agreement, which expired at 11:59 p.m. Pacific Time on August 17, 2021, at the direction of the Board of Directors, representatives of J.P. Morgan contacted and sought to engage in discussions with 35 parties regarding submitting an Acquisition Proposal, including Industry Participant A and Sponsor A with which Stamps.com had engaged prior to the execution of the Merger Agreement. 16 of the parties were financial parties and 19 of the parties were industry participants. In addition, J.P. Morgan received inquiries from two other potentially interested parties, one financial party and one industry participant, during the “go-shop” period. Stamps.com executed confidentiality agreements with three parties. None of the parties contacted or who made inquiries made an Acquisition Proposal.

The Board of Directors has unanimously: (1) determined that it is fair to and in the best interests of Stamps.com and its stockholders, and declared it advisable, to enter into the Merger Agreement and consummate the Merger on the terms and conditions set forth in the Merger Agreement; (2) approved, adopted and declared advisable the Merger Agreement and the execution and delivery of the Merger Agreement by Stamps.com, the performance by Stamps.com of its obligations and other agreements under the Merger Agreement, and the consummation of the Merger and the other transactions contemplated by the Merger, on the terms and conditions set forth in the Merger Agreement; (3) directed that the Merger Agreement and the Merger be submitted for approval and adoption by the stockholders of the Company; and (4) resolved to recommend that Stamps.com stockholders adopt the Merger Agreement and approve the Merger in accordance with the DGCL. The Board of Directors unanimously recommends that you vote: (1) “FOR” the adoption of the Merger Agreement; (2) “FOR”, on an advisory (non-binding) basis, the Compensation Proposal; and (3) “FOR” the Adjournment Proposal, if necessary or appropriate.

In the course of reaching its determination and recommendation, the Board of Directors consulted with Stamps.com management, Proskauer Rose LLP, its outside legal advisor, and J.P. Morgan, its financial advisor. The Board of Directors considered a number of factors, including those below (which are not listed in any relative order of importance), all of which it viewed as generally supporting its (i) approval of the execution and delivery of the Merger Agreement by Stamps.com, the performance by Stamps.com of its covenants and other obligations under the Merger Agreement, and the consummation of the Merger upon the terms and conditions set forth in the Merger Agreement; and (ii) resolution to recommend that Stamps.com stockholders adopt the Merger Agreement and approve the Merger in accordance with the DGCL:

The foregoing discussion of reasons for the recommendation to adopt the Merger Agreement and approve the Merger and the transactions contemplated thereby is not meant to be exhaustive but addresses the material information and factors considered by the Board of Directors in consideration of its recommendation. In view of the wide variety of factors considered by the Board of Directors in connection with its evaluation of the Merger and the complexity of these matters, the Board of Directors 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. Rather, in considering the information and factors described above, individual members of the Board of Directors each applied his or her own personal business judgment to the process and may have given differing weights to differing factors. The Board of Directors based its unanimous recommendation on the totality of the information presented. The explanation of the factors and reasoning set forth above contain forward-looking statements that should be read in conjunction with the section of this proxy statement entitled “Forward-Looking Statements.”

Pursuant to an engagement letter dated April 29, 2021, Stamps.com retained J.P. Morgan as its financial advisor in connection with the proposed Merger.

At the meeting of the Board of Directors on July 8, 2021, J.P. Morgan rendered its oral opinion to the Board of Directors that, as of such date and based upon and subject to the factors and assumptions set forth in its opinion, the Per Share Price to be paid to Stamps.com’s common stockholders in the proposed Merger was fair, from a financial point of view, to such stockholders. J.P. Morgan confirmed its July 8, 2021 oral opinion by delivering its written opinion to the Board of Directors of Stamps.com, dated July 8, 2021, that, as of such date, the Per Share Price to be paid to Stamps.com’s common stockholders in the proposed Merger was fair, from a financial point of view, to such stockholders.

The full text of the written opinion of J.P. Morgan dated July 8, 2021, which sets forth, among other things, the assumptions made, matters considered and limits on the review undertaken, is attached as Annex B to this proxy statement and is incorporated herein by reference. The summary of the opinion of J.P. Morgan set forth in this proxy statement is qualified in its entirety by reference to the full text of such opinion. Stamps.com’s stockholders are urged to read the opinion in its entirety. J.P. Morgan’s written opinion was addressed to the Board of Directors of Stamps.com (in its capacity as such) in connection with and for the purposes of its evaluation of the proposed Merger, was directed only to the Per Share Price to be paid in the proposed Merger and did not address any other aspect of the proposed Merger. J.P. Morgan expressed no opinion as to the fairness of the consideration paid to the holders of any class of securities, creditors or other constituencies of Stamps.com or as to the underlying decision by Company to engage in the proposed Merger. The issuance of J.P. Morgan’s opinion was approved by a fairness committee of J.P. Morgan. J.P. Morgan’s opinion does not constitute a recommendation to any stockholder of Stamps.com as to how such stockholder should vote with respect to the proposed Merger or any other matter.

In arriving at its opinion, J.P. Morgan, among other things:

In addition, J.P. Morgan held discussions with certain members of the management of Stamps.com and Parent with respect to certain aspects of the Merger, and the past and current business operations of Stamps.com, the financial condition and future prospects and operations of Stamps.com, and certain other matters J.P. Morgan believed necessary or appropriate to its inquiry.

In giving its opinion, J.P. Morgan relied upon and assumed the accuracy and completeness of all information that was publicly available or was furnished to or discussed with J.P. Morgan by Stamps.com and Parent or otherwise reviewed by or for J.P. Morgan, and J.P. Morgan did not independently verify (and did not assume responsibility or liability for independently verifying) any such information or its accuracy or completeness. J.P. Morgan did not conduct and was not provided with any valuation or appraisal of any assets or liabilities, nor did J.P. Morgan evaluate the solvency of Stamps.com, Parent or the Merger Sub under any applicable laws relating to bankruptcy, insolvency or similar matters. In relying on financial analyses and forecasts provided to J.P. Morgan or derived therefrom, J.P. Morgan assumed that they were reasonably prepared based on assumptions reflecting the best currently available estimates and judgments by management as to the expected future results of operations and financial condition of Stamps.com to which such analyses or forecasts relate. J.P. Morgan expressed no view as to such analyses or forecasts or the assumptions on which they were based. J.P. Morgan also assumed that the Merger and the other transactions contemplated by the Merger Agreement will be consummated as described in the Merger Agreement and this proxy statement, and that the definitive Merger Agreement would not differ in any material respect from the draft thereof

provided to J.P. Morgan. J.P. Morgan also assumed that the representations and warranties made by Stamps.com, Parent and Merger Sub in the Merger Agreement and the related agreements were and will be true and correct in all respects material to its analysis. J.P. Morgan is not a legal, regulatory or tax expert and relied on the assessments made by advisors to Stamps.com with respect to such issues. J.P. Morgan further assumed that all material governmental, regulatory or other consents and approvals necessary for the consummation of the Merger will be obtained without any adverse effect on Stamps.com or on the contemplated benefits of the Merger.

The projections furnished to J.P. Morgan were prepared by Stamps.com’s management. Stamps.com does not publicly disclose internal management projections of the type provided to J.P. Morgan in connection with J.P. Morgan’s analysis of the Merger, and such projections were not prepared with a view toward public disclosure. These projections were based on numerous variables and assumptions that are inherently uncertain and may be beyond the control of Stamps.com’s management, including, without limitation, factors related to general economic and competitive conditions and prevailing interest rates. Accordingly, actual results could vary significantly from those set forth in such projections. For more information regarding the use of projections and other forward-looking statements, please refer to the section entitled “The Merger—Company Financial Projection”.

J.P. Morgan’s opinion was necessarily based on economic, market and other conditions as in effect on, and the information made available to J.P. Morgan as of, the date of such opinion. J.P. Morgan’s opinion noted that subsequent developments may affect J.P. Morgan’s opinion, and that J.P. Morgan does not have any obligation to update, revise, or reaffirm such opinion. J.P. Morgan’s opinion is limited to the fairness, from a financial point of view, of the Per Share Price to be paid to Stamps.com’s common stockholders in the proposed Merger, and J.P. Morgan has expressed no opinion as to the fairness of any consideration to the holders of any other class of securities, creditors or other constituencies of Stamps.com or the underlying decision by Stamps.com to engage in the Merger. Furthermore, J.P. Morgan expressed no opinion with respect to the amount or nature of any compensation to any officers, directors, or employees of any party to the Merger, or any class of such persons relative to the consideration to be paid to Stamps.com’s common stockholders in the Merger or with respect to the fairness of any such compensation. J.P. Morgan expressed no opinion as to the price at which the common stock will trade at any future time.

The terms of the Merger Agreement, including the Per Share Price to be paid to Stamps.com’s common stockholders, were determined through arm’s length negotiations among Stamps.com, Parent and the Merger Sub, and the decision to enter into the Merger Agreement was solely that of Stamps.com’s Board of Directors. J.P. Morgan’s opinion and financial analyses were only one of the many factors considered by Stamps.com’s Board of Directors in its evaluation of the Merger and should not be viewed as determinative of the views of Stamps.com’s Board of Directors or management with respect to the Merger or the consideration.

In accordance with customary investment banking practice, J.P. Morgan employed generally accepted valuation methodology in rendering its opinion to Stamps.com’s Board of Directors on July 8, 2021 and contained in the presentation delivered to Stamps.com’s Board of Directors on such date in connection with the rendering of such opinion. The following is a summary of the material financial analyses utilized by J.P. Morgan in connection with rendering its opinion. The following summary, however, does not purport to be a complete description of the analyses or data presented by J.P. Morgan. Some of the summaries of the financial analyses include information presented in tabular format. The tables are not intended to stand alone, and in order to more fully understand the financial analyses used by J.P. Morgan, the tables must be read together with the full text of each summary. Considering the data set forth below without considering the full narrative description of the financial analyses, including the methodologies and assumptions underlying the analyses, could create a misleading or incomplete view of J.P. Morgan’s analyses. For each of the analyses performed by J.P. Morgan, J.P. Morgan utilized the treasury stock method to calculate fully diluted shares outstanding.

For each of the selected companies, J.P. Morgan calculated the multiple of firm value to estimated adjusted EBITDA for the 2022 calendar year (which we refer to as “CY2022E FV / Adj. EBITDA”). The multiples were based on the selected companies’ closing stock prices on July 7, 2021 and publicly available Wall Street analysts’ consensus estimates. The following table represents the results of this analysis:

Based on the results of this analysis and other factors J.P. Morgan considered appropriate, J.P. Morgan selected a multiple reference range of 9.0x to 19.0x for CY2022E FV / Adj. EBITDA, and applied this reference range to a CY2022E Adj. EBITDA for Stamps.com, as provided by Company management in its management projections. This resulted in an implied equity value range of $164.25 to $310.50 per share (in each case, rounded to the nearest $0.25) for Stamps.com, compared to (i) the closing price of the common stock on July 7, 2017 of $197.01 per share (which we refer to as the “Unaffected Price”), which was the last trading day prior to the public announcement of the Merger, and (ii) the merger consideration of $330.00 per share.

Based on the results of this analysis and other factors J.P. Morgan considered appropriate, J.P. Morgan selected a multiple reference range of 11.0x to 21.0x for FV / NTM Adj. EBITDA, and applied this reference range to the NTM Adj. EBITDA for Stamps.com, as provided by Stamps.com management in its management projections. This resulted in an implied equity value range of $178.25 to $310.00 per share (in each case, rounded to the nearest $0.25) for Stamps.com, compared to (i) the Unaffected Price and (ii) the merger consideration of $330.00 per share.

using a range of discount rates from 9% to 10%, which were chosen by J.P. Morgan based upon an analysis of the weighted average cost of capital of Stamps.com. The present value of the unlevered free cash flows and the range of terminal asset values were then adjusted by adding Stamps.com’s net cash balance of approximately $550 million as of June 30, 2021. Based on the results of this analysis, J.P. Morgan arrived at a range of equity values of between $225.00 and $287.25 per share of the common stock on a stand-alone basis (i.e., without synergies).

Analyses based upon forecasts of future results are inherently uncertain, as they are subject to numerous factors or events beyond the control of the parties and their advisors. Accordingly, forecasts and analyses used or made by J.P. Morgan are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by those analyses. Moreover, J.P. Morgan’s analyses are not and do not purport to be appraisals or otherwise reflective of the prices at which businesses actually could be acquired or sold. None of the selected companies reviewed as described in the above summary is identical to Stamps.com, and none of the selected transactions reviewed was identical to the Merger. However, the companies selected were chosen because they are publicly traded companies with operations and businesses that, for purposes of J.P. Morgan’s analysis, may be considered similar to those of Stamps.com. The transactions selected were similarly chosen because their participants, size and other factors, for purposes of J.P. Morgan’s analysis, may be considered similar to the Merger. The analyses necessarily involve complex considerations and judgments concerning differences in financial and operational characteristics of the companies involved and other factors that could affect the companies compared to Stamps.com and the transactions compared to the Merger.

As a part of its investment banking business, J.P. Morgan and its affiliates are continually engaged in the valuation of businesses and their securities in connection with mergers and acquisitions, investments for passive and control purposes, negotiated underwritings, secondary distributions of listed and unlisted securities, private placements, and valuations for corporate and other purposes. J.P. Morgan was selected to advise Stamps.com with respect to the Merger on the basis of, among other things, such experience and its qualifications and reputation in connection with such matters and its familiarity with Stamps.com and the industries in which it operates.

For services rendered in connection with the Merger, Stamps.com has agreed to pay J.P. Morgan an aggregate fee of approximately $48 million, $4 million of which became payable to J.P. Morgan at the time J.P. Morgan delivered its opinion and the remainder of which is contingent and payable upon the consummation of the Merger.. Stamps.com. In addition, Stamps.com has agreed to reimburse J.P. Morgan for its expenses incurred in connection with its services, including the fees and disbursements of counsel, and will indemnify J.P. Morgan against certain liabilities arising out of J.P. Morgan’s engagement.

During the two years preceding the date of J.P. Morgan’s opinion, neither J.P. Morgan nor its affiliates had any material financial advisory or other material commercial or investment banking relationships with Parent. During the two years preceding the date of J.P. Morgan’s opinion, J.P. Morgan and its affiliates have had commercial or investment banking relationships with Stamps.com for which J.P. Morgan and such affiliates have received customary compensation. Such services during such period have included acting as joint lead arranger and joint bookrunner on Stamps.com’s revolving credit facility in June 2020. During the two years preceding the date of J.P. Morgan’s opinion, J.P. Morgan and its affiliates have had commercial or investment banking relationships with certain affiliates of Thoma Bravo, LLC, an affiliate of Parent (“Thoma Bravo”) for which J.P. Morgan and such affiliates have received customary compensation. In addition, J.P. Morgan’s commercial banking affiliate is an agent bank and a lender under outstanding credit facilities of certain affiliates of Thoma Bravo, for which it receives customary compensation or other financial benefits. In addition, J.P. Morgan and its affiliates hold, on a proprietary basis, less than 1% of the outstanding common stock. During the two year period preceding delivery of J.P. Morgan’s opinion, the aggregate fees recognized by J.P. Morgan from Stamps.com were approximately $140,000 and from Thoma Bravo and certain of Thoma Bravo’s affiliates were approximately $96 million. In the ordinary course of their businesses, J.P. Morgan and its affiliates may actively trade the debt and equity securities or financial instruments (including derivatives, bank loans or other obligations) of Stamps.com for their own accounts or for the accounts of customers and, accordingly, they may at any time hold long or short positions in such securities or other financial instruments.

