PCMI PCM Inc

Notice of Special Meeting of Stockholders
To Be Held on August 26, 2019

        Notice is hereby given that a Special Meeting of Stockholders of PCM, Inc., a Delaware corporation ("PCM"), will be held at PCM's headquarters, located at 1940 E. Mariposa Avenue, El Segundo, CA 90245 on August 26, 2019 at 8:00 a.m. local time for the following purposes, as more fully described in the proxy statement accompanying this notice:

        1.     To consider and vote on a proposal to adopt the Agreement and Plan of Merger, dated as of June 23, 2019, as it may be amended from time to time, which we refer to as the merger agreement, by and among PCM, Insight Enterprises, Inc., a Delaware corporation, which we refer to as Insight, and Trojan Acquisition Corp., a Delaware corporation and a wholly-owned subsidiary of Insight, which we refer to as Merger Sub. A copy of the merger agreement is attached as Annex A to the accompanying proxy statement.

        2.     To consider and vote on the advisory (non-binding) proposal, which we refer to as the compensation proposal, to approve certain compensation that may be paid or become payable to the Named Executive Officers of PCM in connection with the merger.

        3.     To consider and vote on the proposal, which we refer to as the adjournment proposal, to approve the adjournment of the special meeting from time to time, if necessary or appropriate as determined by the PCM board of directors, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement or if a quorum is not present at the special meeting.

        The merger agreement, the merger and the other transactions which would be effected in connection with the merger are described more fully in the attached proxy statement, and we urge you to read the attached proxy statement carefully and in its entirety. Your vote is very important, regardless of the number of shares of PCM's common stock you own.

         The PCM board of directors recommends that PCM stockholders vote (i) "FOR" the proposal to adopt the merger agreement, (ii) "FOR" the compensation proposal and (iii) "FOR" the adjournment proposal.

        Whether or not you plan to attend the special meeting, please complete, date, sign and return, as promptly as possible, the enclosed proxy card in the accompanying postage-paid reply envelope, or submit your proxy by telephone or the Internet. If your shares of common stock are held through a bank, brokerage firm or other nominee in "street-name," only your bank, brokerage firm or other nominee can vote your shares and only upon receipt of your specific instructions. Please return the voting instruction form in the envelope provided to your bank, brokerage firm or other nominee and contact the person responsible for your account to ensure that a proxy card is voted on your behalf. If your bank, brokerage firm or other nominee provides for voting instructions to be delivered to them by Internet or telephone, instructions to do so will be included on the voting instruction form provided by such nominee. If you fail to return your proxy card, submit your proxy by telephone or the Internet or vote in person, or if your shares are held in "street name" by your bank, brokerage firm or other nominee and you fail to instruct your bank, brokerage firm or other nominee to vote your shares of

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common stock in accordance with the instructions provided by such nominee, your shares of our common stock will not be counted for purposes of determining whether a quorum is present at the special meeting and will have the same effect as a vote "AGAINST" the adoption of the merger agreement.

        You may revoke your proxy before the special meeting by voting over the Internet or by telephone (only your latest Internet or telephone vote is counted) or by signing a new proxy and mailing it, in each case, in accordance with the instructions on the enclosed proxy card. In addition, you may revoke your proxy by attending the special meeting, requesting that your proxy be revoked and voting in person; however, attending the special meeting will not revoke your Internet vote, telephone vote or proxy, as the case may be, unless you specifically request it.

        The PCM board of directors has fixed the close of business on July 22, 2019 as the record date for determination of stockholders entitled to receive notice of, and to vote at, the special meeting and any adjournments or postponements thereof. Only stockholders of record at the close of business on the record date are entitled to receive notice of, and to vote (in person or by proxy) at the special meeting and at any adjournment or postponement thereof.

        If the merger is completed, PCM stockholders of record who do not vote in favor of the proposal to adopt the merger agreement and otherwise comply with the requirements set forth in Section 262 of the General Corporation Law of the State of Delaware, which we refer to as the DGCL, will be entitled to seek appraisal for the judicially determined fair value of their shares of PCM common stock in connection with the merger, which may be more than, less than or the same as the per share merger consideration. See the section entitled "Stockholder Appraisal Rights" beginning on page 89 of this proxy statement and Annex D to this proxy statement for more information on stockholder appraisal rights.

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QUESTIONS AND ANSWERS ABOUT THE SPECIAL MEETING AND THE MERGER

        The following questions and answers are intended to briefly address some commonly asked questions regarding the merger, the merger agreement and the special meeting. These questions and answers may not address all questions that may be important to you as a PCM stockholder. To better understand the merger, the merger agreement and the special meeting, please carefully read this entire proxy statement, including the annexes and other documents incorporated by reference herein. You may obtain the information incorporated by reference into this proxy statement without charge by following the instructions under the section entitled "Where You Can Find More Information" beginning on page 98 of this proxy statement.

Q:    Why am I receiving this proxy statement and proxy or voting instruction card?

A:

PCM is sending these materials to the holders, whom we refer to collectively as PCM stockholders, of its common stock, par value $0.001 per share, which we refer to as the PCM common stock, to help them decide how to vote their shares of PCM common stock with respect to the merger and other matters to be considered at the special meeting. The merger cannot be completed unless PCM stockholders adopt the merger agreement, which requires the affirmative vote at the special meeting of the holders of a majority of the outstanding shares of PCM common stock entitled to vote on the proposal to adopt the merger agreement, which we refer to as the requisite company vote. PCM stockholders are also being asked to approve the compensation proposal (on an advisory basis) and the adjournment proposal.

This proxy statement includes important information about the merger, the merger agreement and the special meeting. PCM stockholders should read this information carefully and in its entirety. The enclosed voting materials allow stockholders to vote their shares without attending the special meeting in person.

About the Merger

Q:    What is the merger?

A:

PCM, Insight and Merger Sub have entered into an Agreement and Plan of Merger, dated as of June 23, 2019, which we refer to as the merger agreement. A copy of the merger agreement is attached as Annex A to this proxy statement and is incorporated by reference herein. The merger agreement contains the terms and conditions of the proposed business combination in which Merger Sub will be merged with and into PCM, which we refer to as the merger, with PCM surviving the merger, which we refer to as the surviving corporation, as a wholly-owned subsidiary of Insight. A summary of the merger agreement may be found in the section entitled "The Merger Agreement," beginning on page 65 of this proxy statement.

Q:    What will I receive if the merger is completed?

A:

If the merger is completed, PCM's stockholders will have the right to receive, in exchange for each share of PCM common stock that they own immediately prior to the effective time, $35.00 per share in cash, without interest and less applicable withholding taxes.

Q:    What will holders of PCM equity compensation awards receive in the merger?

A:

Each option to acquire shares of PCM common stock, which we refer to as a PCM stock option, whether vested or unvested, that is outstanding and unexercised immediately prior to the effective time will be, automatically and without any action on the part of the holder, deemed to be vested, cancelled and only entitle the holder of such stock option to receive (without interest and less applicable withholding taxes), at or as soon as reasonably practicable after the effective time, an

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amount in cash equal to the product of (i) the number of unexercised shares subject to such stock option immediately prior to the effective time multiplied by (ii) the excess of (A) the per share merger consideration over (B) the exercise price per share of such stock option. For purposes of this calculation, the vesting of any stock option subject to performance conditions will be fully accelerated and deemed achieved contingent and effective upon the closing of the merger. For additional information on the PCM stock options, see the section entitled "The Merger Agreement—Treatment of PCM Stock Options" beginning on page 66 of this proxy statement.

Additionally, each outstanding award of restricted stock units under PCM's 2012 Equity Incentive Plan, which we refer to as the PCM RSUs, whether vested or unvested, that is outstanding immediately prior to the effective time will be, automatically and without any action on the part of the holder, deemed to be vested, be cancelled and only entitle the holder of such PCM RSU to receive (without interest and less any applicable withholding taxes), at or as soon as reasonably practicable after the effective time, an amount in cash equal to the per share merger consideration plus any accrued and unpaid dividend equivalents with respect to such PCM RSU. For additional information on the PCM RSUs, see the section entitled "The Merger Agreement—Treatment of PCM Restricted Stock Units (RSUs)" beginning on page 66 of this proxy statement.

Q:    If I do not vote in favor of the adoption of the merger agreement, do I have appraisal rights?

A:

Under Section 262 of the DGCL, PCM stockholders of record who do not vote in favor of the proposal to adopt the merger agreement and otherwise comply with the requirements set forth in Section 262 of the DGCL will be entitled to seek appraisal and obtain payment in cash for the judicially determined fair value of their shares of PCM common stock in connection with the merger, if the merger is completed. This value could be more than, less than or the same as the implied value of the per share merger consideration for PCM common stock. The relevant provisions of the DGCL are included as Annex D to this proxy statement. We encourage you to read these provisions carefully and in their entirety. Moreover, due to the complexity of the procedures for exercising the right to seek appraisal, PCM stockholders who are considering exercising such rights are encouraged to seek the advice of legal counsel. Failure to strictly comply with these provisions will result in a loss of the right of appraisal. An executed proxy card that does not contain voting instructions will, unless revoked, be voted in favor of the proposal to adopt the merger agreement.

Therefore, a PCM stockholder who submits a proxy and who wishes to exercise appraisal rights must mark " AGAINST " or " ABSTAIN " with respect to the proposal to adopt the merger agreement. PCM stockholders who wish to exercise their appraisal rights and hold shares in the name of a bank, broker, trust or other nominee must instruct their bank, broker, trust or other nominee to take the steps necessary to enable them to demand appraisal for their shares.

Q:    What are the conditions to the completion of the merger?

A:

In addition to the adoption of the merger agreement by PCM stockholders as described above, closing of the merger is subject to the satisfaction or, to the extent permitted by applicable law, waiver of a number of other conditions, including, among others, (i) the expiration or earlier termination of any waiting period applicable to the consummation of the merger under the HSR Act and any approval or clearance under any other antitrust laws and (ii) the absence of any applicable law or order that prohibits completion of the merger.

In addition, the obligations of Insight and Merger Sub to effect the merger are also subject to the satisfaction or waiver by Insight at or prior to the closing of the merger of the following additional conditions: (i) the accuracy of PCM's representations and warranties in the merger agreement, subject to certain materiality qualifications; (ii) the performance in all material respects by PCM of

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its obligations required to be performed by it under the merger agreement at or prior to the closing of the merger; (iii) the absence of a material adverse effect since the date of the merger agreement; (iv) receipt by Insight and Merger Sub of a certificate signed by the chief executive officer or chief financial officer of PCM certifying that the above conditions with respect to the accuracy of representations and warranties, performance of the obligations of PCM and no material adverse effect have been satisfied; and (v) that there be no pending action by any governmental authority that seeks, directly or indirectly, to restrain, enjoin or otherwise prohibit the consummation of the merger or the other transactions contemplated by the merger agreement.

PCM's obligation to effect the merger are subject to the satisfaction or waiver by PCM at or prior to the closing of the merger of the following additional conditions: (i) the accuracy of Insight's and Merger Sub's representations and warranties in the merger agreement, subject to certain materiality qualifications; (ii) that each of Insight and Merger Sub will have performed in all material respects all obligations required to be performed by such party under the merger agreement prior to the closing of the merger; and (iv) receipt of a certificate signed on behalf of Insight and Merger Sub by an officer of Insight certifying that the above conditions with respect to the accuracy of representations and warranties and performance of the obligations of Insight and Merger Sub have been satisfied.

For a more complete summary of the conditions that must be satisfied or waived prior to closing of the merger, see the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 82 of this proxy statement.

Q:    What are the material United States federal income tax consequences of the merger to PCM stockholders?

A:

The exchange of shares of PCM common stock for cash by a U.S. holder (as defined on page 87) will generally be taxable to such U.S. holder. A U.S. holder will generally recognize gain or loss for federal income tax purposes in an amount equal to the difference between the cash it receives pursuant to the merger and its adjusted tax basis in its shares of PCM common stock exchanged therefor. For a more complete summary of the material United States federal income tax consequences of the merger to PCM stockholders, see the section entitled "Material U.S. Federal Income Tax Consequences of the Merger for U.S. Holders" beginning on page 87 of this proxy statement.

The tax consequences of the merger to any particular stockholder will depend on that stockholder's particular facts and circumstances. Accordingly, you are urged to consult your own tax advisor as to the specific tax consequences of the merger.

Q:    What will happen to PCM as a result of the merger?

A:

If the merger is completed, Merger Sub will be merged with and into PCM, with PCM continuing as the surviving corporation. PCM will no longer be a public company, its shares will cease to be listed on the Nasdaq and its shares will be deregistered under the Exchange Act. As such, PCM would no longer file periodic reports with the SEC.

Q:    When do you expect the merger to be completed?

A:

Subject to the satisfaction or waiver of the closing conditions described under the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 82 of this proxy statement, including the adoption of the merger agreement by PCM stockholders at the special meeting, PCM and Insight expect that the merger will be completed within five months from the signing of the merger agreement. However, the merger is subject to various regulatory clearances and approvals and other conditions, and it is possible that factors outside the control of

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PCM or Insight could result in the merger being completed at a different time or not at all. See the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 82 of this proxy statement.

Q:    What happens if the conditions to the merger are not satisfied or waived by November 20, 2019?

A:

Under the terms of the merger agreement, if the conditions to the merger are not satisfied or waived by November 20, 2019, which we refer to as the outside date, then either PCM or Insight may terminate the merger agreement, provided that the terminating party has not breached its obligations under the merger agreement in any manner that will have proximately contributed to the occurrence of the failure of a condition to the consummation of the merger. In the event the merger is not completed for any reason, PCM stockholders will not receive any merger consideration for their shares of PCM common stock in connection with the merger. Instead, all PCM stockholders will continue to own their shares of PCM common stock, all PCM stock options and PCM RSUs will continue to vest on their applicable vesting schedules and shares of PCM common stock will continue to be listed on the Nasdaq Global Market.

Q:    How does the per share merger consideration compare to the market price of PCM's common stock prior to announcement of the merger?

A:

The per share merger consideration represents a premium of approximately 43.6% to PCM's closing stock price on June 21, 2019 ($24.38), the last full trading day before the public announcement of the merger.

Q:    Why am I being asked to approve the compensation proposal?

A:

Under SEC rules, we are required to seek a non-binding, advisory vote with respect to the compensation that may be paid or become payable to named executive officers that is based or otherwise relates to the merger, commonly referred to as "golden parachute" compensation.

Q:    What will happen if the stockholders do not approve the compensation proposal at the special meeting?

A:

Approval of the compensation proposal is not a condition to completion of the merger. The vote with respect to the compensation proposal is on an advisory basis and will not be binding on PCM. Therefore, regardless of whether stockholders approve the compensation proposal, if the merger agreement is approved by the stockholders and the merger is completed, the "golden parachute" compensation will be paid or may become payable to PCM's Named Executive Officers to the extent provided in the merger agreement and in our related compensation plans and agreements. Such "golden parachute" compensation is described more fully in the section entitled "The Merger—Interests of PCM's Directors and Executive Officers in the Merger—Golden Parachute Compensation Arrangements", beginning on page 51 of this proxy statement.

About the Special Meeting

Q:    What am I being asked to vote on at the special meeting?

A:

You are being asked to consider and vote on (i) a proposal to adopt the merger agreement, (ii) the compensation proposal and (iii) the adjournment proposal.

Q:    What is the vote required to approve each proposal at the PCM special meeting?

A:

The merger cannot be completed unless PCM stockholders adopt the merger agreement, which requires the affirmative vote at the special meeting of the holders of a majority of the outstanding

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shares of PCM common stock entitled to vote at the special meeting. If you fail to submit a valid proxy or vote in person at the special meeting or abstain, or if your shares of PCM common stock are held through a bank, brokerage firm or other nominee and you do not instruct your bank, brokerage firm or other nominee, as applicable, to vote your shares of PCM common stock, this has the same effect as voting your shares of PCM common stock "AGAINST" the adoption of the merger agreement.

Approval of the compensation proposal requires the affirmative vote of the holders of a majority of the voting power of the shares of PCM common stock represented either in person or by proxy at the special meeting and entitled to vote on the proposal. An abstention has the same effect as a vote "AGAINST" the approval of this proposal. Uninstructed shares have no effect on the outcome of this proposal.

The adjournment proposal requires the affirmative vote of the holders of a majority of the voting power of the shares of PCM common stock represented either in person or by proxy at the special meeting. An abstention has the same effect as a vote "AGAINST" the approval of this proposal, but uninstructed shares will have no effect on the outcome of this proposal.

See the section entitled "Information About the Special Meeting—Vote Required" beginning on page 59 of this proxy statement.

Q:    What constitutes a quorum for the special meeting?

A:

The presence, in person or represented by proxy, of the holders of record of a majority of the issued and outstanding shares of the common stock of PCM entitled to vote at the special meeting constitutes a quorum for the purposes of the special meeting. A quorum is necessary to transact business at the special meeting.

Q:    How does the PCM board of directors recommend that I vote at the special meeting?

A:

The PCM board of directors recommends that PCM stockholders vote " FOR " the proposal to adopt the merger agreement, " FOR " the compensation proposal and " FOR " the adjournment proposal. See the section entitled "The Merger—Recommendation of the PCM Board of Directors; Reasons for the Merger" beginning on page 32 of this proxy statement.

Q:    Do directors and executive officers of PCM have certain interests in the merger that may be different from or in addition to those of PCM stockholders generally?

A:

Yes. Directors and executive officers of PCM have certain interests in the merger that may be different from or in addition to those of PCM stockholders generally. The PCM board was aware of and considered these interests, among other matters, in reaching its decisions to (i) determine that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of PCM stockholders, (ii) approve, adopt and declare advisable the merger agreement and the transactions contemplated thereby, including the merger, (iii) direct that the merger agreement and the merger be submitted to a vote of PCM stockholders and (iv) resolve to recommend the adoption of the merger agreement by PCM stockholders. See the section entitled "The Merger—Interests of PCM's Directors and Executive Officers in the Merger" beginning on page 47 of this proxy statement for a more detailed description of these interests.

Q:    Who can vote at the special meeting?

A:

All holders of record of shares of PCM common stock as of the close of business on July 22, 2019, the record date for the special meeting, which we refer to as the record date, are entitled to receive notice of, and to vote at, the special meeting. On the record date, there were 12,327,791 shares of PCM common stock outstanding and entitled to vote at the special meeting. You will have one vote for each share of PCM common stock that you owned on the record date on all matters properly coming before the special meeting.

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Q:    How do I vote?

A:

If you are a stockholder of record, you may have your shares of PCM common stock voted on the matters to be presented at the special meeting in any of the following ways:

•

over the Internet, by accessing the Internet website specified on the enclosed proxy card. The control number provided on your proxy card is designed to verify your identity when voting by proxy over the Internet. Proxies delivered over the Internet must be submitted by 11:59 p.m. Eastern time on August 25, 2019 to ensure your proxy is voted. Please be aware that if you vote by proxy over the Internet, you may incur costs, such as Internet access charges, for which you will be responsible;

•

by calling the toll-free telephone number shown on the enclosed proxy card (proxies given by telephone must be submitted by 11:59 p.m. Eastern time on August 25, 2019 to ensure your proxy is voted);

•

by completing, signing, dating and returning the enclosed proxy card in the accompanying prepaid reply envelope; or

•

in person—you may attend the special meeting and cast your vote there or by proxy appointed by instrument in writing, executed by you or by your duly authorized attorney-in-fact.

After carefully reading and considering the information contained in this proxy statement, please submit your proxy as soon as possible so that your shares will be represented at the special meeting. Please follow the instructions set forth on the proxy card or, if your shares are held in the name of your bank, brokerage firm or other nominee, on the voting instruction form provided by your bank, brokerage firm or other nominee. Please note that if your shares are held in the name of your bank, brokerage firm or other nominee and you wish to vote in person at the special meeting, you must obtain a legal proxy from your bank, brokerage firm or other nominee.

Q:    What happens if I sell my shares of PCM common stock before the special meeting?

A:

The record date is earlier than both the date of the special meeting and the effective time. If you transfer your shares of PCM common stock after the record date but before the special meeting, you will, unless the transferee requests a proxy from you and each of you notifies PCM in writing of such special arrangements retain your right to vote at the special meeting but will transfer the right to receive the per share merger consideration to the person to whom you transfer your shares. In order to receive the per share merger consideration, you must hold your shares at the effective time.

Q:    Are any PCM stockholders already obligated to vote in favor of the merger?

A:

Yes. On June 23, 2019, concurrently with the execution of the merger agreement, certain stockholders of PCM identified therein, including each of PCM's directors and executive officers and certain affiliated trusts, entered into a voting agreement with Insight, Merger Sub and PCM, which we refer to as the voting agreement, pursuant to and subject to the conditions of which, among other things, each such stockholder (1) agreed to cause to be present and counted and to vote (or cause to be voted or acted upon by written consent with respect to) all of such stockholder's shares of PCM common stock (a) in favor of the adoption of the merger agreement and approval of the transactions contemplated thereby, including the merger, (b) in favor of any proposal to adjourn or postpone any stockholder meeting at which there is a proposal for such stockholders to vote upon the merger agreement, including the special meeting, to a later date if there are not sufficient votes to adopt the merger agreement or if there are not sufficient shares of PCM common stock present in person or by proxy at such meeting to constitute a quorum, (c) against any "acquisition proposal" or "alternative transaction" (in each case, as defined in the

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merger agreement) or the adoption of any agreement providing for or contemplating an "alternative transaction" (as defined in the merger agreement) and (d) against any amendment of PCM's charter or other action or agreement of PCM, in each case, for which the vote of the stockholders is required to authorize such action or agreement, that would (i) reasonably be expected to result in any of the conditions to the consummation of the merger under the merger agreement not being fulfilled, or (ii) reasonably be expected to prevent or materially delay the consummation of the merger and the other transactions contemplated by the merger agreement and (2) appointed Insight, with full power of substitution, as such stockholder's true and lawful attorney in fact and proxy for the purposes of voting such stockholder's shares at any stockholder meeting at which there is a proposal for such stockholder to vote upon the merger agreement, including the special meeting, in order to cause such stockholder to comply with the applicable covenant of the voting agreement. The voting agreement automatically terminates upon the earliest to occur of: (1) the effective time of the merger, (2) termination of the merger agreement pursuant to its terms, (3) the effective date of a written agreement duly executed and delivered by each of the parties to the voting agreement terminating the voting agreement and (4) the amendment of the merger agreement, without the prior written consent of the stockholders party to the voting agreement, that affects the material terms of the merger agreement that is adverse to PCM or its stockholders. As of June 23, 2019, the stockholder parties to the voting agreement owned 2,836,535 shares of PCM common stock, representing approximately 23% of the shares of PCM common stock issued and outstanding at such time. The voting agreement is attached to this proxy statement as Annex B . For a further discussion of the voting agreement, see "Information about the Special Meeting—Voting Agreement" beginning on page 60 of this proxy statement.

Q:    When and where is the special meeting?

A:

The special meeting will be held on August 26, 2019, at 8:00 a.m. Pacific time, at the offices of PCM, 1940 E. Mariposa Avenue, El Segundo, CA 90245. If you are a PCM stockholder on the record date, you may attend the special meeting and vote in person. Please note, however, that if your shares of PCM common stock are held of record by a bank, broker or other nominee and you wish to vote at the special meeting, you must obtain a "legal proxy," executed in your favor from such bank, broker or other nominee who is the holder of record of your shares of PCM common stock in order to vote your shares of PCM common stock in person at the special meeting. For additional information about the special meeting, see the section entitled "Information About the Special Meeting" beginning on page 58 of this proxy statement.

Q:    If my shares of PCM common stock are held in "street name" by my bank, brokerage firm or other nominee, will my bank, brokerage firm or other nominee automatically vote those shares for me?

A:

If your shares are held by a bank, brokerage firm or other nominee, you are considered the beneficial owner of shares held in "street name," and your bank, brokerage firm or other nominee is considered the stockholder of record with respect to those shares. Your bank, brokerage firm or other nominee will send you, as the beneficial owner, a package describing the procedure for voting your shares. You should follow the instructions provided by them to vote your shares. You are invited to attend the special meeting; however, you may not vote shares held in "street name" by your bank, brokerage firm or other nominee in person at the special meeting unless you obtain a "legal proxy" from your bank, brokerage firm or other nominee that holds your shares, giving you the right to vote the shares at the special meeting.

Your bank, brokerage firm or other nominee will only be permitted to vote your shares of PCM common stock if you instruct your bank, brokerage firm or other nominee how to vote. You should follow the procedures provided by your bank, brokerage firm or other nominee regarding the

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voting of your shares of PCM common stock. Under the rules of the New York Stock Exchange, brokerage firms and other nominees who hold shares of PCM common stock in street name for their customers have authority to vote on "routine" proposals when they have not received instructions from beneficial owners. However, banks, brokerage firms and other nominees are precluded from exercising their voting discretion with respect to non-routine matters, such as the adoption of the merger agreement, the compensation proposal and the adjournment proposal. As a result, absent specific instructions from the beneficial owner of such shares, banks, brokerage firms and other nominees are not empowered to vote such shares. Because it is expected that all proposals to be voted on at the special meeting will be non-routine matters, banks, brokerage firms and other nominees will not have discretionary authority to vote on any matter at the meeting. If you do not provide instructions to your bank, brokerage firm or other nominee, your shares will not be counted as present at the meeting. Thus, the effect of not instructing your bank, broker or other nominee how you wish your shares to be voted will be the same as voting your shares "AGAINST" the adoption of the merger agreement but will have no effect on the compensation proposal and will have no effect on the adjournment proposal.

Q:    How many votes do I have?

A:

Each PCM stockholder is entitled to one vote for each share of PCM common stock held of record as of the record date. As of the close of business on the record date, there were 12,327,791 outstanding shares of PCM common stock.

Q:    If a stockholder gives a proxy, how are the shares of PCM common stock voted?

A:

Regardless of the method by which you choose to vote, the individuals named on the enclosed proxy card will vote your shares of PCM common stock in the way that you indicate. When completing the Internet process or the proxy card, you may specify whether your shares of PCM common stock should be voted " FOR " or " AGAINST " or to " ABSTAIN " from voting on all, some or none of the specific items of business to come before the special meeting.

Q:    What will happen if I sign and return my proxy or voting instruction card without indicating how to vote?

A:

If you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal, the PCM common stock represented by your proxy will be voted "FOR" the adoption of the merger agreement, "FOR" the compensation proposal and "FOR" the adjournment proposal.

Q:    Can I change my vote after I have delivered my proxy or voting instruction card?

A:

Yes. Any stockholder giving a proxy has the power to revoke it at any time before it is exercised. PCM stockholders of record may revoke their proxy by signing, dating and returning a duly executed proxy bearing a later date (including by means of an Internet or telephone vote) or filing an instrument of revocation with PCM's Corporate Secretary at PCM, Inc., Attention: Office of the Secretary, 1940 E. Mariposa Avenue, El Segundo, CA 90245. Stockholders of record may also revoke a proxy by attending the special meeting and voting in person. Attendance at the special meeting alone will not revoke any proxy. If not revoked, the proxy will be voted at the special meeting in accordance with your instructions.

If your shares are held in an account at a bank, brokerage firm or other nominee and you have delivered your voting instruction card to your broker, bank or other nominee, you should contact your bank, brokerage firm or other nominee to change your vote.

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Q:    What should I do if I receive more than one set of voting materials?

A:

If you hold shares of PCM common stock in "street name" and also directly as a record holder or otherwise or if you hold shares of PCM common stock in more than one brokerage account, you may receive more than one set of voting materials relating to the special meeting. Please complete, sign, date and return each proxy card (or cast your vote by Internet or telephone as provided on your proxy card) in order to ensure that all of your shares of PCM common stock are voted. If you hold your shares in "street name" through a bank, brokerage firm or other nominee, you should follow the procedures provided by your bank, brokerage firm or other nominee to vote your shares.

Q:    If I hold physical certificates representing my shares of PCM common stock, should I send in my certificates now?

A:

No, please do NOT return your certificate(s) with your proxy. If the merger agreement is adopted by PCM stockholders and the merger is completed, and if you hold physical certificates, you will be sent a letter of transmittal promptly after the effective time describing how you may exchange your shares of PCM common stock for the per share merger consideration.

Q:    Where can I find the voting results of the special meeting?