Although Stamps.com has in the past publicly issued limited short-term guidance concerning certain aspects of its expected financial performance, Stamps.com does not, as a matter of course, publicly disclose long-term forecasts or projections as to future performance, earnings or other results due to the inherent unpredictability of the underlying long-term assumptions, estimates and projections. However, Stamps.com is including certain previously nonpublic, unaudited prospective financial information prepared by its management for the calendar years 2021 to 2026 in order to provide Stamps.com stockholders with access to information that was made available to the Board of Directors in connection with its evaluation of the Merger. The Management Projections were presented to the Board of Directors on June 9, 2021 in connection with the Board of Directors’ consideration of proposals received by Stamps.com from Thoma Bravo and Sponsor A.

The following table presents the Management Projections:

Management Projections were developed by Stamps.com management on a standalone basis without giving effect to the Merger and the other transactions contemplated by the Merger Agreement, or any changes to Stamps.com’s operations or strategy that may be implemented after the consummation of the Merger, including any costs incurred in connection with the Merger and the other transactions contemplated by the Merger Agreement. Furthermore, the Management Projections do not take into account the effect of any failure of the transactions contemplated by the Merger Agreement to be completed and should not be viewed as accurate or continuing in that context. Management Projections are based on a number of assumptions which include, but are not limited to organic growth (i.e. no acquisitions); continued investments across Stamps.com’s businesses consistent with strategic initiatives; stable carrier economics and revenue sharing arrangements in the United States; anticipated carrier economics and revenue sharing arrangement in Stamps.com’s developing businesses outside of the United States; and no material fluctuations in interest rates and income taxes. Management Projections were based on information known to management as of May 16, 2021. In the view of Stamps.com management, the Management Projections have been reasonably prepared by Stamps.com management on bases reflecting the best currently available estimates and judgments of Stamps.com management of the future financial performance of Stamps.com at the time of the presentation to the Board of Directors and other matters covered thereby.

Although the Management Projections are presented with numerical specificity, they were based on numerous variables and assumptions made by Stamps.com management with respect to industry performance, general business, economic, regulatory, market and financial conditions and other future events, as well as matters specific to Stamps.com’s business, all of which are difficult or impossible to predict accurately and many of which are beyond Stamps.com’s control. The Management Projections constitute forward-looking information and are subject to many risks and uncertainties that could cause actual results to differ materially from the results forecasted in the Management Projections, including, but not limited to, Stamps.com’s performance, industry performance, general business and economic conditions, customer requirements, staffing levels, competition, adverse changes in applicable laws, regulations or rules, and the various risks set forth in Stamps.com’s reports filed with the SEC. There can be no assurance that the Management Projections will be realized or that actual results will not be significantly higher or lower than forecasted. The Management Projections cover several years, and such information by its nature becomes less reliable with each successive year. In addition, the Management Projections will be affected by Stamps.com’s ability to achieve strategic goals, objectives and targets over the applicable periods. The Management Projections reflect assumptions as to certain business decisions that are subject to change and cannot, therefore, be considered a guarantee of future operating results, and this information should not be relied on as such. The inclusion of the Management Projections should not be regarded as an indication that Stamps.com, J.P. Morgan, their respective officers, directors, affiliates, advisors, or other representatives or anyone who received this information then considered, or now considers, them a reliable prediction of future events, and this information should not be relied upon as such. The inclusion of the Management Projections in this proxy statement should not be regarded as an indication that the Management Projections will be necessarily predictive of actual future events. No representation is made by Stamps.com or any other person regarding the Management Projections or Stamps.com’s ultimate performance compared to such information. The Management Projections should be evaluated, if at all, in conjunction with the historical financial statements and other information about Stamps.com contained in Stamps.com’s public filings with the SEC. For more information, please see the section of this proxy statement captioned “Where You Can Find More Information.” In light of the foregoing factors, and the uncertainties inherent in the Management Projections, stockholders are cautioned not to place undue, if any, reliance on the Management Projections.

The Management Projections were not prepared with a view toward public disclosure or with a view toward complying with the published guidelines of the SEC regarding projections or accounting principles generally accepted in the United States (“GAAP”), or the guidelines established by the American Institute of Certified Public Accountants with respect to prospective financial information. At the direction of Stamps.com management, the non-GAAP financial measures used in the Management Projections were relied upon by J.P. Morgan for purposes of

its opinion and by the Board of Directors in connection with its evaluation of the Merger. The SEC rules which would otherwise require a reconciliation of a non-GAAP financial measure to a GAAP financial measure do not apply to non-GAAP financial measures included in disclosures relating to a proposed business combination such as the Merger if the disclosure is included in a document such as this proxy statement. Accordingly, Stamps.com has not provided a reconciliation of the financial measures included in the Management Projections to the relevant GAAP financial measures. 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 as used by Stamps.com may not be comparable to similarly titled amounts used by other companies. Neither Stamps.com’s independent auditor nor any other independent accountant has compiled, examined or performed any procedures with respect to the Management Projections, nor have they expressed any opinion or any other form of assurance on such information or its achievability.

The summary of the Management Projections is included solely to give stockholders access to the information that was made available to the Board of Directors, J.P. Morgan, Parent and Merger Sub, and is not included in this proxy statement in order to influence any stockholder to make any investment decision with respect to the Merger, including whether or not to seek appraisal rights with respect to their shares of Stamps.com common stock.

In addition, the Management Projections have not been updated or revised to reflect information or results after the date they were prepared or as of the date of this proxy statement, and except as required by applicable securities laws, Stamps.com does not intend to update or otherwise revise the Management Projections or the specific portions presented 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 underlying assumptions are shown to be in error.

When considering the recommendation of the Board of Directors that you vote to approve the proposal to adopt the Merger Agreement, you should be aware that our directors and executive officers may have interests in the Merger that are different from, or in addition to, the interests of stockholders generally, as more fully described below. The Board of Directors was aware of and considered these interests, among other matters, to the extent that they existed at the time, in approving the Merger Agreement and the Merger and recommending that the Merger Agreement be adopted by stockholders. These interests are described in more detail and, where applicable, are quantified in the narrative below.

As of the date of this proxy statement, none of our executive officers has entered into any agreement with Parent or any of its affiliates regarding employment with, or the right to purchase or participate in the equity of, the Surviving Corporation or one or more of its affiliates or otherwise provide any financing with respect to the Merger. Except as approved by the Board of Directors, from the date of the Merger Agreement, to the earlier of the termination of the Merger Agreement or the Effective Time, pursuant to the terms of the Merger Agreement, Parent and Merger Sub covenant not to, and covenant to not permit any of their subsidiaries or respective controlled affiliates to, authorize, make or enter into, any arrangements or understandings (formal or informal, binding or otherwise) with any executive officer of Stamps.com (1) regarding any continuing employment or consulting relationship with the Surviving Corporation; (2) pursuant to which any such executive officer would be entitled to receive consideration of a different amount or nature than Stamps.com stockholders; or (3) pursuant to which any such executive officer (directly or indirectly) would agree to provide equity investment to finance any portion of the Merger.

The Company’s executive officers as of the Effective Time are expected to continue to serve as officers of the Surviving Corporation and to continue to receive their salary and benefits. Under the Merger Agreement, for a period of 12 months after the Effective Time, Parent has agreed to provide each employee who continues with the Surviving Corporation salary, bonuses and certain benefits at least as favorable as provided prior to the Effective Time.

For a period of six years after the Effective Time, the Surviving Corporation will (and Parent will cause the Surviving Corporation to) indemnify, defend and hold harmless, and advance expenses to current or former directors, officers and employees of Stamps.com with respect to all acts or omissions by them in their capacities as such at any time

prior to the Effective Time (including any matters arising in connection with the Merger Agreement or the transactions contemplated thereby), to the fullest extent that Stamps.com would be permitted by applicable law and to the fullest extent required by the organizational documents of Stamps.com and as provided in any indemnification agreements as in effect prior to the Effective Time. For a period of six years after the Effective Time, the Surviving Corporation will (and Parent will cause the Surviving Corporation to) cause the certificate of incorporation, bylaws or other organizational documents of the Surviving Corporation to contain provisions with respect to indemnification, advancement of expenses and limitation of director, officer and employee liability that are no less favorable to the current or former directors, officers and employees of Stamps.com than those set forth in Stamps.com’s organizational documents as of the date of the Merger Agreement. The Surviving Corporation will not, for a period of six years from the Effective Time, amend, repeal or otherwise modify these provisions in the organizational documents in any manner that would adversely affect the rights of the current or former directors, officers and employees of Stamps.com.

The Merger Agreement also provides that, prior to the Effective Time, Stamps.com may purchase a six-year prepaid “tail” policy on the same terms and conditions as Parent would be required to cause the Surviving Corporation to purchase as discussed below. Stamps.com’s ability to purchase a “tail” policy is subject to a cap on the premium equal to 300% of the aggregate annual premiums currently paid by Stamps.com for its existing directors’ and officers’ liability insurance and fiduciary insurance for its last full fiscal year. If Stamps.com does not purchase a “tail” policy prior to the Effective Time, for at least six years after the Effective Time, Parent will cause the Surviving Corporation to maintain in full force and effect, on terms and conditions no less advantageous to the current or former directors, officers and employees of Stamps.com, the existing directors’ and officers’ liability insurance and fiduciary insurance maintained by Stamps.com as of the date of the Merger Agreement. The “tail” policy will cover claims arising from facts, events, acts or omissions that occurred at or prior to the Effective Time, including the transactions contemplated in the Merger Agreement. The obligation of Parent or the Surviving Corporation, as applicable, is subject to an annual premium cap of 300% of the aggregate annual premiums currently paid by Stamps.com for such insurance, but if the costs exceed such cap, Parent or the Surviving Corporation will purchase as much of such insurance coverage as possible for such amount. For more information, please see the section of this proxy statement captioned “Proposal 1: Adoption of the Merger Agreement—Indemnification and Insurance.”

The Company from time to time has granted Company Options and Company RSU Awards under its 2010 Equity Incentive Plan, as amended, 2016 ShippingEasy Equity Inducement Plan, February 26, 2018 Equity Inducement Award, 2018 Metapack Equity Inducement Award and 1999 Employee Stock Purchase Plan (as amended from time to time through October 24, 2018) (collectively, the “Company Equity Plans”).

At the Effective Time, each Company Option (whether vested or unvested) will be cancelled and automatically converted into the right to receive an amount in cash without interest, equal to the product of (A) the aggregate number of shares of Stamps.com common stock subject to such Company Option, multiplied by (B) the excess, if any, of the Per Share Price over the applicable per share exercise price under such Company Option, subject to any required withholding of Taxes.

No new purchase intervals will begin or be extended under the ESPP after July 8, 2021, and the ESPP will terminate immediately prior to, and effective as of, the Effective Time. In addition, no new participants will be permitted in the ESPP following July 8, 2021, or as soon as administratively practicable thereafter, and with respect to any purchase intervals in effect on July 8, 2021, as of and following such date, existing participants in the ESPP will not be allowed to increase payroll contribution rates or make separate non-payroll contributions to the ESPP, except as required by applicable law.

Any Company Option (whether vested or unvested) with a per share exercise price equal to or greater than $330.00 will be cancelled immediately upon the Effective Time without payment or consideration.

Each Company RSU Award (whether vested or unvested) that is outstanding as of immediately prior to the Effective Time shall accelerate and become fully vested effective immediately prior to, and contingent upon, the Effective Time, and shall be cancelled and automatically converted into the right to receive an amount in cash, without interest, equal to the product of (A) the aggregate number of shares of Stamps.com common stock subject to the Company RSU Award multiplied by (B) the Per Share Price, subject to any required withholding of Taxes.

The Company Equity Plans will terminate as of the Effective Time and the provisions in any other employee plan or contract providing for the issuance or grant of any other interest in respect of the capital stock of Stamps.com will be cancelled as of the Effective Time.

We have entered into an agreement with Mr. McBride that could result in the payment of compensation and benefits to Mr. McBride following a change in control. Mr. McBride and the Company have agreed that, in the event of (i) an involuntary termination by us without cause following a change in control or (ii) a resignation by Mr. McBride within two to nine months following the change in control, he will receive a lump sum payment equal to six months of his then-current base salary and Company-provided health and welfare benefits for a period of six months following his termination. Except in the event of a change of control, no amounts would be due to any of our named executive officers in the event of a resignation or a termination with cause.

In connection with the Merger, the Company may take certain actions to mitigate any potential adverse tax consequences to the Company and certain employees of the Company under the “golden parachute” provisions of Sections 280G and 4999 of the Code that could arise in connection with the completion of the Merger. Specifically, the Company is permitted to enter into agreements with any “disqualified person” (as defined under Section 280G of the Code and the regulations thereunder, and which includes our executive officers) containing a “net best” provision such that in the event that a disqualified person becomes subject to the excise tax imposed under Section 4999 of the Code, any parachute payments will be reduced to the safe harbor limit so that the excise tax is not triggered, unless the net after tax value of the amounts due to the disqualified person after imposition of the excise tax would be greater than the net after tax value of the reduced amount (in which case no reduction will apply). The Company does not expect that any of our executive officers will be subject to the excise tax imposed under Section 4999 of the Code.

This section sets forth the information required by Item 402(t) of Regulation S-K regarding the compensation for each of Stamps.com’s named executive officers that is based on or otherwise relates to the Merger. This compensation is referred to as “golden parachute compensation” by the applicable SEC disclosure rules. The amounts set forth in the table below are estimates based on multiple assumptions that may or may not actually occur, including assumptions described in this proxy statement and in the footnotes to the table. As a result, the actual amounts, if any, that a named executive officer receives may materially differ from the amounts set forth in the table.

The table below assumes that: (i) the Effective Time of the Merger will occur on October 4, 2021; (ii) the employment of Mr. McBride will be terminated immediately following the Effective Time of the Merger in a manner entitling him to receive the severance benefits described in the section of this proxy statement captioned “—Potential Payments At or Following Change in Control”; and (iii) no named executive officer becomes entitled to additional compensation or benefits or equity awards prior to the Effective Time of the Merger. Pursuant to applicable proxy disclosure rules, the value of the equity award vesting acceleration below is equal to the number of shares covered by the applicable Company Option or Company RSU Award that are accelerating multiplied by the Per Share Price. The amounts shown in the table below do not include the value of payments or benefits that would have been earned, or any amounts associated with equity awards that would vest pursuant to their terms, on or prior to the Effective Time of the Merger, or the value of payments or benefits that are not based on or otherwise related to the Merger.