A:

The preliminary voting results will be announced at the special meeting. In addition, within four business days following certification of the final voting results, PCM intends to file the final voting results with the SEC on a Current Report on Form 8-K.

Q:    Who can help answer any other questions I have?

A:

If you have additional questions about the merger, need assistance in submitting your proxy or voting your shares of PCM common stock, or need additional copies of this proxy statement or the enclosed proxy card, please contact The Proxy Advisory Group, LLC, PCM's proxy solicitor, at (212) 616-2180.

Q:    Who can attend the special meeting?

A:

If you are a PCM stockholder on the record date, you may attend the special meeting and vote in person. All attendees will be required to provide a government-issued, current form of photo identification. Please note, however, that if your shares of PCM common stock are held of record by a bank, broker or other nominee and you wish to vote at the special meeting, you must obtain a "legal proxy," executed in your favor from such bank, broker or other nominee who is the holder of record of your shares of PCM common stock in order to vote your shares of PCM common stock in person at the special meeting.

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THE MERGER

        This section describes the merger. The description in this section and elsewhere in this proxy statement is qualified in its entirety by reference to the complete text of the merger agreement, a copy of which is attached as Annex A and is incorporated by reference into this proxy statement. This summary does not purport to be complete and may not contain all the information about the merger that is important to you. You are encouraged to read the merger agreement carefully and in its entirety.

Merger Consideration

        Upon completion of the merger, at the effective time, by virtue of the merger and without any action on the part of PCM, Insight, Merger Sub or the holders of any shares of PCM common stock or any shares of Merger Sub common stock, each share of PCM common stock issued and outstanding immediately prior to the effective time (other than excluded shares) will be automatically canceled and converted into the right to receive $35.00 per share in cash, without interest and less any applicable withholding taxes, which we refer to as the per share merger consideration. Excluded shares are (i) shares of PCM common stock owned by Insight, Merger Sub or any other direct or indirect wholly-owned subsidiary of Insight and shares of PCM common stock owned by PCM or any direct or indirect wholly-owned subsidiary of PCM, and in each case not held on behalf of third parties, and (ii) shares of PCM common stock that are owned by stockholders of PCM who have perfected and not withdrawn a demand for appraisal rights pursuant to Section 262 of the DGCL.

        After the merger is completed, you will have the right to receive the per share merger consideration, but you will no longer have any rights as a PCM stockholder. PCM stockholders will receive the per share merger consideration after exchanging their PCM stock certificates or book entry shares in accordance with the instructions contained in the letter of transmittal to be sent to all PCM stockholders promptly after the effective time of the merger.

PCM Stock Options

        Each PCM stock option, whether vested or unvested, that is outstanding and unexercised immediately prior to the effective time will be, automatically and without any action on the part of the holder, deemed to be vested, cancelled and only entitle the holder of such stock option to receive (without interest and less any applicable withholding taxes), at or as soon as reasonably practicable after the effective time, an amount in cash equal to the product of (i) the number of unexercised shares subject to such stock option immediately prior to the effective time multiplied by (ii) the excess of (A) the per share merger consideration over (B) the exercise price per share of such stock option. For purposes of this calculation, the vesting of any stock option subject to performance conditions will be fully accelerated and deemed achieved contingent and effective upon the closing of the merger.

        See the section entitled "The Merger Agreement—Treatment of PCM Stock Options" beginning on page 66 of this proxy statement.

PCM Restricted Stock Units (RSUs)

        Each outstanding PCM RSU, whether vested or unvested, that is outstanding immediately prior to the effective time will be, automatically and without any action on the part of the holder, deemed to be vested, cancelled and only entitle the holder of such PCM RSU to receive (without interest and less any applicable withholding taxes), at or as soon as reasonably practicable after the effective time, an amount in cash equal to the per share merger consideration plus any accrued and unpaid dividend equivalents with respect to such PCM RSU.

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        See the section entitled "The Merger Agreement—Treatment of PCM Restricted Stock Units (RSUs)" beginning on page 66 of this proxy statement.

Effects of the Merger

        If the conditions to closing the merger are satisfied or waived (to the extent waiver is permitted by applicable law) and the merger is completed, Merger Sub will be merged with and into PCM, with PCM continuing as the surviving corporation and a wholly-owned subsidiary of Insight.

        If the merger is completed, PCM's stockholders will have the right to receive, in exchange for each share of PCM common stock that they own immediately prior to the effective time of the merger, other than excluded shares, $35.00 per share in cash, without interest and less any applicable withholding taxes.

        Following the merger, PCM's stockholders will not own any shares of capital stock of PCM and, accordingly, will cease to have any rights as a stockholder of PCM other than to receive the per share merger consideration to which such stockholder is entitled or, if applicable, rights to appraisal under the DGCL.

        Shares of PCM common stock are listed on Nasdaq under the symbol "PCMI." If the merger is completed, PCM will no longer be a public company, its shares will cease to be listed on Nasdaq and it will no longer file periodic and other reports and statements with the SEC. Following the merger, PCM will be a subsidiary of Insight, which is a public company and subject to the above-described disclosure requirements and other rules and regulations of the SEC. In addition, following consummation of the merger, the reporting obligations under Section 16 of the Exchange Act for PCM's directors, officers and principal stockholders, in their capacities as such, will cease but will, if they are or become directors, officers or principal stockholders of Insight, continue with respect to Insight.

        For information regarding the material United States federal income tax consequences of the merger, see the section entitled "Material U.S. Federal Income Tax Consequences of the Merger for U.S. Holders" beginning on page 87 of this proxy statement.

Effect on PCM if the Merger Is Not Completed

        If the merger agreement proposal is not approved by PCM's stockholders or if the merger is not completed for any other reason, PCM stockholders will not receive any payment for their shares of common stock. Instead, PCM will remain an independent public company, its common stock will continue to be listed and traded on Nasdaq and registered under the Exchange Act and PCM will continue to file periodic reports with the SEC. In addition, if the merger is not completed, PCM expects that management will operate the business in a manner similar to that in which it is being operated today and that PCM stockholders will continue to be subject to the same risks and opportunities to which they are currently subject.

        Furthermore, if the merger is not completed, and depending on the circumstances that would have caused the merger not to be completed, it is likely that the price of PCM's common stock will decline significantly. If that were to occur, it is uncertain when, if ever, the price of our common stock would return to the price at which it traded as of the date of this proxy statement.

        Accordingly, if the merger is not completed, there can be no assurance as to the effect of these risks and opportunities on the future value of your shares of our common stock. If the merger is not completed, the PCM board of directors will continue to evaluate and review our business operations, properties and capitalization, among other things, make such changes as are deemed appropriate and continue to seek to identify strategic alternatives to enhance stockholder value. If the merger agreement proposal is not approved by PCM stockholders or if the merger is not completed for any

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other reason, there can be no assurance that any other transaction acceptable to PCM will be offered or that our business, prospects or results of operation will not be adversely impacted.

        In addition, under specified circumstances, PCM will be required to pay Insight a termination fee upon the termination of the merger agreement, as described in the sections entitled "The Merger Agreement—Effect of Termination; Termination Fee" beginning on page 85 of this proxy statement.

Background of the Merger

        The PCM board of directors, with the assistance of management, has periodically reviewed and assessed PCM's business strategy and the various trends and conditions affecting the information technology reseller and services industry generally and PCM specifically. PCM's board of directors has explored a variety of strategic alternatives with the goal of increasing revenues and profitability and maximizing stockholder value.

        In July 2017, Kenneth Lamneck, Insight's President and Chief Executive Officer, reached out to Frank Khulusi, PCM's Chairman and Chief Executive Officer, to explore whether any opportunity existed to discuss a strategic transaction. On July 24, 2017, PCM's board of directors met and authorized PCM to enter into a non-disclosure and standstill agreement with Insight, which the parties entered into on or about August 17, 2017. Messrs. Lamneck and Khulusi met on August 17, 2017 and members of the respective management teams met for high-level discussions on August 18, 2017, which discussions terminated later in August 2017.

        Mr. Lamneck again reached out to Mr. Khulusi in July 2018 to discuss whether there might be an opportunity or interest to discuss a potential strategic transaction.

        On July 23, 2018, PCM's board of directors met and authorized PCM to enter into a new non-disclosure and standstill agreement with Insight, which we refer to as the Insight NDA. Insight and PCM executed the Insight NDA later that day.

        On August 6, 2018, management teams from Insight and PCM met to discuss a potential acquisition of PCM by Insight. On August 28, 2018, Mr. Lamneck called Mr. Khulusi to seek Mr. Khulusi's reaction to a potential acquisition of PCM by Insight for consideration of cash and Insight common stock with an aggregate value of $25.00 per share of PCM common stock, representing a premium of 11% to PCM's closing share price of $22.55 on such date and a premium of 36% to PCM's average closing share price of $18.39 over the prior 90 days. Mr. Khulusi responded that he believed that the PCM board of directors would be expecting a higher indicative price.

        In September, 2018, a representative of B. Riley FBR, Inc., which we refer to as B. Riley, called Glynis Bryan, Insight's Chief Financial Officer, and encouraged Insight to indicate interest at a price per share in the mid to high $30's.

        In early October, 2018, Mr. Khulusi engaged with Mr. Lamneck in an effort to encourage Insight to indicate interest at a price per share above the $25.00 that Mr. Lamneck had discussed on August 6, 2018.

        On October 23, 2018, PCM provided to Insight projections prepared by PCM's management for PCM's 2019, 2020 and 2021 fiscal years.

        On or about November 16, 2018, Ms. Bryan spoke with a representative of B. Riley regarding financial analysis that would support a higher price for PCM. Between November 16 and November 20, 2018, a representative of B. Riley contacted Ms. Bryan several times to encourage Insight to indicate interest at a price per share above $25.00.

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        On or about November 21, 2018, Ms. Bryan called a representative of B. Riley to seek his reaction to a potential acquisition of PCM by Insight for consideration of no less than $30.00 per share of PCM common stock. The B. Riley representative informed Mr. Khulusi, and Mr. Khulusi called a meeting of the PCM board of directors to discuss.

        On November 23, 2018, the PCM board of directors met. Representatives of Sheppard, Mullin, Richter & Hampton LLP, which we refer to as Sheppard Mullin, and a representative of Morris, Nichols, Arsht & Tunnell LLP, which we refer to as Morris Nichols, advised the PCM board of directors concerning fiduciary duties associated with a potential sale of PCM.

        On November 26, 2018, Insight sent PCM a proposal to acquire all of the outstanding shares of PCM for $30.00 per share in cash, which represented a premium of 76% to PCM's closing share price of $17.02 on that date and a premium of 56% to PCM's average closing share price of $19.25 over the prior 90 days. The proposal was contingent on PCM agreeing to a 45-day period of exclusivity with Insight and to Mr. Khulusi and other key leaders entering into non-competition, non-solicitation and voting agreements. The proposal was not subject to a financing contingency.

        On November 29, 2018, the PCM board of directors met to discuss Insight's proposal and exclusivity requirement. The PCM board of directors received a presentation from B. Riley concerning its qualifications, and authorized PCM management to negotiate the terms of an engagement agreement with B. Riley for approval by the PCM board of directors.

        On December 3, 2018, the PCM board of directors met and continued discussion on Insight's proposal and exclusivity requirement. Representatives of B. Riley were invited to the meeting to present on the firm's qualifications to serve as PCM's financial advisor, which qualifications included providing informal advice to PCM's management on prior communications with Insight. The representatives indicated they had no known conflicts of interest with Insight. The PCM board of directors authorized the retention of B. Riley as PCM's financial advisor. At such meeting, the representatives of B. Riley presented preliminary valuation analyses for PCM which included, a preliminary selected precedent transaction analysis, a preliminary selected public company trading comparables analysis, a preliminary discounted cash flow analysis, a preliminary premiums paid analysis, and a statement of then applicable equity research analyst price targets. The discounted cash flow analysis used the projections that PCM's management had provided to Insight on October 23, 2018, for the 2019, 2020 and 2021 fiscal years and included projections for 2022 and 2023 fiscal years prepared by B. Riley with the authorization of PCM management using the assumptions and methodology described under "The Merger—Opinion of Financial Advisor" beginning on page 36. For each of these preliminary analyses other than the discounted cash flow analysis, the $30.00 per share price of Insight's proposal exceeded the upper end of the preliminary share price range implied from such analysis and presented by B. Riley. For the preliminary discounted cash flow analysis, the lower end of the implied share price range was above the $30.00 per share price of Insight's proposal. The PCM board of directors authorized Mr. Khulusi and B. Riley to attempt to negotiate a higher per share price and shorter exclusivity period.

        Between December 3 and December 19, 2018, a representative of B. Riley and Ms. Bryan had a number of discussions about Insight's proposal, including the per share price of that proposal, and next steps.

        On December 19, 2018, Insight sent PCM a letter indicating that it would revise its proposal to increase the per share price to $31.00, and that such price reflected its best and final offer. Insight also indicated that the proposal was contingent on PCM agreeing to a 60-day exclusivity period in connection with the revised proposal. The $31.00 price per share represented a premium of 75% to PCM's closing share price of $17.73 on that date and a premium of 68% to PCM's average closing share price of $18.49 over the prior 90 days.

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        On December 24, 2018, the PCM board of directors met to discuss Insight's revised proposal and exclusivity requirement. The PCM board of directors discussed with its legal and financial advisors the potential benefits and risk of conducting a pre-exclusivity market check. Noting that Insight's proposal reflected a premium of 98% over the closing price of PCM stock on Nasdaq of $15.63 on December 21, 2018 (and a premium of 68% to PCM's average closing share price of $18.40 over the prior 90 days) and believing that a pre-exclusivity market check presented a low likelihood of producing a bidder willing to transact at a higher premium and would present a significant risk of Insight withdrawing from negotiations, the PCM board of directors determined to continue negotiations with Insight on an exclusive basis. The PCM board of directors instructed PCM's management and PCM's financial and legal advisors to negotiate with Insight to attempt to obtain an increase in the $31.00 price per share, a reduction of the exclusivity period to 30 days and an express indication that the ultimate merger agreement would include a "go shop" provision so as to permit PCM to contact potential bidders after the execution of a merger agreement, with a reduced termination fee applicable to bidders that express interest during the "go shop" period. The PCM board of directors instructed Mr. Khulusi not to enter into negotiations with Insight on non-competition, non-solicitation and voting agreements without board approval and further instructed that negotiation of those documents would be handled through PCM's counsel and with the oversight of the PCM board of directors.

        From January 2, 2019 through January 24, 2019, the parties negotiated the terms of Insight's revised proposal and proposed exclusivity agreement. Insight was unwilling to increase the price per share of its revised proposal above $31.00. The revised proposal remained not subject to financing contingency. Negotiations on other issues included the length of the exclusivity period, which ultimately was agreed at 45 days, and following Insight's indication that it would not increase the per share price to higher than $31.00, the treatment of PCM's outstanding in-the-money equity awards that were not already subject to accelerated vesting on change of control. Insight ultimately agreed that such awards would be accelerated upon a closing. Insight would not agree to the inclusion of a "go shop" provision in the ultimate merger agreement. The revised proposal did not address non-competition, non-solicitation or voting agreements.

        On January 24, 2019, the PCM board of directors approved entry into the 45-day exclusivity agreement on the basis of a revised Insight proposal reflecting negotiations through such date.

        On January 25, 2019, Insight delivered its revised proposal reflecting prior negotiations and Insight and PCM entered into the exclusivity agreement.

        On February 4, 2019, PCM opened an electronic data room to Insight and Insight commenced its due diligence review on PCM.

        On February 6, 2019, PCM announced its financial results for the fourth quarter of 2018 and full year of 2018.

        On February 8, 2019, counsel for Insight, Sullivan & Cromwell LLP, sent a draft of the merger agreement to Sheppard Mullin.

        On February 12, 2019, PCM's common stock closed at $30.77 on Nasdaq. Around that time, B. Riley made numerous contacts with Ms. Bryan to encourage Insight to increase the price per share of its proposal.

        On February 13, 2019, Mr. Lamneck called Mr. Khulusi to advise him that Insight would revise its proposal to increase the price per share to $34.00.

        On February 13, 2019, representatives of B. Riley delivered to a representatives of Insight a list of discussion points on the merger agreement prepared by Sheppard Mullin, which included, among other things, the amount of merger consideration in light of PCM's then current stock price, a proposed reduction in the termination fee set forth in the merger agreement from 3.75% to 2.5%, and a

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proposed clarification regarding entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight.

        On February 14, 2019, Sam Cowley, Insight's Senior Vice President, General Counsel and Corporate Secretary, and Robert Newton, PCM's Chief Legal Officer, along with Insight's and PCM's regular outside litigation counsel, discussed due diligence matters, including litigation matters disclosed in PCM's public filings. Insight continued to diligence PCM's outstanding litigation matters through early March through phone conversations and via e-mail exchanges with Mr. Newton and PCM's outside litigation counsel.

        On or about March 1, 2019, Mr. Khulusi called Mr. Lamneck and requested that Insight revise its proposal to increase the price per share to $36.00. Around that time, a representative of B. Riley also called Ms. Bryan to encourage Insight to increase the price per share of its proposal.

        On March 7, 2019, Insight indicated that it would revise its proposal to increase the price per share to $35.00, which represented a premium of 11% to PCM's closing stock price of $31.54 on such date and a premium of 50% to PCM's average closing share price of $23.40 over the prior 90 days. Insight also responded to PCM's February 13, 2019 list of discussion points, indicating that Insight would not agree to a "go-shop" provision, requiring a 3.5% termination fee, and requiring certain amendments to PCM's indemnification agreements with its directors and officers to eliminate the requirement that a purchaser of PCM, in certain circumstances, establish a trust for the benefit of officers and directors to satisfy potential indemnification claims. Insight also declined at that time to provide the proposed clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight.

        On March 9, 2019, Sullivan & Cromwell sent a revised draft of the merger agreement to Sheppard Mullin, which provided for merger consideration of $35.00 per share and included changes to the representations and warranties and covenants, reduced the termination fee from 3.75% to 3.5% and eliminated the reference contained in the initial draft merger agreement to a non-competition agreement applicable to Mr. Khulusi, among other things.

        On March 11, 2019, Insight's 45-day exclusivity period ended.

        On March 12, 2019, PCM provided to Insight revised projections prepared by PCM's management for PCM's 2019 fiscal year and subsequently indicated to Insight that PCM's management had not updated projections for fiscal years 2020 and 2021.

        On March 13, 2019, the PCM board of directors met to discuss the increase in Insight's proposal price to $35.00 per share and the expiration of Insight's exclusivity period. A representative of B. Riley present at the meeting presented an updated preliminary valuation analysis. The PCM board of directors noted that PCM's common stock has a history of volatility, which has at times been uncorrelated with PCM's financial performance. The PCM board of directors further noted that the twelve month price targets of the two recognized equity research analysts covering PCM were $29.60 and $32.50. The B. Riley representative discussed that Insight appeared to have the borrowing capacity necessary to obtain the financing it would need to pay $35.00 per share. At such meeting, representatives of Sheppard Mullin summarized material open issues in the merger agreement, including the 3.5% termination fee proposed by Insight and the previously requested clarification regarding entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight.

        At the same meeting, the PCM board of directors deliberated whether to conduct a market check of Insight's proposal in light of the March 11, 2019 expiration of Insight's exclusivity period. The PCM board of directors considered the benefits of a market check, including the possibility of receiving a proposal with a higher value to PCM's stockholders than Insight's proposal, which might have been more likely than prior to the start of the exclusivity period due to the lower premium represented by

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Insight's proposal at March 11, 2019, or if no such higher proposal was received, validation of the Board's continuing belief in the low likelihood of receiving a more favorable proposal. The PCM board also considered the risk of a market check, including that Insight would discontinue pursuing a transaction involving competitive bidding and potential adverse effects on PCM personnel and customers should information concerning the market check not remain confidential despite PCM's best efforts. The PCM board of directors determined to authorize Mr. Khulusi to request that B. Riley actively seek other interested bidders in categories to be determined by PCM management and B. Riley. The PCM board of directors also instructed Sheppard Mullin to provide comments to Insight's last draft of the merger agreement.

        On March 13, 2019, Sheppard Mullin sent a revised draft of the merger agreement to Sullivan & Cromwell, which reserved on the 3.5% termination fee proposed by PCM and included the previously requested clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight.

        On March 18, 2019, B. Riley began contacting other potential bidders. Also on March 18, 2019, representatives of Insight provided to representatives of PCM a list of threshold issues that Insight indicated must be resolved prior to proceeding with further work on the draft merger agreement and the transaction in general, including reaching a basic understanding regarding the level of detail for certain PCM representations and warranties and certain pre-closing operating restrictions on PCM.

        On March 19, 2019, Messrs. Cowley and Newton discussed merger agreement issues, including each party's position on certain representations and warranties and pre-closing operating restrictions on PCM contained in the draft merger agreement. Mr. Cowley and Mr. Newton agreed to recommend to the parties that they should continue discussions and negotiations related to these issues.

        On March 19, 2019, PCM's common stock closed at $36.07 on Nasdaq.

        On March 20, 2019, the PCM board of directors met and discussed the status of negotiations with Insight in light of the increased trading price of PCM's common stock, the status of negotiation of other significant merger agreement issues and the status of the market check that it authorized on March 13, 2019. Following discussion, the PCM board of directors authorized Mr. Khulusi to continue discussions with Insight concerning the merger consideration and other significant merger agreement issues. The PCM board of directors further instructed B. Riley to continue its market check process.

        On March 21, 2019, Sullivan & Cromwell sent a revised draft of the merger agreement to Sheppard Mullin, which provided for merger consideration of $35.00 per share of PCM common stock.

        On March 25, 2019, Mr. Khulusi spoke to Insight's senior leadership team about PCM's view of the 3.5% termination fee, PCM's insistence on the clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight and Insight's proposal of $35.00 per share compared to current trading prices, which remained above $35.00 per share. Insight's senior leadership team indicated that Insight was unwilling to increase the per share price in its proposal to at or above the then current trading level.

        Later in the day on March 25, 2019, the PCM board of directors met and discussed the status of negotiations with Insight. Mr. Khulusi reported on his conversation with Insight's senior leadership team earlier in the day. The PCM board of directors expressed its sense that notwithstanding the recent trading activity in PCM's stock, $35.00 per share might represent a fair price to PCM stockholders and further noted the history of volatility in PCM's common stock price. However, the directors acknowledged that notwithstanding these factors, it might be challenging to complete a transaction at a price below the trading price prevailing at the date of entry into the merger agreement. The PCM board of directors then discussed issues with the merger agreement that continued to remain open in the most recent draft, including the 3.5% proposed termination fee and the requested clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger

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agreement by Insight (rejected by Insight in the March 21 draft of the merger agreement). At such meeting, a representative of B. Riley updated the PCM board of directors concerning the status of contacts with other potential bidders. Such representative advised the PCM board of directors that 13 potential strategic bidders were contacted, 4 parties had passed for a variety of reasons and 9 parties had engaged at various levels in discussions. One party had executed a non-disclosure agreement and 4 additional non-disclosure agreements were in negotiation. All standstill provisions contained in non-disclosure agreements entered into with interested bidders provided for the termination of such provisions upon PCM's entry into a written agreement with respect to a transaction involving transfer of majority control of PCM or all or substantially all of PCM's assets. The PCM board then discussed processes and costs for continuing negotiation with Insight and instructed Sheppard Mullin to provide comments to Insight's last draft of the merger agreement.

        On March 25, 2019, Sheppard Mullin sent a revised draft of the merger agreement to Sullivan & Cromwell, which, among other things, reserved on the amount of merger consideration (in light of PCM's then current stock price), included the clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight and proposed a termination fee of 2.9%.

        On March 26, 2019, B. Riley expanded its market check to financial sponsors, with the concurrence of Mr. Khulusi in accordance with the prior authorization of the PCM board of directors. On March 26, 2019, PCM's common stock closed at $37.10 on Nasdaq.

        On March 27, 2019, Insight's senior leadership team advised Mr. Khulusi that the parties were reasonably close on the merger agreement, but Insight would terminate any further negotiation discussions as a result of PCM's stock trading price being higher than the $35.00 price per share at which Insight was willing to transact.

        On March 28, 2019, the PCM board of directors met. Mr. Khulusi advised the directors of Insight's decision to terminate negotiations. At such meeting, a representative of B. Riley updated the board concerning the status of contacts with other potential bidders. The PCM board of directors indicated its openness to restarting negotiations with Insight and instructed management and B. Riley to continue its market check.

        On April 16, 2019, Strategic Bidder A submitted a non-binding indication of interest, indicating a total enterprise value range of $550 million to $650 million, implying a per share purchase price range of $33.00 to $40.00, which indication of interest was subject to, among other things, their due diligence review. PCM's common stock closed that date at $31.33 per share on Nasdaq.

        On April 25, 2019, PCM announced its first quarter 2019 results. PCM's common stock closed that day at $27.55 per share on Nasdaq.

        On April 29, 2019, PCM management presented to representatives from Strategic Bidder A, including a financial overview and discussions of PCM's business model, market strategy and competitive position.

        On April 30, 2019, Financial Bidder A submitted a non-binding indication of interest at a range of $28.75 to $31.50 per share of PCM common stock.

        Between April 29 and May 1, 2019, a representative of B. Riley engaged in conversations with Ms. Bryan to encourage Insight to restart negotiations.

        On May 2, 2019, Brandon LaVerne, PCM's Chief Financial Officer, spoke to the chief financial officer of Strategic Bidder A to respond to follow-up questions from Strategic Bidder A resulting from the April 29, 2019 management presentation.

        On May 6, 2019, PCM's common stock closed at $30.00 per share on Nasdaq.

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        On May 6, 2019, Mr. Lamneck called Mr. Khulusi to indicate that Insight wished to reengage in discussion towards a transaction and reiterated its interest at a price of $35.00 per share of PCM common stock, representing a premium of 17% to PCM's closing price of $30.00 per share on that date and a premium of 7% to PCM's average closing share price of $32.56 over the prior 90 days.

        On May 7, 2019, the PCM board of directors met to discuss Insight's renewed interest in a transaction at the $35.00 price per share. A representative of B. Riley updated the board of directors concerning the market check. Since receiving authorization to contact other potential bidders on March 13, 2019, B. Riley had contacted 27 parties, including 9 financial sponsors and 18 strategic parties, and received indications of interest from Strategic Bidder A and Financial Bidder A. Twenty-three of the parties B. Riley contacted passed on the opportunity to explore a potential transaction with PCM and two others had not passed but were not actively moving forward. The B. Riley representative indicated that Strategic Bidder A had stalled in its evaluation process, as indicated by its lack of response to communications from B. Riley after May 2, 2019. The B. Riley representative indicated that Financial Bidder A's indicated price range was below Insight's $35.00 per share proposal, and Financial Bidder A had not shown a willingness to increase its indicated price range. The PCM board of directors instructed management and the legal and financial advisors to resume negotiations with Insight towards a merger agreement that could be submitted to the PCM board of directors for approval and also to continue efforts to engage with Strategic Bidder A, Financial Bidder A and any other contacted potential bidders that remained engaged in pursuing the opportunity. PCM proceeded to reactivate Insight's credentials for the electronic data room.

        On May 7, 2019, Insight provided to PCM a revised draft of the merger agreement, a form of voting agreement and a form of amendment and waiver of indemnification agreement for PCM's directors and officers.

        On May 8, 2019, the PCM board of directors met to discuss the status of the merger agreement and related issues. The PCM board of directors then discussed issues with the merger agreement that continued to remain open in Insight's most recent draft, including the 3.5% proposed termination fee and the proposed clarification regarding entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight. The PCM board of directors determined to accept the 3.5% termination fee, taking into account the status of the market check that was being performed by B. Riley. The PCM board of directors instructed Sheppard Mullin to provide Sullivan & Cromwell with a list of discussion points on the merger agreement draft received May 7, 2019 to resolve all open points in the merger agreement as part of a package deal.

        On May 8, 2019, Sheppard Mullin sent a list of discussion points on the merger agreement to Sullivan & Cromwell, which, among other things, provided for merger consideration of $35.00 per share, agreed to the 3.5% termination fee and included the proposed clarification regarding entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight.

        On May 9, 2019, Sullivan & Cromwell sent a revised draft of the form of amendment and waiver of indemnification agreement to Sheppard Mullin.