As described in the footnotes to the amounts shown in the table below, the cash payments to Mr. McBride and the benefits that may be provided to Mr. McBride are conditioned on the occurrence of both the Merger, as well as his qualifying termination of employment (a “double-trigger” basis), and the other amounts in the table are conditioned only upon the occurrence of the Merger (a “single-trigger” basis).

At the Effective Time of the Merger, each Company Option and Company RSU Award held by our executive officers and non-employee directors will receive the treatment described in the section of this proxy statement captioned “Treatment of Company Options and Company RSU Awards.”

Each of our executive officers is eligible to receive the applicable vesting acceleration benefits with respect to his or her equity awards described above under the heading “—Potential Payments At or Following Change in Control.”

At the Effective Time each unvested equity award held by Stamps.com’s non-employee directors will become fully vested and, as applicable, exercisable pursuant to the terms of Stamps.com’s Non-Employee Director Compensation Policy.

The following table sets forth the number of shares of common stock and the number of shares of common stock underlying equity awards held by each of Stamps.com’s executive officers and non-employee directors that are outstanding as of August 26, 2021, the latest practicable date to determine such amounts before the filing of this proxy statement. Such numbers do not forecast any grants, additional issuances, dividends, additional deferrals or forfeitures of equity-based awards following the date of this proxy statement. However, such numbers take into account the vesting of equity awards that may become vested on or prior to October 4, 2021. The table also sets forth the values of these shares and equity awards, determined as the number of shares multiplied by the Per Share Price (minus the applicable per share exercise price for any Company Options). No additional shares of common stock or equity awards were granted to any executive officer or non-employee director in contemplation of the Merger.

The obligation of Parent and Merger Sub to consummate the Merger is not subject to any financing condition.

We anticipate that the total amount of funds necessary to complete the Merger and the related transactions, and to pay the fees and expenses required to be paid at the closing of the Merger by Parent and Merger Sub under the Merger Agreement, will be approximately $6.6 billion. This amount includes the funds needed to: (1) pay stockholders the amounts due under the Merger Agreement and (2) make payments in respect of our outstanding equity-based awards pursuant to the Merger Agreement.

Pursuant to the Equity Commitment Letter, the Thoma Bravo Fund has agreed to provide Parent with an equity commitment which, when taken together with the proceeds from the debt financing, is sufficient to fund the aggregate purchase price required to be paid at the closing of the Merger, including (A) the aggregate consideration to which the holders of Stamps.com common stock become entitled pursuant to the Merger Agreement, (B) the cash consideration to be paid in connection with the Company RSU Awards and (C) the cash consideration to be paid in connection with the Company Options. The Equity Commitment Letter provides, among other things, that:

(1) Stamps.com is an express third party beneficiary thereof with respect to enforcing Parent’s right to cause the equity commitment under the Equity Commitment Letter by the Thoma Bravo Fund to be funded to Parent in order to consummate the Merger, if, and only if, (a) all conditions in Article VII of the Merger Agreement have been satisfied or waived (other than any conditions that by their nature are to be satisfied at the closing of the Merger, but subject to the prior or substantially concurrent satisfaction of such conditions), (b) the Debt Financing (as defined below) has been funded in accordance with the terms and conditions thereof or will be funded in accordance with the terms and conditions thereof if the Equity Financing is funded and (c) Stamps.com has irrevocably confirmed in writing that if the Equity Financing and Debt Financing are funded, then Stamps.com shall take such actions that are required of it by the Merger Agreement to consummate the closing of the Merger pursuant to the terms of the Merger Agreement; and (2) Parent and the Thoma Bravo Fund each waive any defenses to the enforceability of remedies, subject to enforceability limitations, and will not oppose the granting of an injunction, specific performance or other equitable relief on the basis that (x) there is adequate remedy at law or (y) an award of specific performance is not an appropriate remedy for any reason at law or in equity. The Equity Commitment Letter may not be amended or otherwise modified without the prior written consent of Parent, the Thoma Bravo Fund and Stamps.com.

In addition, in connection with the Merger Agreement, Parent entered into the Debt Commitment Letter with the Debt Commitment Parties, pursuant to which the Debt Commitment Parties have committed to provide, upon certain terms and subject to certain conditions, Merger Sub with certain debt financing.

A portion of the proceeds under this debt financing will be used for all fees and expenses to be paid at the closing of the Merger by Stamps.com, Parent or Merger Sub, including any amounts required to terminate Stamps.com’s credit facility, contemplated by, and subject to the terms and conditions of, the Merger Agreement. In addition, the proceeds under this debt financing will be used (i) to provide ongoing working capital, and (ii) for other general corporate purposes.

The obligations of the Debt Commitment Parties to provide the debt financing under the Debt Commitment Letter are subject to a number of customary conditions, including, but not limited to (as applicable):

Pursuant to the Guaranty, the Thoma Bravo Fund has agreed to guarantee the due, punctual and complete payment and performance of all of the liabilities and obligations of Parent under the Merger Agreement, including, but not limited to: (1) the aggregate amount of the Parent Termination Fee (as defined under the caption “The Merger—Termination Fee”) solely if and when any of the Parent Termination Fee is payable pursuant to the Merger Agreement; (2) any amounts due by Parent pursuant to legal proceedings as a result of default under the Merger Agreement; and (3) the reimbursement obligations of Parent pursuant to the indemnification obligations to Stamps.com and its representatives in connection with any debt financing. We refer to the obligations set forth in the preceding sentence as the “Guaranteed Obligations.” The obligations of the Thoma Bravo Fund under the Guaranty are subject to a cap equal to $397,000,000.

Subject to specified exceptions, the Guaranty will terminate upon the earliest of:

The closing of the Merger will take place no later than the second business day following the satisfaction or waiver in accordance with the Merger Agreement of all of the conditions to closing of the Merger (as described under the caption, “Proposal 1: Adoption of the Merger Agreement— Conditions to the Closing of the Merger”), other than conditions that by their terms are to be satisfied at the closing but subject to the satisfaction or waiver of such conditions, or such other time agreed to in writing by Parent, Stamps.com and Merger Sub.

If the Merger is consummated, stockholders who continuously hold shares of Stamps.com common stock through the Effective Time, who do not vote in favor of the adoption of the Merger Agreement and who properly demand appraisal of their shares and who do not withdraw or waive their demands or otherwise lose their rights of appraisal will be entitled to seek appraisal of their shares in connection with the Merger under Section 262. The following discussion is not a complete statement of the law pertaining to appraisal rights under the DGCL and is qualified in its entirety by the full text of Section 262, which is attached to this proxy statement as Annex C and incorporated herein by reference. The following summary does not constitute any legal or other advice and does not constitute a recommendation that stockholders exercise their appraisal rights under Section 262. All references in Section 262 and in this summary to a “stockholder” are to the record holder of shares of Stamps.com common stock unless otherwise expressly noted herein. Only a holder of record of shares of Stamps.com common stock is entitled to demand appraisal of the shares registered in that holder’s name. A person having a beneficial interest in shares of Stamps.com common stock held of record in the name of another person, such as a bank, broker, trust or other nominee, must act promptly to cause the record holder to follow the steps summarized below properly and in a timely manner to perfect appraisal rights. If you hold your shares of Stamps.com common stock through a bank, broker or other nominee and you wish to exercise appraisal rights, you should consult with your bank, broker or the other nominee.

Under Section 262, if the Merger is completed, holders of shares of Stamps.com common stock who: (1) submit a written demand for appraisal of their shares prior to the vote to adopt the Merger Agreement at the Special Meeting, (2) do not vote in favor of the adoption of the Merger Agreement; (3) continuously are the record holders of such shares through the Effective Time; and (4) otherwise exactly follow the procedures set forth in Section 262 may be entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash of the “fair value” of the shares of Stamps.com common stock, exclusive of any element of value arising from the accomplishment or expectation of the Merger, together with interest to be paid on the amount determined to be fair value, if any, as determined by the court. However, after an appraisal petition has been filed, the Delaware Court of Chancery will dismiss appraisal proceedings as to all stockholders who have asserted appraisal rights unless (a) the

total number of shares entitled to appraisal exceeds 1% of the outstanding shares of Stamps.com common stock as measured in accordance with subsection (g) of Section 262; or (b) the value of the aggregate Per Share Price in respect of such shares exceeds $1 million (conditions (a) and (b) referred to as the “ownership thresholds”). Unless the Delaware Court of Chancery, in its discretion, determines otherwise for good cause shown, interest on an appraisal award will accrue and compound quarterly from the Effective Time through the date the judgment is paid at 5% over the Federal Reserve discount rate (including any surcharge) as established from time to time during such period. However, at any time before the Delaware Court of Chancery enters judgment in the appraisal proceedings, the Surviving Corporation may voluntarily pay to each stockholder entitled to appraisal an amount in cash pursuant to subsection (h) of Section 262, in which case such interest will accrue after the time of such payment only on an amount that equals the difference, if any, between the amount so paid and the “fair value” of the shares as determined by the Delaware Court of Chancery, in addition to any interest accrued prior to the time of such voluntary cash payment, unless paid at such time. The Surviving Corporation is under no obligation to make such voluntary cash payment prior to such entry of judgment.

Under Section 262, where a Merger Agreement is to be submitted for adoption at a meeting of stockholders, the corporation, not less than 20 days prior to the meeting, must notify each of its stockholders who was such on the record date for notice of such meeting with respect to shares for which appraisal rights are available that appraisal rights are available and include in the notice a copy of Section 262. This proxy statement constitutes Stamps.com’s notice to stockholders that appraisal rights are available in connection with the Merger, and the full text of Section 262 is attached to this proxy statement as Annex C. In connection with the Merger, any holder of shares of Stamps.com common stock who wishes to exercise appraisal rights, or who wishes to preserve such holder’s right to do so, should review Annex C carefully. Failure to strictly comply with the requirements of Section 262 in a timely and proper manner may result in the loss of appraisal rights under the DGCL. A stockholder who loses his, her or its appraisal rights will be entitled to receive the Per Share Price described in the Merger Agreement. Moreover, because of the complexity of the procedures for exercising the right to seek appraisal of shares of Stamps.com common stock, Stamps.com believes that if a stockholder considers exercising such rights, that stockholder should seek the advice of legal counsel.

Stockholders wishing to exercise the right to seek an appraisal of their shares of Stamps.com common stock must do ALL of the following:

In addition:

Because a proxy that does not contain voting instructions will, unless revoked, be voted in favor of the adoption of the Merger Agreement, a stockholder who votes by proxy and who wishes to exercise appraisal rights must vote against the adoption of the Merger Agreement or abstain.

Any holder of shares of Stamps.com common stock wishing to exercise appraisal rights must deliver to Stamps.com, before the vote on the adoption of the Merger Agreement at the Special Meeting at which the proposal to adopt the Merger Agreement will be submitted to stockholders, a written demand for the appraisal of the stockholder’s shares, and that stockholder must not vote or submit a proxy in favor of the adoption of the Merger Agreement. A holder of shares of Stamps.com common stock exercising appraisal rights must hold of record the shares on the date the written

demand for appraisal is made and must continue to hold the shares of record through the Effective Time. A proxy that is submitted and does not contain voting instructions will, unless revoked, be voted in favor of the adoption of the Merger Agreement, and it will constitute a waiver of the stockholder’s right of appraisal and will nullify any previously delivered written demand for appraisal. Therefore, a stockholder who submits a proxy and who wishes to exercise appraisal rights must submit a proxy containing instructions to vote against the adoption of the Merger Agreement or abstain from voting on the adoption of the Merger Agreement. Neither voting against the adoption of the Merger Agreement nor abstaining from voting or failing to vote on the proposal to adopt the Merger Agreement will, in and of itself, constitute a written demand for appraisal satisfying the requirements of Section 262. The written demand for appraisal must be in addition to and separate from any proxy or vote on the adoption of the Merger Agreement. A proxy or vote against the adoption of the Merger Agreement will not constitute a demand. A stockholder’s failure to make the written demand prior to the taking of the vote on the adoption of the Merger Agreement at the Special Meeting of Stamps.com stockholders will constitute a waiver of appraisal rights.

Only a holder of record of shares of Stamps.com common stock is entitled to demand appraisal rights for the shares registered in that holder’s name. A demand for appraisal in respect of shares of Stamps.com common stock must be executed by or on behalf of the holder of record, and must reasonably inform Stamps.com of the identity of the holder and state that the person intends thereby to demand appraisal of the holder’s shares in connection with the Merger. If the shares are owned of record in a fiduciary or representative capacity, such as by a trustee, guardian or custodian, such demand must be executed by or on behalf of the record owner, and if the shares are owned of record by more than one person, as in a joint tenancy and tenancy in common, the demand must be executed by or on behalf of all joint owners. An authorized agent, including an authorized agent for two or more joint owners, may execute a demand for appraisal on behalf of a holder of record; however, the agent must identify the record owner or owners and expressly disclose that, in executing the demand, the agent is acting as agent for the record owner or owners. If a stockholder holds shares of Stamps.com common stock through a broker who in turn holds the shares through a central securities depository nominee such as Cede & Co., a demand for appraisal of such shares must be made by or on behalf of the depository nominee and must identify the depository nominee as record holder.

STOCKHOLDERS WHO HOLD THEIR SHARES IN BROKERAGE OR BANK ACCOUNTS OR OTHER NOMINEE FORMS AND WHO WISH TO EXERCISE APPRAISAL RIGHTS SHOULD CONSULT WITH THEIR BANK, BROKER OR OTHER NOMINEES, AS APPLICABLE, TO DETERMINE THE APPROPRIATE PROCEDURES FOR THE BANK, BROKER OR OTHER NOMINEE TO MAKE A DEMAND FOR APPRAISAL OF THOSE SHARES. A PERSON HAVING A BENEFICIAL INTEREST IN SHARES HELD OF RECORD IN THE NAME OF ANOTHER PERSON, SUCH AS A BANK, BROKER OR OTHER NOMINEE, MUST ACT PROMPTLY TO CAUSE THE RECORD HOLDER TO FOLLOW PROPERLY AND IN A TIMELY MANNER THE STEPS NECESSARY TO PERFECT APPRAISAL RIGHTS.

All written demands for appraisal pursuant to Section 262 should be mailed or delivered to:

Stamps.com Inc.

Attention: Investor Relations

1990 E. Grand Avenue

El Segundo, CA 90245

Any holder of shares of Stamps.com common stock who has delivered a written demand to Stamps.com and who has not commenced an appraisal proceeding or joined that proceeding as a named party may withdraw his, her or its demand for appraisal and accept the consideration offered pursuant to the Merger Agreement by delivering to Stamps.com a written withdrawal of the demand for appraisal. However, any such attempt to withdraw the demand made more than 60 days after the Effective Time will require the consent of the Surviving Corporation. No appraisal proceeding in the Delaware Court of Chancery will be dismissed as to any stockholder without the approval of the Delaware Court of Chancery, and such approval may be conditioned upon such terms as the Delaware Court of Chancery deems just; provided, however, that this shall not affect the right of any stockholder who has not commenced an appraisal proceeding or joined that proceeding as a named party to withdraw such stockholder’s demand for appraisal and to accept the consideration offered pursuant to the Merger Agreement within 60 days after the Effective Time. If no petition for appraisal is filed with the Delaware Court within 120 days after the Effective Time, stockholders' rights to appraisal shall cease, and all holders of shares of Stamps.com common stock will be entitled to receive the consideration offered pursuant to the Merger Agreement. If an appraisal proceeding is commenced and Stamps.com, as the Surviving Corporation, does not approve a request to withdraw a demand for appraisal when that approval is required, or, except with respect to any stockholder who withdraws such stockholder’s

demand in accordance with the proviso in the immediately preceding sentence, if the Delaware Court of Chancery does not approve the dismissal of an appraisal proceeding with respect to a stockholder, the stockholder will be entitled to receive only the appraised value determined in any such appraisal proceeding, which value could be less than, equal to or more than the per share merger consideration being offered pursuant to the Merger Agreement.