        On May 10, 2019, Sullivan & Cromwell sent responses to Sheppard Mullin's list of discussion points on the merger agreement and a revised draft of the portion of the merger agreement addressing interim operating covenants.

        From May 11, 2019 to May 17, 2019, Sheppard Mullin and Sullivan & Cromwell exchanged multiple revised drafts of the merger agreement, voting agreement and amendment and waiver of indemnification agreement.

        On May 16, 2019, senior management of PCM and Insight and representatives of Sheppard Mullin and Sullivan & Cromwell discussed the remaining open issues on the merger agreement.

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        On May 17, 2019, the PCM board of directors met. Representative of B. Riley presented an updated preliminary valuation analysis and updated the directors on the market check. Of the 27 potential bidders contacted by B. Riley, 24 had formally passed on the opportunity. One financial sponsor had not yet agreed to the terms of a non-disclosure agreement. The B. Riley representative advised that Financial Bidder A remained interested but was unwilling to increase its price range and that Strategic Bidder A had not responded to multiple inquiries made between May 3, 2019 and May 17, 2019. The PCM board of directors also received an update on the status of merger agreement negotiations with Insight.

        Later in the day on May 17, 2019, the parties agreed to resolution of remaining open issues under the merger agreement and the amendment and waiver of indemnification agreement, including the clarification regarding PCM's entitlement to seek certain remedies in the event of a breach of the merger agreement by Insight. The $35.00 per share price proposed by Insight represented a premium of 24% to PCM's closing price of $28.14 per share on that date and a premium of 8% to PCM's average closing share price of $32.37 over the prior 90 days.

        Between May 17, 2019 and June 19, 2019, Insight continued to conduct due diligence and PCM, Insight and their respective counsel continued to negotiate the merger agreement disclosure schedules.

        On June 19, 2019, the PCM board of directors met and received an update from management and from Sheppard Mullin on the status of due diligence and the timeline to execution of a definitive agreement. The $35.00 per share price proposed by Insight represented a premium of 39% to PCM's closing price of $25.17 per share on that date and a premium of 17% to PCM's average closing share price of $29.89 over the prior 90 days.

        Between June 19, 2019 and June 23, 2019, Sheppard Mullin and Sullivan & Cromwell worked to finalize the merger agreement and the disclosure schedules and each of the voting agreement and the first amendment to indemnification agreement, waiver and release, which we refer to as the ancillary agreements, for execution.

        On June 23, 2019, the PCM board of directors met with representatives of B. Riley, Sheppard Mullin and Morris Nichols, to review the terms of the merger agreement and the ancillary agreements, and to consider the approval of the transactions contemplated thereby. Representatives of Sheppard Mullin discussed, among other things, the terms of the merger agreement and the ancillary agreements. Representatives of B. Riley reviewed the results of the market check performed at the instruction of the PCM board of directors and confirmed that since May 17, 2019, Strategic Bidder A remained non-responsive and Financial Bidder A remained unwilling to increase its indicated price range, and no other contacted party had made any attempt to resume communications with B. Riley on a potential transaction with PCM. Representatives of B. Riley then reviewed B. Riley's valuation analyses. See "The Merger—Opinion of Financial Advisor" beginning on page 36 for a discussion of the valuation analysis used by B. Riley and presented to the PCM board of directors. Following discussion, at the request of the PCM board of directors, B. Riley rendered an oral opinion to the PCM board of directors (which was confirmed by delivery of a written opinion, dated June 23, 2019, to the PCM board of directors) to the effect that, as of such date and based upon and subject to the various assumptions made, procedures followed, matters considered and limitations and qualifications set forth therein, the merger consideration in connection with the transaction is fair to PCM's stockholders from a financial point of view. The $35.00 per share price represented a premium of 44% to PCM's closing price of $24.38 per share on that date and a premium of 18% to PCM's average closing share price of $29.64 over the prior 90 days.

        Following further discussion and consideration, including with respect to the reasons for the merger detailed under "The Merger—Recommendation of the PCM Board of Directors; Reasons for the Merger" below, the PCM board of directors unanimously adopted resolutions determining that the merger agreement and the merger and the other transactions contemplated by the merger agreement

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and the ancillary agreements are fair, advisable and in the best interests of PCM and its stockholders and that the merger, the merger agreement and the transactions contemplated by the merger agreement and the ancillary agreements are declared advisable, adopted and approved. The PCM board of directors further directed that the merger agreement be submitted for adoption by PCM's stockholders at a meeting of such stockholders and recommended that such stockholders adopt the merger agreement.

        Later in the day on June 23, 2019, the merger agreement and ancillary agreements were executed by the parties to those agreements, and early in the morning on June 24, 2019, the transaction was publicly announced.

Recommendation of the PCM Board of Directors; Reasons for the Merger

        On June 23, 2019, the PCM board of directors unanimously (i) determined that the merger agreement and the merger and the other transactions contemplated by the merger agreement and the ancillary agreements, are fair, advisable and in the best interests of PCM and its stockholders, (ii) declared advisable, adopted and approved the merger agreement, the merger and the other transactions contemplated by the merger agreement and the ancillary agreements and (iii) directed that the merger agreement be submitted for adoption by PCM's stockholders at a meeting of such stockholders and recommended that such stockholders adopt the merger agreement. Under the resolutions adopted by the PCM board of directors, "ancillary agreements" means the voting agreement, the first amendment to indemnification agreement, waiver and release (required to be signed by PCM's directors and officers in connection with the merger agreement) and the exhibits and schedules to such documents.

        In evaluating the merger agreement, the merger and the other transactions contemplated by the merger agreement, the PCM board of directors consulted with PCM's executive management, outside legal counsel and outside financial advisor. In recommending that the PCM stockholders vote their shares of common stock in favor of the proposal to adopt the merger agreement, the PCM board of directors also considered a number of factors potentially weighing in favor of the merger, including the following (not necessarily in order of relative importance):

•

The belief of the PCM board of directors, after a review of PCM's current and historical financial condition, results of operations, prospects, business strategy, competitive position and industry, including the potential impact (which cannot be quantified numerically) of those factors on the trading price of PCM common stock, that the value offered under the merger agreement is more favorable to PCM stockholders than the potential value that might have resulted from remaining an independent public company, considering:



•

The uncertain and volatile demand in the enterprise-class IT services and solutions market;



•

Rapidly changing technologies in the IT services industry, including with respect to data centers and public cloud;



•

Competition from our suppliers and other resellers for the products and services that we sell;



•

The volatility in our financial performance resulting from various factors, including the factors described above;



•

The limited trading volume of our common stock in the market;



•

The volatility in trading price of our common stock, which has at times been uncorrelated with our financial performance, and that only two recognized equity research analysts publish research reports regarding PCM;

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•

The challenges and risks that we have faced, and would likely continue to face, if we remained an independent company, including competition from much larger firms possessing greater financial resources and more comprehensive service offerings, including in some instances our suppliers, recruiting and retention of qualified personnel, changing client demands and pricing pressures, execution risks involved with the implementation of management's key objectives for PCM;



•

The additional costs and burdens involved with being a public company, and general market risks;



•

The risks and uncertainties inherent in our ability to execute on our strategic plan and achieve management's related financial projections, including the risks and uncertainties described under the heading "Risk Factors" in Item 1A, Part I of our Form 10-K for the period ended December 31, 2018, on file with the SEC, and in our other reports filed from time to time with the SEC; and



•

The view of the PCM board of directors that PCM has benefitted from the favorable domestic and international economic conditions that have prevailed in the years since the last major economic downturn, and if PCM were to remain an independent, publicly traded company, the value of its common shares would be susceptible to future changes and uncertainties in domestic and international economic conditions, including reduced demand for information technology products and services characteristic of prior economic downturns;



•

The results of the market check on Insight's $35.00 per share proposal performed by B. Riley between March 18, 2019 and May 17, 2019, consisting of inquiries to a group of 27 potential bidders, including nine financial sponsors and 18 strategic parties, eight of whom entered into confidentiality agreements with PCM and received information related to PCM, and the belief of the PCM board of directors that the merger consideration was the best price reasonably attainable for our stockholders;



•

The relationship of the merger consideration to the trading price of our common stock, including that the merger consideration constituted a premium of approximately 43.6% over the closing share price of $24.38 on June 21, 2019, the last trading day prior to the announcement of the execution of the merger agreement;



•

The valuation analyses regarding PCM and prepared by B. Riley and reviewed and discussed with the PCM board of directors, including the analyses summarized in the section entitled "—Opinion of Financial Advisor" beginning on page 36;



•

The oral opinion, subsequently confirmed in writing, provided to the PCM board of directors at its meeting on June 23, 2019 by representatives of B. Riley, as to the fairness, as of such date, from a financial point of view, to the holders of our outstanding common stock of the $35.00 per share in cash to be received by such holders in the merger pursuant to the merger agreement, based upon and subject to the qualifications, assumptions and other matters considered in connection with the preparation of such opinion, which opinion is more fully described below in the section entitled "—Opinion of Financial Advisor" (the full text of the written opinion of B. Riley is attached hereto as Annex C );



•

The certainty of value of the all-cash merger consideration, eliminating long-term business and execution risk;



•

The view of the PCM board of directors that the terms of the merger agreement would be unlikely to deter third parties willing to make an unsolicited acquisition proposal from doing so;

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•

The right of the PCM board of directors under the merger agreement to respond to a third party submitting an unsolicited acquisition proposal by providing non-public information subject to, among other conditions, an acceptable confidentiality agreement, and to engage in negotiations or substantive discussions with any such person, so long as the PCM board of directors first determines in good faith, after consultation with outside legal counsel, that (i) based on the information then available and after consultation with its outside financial advisors, such acquisition proposal either constitutes a superior proposal or would reasonably be expected to result in a superior proposal and (ii) the failure to take such action would be inconsistent with the directors' fiduciary duties under applicable law;



•

The right of the PCM board of directors, under certain circumstances, to withdraw, withhold, qualify or modify its recommendation that the PCM stockholders adopt the merger agreement; and



•

The right of the PCM board of directors to terminate the merger agreement in order to enter into an alternative acquisition agreement that the PCM board of directors determines in good faith, after consultation with its outside financial advisors and outside legal counsel to constitute a superior proposal, subject to certain conditions, provided that we concurrently pay a $16.6 million termination fee to Insight under circumstances as described in "The Merger Agreement—Termination Fee" beginning on page 85;



•

The other terms of the merger agreement, including:



•

the fact that the PCM board of directors believed that the termination fee of $16.6 million, or approximately 3.5% of the transaction value, is reasonable in light of, among other things, the benefits of the merger to our stockholders and the likelihood that a fee of such size would not be preclusive or unreasonably restrictive of other offers;



•

the conditions to the closing, including the belief of the PCM board of directors, with consultation with counsel, that, while the closing is subject to certain antitrust approvals, there were not likely to be significant antitrust or other regulatory impediments to the closing, as well as the obligations of Insight and Merger Sub to take actions to obtain such approvals;



•

the fact that the merger agreement is not conditioned on Insight obtaining any outside financing; and



•

the fact that the end date of November 20, 2019 under the merger agreement on which either party, subject to certain exceptions, can terminate the merger agreement, allows for sufficient time to consummate the merger;



•

The belief of the PCM board of directors, based on the arm's length negotiations described in "The Merger—Background of the Merger" beginning on page 24 of this proxy statement that led to the final merger agreement, that the price to be paid by Insight is the highest price per share that Insight was willing to pay and that the terms and conditions of the merger agreement were, in the view of the PCM board of directors, the most favorable to PCM and the PCM stockholders to which Insight was willing to agree;



•

The fact that Insight had obtained a debt financing commitment letter for the transaction;



•

The research analyst estimates, market multiples, precedent transactions, premium paid analysis and discounted cash flow analysis discussed beginning on page 36 under "—Opinion of Financial Advisor"; and



•

The availability of appraisal rights to our stockholders who comply with specified procedures under Section 262 of the DGCL.

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        In its deliberations concerning the merger and the other transactions contemplated by the merger agreement, the PCM board of directors also considered and balanced against the factors potentially weighing in favor of the merger a number of uncertainties, risks, restrictions and other factors potentially weighing against the merger, including the following (not necessarily in order of relative importance):

•

While Insight's obligations under the merger agreement would not be conditioned on Insight's ability to obtain financing for the transaction, Insight would require additional financing beyond its currently available capital resources in order to consummate the merger, and PCM would be obligated under the merger agreement to offer reasonable cooperation to Insight's financing efforts;



•

PCM's stockholders would forgo the opportunity to participate in future earnings or growth of PCM or the surviving corporation in the merger, or benefit from any future appreciation in the value of PCM's common stock, including as may result from PCM's execution of its current strategy as an independent public company;



•

Receipt of the all-cash merger consideration would be taxable to those of our stockholders that are treated as U.S. holders for U.S. federal income tax purposes;



•

Under specified circumstances, we may be required to pay fees and expenses in the event the merger agreement is terminated and the effect this could have on us, including:



•

the possibility that the $16.6 million termination fee payable by us to Insight upon the termination of the merger agreement under certain circumstances could discourage other potential acquirers from making a competing proposal, although the PCM board of directors believes that the termination fee was reasonable in amount and would not unduly deter any other party that might be interested in acquiring us; and



•

if the merger is not consummated, PCM will generally be required to pay its own expenses associated with the merger agreement and the transactions contemplated thereby;



•

The significant costs involved in connection with entering into and completing the merger and the substantial time and effort of management required to consummate the merger, which could disrupt our business operations;



•

The announcement and pendency of the merger, or the failure to complete the merger, may cause substantial harm to our relationships with its employees (including making it more difficult to attract and retain key personnel and the possible loss of key management and other personnel), vendors and customers;



•

The restrictions in the merger agreement on our ability to actively solicit competing bids to acquire PCM;



•

The effect that the right afforded to Insight under the merger agreement to match acquisition proposals from third parties may discourage other parties that might otherwise have an interest in acquiring PCM;



•

The restrictions on our conduct of business prior to completion of the merger, which could delay or prevent us from undertaking business opportunities that may arise or taking other actions with respect to our operations during the pendency of the merger, whether or not the merger is completed;



•

The risk that all conditions to the parties' obligations to consummate the merger may not be satisfied or that satisfaction of such conditions may be delayed;

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•

The market price of PCM's common stock could be affected by many factors, including: (i) if the merger agreement is terminated, the reason or reasons for such termination and whether such termination resulted from factors adversely affecting us; (ii) the possibility that, as a result of the termination of the merger agreement, possible acquirers may consider us to be an unattractive acquisition candidate; and (iii) the possible sale of our common stock by short-term investors following an announcement that the merger agreement has been terminated;



•

Certain of our directors and executive officers may have interests in the merger that may be deemed to be different from, or in addition to, those of our stockholders (the PCM board of directors was made aware of and considered these interests; for more information about such interests, see below under the heading "The Merger—Interests of PCM's Directors and Executive Officers in the Merger" beginning on page 47);



•

Litigation may occur in connection with the merger and such litigation may increase the costs associated with the merger and result in a diversion of management focus;



•

Completion of the merger would require antitrust clearance in the United States and Canada; and



•

The fact that within the past calendar year, PCM's stock had traded at prices above the merger consideration.