If the Merger is completed, within 10 days after the Effective Time, the Surviving Corporation will notify each holder of shares of Stamps.com common stock who has properly made a written demand for appraisal pursuant to Section 262, and who has not voted in favor of the adoption of the Merger Agreement, that the Merger has become effective and the effective date thereof.

Within 120 days after the Effective Time, but not thereafter, the Surviving Corporation or any holder of shares of Stamps.com common stock who has complied with Section 262 and is entitled to seek appraisal under Section 262 (including for this purpose any beneficial owner of the relevant shares) may commence an appraisal proceeding by filing a petition in the Delaware Court of Chancery, with a copy served on the Surviving Corporation in the case of a petition filed by a stockholder (or beneficial owner), demanding a determination of the fair value of the shares held by all dissenting stockholders entitled to appraisal. The Surviving Corporation is under no obligation, and has no present intention, to file a petition, and stockholders should not assume that the Surviving Corporation will file a petition or initiate any negotiations with respect to the fair value of the shares of Stamps.com common stock. Accordingly, any holders of shares of Stamps.com common stock who desire to have their shares appraised should initiate all necessary action to perfect their appraisal rights in respect of their shares of Stamps.com common stock within the time and in the manner prescribed in Section 262. The failure of a holder of Stamps.com common stock to file such a petition within the period specified in Section 262 could nullify the stockholder’s previous written demand for appraisal.

Within 120 days after the Effective Time, any holder of shares of Stamps.com common stock who has complied with the requirements of Section 262 and who is entitled to appraisal rights thereunder will be entitled, upon written request, to receive from the Surviving Corporation a statement setting forth the aggregate number of shares not voted in favor of the adoption of the Merger Agreement and with respect to which Stamps.com has received demands for appraisal, and the aggregate number of holders of such shares. The Surviving Corporation must mail this statement to the requesting stockholder within 10 days after receipt by the Surviving Corporation of the written request for such a statement or within 10 days after the expiration of the period for delivery of demands for appraisal, whichever is later. A beneficial owner of shares of Stamps.com common stock held either in a voting trust or by a nominee on behalf of such person may, in such person’s own name, file a petition seeking appraisal or request from the Surviving Corporation the foregoing statements. As noted above, however, the demand for appraisal can only be made by a stockholder of record.

If a petition for an appraisal is duly filed by a holder of shares of Stamps.com common stock and a copy thereof is served upon the Surviving Corporation, the Surviving Corporation will then be obligated within 20 days after such service to file with the Delaware Register in Chancery a duly verified list containing the names and addresses of all stockholders who have demanded payment for their shares and with whom agreements as to the value of their shares have not been reached. Upon the filing of any such petition, the Delaware Court of Chancery may order that notice of the time and place fixed for the hearing on the petition be mailed to the Surviving Corporation and all of the stockholders shown on such list at the addresses stated therein. Such notice will also be published at least one week before the day of the hearing in a newspaper of general circulation published in the City of Wilmington, Delaware, or in another publication determined by the court. The costs of these notices are borne by the Surviving Corporation. After notice to stockholders as required by the court, the Delaware Court of Chancery is empowered to conduct a hearing on the petition to determine those stockholders who have complied with Section 262 and who have become entitled to appraisal rights thereunder. The Delaware Court of Chancery may require the stockholders who demanded payment for their shares to submit their stock certificates (if any) to the Register in Chancery for notation thereon of the pendency of the appraisal proceedings and, if any stockholder fails to comply with the direction, the Delaware Court of Chancery may dismiss that stockholder from the proceedings. The Delaware Court of Chancery will dismiss appraisal proceedings as to all stockholders who have asserted appraisal rights if neither of the ownership thresholds is met.

After determining the holders of Stamps.com common stock entitled to appraisal and that at least one of the ownership thresholds described above has been satisfied as to stockholders seeking appraisal rights, the appraisal proceeding will be conducted in accordance with the rules of the Delaware Court of Chancery, including any rules specifically governing appraisal proceedings. Through such proceeding, the Delaware Court of Chancery will determine the “fair value” of the shares of Stamps.com common stock, exclusive of any element of value arising from the accomplishment or expectation of the Merger, together with interest, if any, to be paid upon the amount determined to be the fair value. In determining fair value, the Delaware Court of Chancery will take into account all relevant factors. Unless the court in its discretion determines otherwise for good cause shown, interest from the Effective Time through the date of payment of the judgment will be compounded quarterly and will accrue at 5% over the Federal Reserve discount rate (including any surcharge) as established from time to time during the period between the Effective Time and the date of payment of the judgment. However, at any time before the Delaware Court of Chancery enters judgment in the appraisal proceedings, the Surviving Corporation may pay to each stockholder entitled to appraisal an amount in cash, in which case such interest will accrue after the time of such payment only on an amount that equals the difference, if any, between the amount so paid and the “fair value” of the shares as determined by the Delaware Court of Chancery, in addition to any interest accrued prior to the time of such voluntary payment, unless paid at such time.

In Weinberger v. UOP, Inc., the Supreme Court of Delaware discussed the factors that could be considered in determining fair value in an appraisal proceeding, stating that “proof of value by any techniques or methods which are generally considered acceptable in the financial community and otherwise admissible in court” should be considered, and that “[f]air price obviously requires consideration of all relevant factors involving the value of a company.” The Delaware Supreme Court stated that, in making this determination of fair value, the court must consider market value, asset value, dividends, earnings prospects, the nature of the enterprise and any other facts that could be ascertained as of the date of the Merger that throw any light on future prospects of the merged corporation. Section 262 provides that fair value is to be “exclusive of any element of value arising from the accomplishment or expectation of the Merger.” In Cede & Co. v. Technicolor, Inc., the Delaware Supreme Court stated that such exclusion is a “narrow exclusion [that] does not encompass known elements of value,” but which rather applies only to the speculative elements of value arising from such accomplishment or expectation. In Weinberger, the Supreme Court of Delaware also stated that “elements of future value, including the nature of the enterprise, which are known or susceptible of proof as of the date of the Merger and not the product of speculation, may be considered.”

Stockholders considering seeking appraisal should be aware that the fair value of their shares as so determined by the Delaware Court of Chancery could be more than, the same as or less than the consideration they would receive pursuant to the Merger if they did not seek appraisal of their shares and that an opinion of an investment banking firm as to the fairness from a financial point of view of the consideration payable in a Merger is not an opinion as to, and does not in any manner address, fair value under Section 262. No representation is made as to the outcome of the appraisal of fair value as determined by the Delaware Court of Chancery, and stockholders should recognize that such an appraisal could result in a determination of a value higher or lower than, or the same as, the Per Share Price. Neither Stamps.com nor Parent anticipates offering more than the Per Share Price to any stockholder exercising appraisal rights, and each of Stamps.com and Parent reserves the rights to make a voluntary cash payment pursuant to subsection (h) of Section 262 and to assert, in any appraisal proceeding, that for purposes of Section 262, the “fair value” of a share of Stamps.com common stock is less than the Per Share Price. If a petition for appraisal is not timely filed, or if neither of the ownership thresholds described above has been satisfied as to stockholders seeking appraisal rights, then the right to an appraisal will cease. The costs of the appraisal proceedings (which do not include attorneys’ fees or the fees and expenses of experts) may be determined by the Delaware Court of Chancery and taxed upon the parties as the Delaware Court of Chancery deems equitable under the circumstances. Upon application of a stockholder, the Delaware Court of Chancery may also order that all or a portion of the expenses incurred by a stockholder in connection with an appraisal proceeding, including, without limitation, reasonable attorneys’ fees and the fees and expenses of experts, be charged pro rata against the value of all the shares entitled to be appraised. In the absence of such determination or assessment, each party bears its own expenses.

If any stockholder who demands appraisal of his, her or its shares of Stamps.com common stock under Section 262 fails to perfect, or effectively loses or withdraws, such holder’s right to appraisal, such stockholder will be entitled to receive only the consideration offered pursuant to the Merger Agreement. A stockholder will fail to perfect, or effectively lose or withdraw, the holder’s right to appraisal if no petition for appraisal is filed within 120 days after the Effective Time, if neither of the ownership thresholds described above has been satisfied as to stockholders

seeking appraisal rights or if the stockholder delivers to the Surviving Corporation a written withdrawal of the holder’s demand for appraisal and an acceptance of the Per Share Price in accordance with Section 262.

From and after the Effective Time, no stockholder who has demanded appraisal rights will be entitled to vote such shares of Stamps.com common stock for any purpose or to receive payment of dividends or other distributions on the stock, except dividends or other distributions on the holder’s shares of Stamps.com common stock, if any, payable to stockholders as of a time prior to the Effective Time. If no petition for an appraisal is filed, if neither of the ownership thresholds described above has been satisfied as to the stockholders seeking appraisal rights, or if the stockholder delivers to the Surviving Corporation a written withdrawal of the demand for an appraisal and an acceptance of the Merger, either within 60 days after the Effective Time or thereafter with the written approval of the Surviving Corporation, then the right of such stockholder to an appraisal will cease. Once a petition for appraisal is filed with the Delaware Court of Chancery, however, the appraisal proceeding may not be dismissed as to any stockholder without the approval of the court, and such approval may be conditioned upon such terms as the court deems just; provided, however, that the foregoing shall not affect the right of any stockholder who has not commenced an appraisal proceeding or joined that proceeding as a named party to withdraw such stockholder’s demand for appraisal and to accept the terms offered upon the Merger within 60 days after the Effective Time.

Failure to comply strictly with all of the procedures set forth in Section 262 may result in the loss of a stockholder’s statutory appraisal rights. Consequently, any stockholder wishing to exercise appraisal rights is encouraged to consult legal counsel before attempting to exercise those rights.

Between August 23 and August 27, 2021, three lawsuits have been filed in the United States District Court for the Southern District of New York against Stamps.com and its directors: Stein v. Stamps.com Inc. et al., 1:21-cv-7108 (S.D.N.Y.); Hejazi v. Stamps.com Inc. et al., 1:21-cv-07227 (S.D.N.Y.); and Ciccotelli v. Stamps.com Inc. et al., 1:21-cv-07246 (S.D.N.Y.). The complaints name Stamps.com and the Stamps.com directors as defendants. The complaints each allege that the Preliminary Proxy Statement filed on August 19, 2021 relating to the Merger omitted material information that rendered it false and misleading. As a result of the alleged omissions, the lawsuits seek to hold Stamps.com and its directors liable for violating Section 14(a) of the Exchange Act and Rule 14a-9 promulgated thereunder, and additionally seeks to hold Stamps.com’s directors liable as control persons pursuant to Section 20(a) of the Exchange Act.

Stamps.com has not yet responded to the complaints filed in any of the above lawsuits. Each complaint seeks, among other relief, an injunction preventing the closing of the merger, rescission of the merger agreement or any of its terms to the extent already implemented or awarding of rescissory damages, damages, and an award of attorneys’ and experts’ fees. While Stamps.com believes the complaints are without merit, there can be no assurance that it will ultimately prevail in any or all such lawsuits. Additionally, additional lawsuits may be filed before the stockholder meeting and/or the consummation of the Merger.

The Merger will be accounted for as a “purchase transaction” for financial accounting purposes.

The following discussion is a summary of material U.S. federal income tax consequences of the Merger that may be relevant to U.S. Holders and Non-U.S. Holders (each as defined below) of shares of Stamps.com common stock whose shares are converted into the right to receive cash pursuant to the Merger. This summary does not describe any tax consequences arising under the laws of any state, local or non-U.S. jurisdiction and does not consider any aspects of U.S. federal tax law other than income taxation. This discussion is based upon the Internal Revenue Code of 1986, as amended (the “Code”), Treasury Regulations promulgated under the Code, court decisions, published positions of the Internal Revenue Service (the “IRS”), and other applicable authorities, all as in effect on the date of this proxy statement and all of which are subject to change or differing interpretations at any time, possibly with retroactive effect. This discussion is limited to Stamps.com stockholders who hold their shares of Stamps.com common stock as “capital assets” within the meaning of Section 1221 of the Code (generally, property held for investment purposes).

This discussion is for general information only and does not address all of the tax consequences that may be relevant to Stamps.com stockholders in light of their particular circumstances. For example, this discussion does not address:

We have not sought, and do not intend to seek, any ruling from the IRS with respect to the statements made and the conclusions reached in the following summary, and no assurance can be given that the IRS will agree with the views expressed herein, or that a court will not sustain any challenge by the IRS in the event of litigation.

THE FOLLOWING SUMMARY IS FOR GENERAL INFORMATIONAL PURPOSES ONLY AND IS NOT A SUBSTITUTE FOR CAREFUL TAX PLANNING AND ADVICE. WE URGE YOU TO CONSULT YOUR OWN TAX ADVISOR WITH RESPECT TO THE SPECIFIC TAX CONSEQUENCES TO YOU IN CONNECTION WITH THE MERGER IN LIGHT OF YOUR OWN PARTICULAR CIRCUMSTANCES, INCLUDING FEDERAL ESTATE, GIFT AND OTHER NON-INCOME TAX CONSEQUENCES, AND TAX CONSEQUENCES UNDER STATE, LOCAL OR NON-U.S. TAX LAWS.

For purposes of this discussion, a “U.S. Holder” is a beneficial owner of shares of Stamps.com common stock that is for U.S. federal income tax purposes:

The receipt of cash by a U.S. Holder in exchange for shares of Stamps.com common stock pursuant to the Merger will be a taxable transaction for U.S. federal income tax purposes. In general, such U.S. Holder’s gain or loss will be equal to the difference, if any, between the amount of cash received and the U.S. Holder’s adjusted tax basis in the shares of Stamps.com common stock surrendered pursuant to the Merger. Gain or loss must be determined separately for each block of shares (that is, shares of Stamps.com common stock acquired at the same cost in a single transaction). A U.S. Holder’s adjusted tax basis generally will equal the amount that such U.S. Holder paid for the shares of Stamps.com common stock. A U.S. Holder’s gain or loss on the disposition of shares of Stamps.com common stock will generally be characterized as capital gain or loss. Any such gain or loss will be long-term capital gain or loss if such U.S. Holder’s holding period in such shares is more than one year at the time of the completion of the Merger. A reduced tax rate on capital gain generally will apply to long-term capital gain of a non-corporate U.S. Holder (including individuals). The deductibility of capital losses is subject to limitations.

The following is a summary of the material U.S. federal income tax consequences that will apply to you if you are a Non-U.S. Holder. The term “Non-U.S. Holder” means a beneficial owner of Stamps.com common stock that is, for U.S. federal income tax purposes, not a U.S. Holder.

Any gain realized by a Non-U.S. Holder pursuant to the Merger generally will not be subject to U.S. federal income tax unless:

Information reporting and backup withholding (currently, at a rate of 24%) may apply to the proceeds received by a Stamps.com stockholder pursuant to the Merger. Backup withholding generally will not apply to (1) a U.S. Holder that furnishes a correct taxpayer identification number and certifies that such holder is not subject to backup withholding on IRS Form W-9 (or a substitute or successor form) or (2) a Non-U.S. Holder that (i) provides a certification of such holder’s foreign status on the appropriate series of IRS Form W-8 (or a substitute or successor form) or (ii) otherwise establishes an exemption from backup withholding. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules will be allowed as a refund or a credit against the holder’s U.S. federal income tax liability, provided that the required information is timely furnished to the IRS.

Sections 1471 through 1474 of the Code (“FATCA”), impose a U.S. federal withholding tax of 30% on certain payments made to a “foreign financial institution” (as specially defined under these rules) unless such institution enters into an agreement with the U.S. government to withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding certain U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners) or an exemption applies. FATCA also generally will impose a U.S. federal withholding tax of 30% on certain payments made to a non-financial foreign entity unless such entity provides the withholding agent a certification identifying certain direct and indirect U.S. owners of the entity or an exemption applies. An intergovernmental agreement between the United States and an applicable foreign country may modify these requirements. Under certain circumstances, a Non-U.S. Holder might be eligible for refunds or credits of such taxes. Although the Code provides that FATCA withholding generally also will apply to payments of gross proceeds from sales or other dispositions of Stamps.com common stock, the U.S. Treasury Department released proposed regulations which, if finalized in their present form, would eliminate the federal withholding tax of 30% applicable to such gross proceeds. In its preamble to such proposed regulations, the U.S. Treasury Department stated that taxpayers may generally rely on the proposed regulations until final regulations are issued.

You are encouraged to consult with your own tax advisors regarding the possible implications of FATCA on the disposition of Stamps.com common stock pursuant to the Merger.

You are urged to consult your tax advisor with respect to the application of U.S. federal income tax laws to your particular circumstances as well as any tax consequences arising under the U.S. federal estate or gift tax rules, or under the laws of any state, local or foreign tax laws.

Stamps.com and Parent have agreed to take all action necessary to comply with all regulatory notification requirements, and, subject to certain limitations, to obtain all regulatory approvals required to consummate the Merger and the other transactions contemplated by the Merger Agreement. These approvals include approval under the HSR Act and any other applicable antitrust laws (whether domestic or foreign).

Under the HSR Act and the Austrian Cartel Act, and the rules promulgated thereunder, certain acquisitions may not be completed until information has been furnished to the Antitrust Division of the U.S. Department of Justice (“DOJ”) and the Federal Trade Commission (“FTC”), the applicable waiting periods for the HSR Act and Federal Cartel Authority and the Federal Cartel Attorney Competition Authority have expired or been terminated, and in the case of an application to the Cartel Court, clearance obtained or the application for an in-depth review rejected or withdrawn. The waiting periods under the HSR Act and Austrian Cartel Act are 30 calendar days for the HSR Act unless the waiting period is terminated earlier or extended by a request for additional information and documentary material, and four calendar weeks from the date of notification of the merger filing in Austria for the Austrian Cartel Act, The Merger is subject to the provisions of the HSR Act and the Austrian Cartel Act, and therefore cannot be completed until Stamps.com and Parent file a notification and report form with the FTC and the DOJ under the HSR Act and Thoma Bravo files a merger filing notification with the Austrian Cartel Act and the applicable waiting period has expired or been terminated in the U.S., and the Austrian competition authority has issued a clearance decision in Austria. Stamps.com and Thoma Bravo Fund made the necessary filings with the FTC and the Antitrust Division

of the DOJ on July 21, 2021, and the waiting period has expired. The Austrian filing was made on July 29, 2021, and declaratory clearance confirmation has been received under the Austrian Cartel Act. Stamps.com and Thoma Bravo Fund may also file pre-merger or post-merger notification filings, forms and submissions with other Governmental Authorities (as defined in the Merger Agreement) pursuant to other applicable antitrust laws in connection with the Merger to the extent required in the reasonable judgement of counsel to Parent and Stamps.com. The Merger Agreement provides that Stamps.com, Parent and Merger Sub will use reasonable best efforts to obtain regulatory clearance, including, to the extent necessary to obtain clearance of the Merger pursuant to the HSR Act and any other antitrust laws applicable to the Merger; provided, however, that no party is required to (x) offer, commit to or effect, by consent decree, hold separate order or otherwise, the sale, divestiture, license or other disposition of any capital stock or other equity or voting interest, assets (whether tangible or intangible), rights, products or businesses of any person, or any other restrictions on the activities of any Person; or (y) contest, defend or appeal any Legal Proceedings (as defined in the Merger Agreement).

At any time before or after consummation of the Merger, notwithstanding the termination or expiration of the waiting periods under the HSR Act, the FTC or the DOJ could take such action under the antitrust laws as it deems necessary or desirable in the public interest, including seeking to enjoin the completion of the Merger, seeking divestiture of substantial assets of the parties, or requiring the parties to license or hold separate assets or terminate existing relationships and contractual rights. At any time before or after the completion of the Merger, any state or foreign jurisdiction could take such action under the antitrust laws as it deems necessary or desirable in the public interest. Such action could include seeking to enjoin the completion of the Merger or seeking divestiture of substantial assets of the parties. Private parties may also seek to take legal action under the antitrust laws under certain circumstances. We cannot be certain that a challenge to the Merger will not be made or that, if a challenge is made, we will prevail.

One or more governmental agencies may impose a condition, restriction, qualification, requirement or limitation when it grants the necessary approvals and consents. Third parties may also seek to intervene in the regulatory process or litigate to enjoin or overturn regulatory approvals, any of which actions could significantly impede or even preclude obtaining required regulatory approvals. There is currently no way to predict how long it will take to obtain all of the required regulatory approvals or whether such approvals will ultimately be obtained and there may be a substantial period of time between the approval by stockholders and the completion of the Merger.

Although we expect that all required regulatory clearances and approvals will be obtained, we cannot assure you that these regulatory clearances and approvals will be timely obtained, obtained at all or that the granting of these regulatory clearances and approvals will not involve the imposition of additional conditions on the completion of the Merger, including the requirement to divest assets, or require changes to the terms of the Merger Agreement. These conditions or changes could result in the conditions to the Merger not being satisfied.

The following summary describes the material provisions of the Merger Agreement. The descriptions of the Merger Agreement in this summary and elsewhere in this proxy statement are not complete and are qualified in their entirety by reference to the Merger Agreement, a copy of which is attached to this proxy statement as Annex A and incorporated into this proxy statement by reference. You should carefully read and consider the entire Merger Agreement, which is the legal document that governs the Merger, because this summary may not contain all the information about the Merger Agreement that is important to you. The rights and obligations of the parties are governed by the express terms of the Merger Agreement and not by this summary or any other information contained in this proxy statement.

The representations, warranties, covenants and agreements described below and included in the Merger Agreement (1) were made only for purposes of the Merger Agreement and as of specific dates; (2) were made solely for the benefit of the parties to the Merger Agreement; and (3) may be subject to important qualifications, limitations and supplemental information agreed to by Stamps.com, Parent and Merger Sub in connection with negotiating the terms of the Merger Agreement. In addition, the representations and warranties have been included in the Merger Agreement for the purpose of allocating contractual risk between Stamps.com, Parent and Merger Sub rather than to establish matters as facts, and may be subject to standards of materiality applicable to such parties that differ from those applicable to investors. Stockholders are not third party beneficiaries under the Merger Agreement and should not rely on the representations, warranties, covenants and agreements or any descriptions thereof as characterizations of the actual state of facts or condition of Stamps.com, Parent or Merger Sub or any of their respective affiliates or businesses. Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Merger Agreement. In addition, you should not rely on the covenants in the Merger Agreement as actual limitations on the respective businesses of Stamps.com, Parent and Merger Sub, because the parties may take certain actions that are either expressly permitted in the confidential disclosure letter to the Merger Agreement or as otherwise consented to by the appropriate party, which consent may be given without prior notice to the public. The Merger Agreement is described below, and included as Annex A, only to provide you with information regarding its terms and conditions, and not to provide any other factual information regarding Stamps.com, Parent, Merger Sub or their respective businesses. Accordingly, the representations, warranties, covenants and other agreements in the Merger Agreement should not be read alone, and you should read the information provided elsewhere in this document and in our filings with the SEC regarding Stamps.com and our business.

The Merger Agreement provides that, subject to the terms and conditions of the Merger Agreement, and in accordance with the DGCL, at the Effective Time: (1) Merger Sub will be merged with and into Stamps.com, with Stamps.com becoming a wholly owned subsidiary of Parent; and (2) the separate corporate existence of Merger Sub will thereupon cease. From and after the Effective Time, the Surviving Corporation will possess all properties, rights, privileges, powers and franchises of Stamps.com and Merger Sub, and all of the debts, liabilities and duties of Stamps.com and Merger Sub will become the debts, liabilities and duties of the Surviving Corporation.

At the Effective Time, the board of directors of the Surviving Corporation will consist of the directors of Merger Sub as of immediately prior to the Effective Time, to hold office in accordance with the certificate of incorporation and bylaws of the Surviving Corporation until their successors are duly elected or appointed and qualified. At the Effective Time, the officers of Stamps.com as of immediately prior to the Effective Time will be the officers of the Surviving Corporation, until their successors are duly appointed. At the Effective Time, the certificate of incorporation of Stamps.com as the Surviving Corporation will be amended to read substantially identically to the certificate of incorporation of Merger Sub as in effect immediately prior to the Effective Time, and the bylaws of Merger Sub, as in effect immediately prior to the Effective Time, will become the bylaws of the Surviving Corporation, until thereafter amended.

The closing of the Merger will take place no later than the second business day following the satisfaction or waiver of all conditions to closing of the Merger (described below under the caption, “—Conditions to the Closing of the Merger”) (other than those conditions to be satisfied at the closing of the Merger) or such other time agreed to in writing by Parent, Stamps.com and Merger Sub. On the Closing Date (as defined in the Merger Agreement), the

parties will file a certificate of merger with the Secretary of State of the State of Delaware as provided under the DGCL. The Effective Time of the Merger will occur upon the filing of a certificate of merger with the Secretary of State of the State of Delaware in accordance with the applicable provision of the DGCL.

At the Effective Time, and without any action required by any stockholder, each share of Stamps.com common stock (other than Owned Company Shares or Dissenting Company Shares, which include, for example, shares of Stamps.com common stock owned by stockholders who have properly and validly exercised their statutory rights of appraisal under Section 262) outstanding as of immediately prior to the Effective Time will be cancelled and extinguished, and automatically converted into the right to receive the Per Share Price, less any applicable withholding of taxes.

Each Company Option (whether vested or unvested) that is outstanding as of immediately prior to the Effective Time shall accelerate and become fully vested and exercisable effective immediately prior to, and contingent upon, the Effective Time and shall be cancelled and automatically converted into the right to receive an amount in cash, without interest, equal to the product of (A) the aggregate number of shares of Stamps.com common stock subject to such Company Option, multiplied by (B) the excess, if any, of the Per Share Price over the applicable per share exercise price under such Company Option, subject to any required withholding of taxes.

Any Company Option that is unexpired, unexercised, and outstanding as of immediately prior to the Effective Time with a per share exercise price equal to or greater than $330.00 will be cancelled immediately upon the Effective Time without payment or consideration.

Each Company RSU Award (whether vested or unvested) that is outstanding as of immediately prior to the Effective Time shall accelerate and become fully vested effective immediately prior to, and contingent upon, the Effective Time, and shall be cancelled and automatically converted into the right to receive an amount in cash, without interest, equal to the product of (A) the aggregate number of shares of Stamps.com common stock subject to the Company RSU Award multiplied by (B) the Per Share Price, subject to any required withholding of taxes.

The Company Equity Plans will terminate as of the Effective Time and the provisions in any other employee plan or contract providing for the issuance or grant of any other interest in respect of the capital stock of Stamps.com will be cancelled as of the Effective Time.

The Merger Agreement generally provides that no new offering periods or purchase periods will begin under the ESPP after July 8, 2021, no new participants will be allowed to begin participating in the ESPP after July 8, 2021 or as soon as administratively practicable thereafter, and no new Purchase Interval (as defined in the ESPP) will commence or be extended pursuant to the ESPP, in each case, after July 8, 2021. After July 8, 2021, except to the extent necessary to maintain the status of the ESPP as an “employee stock purchase plan” within the meaning of Section 423 of the Code and the Treasury Regulations thereunder, each ESPP participant will not be allowed to increase his or her payroll contribution rate from the rate in effect as of July 8, 2021, or make separate non-payroll contributions to the ESPP, except as required by applicable law. Each share of Stamps.com common stock purchased under the ESPP that remains outstanding as of immediately before the Effective Time shall be cancelled at the Effective Time and converted into the right to receive the Per Share Price less any applicable withholding taxes.

Prior to the Closing, Parent will designate Stamps.com’s transfer agent or such other bank or trust company, reasonably acceptable to Stamps.com (the “Payment Agent”) to act as the payment agent for the Merger. At or prior to the Closing, Parent will deposit (or cause to be deposited) with the Payment Agent cash sufficient to pay the aggregate consideration to Stamps.com’s stockholders.

Promptly following the Effective Time (and in any event within five business days), the Payment Agent will mail to each holder of record (as of immediately prior to the Effective Time) of (i) a certificate or certificates that

immediately prior to the Effective Time represented outstanding shares of Stamps.com common stock (other than Dissenting Company Shares and Owned Company Shares) (collectively, the “Certificates”); and (ii) uncertificated shares of Stamps.com common stock that represented outstanding shares of Stamps.com common stock (other than Dissenting Company Shares and Owned Company Shares) (collectively, the “Uncertificated Shares”) a letter of transmittal in customary form (or effective affidavits of loss in lieu of such Certificates) and instructions for use in effecting the surrender of such holder’s shares of Stamps.com common stock represented by such holder’s Certificate(s) or Uncertificated Shares in exchange for the Per Share Price payable in respect of such shares. The amount of any Per Share Price paid to stockholders may be reduced by any applicable withholding of taxes.

If any cash deposited with the Payment Agent is not claimed within one year following the Effective Time, such cash will be returned to Parent upon demand, and any holders of Stamps.com common stock who have not complied with the exchange procedures in the Merger Agreement will thereafter look only to Parent as general creditor for payment of the Per Share Price. To the extent permitted by applicable laws, any cash deposited with the Payment Agent that remains unclaimed two years following the Effective Time, or at such earlier date as is immediately prior to the time at which such amounts would otherwise escheat to or become property of any governmental authority, will become the property of the Surviving Corporation free and clear of any claims or interest of any person previously entitled thereto.