        The foregoing discussion of the information and factors considered by the PCM board of directors is not intended to be exhaustive, but includes material factors the PCM board of directors considered. In view of the variety of factors considered in connection with its evaluation of the merger and the complexity of these matters, the PCM board of directors did not find it useful and did not attempt to quantify or assign any relative or specific weights to the various factors considered in making its determination and recommendation. In addition, each of the members of the PCM board of directors may have given differing weights to different factors. Overall, the PCM board of directors believed that the positive factors supporting the merger outweighed the negative factors it considered.

        The explanation of the reasoning of the PCM board of directors and certain information presented in this section are forward-looking in nature and, therefore, the information should be read in light of the factors discussed in the sections titled "Cautionary Note Regarding Forward-Looking Statements" beginning on page 57.

Opinion of Financial Advisor

        PCM has retained B. Riley to act as PCM's financial advisor in connection with the transaction. B. Riley is an internationally recognized financial advisory firm that has substantial experience in the industry in which PCM operates.

        On June 23, 2019, at a meeting of the PCM board of directors held to evaluate the merger, B. Riley delivered to the PCM board of directors an oral opinion, which was confirmed by delivery of a written opinion dated June 23, 2019, to the effect that, as of the date of the opinion and based on and subject to various assumptions and limitations described in its opinion, the merger consideration in connection with the merger was fair to PCM's stockholders from a financial point of view.

         The full text of B. Riley's written opinion to the PCM board of directors, which describes, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken, is attached as Annex C to this proxy statement and is incorporated by reference herein in its entirety. The following summary of B. Riley's opinion is qualified in its entirety by reference to the full text of the opinion. B. Riley delivered its opinion to the PCM board of directors for the benefit and use of the PCM board of directors (in its capacity as such) in connection with and for purposes of its evaluation of the merger consideration from a financial point of view. B. Riley's

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opinion did not address any other aspect of the merger or the underlying business decision of PCM to effect the merger, and no opinion or view was expressed as to the relative merits of the merger in comparison to other strategies or transactions that might be available to PCM or in which PCM might engage. B. Riley's opinion does not constitute a recommendation to any stockholder as to how to vote or act in connection with the proposed merger or any related matter.

        In connection with rendering its opinion, B. Riley, among other things:

•

reviewed the financial terms of the final draft merger agreement;



•

reviewed certain information internal to PCM concerning its business, financial condition and operations, prepared and furnished to B. Riley by PCM's management;



•

reviewed the financial forecasts of PCM as furnished to B. Riley by PCM's management;



•

reviewed certain internal financial analyses, estimates and forecasts, prepared and furnished to B. Riley by PCM's management;



•

reviewed certain publicly available financial data, stock market performance data and trading multiples of PCM;



•

held discussion with members of senior management of PCM concerning their evaluations of the merger, the business, financial condition, and strategic objectives of PCM, as well as such other matters as B. Riley deemed necessary or appropriate for purposes of rendering its opinion;



•

reviewed certain publicly available financial data, stock market performance data and trading multiples of companies which B. Riley deemed to be generally comparable to PCM;



•

reviewed the publicly available financial terms of certain other business combinations that B. Riley deemed to be relevant in industries similar to those in which PCM participates and the consideration received for such companies that B. Riley believed to be generally relevant;



•

performed a discounted cash flow analysis of PCM utilizing financial information prepared by and furnished to B. Riley by PCM's management;



•

performed such other financial studies, analyses and investigations, and considered such other matters, as B. Riley deemed necessary or appropriate for purposes of rendering its opinion.

        For purposes of its analysis and opinion, B. Riley assumed and relied upon, without undertaking responsibility for independently verifying, and did not independently verify, the accuracy and completeness of the information reviewed by B. Riley, nor was B. Riley furnished with any such verification and B. Riley did not assume any responsibility or liability for the accuracy or completeness thereof. B. Riley did not make an independent evaluation or appraisal of the assets or the liabilities (contingent or otherwise) of PCM including those that may arise from the merger, nor has B. Riley evaluated the solvency of PCM under any state or federal laws. In addition, B. Riley did not undertake an independent analysis of any pending or threatened litigation, possible unasserted claims or other contingent liabilities to which PCM is a party or may be subject, and B. Riley's opinion does not make an assumption concerning, and therefore does not consider, the possible assertion of claims, outcomes or damages arising out of any such matters. B. Riley also relied, without assuming responsibility or liability for independent verification, upon the accuracy and completeness of all financial and other information available from public sources and all information provided to B. Riley or otherwise discussed with or reviewed by B. Riley.

        With respect to the financial and other projections prepared by PCM and the assumptions underlying those projections, including the amounts and the timing of all financial and other performance data, PCM management advised B. Riley, and B. Riley assumed, that such items were reasonably prepared by PCM in accordance with industry practice and reflected PCM management's

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best estimates and judgments as of their date of preparation. B. Riley expressed no view as to any such analyses or forecasts or the assumptions on which they were based. Further, B. Riley assumed that there had been no material change in the assets, financial condition, results of operations, business or prospects of PCM since the respective dates of the most recent financial statements made available to B. Riley, and B. Riley relied upon the assurances of PCM management that they were not aware of any facts that would make the information and projections provided by PCM management materially inaccurate, incomplete or misleading.

        For purposes of rendering its opinion, B. Riley assumed, with the consent of the PCM board of directors, that the executed forms of the merger agreement did not differ in any material respect from the last draft provided to B. Riley, and that the consummation of the merger will be effected in accordance with the terms and conditions of the merger agreement, without waiver, modification or amendment of any material term, condition or agreement, and that, in the course of obtaining the necessary regulatory or third party consents and approvals (contractual or otherwise) for the merger, no delay, limitation, restriction or condition will be imposed that would have an adverse effect on PCM or the contemplated benefits of the merger. In addition, events occurring after June 23, 2019 could materially affect the assumptions used in preparing B. Riley's opinion, but B. Riley has no obligation to reaffirm its opinion. B. Riley is not a legal, tax or regulatory advisor and relied upon, without independent verification, the assessment of PCM and PCM's legal, tax and regulatory advisors with respect to such matters.

        B. Riley's opinion did not address the underlying business decision of PCM to effect the merger and it is not a recommendation as to any action the PCM board of directors should take with respect to the merger or any aspect thereof. B. Riley's opinion is necessarily based on economic, market, monetary, regulatory and other conditions as they existed on and could be evaluated, and on the information made available to B. Riley, as of June 23, 2019. Subsequent developments may affect B. Riley's opinion, and B. Riley has no obligation to update or revise its opinion after June 23, 2019.

        B. Riley was not asked to opine upon, and expressed no opinion with respect to, any matter other than the fairness from a financial point of view, as of June 23, 2019, to the holders of PCM common stock of the merger consideration to be received by such holders of PCM common stock in the proposed merger. B. Riley did not express any view on, and its opinion does not address, any other aspect or implication of the merger agreement or merger or any aspect or implication of any other agreement or understanding entered into in connection with the merger or otherwise. B. Riley's opinion is limited to the fairness, from a financial point of view, to the PCM stockholders of the merger consideration in connection with the merger, and B. Riley expresses no opinion as to the fairness of (i) the merger to the holders of any other class of securities or options, creditors, or other constituencies of PCM nor (ii) the amount or nature of the compensation to any of the officers, directors or employees of PCM, or other class of such persons, relative to the merger consideration. B. Riley's opinion does not address the prices or trading ranges at which the PCM common stock will trade at any time prior to the consummation of the merger or the impact of the merger on the solvency or viability of PCM or the ability of PCM to pay its obligations when they become due before consummation of the merger.

        The following is a summary of the material financial analyses presented by B. Riley to the PCM board of directors in connection with rendering its opinion. The following summary, however, does not purport to be a complete description of the financial analyses performed by B. Riley. The order of the analyses described and the results of these analyses do not represent relative importance or weight given to these analyses by B. Riley. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before June 23, 2019, and is not necessarily indicative of current market conditions.

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        The following summary of financial analyses includes information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of B. Riley's financial analyses.

Selected Precedent Transactions Analysis

        B. Riley reviewed publicly available information relating to the following selected transactions within the technology industry announced since March 2010 and involving transactions with implied enterprise values, which we refer to as EV, in excess of $13 million. For each target company, B. Riley calculated the implied EV as a multiple of Adjusted EBITDA for the trailing twelve-month, which we refer to as LTM, period prior to the close of the respective transaction, which we refer to below as EV/LTM Adj. EBITDA, and then calculated the mean and median for the transactions.

        B. Riley chose the selected transactions for purposes of this analysis based on its professional judgment and experience, taking into account comparability to PCM with respect to the industry of operation, business model, and geographic footprint. No transaction reviewed was directly comparable to the proposed merger. Accordingly, this analysis involved complex considerations and judgments concerning differences in financial and operating characteristics of PCM relative to the targets in the selected transactions and other factors that would affect the acquisition values in the selected precedent transactions. B. Riley excluded certain comparable transactions due to lack of transparency in transaction details (such as price, corresponding multiples paid and financial characteristics of the target company). With respect to the Adjusted EBITDA numbers for target companies used in calculating the EV/LTM Adj. EBITDA multiples, B. Riley used either the Adjusted EBITDA as disclosed by such target company or adjusted the EBITDA for such company based on publicly available information.

        Based on B. Riley's professional judgment taking into account the mean and median EV/LTM Adj. EBITDA multiples referenced above, B. Riley noted that, per the selected precedent transaction analysis, the merger consideration exceeded the implied equity value per share calculated by applying the mean and median valuation multiples to PCM's Adjusted EBITDA for the LTM period ended March 31, 2019. From this analysis, and using an Adjusted EBITDA multiple range of 7x to 8x and net

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debt of $106.4 million, B. Riley derived a range of implied equity value per share of PCM common stock of $25.00 to $29.51.

        For a discussion of Adjusted EBITDA, see "Certain Unaudited Prospective Financial Information of PCM" below on page 44.

Selected Public Company Trading Comparables Analysis

        B. Riley reviewed and compared certain financial information for PCM to corresponding financial information for the following publicly traded companies, which, in the exercise of its professional judgment, B. Riley determined to be relevant to its analysis. In selecting comparable public companies, B. Riley focused on businesses with a similar business model, end-markets and company size. The selected companies were as follows:

•

CDW Corporation (CDW)



•

Insight Enterprises, Inc. (NSIT)



•

ePlus inc. (PLUS)



•

PC Connection, Inc. (CNXN)

        B. Riley obtained financial metrics and projections for the selected companies from documents filed by such companies with the SEC and S&P Capital IQ. In its public company trading comparables analysis, B. Riley conducted an EV analysis and derived and compared multiples for PCM and the selected companies, calculated as follows:

•

the EV as a multiple of Adjusted EBITDA for the LTM period ended March 31, 2019, which is referred to below as "EV/LTM 3/31/19 Adj. EBITDA"; and



•

the EV as a multiple of estimated Adjusted EBITDA for 2019, which is referred to below as "EV/CY2019E Adj. EBITDA".

        B. Riley then compared PCM's EV as a multiple of Adjusted EBITDA for the LTM period ended March 31, 2019, and as a multiple of estimated Adjusted EBITDA for 2019. A summary of this comparison is shown in the table below.

        This EV analysis yielded the following:

        No selected company is identical to PCM. Accordingly, B. Riley's comparison of selected companies to PCM and analysis of the results of such comparisons were not purely quantitative, but instead necessarily involved qualitative considerations and professional judgments concerning differences in financial and operating characteristics and other factors that could affect the relative

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value of PCM. From this analysis and using a range of multiples from 7x to 8x on PCM's estimated Adjusted EBITDA for 2019, B. Riley derived a range of implied equity value per share of PCM common stock of $28.35 to $33.33.

Discounted Cash Flow Analysis

        B. Riley conducted an illustrative discounted cash flow analysis for PCM on a stand-alone basis. B. Riley calculated a range of implied values of PCM based on (i) forecasts for calendar years 2019 through 2021 provided by PCM management and (ii) B. Riley estimates for calendar years 2022 and 2023. B. Riley first calculated unlevered free cash flows (calculated as net profit after taxes, plus depreciation and amortization, less the amount of any increase or plus the amount of any decrease in net working capital and less capital expenditures) of PCM for calendar years 2019 through 2023. Net profit after taxes was calculated as Adjusted EBITDA less depreciation and amortization, stock-based compensation and taxes. B. Riley also calculated terminal values for PCM by applying exit multiples ranging from 6.5x-7.5x (which were selected based on B. Riley's professional judgment, taking into account acquisition multiples paid in various comparable transactions in differing phases of the macroeconomic cycle) to PCM's estimated 2023 calendar year Adjusted EBITDA. The unlevered free cash flows and terminal values were then discounted to present values using a weighted average cost of capital range of 13.0% to 14.0% (which range was selected based on B. Riley's professional judgment and derived from an analysis of the estimated weighted average cost of capital using PCM data, based on a capital asset pricing model, taking into account PCM's size, PCM's exposure to market risk and overall historical equity market returns) to calculate a range of implied values for PCM. From this analysis, B. Riley derived a range of implied equity value per share of PCM common stock of $33.45 to $39.81.