The Merger Agreement contains representations and warranties of Stamps.com, Parent and Merger Sub.

Some of the representations and warranties in the Merger Agreement made by Stamps.com are qualified as to “materiality” or “Company Material Adverse Effect.” For purposes of the Merger Agreement, “Company Material Adverse Effect” means any change, event, violation, effect, occurrence, development, circumstance or other matter (each, an “Effect”) that (x) had, individually or in the aggregate, a material adverse effect on the business, assets or financial condition of the Company Group, taken as a whole, or (y) would reasonably be expected to prevent, materially impair or materially delay the consummation by Stamps.com of the Merger prior to the Termination Date, except that, solely with respect to clause (x), none of the following, or any Effects related thereto or arising therefrom, shall be deemed in and of themselves (and subject to the limitations expressly set forth below with respect thereto), either alone or in combination, to constitute, and none of the following shall be taken into account in determining whether there is, or would reasonably be expected to have, a Company Material Adverse Effect on the Company Group:

In the Merger Agreement, Stamps.com has made customary representations and warranties to Parent and Merger Sub that are subject, in some cases, to specified exceptions and qualifications contained in the Merger Agreement. These representations and warranties relate to, among other things:

In the Merger Agreement, Parent and Merger Sub have made customary representations and warranties to Stamps.com that are subject, in some cases, to specified exceptions and qualifications contained in the Merger Agreement. These representations and warranties relate to, among other things:

The representations and warranties contained in the Merger Agreement will not survive the consummation of the Merger.

The Merger Agreement provides that, except as: (1) expressly contemplated by the Merger Agreement; (2) disclosed in the confidential disclosure letter to the Merger Agreement; (3) expressly prohibited by the Merger Agreement; (4) required by applicable law or required, or in Stamps.com’s reasonable, good faith discretion, advisable, in connection with any COVID-19 Measures; or (5) approved in writing in advance by Parent (which approval will not be unreasonably withheld, conditioned or delayed (provided, that Parent shall be deemed to have approved in writing

if it provides no written response within five (5) Business Days after a written request by Stamps.com for such approval)); during the period of time between the date of the signing of the Merger Agreement and the first to occur of the Effective Time and the termination of the Merger Agreement (the “Interim Period”), Stamps.com will and will cause each of its subsidiaries to:

In addition, Stamps.com has also agreed that, except as (1) disclosed in the confidential disclosure letter to the Merger Agreement; (2) approved in writing in advance by Parent (which approval will not be unreasonably withheld, conditioned or delayed (provided, that Parent shall be deemed to have approved in writing if it provides no written response within five (5) Business Days after a written request by Stamps.com for such approval)); (3) to the extent necessary to comply with the express obligations set forth in any Material Contract in effect on the date of the Merger Agreement expressly contemplated by the Merger Agreement; (4) as required by applicable law or required, or in Stamps.com’s reasonable, good faith discretion, advisable in connection with any COVID-19 Measures; or (5) expressly contemplated by the Merger Agreement during the Interim Period, Stamps.com will not, among other things

Under the Merger Agreement, from the date of the Merger Agreement until the No-Shop Period Start Date, Stamps.com and its representatives have the right to, directly or indirectly, among other things: (1) solicit, initiate, propose or induce or knowingly encourage, facilitate or assist any inquiries regarding any proposal or inquiry that constitutes, could constitute or could reasonably be expected to lead to, an Acquisition Proposal (as defined below),

(2) continue, enter into, maintain, participate or otherwise engage in discussions with any third person (and its representatives and financing sources) with respect to any proposal or inquiry that constitutes, could constitute or could reasonably be expected to lead to, an Acquisition Proposal and cooperate with, assist or participate in, or facilitate in any way, such proposals or inquiries or any effort or attempt to make any proposal or inquiry that constitutes, could constitute or could reasonably be expected to lead to, an Acquisition Proposal, or (3) subject to entering into and solely in accordance with an Acceptable Confidentiality Agreement (as defined below), furnish to any third person (and its representatives, prospective debt and equity financing sources and their respective representatives) any information (including nonpublic information and data) relating to the Company Group or afford to any such third person (and its representatives, prospective debt and equity financing sources and their respective representatives) access to the business, properties, assets, books, records or other non-public information and data, or to any personnel, of the Company Group, in any such case with the intent to induce the making, submission or announcement of, or to knowingly encourage, facilitate or assist, any proposal or inquiry that constitutes, or could reasonably be expected to lead to, an Acquisition Proposal or any inquiries or the making of any proposal or inquiry that could constitute or could reasonably be expected to lead to an Acquisition Proposal, provided that Stamps.com must, within 24 hours, provide to Parent, or provide Parent access to, any such non-public information that has not been previously provided to Parent or its representatives, and the Company Group must not provide any competitively sensitive non-public information except in accordance with customary “clean room” or other similar procedures; and Stamps.com may grant a waiver, amendment or release under any “standstill provision” or similar obligation to allow such third person to submit or amend an Acquisition Proposal on a confidential basis to the Board of Directors.

Stamps.com is not entitled to terminate the Merger Agreement for the purpose of entering into an agreement in respect of a Superior Proposal (as defined below), unless it complies with certain procedures in the Merger Agreement, including, but not limited to, providing at least two (2) Business Days prior written notice to Parent and negotiating with Parent in good faith in an effort to amend the terms and conditions of the Merger Agreement, so that such Acquisition Proposal no longer constitutes a Superior Proposal relative to the transactions contemplated by the Merger Agreement, as amended pursuant to such negotiations.

If Stamps.com terminates the Merger Agreement for the purpose of entering into an agreement with any Excluded Party prior to the No-Shop Period Start Date, then Stamps.com would be required to pay a termination fee of $99,500,000 to Parent. For more information, please see the section of this proxy statement captioned “—The Board of Directors’ Recommendation; Company Board Recommendation Change.”

For purposes of this proxy statement and the Merger Agreement:

“Acceptable Confidentiality Agreement” means a confidentiality agreement with Stamps.com that contains customary provisions requiring the counterparty thereto (and any of its affiliates and representatives named therein) that receive non-public information of or with respect to Stamps.com to keep such information confidential (subject to customary exceptions), provided that with respect to agreements executed and delivered after the Merger Agreement, the provisions contained therein are not materially less favorable, in the aggregate, to Stamps.com than the terms of the confidentiality agreement entered into between Stamps.com and Thoma Bravo (except that such agreement need not contain any “standstill” or similar provision or otherwise prohibit the making of any Acquisition Proposal). A joinder to an Acceptable Confidentiality Agreement pursuant to which a third party agrees to be bound by the confidentiality and use provisions of an Acceptable Confidentiality Agreement is an Acceptable Confidentiality Agreement.

“Acquisition Proposal” means any offer, proposal or indication of interest by a Third Person to engage in an Acquisition Transaction.

“Acquisition Transaction” means any transaction or series of related transactions (other than the Merger) involving:

“Excluded Party” means any Third Person (or if a group, includes any Third Person, so long as such Third Person, together with all other members of such group, if any, who were members of such group or another group that included such Person immediately prior to the No-Shop Period Start Date, represent at least 50% of the equity financing of such group at all times following the No-Shop Period Start Date and prior to the closing of the transactions contemplated by the applicable Acquisition Proposal), (a) who submits a written bona fide Acquisition Proposal to Stamps.com or any of its representatives after the date of the Merger Agreement and prior to the No-Shop Period Start Date, (b) whose Acquisition Proposal is determined by the Board of Directors, in good faith, (after consultation with its outside counsel and its financial advisor) to be, or would reasonably be expected to lead to, a Superior Proposal and (c) who did not submit an Acquisition Proposal in writing to the Company Group, the Board of Directors or their respective representatives within six (6) months prior to the date of the Merger Agreement (it being understood that with respect to a group, each member of such group must meet the criteria set forth in this clause (c) at all times (including following any termination of the Merger Agreement) prior to the closing of the transactions contemplated by the applicable Acquisition Proposal) in order for such group to qualify as an Excluded Party; provided, however, that a Third Person shall immediately cease to be an Excluded Party (and the provisions of the Merger Agreement applicable to Excluded Parties shall cease to apply with respect to such Person) if such Acquisition Proposal is withdrawn by such Third Person (or group, if applicable) after the date of the Merger Agreement; it being understood that a modification of an Acquisition Proposal submitted by a Third Person (or group) shall not be deemed a withdrawal or termination of an Acquisition Proposal by such Third Person (or group).

“Superior Proposal” means any bona fide written Acquisition Proposal for an Acquisition Transaction that is on terms that the Board of Directors (or a committee thereof) determines in its good faith judgment, after consultation with its financial advisor and outside legal counsel, is reasonably likely to be consummated in accordance with its terms, taking into account all legal, regulatory and financing aspects (including certainty of closing) of such Acquisition Proposal and the identity of the person making such Acquisition Proposal and other aspects of the Acquisition Proposal that the Board of Directors (or a committee thereof) deems relevant, and if consummated, would result in a transaction more favorable to Stamps.com’s stockholders (solely in their capacity as such) than the Merger (taking into account (i) any revisions to the Merger Agreement made or proposed in writing by Parent prior to the time of such determination and (ii) all legal, regulatory, financial (including any termination fee amounts and conditions), timing financing and other aspects of such Acquisition Proposal), except that for purposes of the definition of “Superior Proposal”, the references to “20%” in the definition of “Acquisition Transaction” shall be deemed to be references to “80%.”

“Third Person” means any person or “group” (within the meaning of Section 13(d) of the Exchange Act), other than (i) Stamps.com or any of its controlled affiliates or (ii) Parent, Merger Sub, the Thoma Bravo Fund or any of their respective affiliates or any “group” including Parent, Merger Sub, Guarantor or any of their respective affiliates.

From the date of the No-Shop Period Start Date until the earlier to occur of the termination of the Merger Agreement and the Effective Time, Stamps.com has agreed not to, and to cause its subsidiaries and its and their respective representatives not to:

In addition, Stamps.com has agreed to, other than with respect to any Excluded Party which has reaffirmed its Acquisition Proposal to the Board of Directors within 24 hours of the No-Shop Period Start Date, cease and cause to be terminated any discussions or negotiations with any person and its representatives, request the prompt return or destruction of all non-public information concerning the Company Group furnished to any person with whom a confidentiality agreement was entered into in connection with its consideration of making an Acquisition Proposal within the twelve-month period immediately preceding the No-Shop Period Start Date and will (i) cease providing any further information with respect to Stamps.com or any Acquisition Proposal to any such persons or their respective representatives and (ii) terminate all access granted to any such persons or their respective representatives to any physical data room, the virtual data room or any other diligence access to non-public information regarding the Company Group made available in connection with an Acquisition Proposal. Stamps.com will not be required to enforce, and will be permitted to waive, terminate or modify any provision of any standstill or confidentiality agreement that prohibits or purports to prohibit a proposal being made to the Board of Directors, if the Board of Directors has determined in good faith, after consultation with outside counsel, that failure to take such action would be inconsistent with its fiduciary duties under applicable law.

Notwithstanding these restrictions, under certain circumstances, prior to the adoption of the Merger Agreement by Stamps.com stockholders, Stamps.com may, among other things, provide information to, and engage or participate in negotiations or substantive discussions with, a person in respect of a bona fide Acquisition Proposal, and otherwise facilitate such Acquisition Proposal or assist such person (and its representatives, prospective debt and equity financing sources and/or their respective representatives) with such Acquisition Proposal (in each case, if requested by such person) and such Acquisition Proposal was not the result of a material breach of Stamps.com’s obligations, as described in the immediately preceding paragraph (provided that Stamps.com and its representatives may contact any Third Person to clarify any ambiguous terms and conditions of an Acquisition Proposal which are necessary to determine whether the Acquisition Proposal constitutes or is reasonably likely to lead to a Superior Proposal) if (and only if), subject to complying with certain procedures described in the subsequent paragraph, the Board of Directors (or a committee thereof) determines in good faith (after consultation with its financial advisor and its outside legal counsel) that (i) such Acquisition Proposal either constitutes a Superior Proposal or is reasonably likely to lead to a Superior Proposal, and (ii) the failure to act in respect of such Acquisition Proposal would be reasonably likely to be inconsistent with the Board of Director’s fiduciary duties to stockholders under applicable law.

Stamps.com is not entitled to terminate the Merger Agreement after the No-Shop Period Start Date for the purpose of entering into an agreement in respect of a Superior Proposal unless it complies with certain procedures in the Merger Agreement, including, but not limited to, providing prior written notice to Parent of at least two (2) Business Days and negotiating with Parent in good faith in an effort to amend the terms and conditions of the Merger Agreement, so that such Superior Proposal no longer constitutes a “Superior Proposal” relative to the transactions contemplated by the Merger Agreement, as amended pursuant to such negotiations.

If Stamps.com terminates the Merger Agreement prior to the adoption of the Merger Agreement by Stamps.com stockholders for the purpose of entering into an agreement in respect of a Superior Proposal, other than entering into an agreement in respect of a Superior Proposal with an Excluded Party prior to the No-Shop Period, then Stamps.com must pay a $199,000,000 termination fee to Parent.

As described above, and subject to the provisions described below, the Board of Directors has made the recommendation that the holders of shares of Stamps.com common stock vote “FOR” the proposal to adopt the Merger Agreement. The Merger Agreement provides that the Board of Directors will not effect a Company Board Recommendation Change except as described below.

Prior to the adoption of the Merger Agreement by stockholders (or in the case of a failure of the Board of Directors to publicly reaffirm its recommendation to approve the Merger within ten business days after Parent so requests in writing (it being understood that Stamps.com will have no obligation to make such reaffirmation on more than two occasions), after the No-Shop Period Start Date), the Board of Directors may not take any action described in the following (any such action, a “Company Board Recommendation Change”):

For the avoidance of doubt, none of the following, among other things, will constitute a Company Board Recommendation Change: (1) a “stop, look and listen” communication by the Board of Directors (or a committee thereof) to Stamps.com stockholders pursuant to Rule 14d-9(f) promulgated under the Exchange Act (or any substantially similar communication), (2) the factually accurate public disclosure by Stamps.com of the receipt of an Acquisition Proposal, (3) the determination by the Board of Directors (or a committee thereof) that an Acquisition Proposal constitutes a Superior Proposal, or (4) delivery by the Company to Parent of any notice related to an Intervening Event (as defined below) or Superior Proposal as set forth below.

Notwithstanding the restrictions described above, prior to the adoption of the Merger Agreement by stockholders, the Board of Directors may effect a Company Board Recommendation Change if there has been an Intervening Event (as defined below), if the Board of Directors (or committee thereof) has concluded in good faith (after consultation with its financial advisor and outside legal counsel) that the failure to do so would be reasonably likely to be inconsistent with its fiduciary duties pursuant to applicable law.

The Board of Directors may only effect a Company Board Recommendation Change for an Intervening Event if:

In addition, the Board of Directors may only effect a Company Board Recommendation Change or authorize Stamps.com to terminate the Merger Agreement to enter into an agreement with respect to a Superior Proposal substantially concurrently with the termination of the Merger Agreement in response to a bona fide Acquisition Proposal that the Board of Directors has concluded in good faith (after consultation with its financial advisor and outside legal counsel) is a Superior Proposal, in each case if and only if:

For purposes of this proxy statement and the Merger Agreement, an “Intervening Event” means any material change, event, effect or circumstance or material change in circumstances or facts (including any change in probability or magnitude of circumstances) that (a) was not known to or reasonably foreseeable by the Company Board on the date of the Merger Agreement (or if known by the Company Board, the consequences of which were not known to or reasonably foreseeable by the Company Board as of the date of the Merger Agreement) and becomes known to the Company Board prior to the receipt of the Requisite Stockholder Approval and (b) does not relate to (i) any Acquisition Proposal or (ii) the mere fact, in and of itself, that Stamps.com meets or exceeds any internal or published projections, forecasts, estimates or predictions of revenue, earnings, or other financial or operating metrics for any period ending on or after the date of the Merger Agreement, or changes after the date of the Merger Agreement in the market price or trading volume of Stamps.com common stock or the credit rating of Stamps.com (it being understood that the underlying cause of any of the foregoing in this clause (ii) may be considered and taken into account).

The Merger Agreement provides that from and after the Effective Time through one year following the Effective Time, Parent will cause the Surviving Corporation to honor all of the terms of Stamps.com’s employee plans and arrangements set forth in the confidential disclosure letter to the Merger Agreement following the Merger in accordance with their terms as in effect on the date of the Merger Agreement, subject to the Surviving Corporation’s right to amend or terminate any such benefit plan in accordance with its terms or if otherwise required pursuant to applicable law. In addition, for a period of one year following the Effective Time, each employee who continues employment following the Merger (a “Continuing Employee”) will be provided with (i) a base salary or wage rate at least as favorable as such Continuing Employee’s base salary or wage rate immediately prior to the Effective Time, (ii) short-term cash bonus or cash commission compensation opportunities that are substantially comparable in the aggregate to such compensation opportunities the Continuing Employee received as of immediately prior to the Effective Time under the applicable employee plans as set forth on the confidential disclosure letter, (iii) vacation, paid time off, qualified defined contribution retirement, health and welfare and other employee benefits (excluding any equity, equity-based benefits, defined benefit pension plans and/or nonqualified deferred compensation plans) that are substantially comparable in the aggregate to those provided to the Continuing Employee immediately prior to the Effective Time under the employee plans and arrangements as set forth on the confidential disclosure letter, and (iv) severance payments and benefits that are substantially comparable in the aggregate to the severance payments and benefits that each such Continuing Employee would have been eligible to receive immediately prior to the Effective Time under the employee plans as set forth on the confidential disclosure letter.

The Surviving Corporation will grant any Continuing Employee credit for service with the Company Group prior the Effective Time for purposes of eligibility to participate, vesting and entitlement to benefits where length of service is relevant (including for purposes of vacation accrual and severance pay entitlement, but not including for any

purpose under equity or equity-based benefit or compensation arrangements) to the same extent and for the same purpose as such service was credited to such person under the corresponding employee benefit plan as of the Effective Time, except where the service credit would result in duplication of coverage or benefits. Each Continuing Employee will be immediately eligible to participate, without any waiting period, in any and all employee benefit plans sponsored by the Surviving Corporation (other than Stamps.com’s benefit plans and arrangements in existence immediately before the Effective Time) to the extent that coverage under any of the employee benefit plans sponsored by the Surviving Corporation replaces at the Effective Time coverage under a comparable Stamps.com benefit plan or arrangement in which the Continuing Employee participates immediately before the Effective Time. For purposes of each employee benefit plan sponsored by the Surviving Corporation that provides medical, dental, pharmaceutical, vision or disability benefits to any Continuing Employee, the Surviving Corporation will use commercially reasonable efforts to cause all waiting periods, pre-existing condition exclusions, evidence of insurability requirements and actively-at-work or similar requirements of the plan to be waived for the Continuing Employee and his or her covered dependents to the same extent waived under the corresponding comparable Stamps.com benefit plan or arrangement in which the Continuing Employee participates immediately before the Effective Time, and the Surviving Corporation will use commercially reasonable efforts to cause full credit to be given for any eligible expenses incurred by the Continuing Employee and his or her covered dependents during the portion of the plan year of the comparable Stamps.com benefit plan or arrangement in which the Continuing Employee participates immediately before the Effective Time that ends on the date that the Continuing Employee’s participation in the corresponding employee benefit plan sponsored by the Surviving Corporation begins for purposes of satisfying the applicable deductible, coinsurance, co-pay, offsets and maximum out-of-pocket requirements applicable to the Continuing Employee and his or her covered dependents for the applicable plan year as if the amounts had been paid according to the employee benefit plan of the Surviving Corporation to the same extent as such amounts were credited for the same purpose under the corresponding comparable Stamps.com benefit plan or arrangement in which the Continuing Employee participates immediately before the Effective Time. The account of each Continuing Employee under any flexible spending plan sponsored will be credited by the Surviving Corporation with any unused balance in the account of the Continuing Employee. Any vacation or paid time off accrued but unused by a Continuing Employee as of immediately before the Effective Time will be credited to the Continuing Employee following the Effective Time, and will not be subject to accrual limits or other forfeiture and will not limit future accruals (except to the extent that the limits or forfeitures applied under Stamps.com’s benefit plans and arrangements in effect as of the date of the Merger Agreement).

From and after the Effective Time, Parent will cause the Surviving Corporation to honor in accordance with their terms the Annual Bonus Plans with respect to the 2021 calendar year and, to the extent the Effective Time occurs in calendar year 2022, in a manner consistent with past practice. In addition, Parent shall cause the Surviving Corporation to pay, at a time no later than the time customarily paid by the Company related to any Annual Bonus Plan, to each employee of Stamps.com or any of its subsidiaries actively employed on the applicable payment dates for the 2021 and 2022 bonuses who is then participating in any Annual Bonus Plan, respectively, a bonus based on actual performance, in a manner consistent with past practice and in accordance with the terms of such Annual Bonus Plan.

Under the Merger Agreement, Parent, Merger Sub and Stamps.com agreed to use reasonable best efforts to take all actions and assist and cooperate with the other parties, in each case as necessary, proper and advisable pursuant to applicable law or otherwise to consummate the Merger.

Although the obligation of Parent and Merger Sub to consummate the Merger is not subject to any financing condition (including, without limitation, consummation of any debt financing), Stamps.com has agreed that during the Interim Period, Stamps.com will use commercially reasonable efforts to, and will use its reasonable efforts to cause each of its subsidiaries and its and their respective representatives to, among other things:

Notwithstanding the foregoing, neither Stamps.com nor any of its subsidiaries is required to (1) waive or amend any terms of the Merger Agreement or agree to pay any fees or reimburse any expenses prior to the Effective Time for which they have not received prior reimbursement or are not otherwise indemnified by or on behalf of Parent; (2) enter into any definitive agreement or distribute any cash (except to the extent subject to concurrent reimbursement by Parent) that will be effective prior to the Effective Time; (3) give any indemnities in connection with the cooperation requirements described herein that are, in each case, effective prior to the Effective Time; (4) take any action that, in their good faith determination would unreasonably interfere with the conduct of their business, breach any confidentiality obligations or create an unreasonable risk of damage or destruction to any of their property or assets; (5) take any action that will conflict with or violate their respective organizational documents or any applicable laws or would result in a material violation or breach of, or default under, any material agreement to which Stamps.com is a party; or (6) provide any information the disclosure of which is prohibited or restricted under applicable Law or is legally privileged. In addition, (1) no action, liability or obligation of the Company Group or any of their respective representatives pursuant to any certificate, agreement, arrangement, document or instrument relating to the Debt Financing or any of the actions required to be taken by the Company Group pursuant to the cooperation requirements described herein (other than with respect to customary authorization letters required for the syndication of the Debt Financing) will be effective until the Effective Time, and the Company Group will not be required to take any action pursuant to any certificate, agreement, arrangement, document or instrument (other than with respect to customary authorization letters required for the syndication of the Debt Financing) that is not contingent on the occurrence of the closing or that must be effective prior to the Effective Time; and (2) any bank information memoranda required in relation to the Debt Financing will contain disclosure reflecting the Surviving Corporation as the obligor. No officer or representative of the Company Group shall be required to deliver any certificate or opinion or take any other action pursuant to the cooperation requirements described herein that could reasonably be expected to result in personal liability to such officer or representative and the Board of Directors shall not be required to approve any financing or agreements related thereto, that are, in each case, effective prior to the Effective Time. Stamps.com shall not be deemed to have breached or failed to perform or observe any covenants, obligations or other agreements contained in the Merger Agreement relating to the Debt Financing, in each case, unless the Debt Financing has not been obtained solely as a result of Stamps.com’s willful breach.

In addition, Parent shall (1) reimburse the Company Group for any documented and reasonable out-of-pocket costs and expenses (including attorneys’ fees) incurred by Stamps.com in connection with the cooperation requirements described herein and (2) indemnify the Company Group and its respective representatives from and against any and all liabilities, losses, damages, claims, costs, expenses (including attorneys’ fees), interest, awards, judgments, penalties and amounts paid in settlement suffered or incurred by them in connection with any cooperation described herein, except to the extent resulting from Stamps.com’s and its subsidiaries’ or any of their respective representatives’ bad faith or willful and material misconduct.

The Merger Agreement provides that all existing rights to exculpation, indemnification and the advancement of expenses for acts or omissions occurring at or prior to the Effective Time existing as of the signing of the Merger Agreement in favor of the current or former directors, officers or employees of Stamps.com (in each case, as provided in the respective organizational documents of Stamps.com and as provided in any indemnification agreements between Stamps.com and any such person) will survive the Merger and will continue in full force and effect for a period of six years from the Effective Time, in each case, except as otherwise required by applicable law.

In addition, the Merger Agreement provides that, during the six-year period commencing at the Effective Time, the Surviving Corporation will (and Parent must cause the Surviving Corporation to) indemnify and hold harmless each current or former director, officer or employee of the Company Group, to the fullest extent permitted by law or pursuant to the organizational documents of Stamps.com and as provided in any indemnification agreements between Stamps.com and any such person, from and against all costs, fees and expenses (including attorneys’ fees and investigation expenses), judgments, fines, losses, claims, damages, liabilities and amounts paid in settlement or compromise in connection with any legal proceeding arising, directly or indirectly, out of or pertaining, directly or indirectly, to (1) any action or omission, or alleged action or omission, in such indemnified person’s capacity as a

director, officer, employee or agent of the Company Group or other affiliates to the extent that such action or omission, or alleged action or omission, occurred prior to or at the Effective Time; and (2) the Merger, as well as any actions taken by Stamps.com, Parent or Merger Sub with respect thereto. The Merger Agreement also provides that the Surviving Corporation will (and Parent must cause the Surviving Corporation to) advance all fees and expenses (including fees and expenses of any counsel) as incurred by any such indemnified person in the defense of such legal proceeding.

In addition, without limiting the foregoing, unless Stamps.com has purchased a “tail” policy prior to the Effective Time (which Stamps.com may purchase, provided that the premium for such insurance does not exceed 300% of the aggregate annual premiums paid by the Company Group for its last full fiscal year), the Merger Agreement requires Parent to cause the Surviving Corporation to maintain, on terms no less advantageous to the indemnified parties, the directors’ and officers’ insurance policies of the Company Group for a period of six years commencing at the Effective Time. Neither Parent nor the Surviving Corporation will be required to pay premiums for such policy to the extent such premiums exceed, on an annual basis, 300% of the aggregate annual premiums paid by the Company Group for its last full fiscal year, and if the premium for such insurance coverage would exceed such amount, Parent shall be obligated to cause the Surviving Corporation to obtain the greatest coverage available for a cost equal to such amount.

For more information, please refer to the section of this proxy statement captioned “The Merger—Interests of Stamps.com’s Directors and Executive Officers in the Merger.”

Stamps.com has agreed to take all necessary action (in accordance with applicable Delaware law, Stamps.com’s organizational documents and the rules of Nasdaq) to establish a record date for, duly call, give notice of, convene and hold a Special Meeting of the stockholders as promptly as reasonably practicable following the mailing of this proxy statement for the purpose of voting upon the adoption of the Merger Agreement, and approval of the Merger. The Special Meeting of the stockholders cannot be held later than 45 days after the date upon which Stamps.com receives confirmation from the SEC that it will not review, or that it has completed its review of this proxy statement (which confirmation will be deemed to occur if the SEC has not affirmatively notified Stamps.com prior to the tenth calendar day after filing this proxy statement that the SEC will or will not be reviewing this proxy statement).

At all times prior to the earlier to occur of the termination of the Merger Agreement in accordance with its terms and the Effective Time, Stamps.com will: (1) control the defense of any stockholder litigation; (2) provide Parent with prompt notice of all stockholder litigation relating to the Merger Agreement; (3) keep Parent reasonably informed with respect to status thereof; (4) give Parent the opportunity to participate (at Parent’s sole cost and expense) in the defense, settlement or prosecution of any such litigation; and (5) will consult with Parent with respect to the defense, settlement or prosecution of such litigation. Stamps.com may not settle any such litigation without Parent’s prior written consent (such consent not to be unreasonably withheld, delayed or conditioned).

The obligations of Parent and Merger Sub, on the one hand, and Stamps.com, on the other hand, to consummate the Merger is subject to the satisfaction or waiver (where permitted by applicable Law) of each of the following conditions:

In addition, the obligations of Parent and Merger Sub to consummate the Merger are subject to the satisfaction or waiver (where permitted by applicable Law) of each of the following additional conditions:

In addition, the obligation of Stamps.com to consummate the Merger is subject to the satisfaction or waiver (where permitted by applicable Law) of each of the following additional conditions:

None of Parent, Merger Sub, or Stamps.com may rely on a failure of a condition set forth above in this section titled “Conditions to the Closing of the Merger” to be satisfied as a basis for not consummating the Merger or any of the other transactions contemplated by the Merger Agreement or terminating the Merger Agreement and abandoning the Merger if such failure was caused by a failure to act in good faith or use requisite efforts to cause the closing of the Merger to occur as required by the Merger Agreement.

The Merger Agreement may be terminated, and the transactions (including the Merger) may be abandoned, at any time prior to the Effective Time, whether before or after the adoption of the Merger Agreement by stockholders, in the following ways:

In the event that the Merger Agreement is terminated pursuant to the termination rights above, the Merger Agreement will be of no further force or effect without liability of any party to the other parties, as applicable, except that certain sections of the Merger Agreement will survive the termination of the Merger Agreement in accordance with their respective terms, including terms relating to reimbursement of expenses and indemnification. Notwithstanding the foregoing, nothing in the Merger Agreement will relieve any party from any liability for any fraud or willful and material breach of the Merger Agreement prior to its termination. In addition, no termination of the Merger Agreement will affect the rights or obligations of any party pursuant to the confidentiality agreement between Thoma Bravo and Stamps.com or the Guaranty, which rights, obligations and agreements will survive the termination of the Merger Agreement in accordance with their respective terms.