Premiums Paid Analysis

        B. Riley also reviewed and analyzed the premiums paid in recent acquisitions of a group of publicly held companies, with data sourced from Capital IQ and B. Riley investment banking analyses. The analysis examined the ratio between the acquisition price and the target company's price per share one day, one week and one month prior to the announcement of the transaction. In selecting comparable transactions for the premiums paid analysis, B. Riley only included change-in-control transactions involving U.S. public company targets for the five-year period ending June 21, 2019. A total of 1,522 transactions were analyzed, 723 of which involved small-cap transactions (defined as transactions with a deal value of less than $500 million). The total transactions had a mean and median transaction size of $3,886.9 million and $442.4 million, respectively. The small-cap transactions had a mean and median transaction size of $119.4 million and $61.4 million, respectively. For these transactions, the median transaction premium paid: (i) based on the target company's price per share one day prior to the announcement, ranged from 25.9% to 33.3%; (ii) based on the target company's price per share one week prior to the announcement, ranged from 27.4% to 33.8%; and (iii) based on the target company's price per share one month prior to the announcement, ranged from 30.9% to $33.5% (in each case where the low end of the range represented all transactions in aggregate and the high end of the range represented small-cap transactions). B. Riley noted that applying these metrics implied per share price ranges for PCM common stock of $30.69 to $32.49 (for one day prior comparison), $32.77 to $34.41 (for one week prior comparison) and $37.45 to $38.21 (for one month prior comparison). B. Riley further noted that the $35.00 per share cash consideration to be received by PCM stockholders represented a 43.6% premium to the PCM closing stock price of $24.38 on June 21, 2019.

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Equity Research Analyst Price Targets

        For reference only and not as a basis for the rendering of its opinion, B. Riley reviewed the two publicly available equity research analyst price targets for PCM's common stock available as of June 21, 2019—prepared by each of B. Riley and Roth Capital Partners, LLC on April 26, 2019. B. Riley noted that the B. Riley price target was $34.50 per share and the Roth Capital Partners, LLC price target was $36.00 per share, and compared that range to the closing price per share of PCM common stock of $24.38 as of June 21, 2019, and the $35.00 per share cash consideration to be received by PCM stockholders. The closing price per share of PCM's common stock on April 26, 2019, the date of the equity research analyst price targets reviewed, was $27.43.

Certain Supplemental Information Provided to Board

        B. Riley presented historical trading prices of PCM common stock over the 52-week period ending June 21, 2019, calculated the volume-weighted average daily closing prices for PCM common stock over various time periods and noted the closing stock price on selected dates prior to and including June 21, 2019, including the 52-week high and low closing stock prices. PCM's common stock price per share ranged from $14.16 to $39.69 over the 52-week period ended on June 21, 2019. This analysis indicated that the $35.00 per share cash consideration to be received by PCM stockholders represented a premium of:

•

43.6% based on the closing price per share of $24.38 on June 21, 2019, the last full trading day before B. Riley delivered the fairness opinion to the board;



•

37.0% based on the volume-weighted average closing price per share of $25.55 over the 30-day period ending June 21, 2019;



•

27.8% based on the volume-weighted average closing price per share of $27.39 over the 60-day period ending June 21, 2019;



•

12.7% based on the volume-weighted average closing price per share of $31.05 over the 90-day period ending June 21, 2019;



•

(11.8)% based on the 52-week high closing price per share of $39.69; and



•

147.3% based on the 52-week low closing price per share of $14.16.

General

        The preparation of a fairness opinion involves various determinations as to the most appropriate and relevant methods of financial analysis and the application of such methods to the particular circumstances and, therefore, a fairness opinion is not readily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying B. Riley's opinion. In arriving at its fairness opinion, B. Riley considered the results of all of its analyses and, except as expressly stated above, did not attribute any particular weight to any factor or analysis considered by it. Rather, B. Riley made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to PCM or the merger. B. Riley prepared these analyses for purposes of providing its opinion to the board as to the fairness from a financial point of view, to the holders of shares of PCM common stock of the merger consideration to be received by such holders in the merger. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to

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uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of PCM, Insight, Merger Sub, B. Riley or any other person assumes responsibility if future results are materially different from those forecast.

        The merger consideration was determined through arm's-length negotiations between PCM and Insight and was approved by the PCM board of directors by unanimous vote following a presentation to the PCM board of directors. B. Riley, however, did not recommend any specific amount of consideration to the board or that any specific amount of consideration constituted the only appropriate consideration for the merger. As described above, B. Riley's opinion to the PCM board of directors was one of many factors taken into consideration by the PCM board of directors in making its determination to approve the merger. The foregoing summary does not purport to be a complete description of the analyses performed by B. Riley in connection with the fairness opinion and is qualified in its entirety by reference to the written opinion of B. Riley, which is included as Annex C to this proxy statement and is incorporated herein by reference.

        B. Riley's opinion was approved by a fairness opinion committee of B. Riley professionals in accordance with established procedures.

        During the past two years, B. Riley has received commissions from PCM in the amount of $21,138 in connection with PCM's discretionary stock repurchase program. Other than that, during the past two years, PCM has not engaged B. Riley to provide, and B. Riley has not provided, investment banking, financial advisory or other financial services to PCM unrelated to the merger for which PCM has paid or expects to pay fees to B. Riley. During the past two years, Insight has not engaged B. Riley to provide, and B. Riley has not provided, investment banking, financial advisory or other financial services to Insight for which Insight has paid or expects to pay fees to B. Riley.

        B. Riley and its affiliates are engaged in a broad range of securities activities and financial advisory services. B. Riley and its affiliates carry on a range of businesses for their own account and for their customers, including providing stock brokerage, investment advisory, investment management, proprietary financings and custodial services. In the ordinary course of business, B. Riley or its affiliates may actively trade or hold (for their own accounts or for the accounts of their customers) equity or debt securities, bank debt and/or other financial instruments, of (i) PCM and affiliates of PCM, (ii) Insight and affiliates of Insight, and (iii) any other company that may be involved in the merger as well as derivatives thereof, and, accordingly, may at any time hold long or short positions in such securities, bank debt, financial instruments and derivatives.

        B. Riley has acted as exclusive financial advisor to the PCM for purposes of issuing an opinion as to the fairness, from a financial point of view, of the merger consideration, to the board and, further, for purposes of providing advisory services in connection with a possible sale, transfer or other disposition, directly or indirectly, of all or a material portion of the equity securities, assets or business of PCM or its subsidiaries, including assisting in the evaluation of PCM's strategic alternatives. The PCM board of directors selected B. Riley as its exclusive financial advisor because it is an internationally recognized financial advisory firm that has substantial experience in the industries in which PCM operates.

        B. Riley received a fee of $500,000 as a result of the delivery of its fairness opinion. No portion of the fairness opinion fee was contingent upon the conclusions reached in the opinion or the closing of the merger. Additionally, if a sale transaction, including the merger, is consummated during the term of B. Riley's engagement or within six months following the termination thereof, or if PCM receives a proposal or enters into an agreement with respect to a potential sale transaction within six months after the termination of B. Riley's engagement and such sale transaction is subsequently consummated at the same $35.00 per share acquisition price, then B. Riley will receive an advisory fee of $3,321,000, which fee will be reduced by the $500,000 already paid to B. Riley for delivery of its fairness opinion. PCM has also agreed to reimburse B. Riley for certain expenses, not to exceed $100,000, and to indemnify

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B. Riley, its controlling persons, representatives and agents against certain liabilities associated with the issuance of its opinion.

Certain Unaudited Prospective Financial Information of PCM

        PCM does not, as a matter of general practice, publicly disclose financial forecasts or internal projections as to future performance, earnings or other results due to, among other reasons, the inherent difficulty of accurately predicting financial performance for future periods and the uncertainty of underlying assumptions and estimates. However, in connection with the merger, PCM management prepared selected, non-public financial projections, which we refer to as the management projections, for calendar years 2019, 2020 and 2021 and provided such projections to the PCM board of directors, in connection with the consideration by the PCM board of directors of the merger, and to its financial advisor, B. Riley, in connection with its financial analyses described above under "—Opinion of Financial Advisor." The management projections were also provided to Insight in connection with its due diligence review of a possible transaction.

        With the approval of PCM management, B. Riley calculated PCM's Adjusted EBIT, increase (decrease) in net working capital, and unlevered free cash flows for the calendar years 2019, 2020 and 2021, in each case, from line items in the income statement and balance sheet projections for such years provided by PCM management. With the approval of PCM management, B. Riley delivered these calculations to the PCM board of directors in connection with the consideration by the PCM board of directors of the merger and used such calculations in connection with its financial analysis described above under "—Opinion of Financial Advisor."

        Additionally, with the approval of PCM management, and based upon assumptions approved by PCM management, B. Riley prepared selected, non-public financial projections for calendar years 2022 and 2023, delivered these projections to the PCM board of directors in connection with the consideration by the PCM board of directors of the merger and used such projections in connection with its financial analysis described above under "—Opinion of Financial Advisor."

        We have included a summary of (i) the management projections, (ii) PCM's projected Adjusted EBIT, increase (decrease) in net working capital and unlevered free cash flow, as calculated by B. Riley based on the management projections, and (iii) the projections prepared by B. Riley based upon assumptions approved by PCM management, which we refer to herein collectively as the projections, below, only because this information was used by PCM's board of directors and B. Riley in connection with the process resulting in the merger agreement. The projections were not prepared with a view towards public disclosure and the inclusion of these projections in this proxy statement does not constitute an admission or representation by PCM that the projections are material. The projections constitute forward-looking statements. See "Cautionary Note Regarding Forward-Looking Statements."

        PCM advised the recipients of the projections that such projections are inherently subjective in many respects. The projections are based on a variety of estimates and assumptions made by our senior management regarding PCM's business, industry performance, general business, economic, market and financial conditions and other matters, many of which are difficult to predict and are beyond PCM's control.

        The projections were prepared in good faith and on a reasonable basis based on the best information available to the preparers at the time of their preparation. The projections, however, are not actual results and should not be relied upon as being necessarily indicative of actual future results, and readers of this proxy statement are cautioned not to place undue reliance on this information. Except as required by law, PCM does not intend to update these projections or to make other projections public in the future.

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        In preparing the projections for calendar years 2022 and 2023, B. Riley assumed a sales growth rate of 5.0% per year in 2022 and 2023, based on its professional judgment and in light of annual growth rates in the industry and PCM management's sales forecasts for 2019 to 2021. B. Riley then applied the estimated 2021 Adjusted EBITDA as a percentage of sales of 4.5% to the 2022 and 2023 sales projections to arrive at 2022 and 2023 Adjusted EBITDA projections. Utilizing the same methodology, B. Riley arrived at the depreciation and amortization and capital expenditures projections for 2022 and 2023. For increase (decrease) in net working capital, B. Riley projected the 2022 and 2023 balance sheet accounts by applying the projected 2021 balance sheet account ratios prepared by PCM management to the 2022 and 2023 income statement projections and then calculating the year-over-year changes.

        Neither PCM's independent auditors, nor any other independent accountants, have compiled, examined or performed any procedures with respect to the projections, nor have they expressed any opinion or any other form of assurance with respect thereto. The projections were not prepared with a view toward public disclosure or compliance with generally accepted accounting principles in the United States ("GAAP"), the published guidelines of the SEC regarding projections or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information.

        In addition, because the projections cover multiple years, such information by its nature becomes less predictive with each successive year and becomes subject to increasing uncertainty in the years beyond 2019. While presented with numeric specificity, the assumptions upon which the projections were based necessarily involve judgments with respect to, among other things, future economic and competitive conditions, many of which are difficult to predict accurately. See the risk factors included in our most recent filings on Form 10-Q and Form 10-K. Also, the economic and business environments can and do change quickly, which adds a significant level of unpredictability and execution risk. It is expected that differences between actual and projected results will occur, and actual results may be materially greater or less than those contained in the projections. There can be no assurance that the projections, or the assumptions underlying the projections, will be realized. Accordingly, readers of this proxy statement are cautioned not to place undue reliance on the projections included in this proxy statement.

        In addition, the projections do not take into account the possible financial and other effects on PCM of the merger and do not attempt to predict or suggest future results of the surviving corporation in the merger. The projections do not give effect to any of the merger, the impact of negotiating or executing the merger agreement, the expenses that may be incurred in connection with consummating the merger, any synergies that may be achieved following the merger, the effect on PCM of any business or strategic decision or action that has been or will be taken as a result of the merger agreement having been executed, or the effect of any business or strategic decisions or actions that may have been taken if the merger agreement had not been executed. Further, the projections do not take into account the effect of any possible failure of the merger to occur.

        The following is a summary of the (unaudited) management projections (in millions):

        The following is a summary of the (unaudited) calculations of Adjusted EBIT, increase (decrease) in net working capital and unlevered free cash flow for 2019, 2020 and 2021 performed by B. Riley

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based upon line items in the income statement and balance sheet projections for such years prepared by PCM management (in millions):

        The following is a summary of the (unaudited) projections for 2022 and 2023 prepared by B. Riley with the approval of PCM management, based on assumptions approved by PCM management (in millions):

        Adjusted EBITDA, Adjusted EBIT and unlevered free cash flows are financial measures that are not determined in accordance with accounting principles generally accepted in the United States of America, or GAAP, and therefore should not be considered as a substitute for, financial information presented in compliance with GAAP. The non-GAAP measures were included because they were used by B. Riley and the PCM board of directors in connection with the process that resulted in the merger agreement.

        EBIT refers to earnings before interest and taxes, and EBITDA refers to earnings before interest, taxes, depreciation and amortization. Adjusted EBITDA and Adjusted EBIT remove the effect of severance and restructuring related expenses related to PCM's cost reduction initiatives and stock-based compensation, as well as uncommon, non-recurring or special items.

        Unlevered free cash flow refers to Adjusted EBITDA (i) less stock-based compensation, (ii) less taxes (applying a 28.0% cash tax rate as provided by PCM), (iii) less capital expenditures and (iv) less the cash impact of net working capital based on information provided by PCM.

        Other companies in our industry may calculate Adjusted EBIT, Adjusted EBITDA and unlevered free cash flow differently than we do, which may limit their usefulness as comparative measures.

         You should not regard the inclusion of these projections in this proxy statement as an indication that PCM or any of its affiliates, advisors or other representatives considered or consider the projections to be necessarily predictive of actual future events. None of PCM or any of its affiliates, advisors or other representatives has made or makes any representations regarding the ultimate performance of PCM compared to the information contained in the projections. PCM has not made and makes no representation to Insight or any stockholder in the merger agreement or otherwise concerning the projections or regarding PCM's ultimate performance compared to the information contained in these projections or that the projected results will be achieved. PCM encourages all stockholders to review PCM's most recent SEC filings for a description of PCM's reported financial results.

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Financing Related to the Merger

        The merger agreement is not conditioned upon receipt of financing by Insight. Insight has obtained a financing commitment for the purpose of financing the transactions contemplated by the merger agreement, including payment of the merger consideration, payment of certain outstanding indebtedness of PCM and its subsidiaries, and payment of related fees and expenses, which we refer to as the financing. JPMorgan Chase Bank, N.A., which we refer to as the lender, has agreed to provide Insight with debt financing in an aggregate principal amount of up to $1,500 million on the terms set forth in a debt commitment letter provided to Insight. The obligations of the lender to provide debt financing under the debt commitment letter are subject to customary terms and conditions. The merger agreement provides that Insight will use commercially reasonable efforts to do all things necessary, proper or advisable to arrange and consummate the financing on or prior to the effective time.

Interests of PCM's Directors and Executive Officers in the Merger

        As reflected in the table set forth in the section entitled "Certain Beneficial Owners of PCM Common Stock" beginning on page 96 of this proxy statement, our officers and directors and certain affiliated trusts own shares representing an aggregate 26.3% interest in PCM. If the merger is consummated, these persons holding our shares will receive the per share merger consideration for each share of PCM common stock owned immediately prior to the effective time.

        In considering the recommendations of the PCM board with respect to the merger agreement, you should be aware that, aside from their interests as stockholders of PCM, PCM's directors and executive officers have interests in the merger that may be different from, or in addition to, those of other stockholders of PCM generally. The members of the PCM board of directors were aware of and considered these interests, among other matters, in evaluating and negotiating the merger agreement and the merger, and when making its recommendation to the PCM stockholders that the merger agreement be adopted. See the sections entitled "The Merger—Background of the Merger" beginning on page 24 of this proxy statement and "The Merger—Recommendation of the PCM Board of Directors; Reasons for the Merger" beginning on page 32 of this proxy statement.

        PCM stockholders should take these interests into account in deciding whether to vote " FOR " the adoption of the merger agreement. These interests are described in more detail below.

Indemnification and Insurance

        PCM's certificate of incorporation provides for the potential indemnification of directors and executive officers against certain liabilities that may arise by reason of their status or service as directors or executive officers. We have entered into indemnification agreements with each of our current directors and executive officers that provide the maximum indemnity available to directors and officers under Section 145 of the DGCL and our certificate of incorporation, as well as certain procedural protections. In addition, pursuant to the merger agreement, PCM's directors and executive officers will be entitled to certain ongoing indemnification from Insight and the surviving corporation and coverage under directors' and officers' liability insurance policies. The indemnification and insurance provisions in the merger agreement are further described in the section entitled "The Merger Agreement—Indemnification and Insurance" beginning on page 80 of this proxy statement.

Voting by PCM's Directors and Executive Officers

        At the close of business on the record date for the special meeting, PCM's directors and executive officers beneficially owned and had the right to vote 2,836,535 shares of our common stock, which represents approximately 23% of the shares of our common stock entitled to vote at the special meeting.

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        Concurrently with the execution of the merger agreement, certain stockholders of PCM identified therein, including each of PCM's directors and executive officers and certain affiliated trusts, entered into a voting agreement with Insight, Merger Sub and PCM, pursuant to which, among other matters and upon the terms and subject to the conditions set forth in the voting agreement, each such stockholder agreed, and upon the execution of the voting agreement is contractually obligated, to vote in favor of the adoption of the merger agreement and approval of the transactions contemplated thereby, including the merger, and against any proposal that would reasonably be expected to result in an alternative transaction and any action that is intended or would reasonably be expected to prevent or materially delay the consummation of the merger and the other transactions contemplated by the merger agreement. The voting agreement is attached to this proxy statement as Annex B . For a further discussion of the voting agreement, see "Information about the Special Meeting—Voting Agreement" beginning on page 60 of this proxy statement.

        PCM's directors and executive officers have informed PCM that they currently intend to vote all such shares of our common stock:

•

" FOR" the proposal to adopt the merger agreement; and



•

" FOR " the adjournment proposal.

Change of Control Severance Benefits Agreements with Named Executive Officers

        We have previously entered into employment and/or severance agreements with our Chief Executive Officer, Chief Financial Officer and our three other most highly compensated executive officers for fiscal year 2018, or, collectively, the Named Executive Officers. These agreements require us, among other things, to make payments upon a termination or constructive termination of employment and/or upon a change of control of PCM. A brief description of the potential severance and/or change of control related benefits that could be provided to each Named Executive Officer is provided below.

Frank F. Khulusi

        In January 1995, prior to our initial public offering, we entered into an employment agreement with Frank F. Khulusi, our Chairman and Chief Executive Officer, which we refer to as the Khulusi agreement, which was amended in December 2005 and in December 2008. The Khulusi agreement provides that Mr. Khulusi is entitled to certain severance benefits in the event of a change of control or if his employment is terminated by us without cause or by Mr. Khulusi for good reason.

        Upon consummation of a change of control of PCM, the Khulusi agreement (and Mr. Khulusi's employment with PCM) will automatically terminate and Mr. Khulusi will receive from PCM a lump sum payment equal to two times the sum of the total salary and short-term cash incentive compensation paid to him for the twelve months immediately preceding the change of control.

        Under the Khulusi agreement, a "change of control" of PCM will be deemed to have occurred if:

•

there is consummated (i) any consolidation or merger of PCM in which PCM is not the continuing or surviving corporation or pursuant to which shares of PCM's common stock would be converted into cash, securities or other property, other than a merger of PCM in which the holders of PCM's common stock immediately prior to the merger have the same proportionate ownership of common stock of the surviving corporation immediately after the merger, (ii) any reverse merger in which PCM is the continuing or surviving corporation but in which securities possessing more than 50% of the total combined voting power of PCM's outstanding securities are transferred to a person or persons different from those who hold such securities immediately prior to the merger, or (iii) any sale, lease, exchange or other transfer (in one or more related transactions) of all, or substantially all, of the assets of PCM;

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•

our stockholders approve a plan or proposal for the liquidation or dissolution of PCM;



•

any person other than Mr. Khulusi or certain of his relatives or affiliates becomes the direct or indirect beneficial owner of 20% or more of our common stock (other than as a result of purchases by such person directly from us); or



•

during any 12-month period, individuals who at the beginning of the period constitute our entire board of directors cease for any reason to constitute a majority thereof unless the election, or the nomination for election by our stockholders, of each new director was approved by a vote of at least a majority of the directors then still in office who were directors at the beginning of the period.

Brandon LaVerne

        In January 2006, we entered into a severance agreement, as amended on June 23, 2019, with Brandon LaVerne, our Chief Financial Officer, which we refer to as the LaVerne agreement. The LaVerne agreement provides that Mr. LaVerne is entitled to certain severance benefits in the event his employment is terminated by us without "cause" (as defined in the LaVerne agreement and described further below) or by Mr. LaVerne for "good reason" (as defined in the LaVerne agreement and described further below). These severance benefits are six months of his annual base salary plus twelve months of continued PCM-paid COBRA medical benefits. The severance benefits are contingent upon Mr. LaVerne's execution of a severance and release agreement and the cash severance would be paid by PCM in installments over the six months following termination of employment.

Robert Jay Miley

        In October 2014, we entered into an employment agreement, as amended on June 23, 2019, with Robert Jay Miley, our President, which we refer to as the Miley agreement. The Miley agreement provides that Mr. Miley is entitled to certain severance benefits in the event his employment is terminated by us without "cause" (as defined in the Miley agreement and described further below). These severance benefits are twelve months of his annual base salary and are conditioned upon Mr. Miley's (i) execution of a severance and release agreement and (ii) continuing compliance with the obligations set forth in his non-competition, non-disclosure and non-solicitation agreement with PCM, including noncompete obligations that will extend for 18 months after termination and non-solicitation obligations that will extend for 24 months after termination. The severance payment would be paid by PCM in one lump sum after the release agreement is effective.

Robert Newton

        In June 2004, we entered into an employment agreement, as amended in March 2005 and on June 23, 2019, with Robert Newton, our Executive Vice President, Chief Legal Officer and Secretary, which we refer to as the Newton agreement. The Newton agreement provides that Mr. Newton is entitled to certain severance benefits in the event his employment is terminated by us without "cause" (as defined in the Newton agreement and described further below) or by Mr. Newton for "good reason" (as defined in the Newton agreement and described further below). These severance benefits are six months of his annual base salary plus twelve months of continued PCM-paid COBRA medical benefits. The severance benefits are conditioned upon Mr. Newton's (i) execution of a severance and release agreement and (ii) continuing compliance with his nonsolicitation of PCM employees obligation that will extend for two years after termination and his nonsolicitation of PCM business obligation that will extend for one year after termination of employment. The cash severance would be paid by PCM in installments over the six months following termination of employment.

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Simon Abuyounes

        In June 2005, we entered into a severance agreement, as amended on June 23, 2019, with Simon Abuyounes, our Executive Vice President—IT and Operations, which we refer to as the Abuyounes agreement. The Abuyounes agreement provides that Mr. Abuyounes is entitled to certain severance benefits in the event his employment is terminated by us without "cause" (as defined in the Abuyounes agreement and described further below) or by Mr. Abuyounes for "good reason" (as defined in the Abuyounes agreement and described further below). These severance benefits are six months of his annual base salary plus twelve months of continued PCM-paid COBRA medical benefits. The severance benefits are contingent upon Mr. Abuyounes' execution of a severance and release agreement and the cash severance would be paid by PCM in installments over the six months following termination of employment.

Cause and Good Reason Definitions

        Under the above agreements for Messrs. LaVerne, Miley, Newton and Abuyounes, as amended June 23, 2019, "cause" generally means: (i) a material breach by the executive of any term set forth in the applicable employment or severance agreement; (ii) failure to follow the reasonable instructions of PCM; (iii) misconduct on the executive's part that is materially injurious to PCM, monetarily or otherwise, including misappropriation of trade secrets, fraud, or embezzlement; (iv) the executive's conviction for fraud or any other felony; or (v) if the executive exhibits in regard to his employment unavailability for service, misconduct, dishonesty or habitual neglect.

        Under the above agreements for Messrs. LaVerne, Newton and Abuyounes, as amended June 23, 2019, "good reason" generally means the occurrence of any one or more of the following without the executive's written consent: (i) a material reduction of the material duties and responsibilities assigned to the executive, (ii) a material reduction (of at least ten percent in the aggregate) in the executive's base salary; (iii) a material reduction (of at least ten percent in the aggregate) in the executive's annual bonus opportunity; (iv) a relocation of the executive's principal place of employment to a new location that is more than fifty (50) miles away; or (v) PCM's material breach of the applicable employment or severance agreement. The executive must generally provide PCM with written notice that he believes an event of good reason has occurred and afford us the opportunity to cure such event before the executive can resign for good reason.

        The employment and severance agreements and the benefits provided to our Named Executive Officers under these agreements were approved by the compensation committee of the PCM board of directors, which we refer to as the Compensation Committee, or the full PCM board of directors and were determined to be reasonable and necessary in order to hire and retain these individuals.

Transaction Bonuses

        On June 23, 2019, in recognition of their efforts in connection with the merger, each of the Compensation Committee and the full PCM board of directors approved the following special transaction bonuses, which we refer to as the transaction bonuses, to be paid in cash to the following Named Executive Officers of PCM in connection with the consummation of the merger. These bonuses will be paid pursuant to the Transaction Bonus Plan, which was approved and adopted by each of the Compensation Committee and the full PCM board of directors on June 23, 2019, which we refer to as the Transaction Bonus Plan.

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        See also the section entitled "The Merger—Interests of PCM's Directors and Executive Officers in the Merger—Golden Parachute Compensation Arrangements" beginning on page 51 of this proxy statement.

Golden Parachute Compensation Arrangements

Background

        This section sets forth the information required by Item 402(t) of Regulation S-K regarding the compensation for each of PCM'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 executive compensation disclosure rules, and in this section such term is used to describe the merger-related "golden parachute" compensation that is potentially payable to PCM's Named Executive Officers.

        As described in the section entitled "The Merger—Change of Control Severance Benefits Agreements with Named Executive Officers" beginning on page 48 of this proxy statement, PCM has entered into employment agreements and/or severance agreements with its Named Executive Officers that specify certain payments and benefits to be provided by PCM upon various circumstances, including, among other things, a qualifying termination of employment and/or the occurrence of a change of control of PCM.

        As described in the section entitled "The Merger—Transaction Bonuses" beginning on page 50 of this proxy statement, three of the Named Executive Officers will be eligible to receive merger-related transaction bonuses with a potential aggregate maximum payout to all participants of $600,000. Upon the closing of the merger, PCM will pay a $200,000 transaction bonus to each of Messrs. LaVerne, Newton and Abuyounes pursuant to the Transaction Bonus Plan, provided that each recipient has remained in service with PCM through the effective time of the merger.

        In accordance with the SEC's compliance rules regarding "golden parachute" compensation, the Golden Parachute Compensation table below sets forth the estimated amounts of certain compensation that each Named Executive Officer could receive in connection with the proposed merger. The estimates below are based in part on the following assumptions:

•

The merger, which will constitute a change of control of PCM, hypothetically closed on July 15, 2019, the latest practicable date prior to the filing of this proxy statement;



•

The per share merger consideration to be paid to stockholders for each share of PCM common stock upon closing pursuant to the merger agreement will be $35.00, without interest and less any applicable withholding taxes;



•

Each Named Executive Officer will remain in service with PCM until the closing and will then hypothetically experience a qualifying involuntary termination of employment pursuant to the employment agreement or severance agreement between such Named Executive Officer and PCM, as applicable, as of the end of the day on the closing (with the exception of Mr. Khulusi, this termination is purely hypothetical and is solely for purposes of showing estimated severance compensation); and



•

All then-outstanding unvested equity compensation awards held by each Named Executive Officer will remain outstanding, as is, until the closing whereupon they will become fully vested in accordance with the merger agreement and paid out in cash.

        The actual amount of any payments (if any) will likely differ from the below estimated amounts. No Named Executive Officer is entitled to any tax reimbursement payments from PCM.

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