If Stamps.com terminates the Merger Agreement for the purposes of entering into a definitive agreement with any Excluded Party prior to the No-Shop Period Start Date in respect of a Superior Proposal, Stamps.com would be required to pay a $99,500,000 termination fee to Parent. If the Merger Agreement is terminated under specified circumstances including the instances described below, Stamps.com must pay a $199,000,000 termination fee to Parent.

Parent will be entitled to receive a termination fee of $199,000,000 from Stamps.com if the Merger Agreement is terminated:

Stamps.com will be entitled to receive a termination fee of $365,000,000 from Parent (the “Parent Termination Fee”) if the Merger Agreement is terminated:

Parent, Merger Sub and Stamps.com have agreed that irreparable damage for which monetary damages, even if available, would not be an adequate remedy would occur in the event that the parties do not timely perform the provisions of the Merger Agreement (including any party failing to take such actions as are required of it in order to consummate the Merger Agreement). Parent, Merger Sub and Stamps.com acknowledge and have agreed that: (1) the parties will be entitled, in addition to any other remedy to which they are entitled at law or in equity, to an injunction, specific performance and other equitable relief to prevent breaches (or threatened breaches) of the Merger Agreement and to enforce specifically the terms and provisions thereof; (2) the fees and expenses provisions of the Merger Agreement are not intended to and would not adequately compensate Stamps.com, on the one hand, or Parent and Merger Sub, on the other hand, for the harm that would result from a breach of the Merger Agreement, and will not be construed to diminish or otherwise impair in any respect any party’s right to an injunction, specific performance and other equitable relief; and (3) the right of specific enforcement is an integral part of the Merger and without that right, neither Stamps.com nor Parent would have entered into the Merger Agreement. It is explicitly agreed that Stamps.com will have the right to an injunction, specific performance or other equitable remedies in connection with enforcing Parent’s and Merger Sub’s obligations to consummate the Merger and cause the financing to be funded to fund the Merger (including to cause Parent to enforce the obligations of the Guarantor under the Financing Letters in order to cause the financing to be timely completed in accordance with and subject to the terms and conditions set forth in the Financing Letters) subject to the terms and conditions set forth therein and in the Merger Agreement. Notwithstanding anything to the contrary in the Merger Agreement, it is explicitly agreed that the right of Stamps.com to seek an injunction, specific performance or other equitable remedies in connection with enforcing Parent’s obligation to cause the Equity Financing to be funded to fund a portion of the purchase price and other amounts required to be paid in connection with the closing of the Merger (but not the right of Stamps.com to seek such injunctions, specific performance or other equitable remedies for any other reason) shall be subject to the requirements that (A) all of the conditions set forth in the closing conditions have been, and continue to be, satisfied

(other than those conditions that by their terms are to be satisfied at the closing, but subject to the satisfaction or waiver (to the extent permitted hereunder) of such conditions), (B) the Debt Financing has been funded in accordance with the terms and conditions thereof or will be funded in accordance with the terms and conditions thereof if the Equity Financing is funded and (C) Stamps.com has irrevocably confirmed in writing that if the Equity Financing and Debt Financing are funded, then Stamps.com shall take such actions that are required of it by the Merger Agreement to consummate the closing pursuant to the terms of the Merger Agreement.

Parent, Merger Sub and Stamps.com have agreed not to raise any objections to (1) the granting of an injunction, specific performance or other equitable relief to prevent or restrain breaches or threatened breaches of the Merger Agreement by Stamps.com, on the one hand, or Parent and Merger Sub, on the other hand; and (2) the specific performance of the terms and provisions of the Merger Agreement to prevent breaches or threatened breaches of, or to enforce compliance with, the covenants, obligations and agreements of Parent and Merger Sub pursuant to the Merger Agreement. Any party seeking an injunction or injunctions to prevent breaches of the Merger Agreement and to enforce specifically the terms and provisions of the Merger Agreement will not be required to provide any bond or other security in connection with such injunction or enforcement, and each party irrevocably waives any right that it will have to require the obtaining, furnishing or posting of any such bond or other security. Each of the foregoing parties have also agreed that it will use reasonable best efforts to cooperate with the other parties in seeking and agreeing to an expedited schedule in any litigation seeking an injunction or order of specific performance to attempt to fully resolve any dispute before the Termination Date.

The maximum aggregate monetary damages of Parent, Merger Sub and any of their affiliates for breaches (including any willful breach (but excluding, for the avoidance of doubt, for actual and intentional common law fraud)) under the Merger Agreement (taking into account the payment of the Parent Termination Fee pursuant to the Merger Agreement), the Guaranty or the Equity Commitment Letter will not exceed an amount equal to $365,000,000 plus certain enforcement expenses relating to legal proceedings that result in a judgment against the payor and losses and liabilities in connection with cooperation relating to debt financing. The maximum aggregate monetary damages of Stamps.com for breaches (including any willful breach (but excluding, for the avoidance of doubt, for actual and intentional common law fraud)) under the Merger Agreement (taking into account the payment of the termination fee, if applicable) will not exceed an amount equal to $199,000,000 plus the enforcement expenses (if any) in the aggregate for all such breaches. Notwithstanding such limitations on liability for monetary damages, Parent, Merger Sub and Stamps.com may be entitled to an injunction, specific performance or other equitable relief as provided in the Merger Agreement.

Except in specified circumstances, whether or not the Merger is completed, Stamps.com, on the one hand, and Parent and Merger Sub, on the other hand, are each responsible for all of their respective costs and expenses incurred in connection with the Merger and the other transactions contemplated by the Merger Agreement.

The Merger Agreement may be amended by the parties in an executed written instrument at any time before or after adoption of the Merger Agreement by stockholders. However, after adoption of the Merger Agreement by stockholders, no amendment that requires further approval by such stockholders pursuant to the DGCL may be made without such approval.

The Merger Agreement is governed by Delaware law.

Certain of Stamps.com’s officers, Ken McBride, Jeff Carberry, Matt Lipson, John Clem and Nathan Jones, have entered into voting agreements (the “Voting Agreements”) with Stamps.com and Parent pursuant to which each such officer has agreed, among other things, to vote their respective shares of Common Stock in favor of adoption of the Merger Agreement and approval of the Merger, and against any competing transaction, so long as, among other things, the Merger Agreement remains in effect. The Voting Agreements cannot be amended without Stamps.com’s consent.

The affirmative vote of the holders of a majority of the outstanding shares of Stamps.com common stock is required to approve and adopt the Merger Agreement. Adoption of the Merger Agreement by stockholders is a condition to the closing of the Merger. If a stockholder abstains from voting, that abstention will have the same effect as if the stockholder voted “AGAINST” the proposal to adopt the Merger Agreement. Each “broker non-vote” (if any) will also count as a vote “AGAINST” the proposal to adopt the Merger Agreement. Shares of Stamps.com common stock represented by properly executed, timely received and unrevoked proxies will be voted in accordance with the instructions indicated thereon. If a Stamps.com stockholder returns a signed proxy card without indicating voting preferences on such proxy card, the shares of Stamps.com common stock represented by that proxy will be counted as present for purposes of determining the presence of a quorum for the Special Meeting and all of such shares will be voted as recommended by the Board of Directors.

The Board of Directors unanimously recommends that you vote “FOR” this proposal.

Under Section 14A of the Exchange Act and the applicable SEC rules issued thereunder, Stamps.com is required to submit a proposal to our stockholders to approve, on an advisory (non-binding) basis, the compensation that may be paid or become payable to Stamps.com’s named executive officers that is based on or otherwise relates to the Merger Agreement and the transactions contemplated by the Merger Agreement. This compensation is summarized in the section captioned “The Merger—Interests of Stamps.com’s Directors and Executive Officers in the Merger.” The Board of Directors encourages you to review carefully the named executive officer merger-related compensation information disclosed in this proxy statement. Accordingly, Stamps.com is asking you to approve the following resolution:

“RESOLVED, that the stockholders of Stamps.com approve, on a non-binding, advisory basis the compensation that may be paid or become payable to Stamps.com’s named executive officers that is based on or otherwise relates to the merger as disclosed pursuant to Item 402(t) of Regulation S-K in the section entitled “The Merger—Interests of Stamps.com’s Directors and Executive Officers in the Merger.”

The vote on this Compensation Proposal is a vote separate and apart from the vote on the proposal to adopt the Merger Agreement. Accordingly, you may vote to approve the proposal to adopt the Merger Agreement and vote not to approve this Compensation Proposal and vice versa. Because the vote on the Compensation Proposal is advisory only, it will not be binding on Stamps.com. Accordingly, if the Merger Agreement is adopted and the Merger is completed, the compensation will be payable, subject only to the conditions applicable thereto, regardless of the outcome of the vote on this Compensation Proposal.

Approval, on an advisory (non-binding) basis, of the Compensation Proposal requires the affirmative vote of the holders of a majority of the shares of Stamps.com common stock virtually present in person, by remote communication, or represented by proxy at the Special Meeting and entitled to vote on the subject matter. Assuming a quorum is present, (1) a failure to vote in person or by proxy at the Special Meeting will have no effect on the outcome of the Compensation Proposal, (2) abstentions will have the same effect as a vote against the Compensation Proposal and (3) broker “non-votes” (if any) will have no effect on the outcome of the Compensation Proposal. Shares of Stamps.com common stock represented by properly executed, timely received and unrevoked proxies will be voted in accordance with the instructions indicated thereon. If a Stamps.com stockholder returns a signed proxy card without indicating voting preferences on such proxy card, the shares of Stamps.com common stock represented by that proxy will be counted as present for purposes of determining the presence of a quorum for the Special Meeting and all of such shares will be voted as recommended by the Board of Directors.

The Board of Directors unanimously recommends that you vote “FOR” this proposal.

We are asking you to approve a proposal to adjourn the Special Meeting from time to time, if necessary or appropriate as determined in the discretion of the Board of Directors or the Chairman of the Board of Stamps.com, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting. If stockholders approve the Adjournment Proposal, we could adjourn the Special Meeting and any adjourned session of the Special Meeting and use the additional time to solicit additional proxies, including soliciting proxies from stockholders that have previously returned properly executed proxies voting against adoption of the Merger Agreement. Among other things, approval of the Adjournment Proposal could mean that, even if we had received proxies representing a sufficient number of votes against adoption of the Merger Agreement such that the proposal to adopt the Merger Agreement would be defeated, we could adjourn the Special Meeting without a vote on the adoption of the Merger Agreement and seek to convince the holders of those shares to change their votes to votes in favor of adoption of the Merger Agreement. Additionally, we may seek to adjourn the Special Meeting if a quorum is not present or otherwise at the discretion of the chairman of the Special Meeting. Approval of the Adjournment Proposal whether or not a quorum is present, requires the affirmative vote of the holders of a majority of the shares virtually present in person, by remote communication or represented by proxy at the Special Meeting and entitled to vote on the subject matter.

The Board of Directors unanimously recommends that you vote “FOR” this proposal.

If the Merger is completed, we will have no public stockholders and there will be no public participation in any future meetings of stockholders of Stamps.com. However, if the Merger is not completed, stockholders will continue to be entitled to attend and participate in stockholder meetings.

Stamps.com will hold the regular annual meeting of its stockholders in 2022 only if the Merger is not completed.

Under SEC Rule 14a-8, proposals of stockholders that are intended to be presented by such stockholders at our 2022 annual meeting of stockholders and included in the proxy statement and form of proxy relating to that meeting must be received no later than January 3, 2022. Stockholders wishing to submit proposals for the 2022 annual meeting of stockholders outside of Rule 14a-8 may do so if the proposal was timely received by us under our bylaws, as calculated below. In addition, subject to SEC Rule 14a-4(c), the proxy solicited by our Board of Directors for the 2022 annual meeting of stockholders will confer discretionary authority to vote on any stockholder proposal presented at that meeting if notice of the proposal was not timely received by us under our bylaws, as calculated below. Our bylaws provide that to be timely, notice of a nomination for director or other proposal must be delivered to or mailed and received at our principal executive offices not less than 120 days nor more than 150 days before the one year anniversary of the date of the preceding year's annual meeting (unless the date of the annual meeting is more than 30 days in advance, or 60 days after, the anniversary of prior year’s annual meeting). For our 2022 annual meeting of stockholders, to be timely stockholders must submit a nomination for director or other proposal no later than February 9, 2022, and no earlier than January 10, 2022.

The SEC allows us to “incorporate by reference” information into this proxy statement, which means that we can disclose important information to you by referring you to other documents filed separately with the SEC. The information incorporated by reference is deemed to be part of this proxy statement, except for any information superseded by information in this proxy statement or incorporated by reference subsequent to the date of this proxy statement. This proxy statement incorporates by reference the documents set forth below that we have previously filed with the SEC. These documents contain important information about us and our financial condition and are incorporated by reference into this proxy statement.

The following Stamps.com filings with the SEC are incorporated by reference:

We also incorporate by reference into this proxy statement additional documents that we may file with the SEC between the date of this proxy statement and the earlier of the date of the Special Meeting or the termination of the Merger Agreement. These documents include periodic reports, such as Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q, as well as Current Reports on Form 8-K and proxy soliciting materials. The information provided on our website is not part of this proxy statement, and therefore is not incorporated by reference herein.

Information furnished under Item 2.02 or Item 7.01 of any Current Report on Form 8-K, including related exhibits, is not and will not be incorporated by reference into this proxy statement.

These SEC filings are also available to the public from commercial document retrieval services and at www.sec.gov.

You may obtain any of the documents we file with the SEC, without charge, by requesting them in writing or by telephone from us at the following address:

Stamps.com Inc.

Attention: Investor Relations

1990 E. Grand Avenue

El Segundo, CA 90245

If you would like to request documents from us, please do so as soon as possible, to receive them before the Special Meeting. If you request any documents from us, we will mail them to you by first class mail, or another equally prompt method, within one business day after we receive your request. Please note that all of our documents that we file with the SEC are also promptly available through our website at https://investor.Stamps.com and clicking on the link titled “SEC Filings.” The information included on our website is not incorporated by reference into this proxy statement.

If you have any questions concerning the Merger, the Special Meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of Stamps.com common stock, please contact our proxy solicitor:

D.F. King & Co, Inc.

48 Wall Street, 22nd Floor

New York, New York 10005

Banks and Brokers, Call Collect: (212) 269-5550

All Others Call Toll Free: (800) 761-6521

Email: [email protected]

Stamps.com has supplied all information relating to Stamps.com, and Parent has supplied, and Stamps.com has not independently verified, all of the information relating to Parent and Merger Sub contained in this proxy statement.

You should rely only on the information contained in this proxy statement, the annexes to this proxy statement and the documents that we incorporate by reference in this proxy statement in voting on the Merger. We have not authorized anyone to provide you with information that is different from what is contained in this proxy statement. You should not assume that the information contained in this proxy statement is accurate as of any date other than the date of this proxy statement (or as of an earlier date if so indicated in this proxy statement), and the mailing of this proxy statement to stockholders does not create any implication to the contrary. This proxy statement does not constitute a solicitation of a proxy in any jurisdiction where, or to or from any person to whom, it is unlawful to make a proxy solicitation.