tm2210566-1_prem14a - none

[PRELIMINARY PROXY STATEMENT — SUBJECT TO COMPLETION]

Mandiant, Inc.
11951 Freedom Drive, 6th Floor
Reston, VA 20190

To the Stockholders of Mandiant, Inc.:

You are cordially invited to attend a special meeting of stockholders (which we refer to as the “special meeting”) of Mandiant, Inc. (which we refer to as “Mandiant”). The special meeting will be held on [•], 2022, at [•] [a.m./p.m.], Pacific time. You may attend the special meeting via a live interactive webcast on the internet at [•]. You will be able to listen to the special meeting live and vote online. We elected to use a virtual meeting given the current public health implications of COVID-19 and our desire to promote the health and welfare of our stockholders, as well as our positive experiences with virtual meetings.

At the special meeting, you will be asked to consider and vote on a proposal to adopt the Agreement and Plan of Merger (as it may be amended from time to time), dated March 7, 2022 (which we refer to as the “merger agreement”), between Google LLC (which we refer to as “Parent”), Dupin Inc., a wholly owned subsidiary of Parent (which we refer to as “Merger Sub”) and Mandiant. We refer to the merger of Merger Sub with and into Mandiant as the “merger.” At the special meeting, you will also be asked to consider and vote on (1) a proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger; and (2) a proposal for the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

If the merger is completed, you will be entitled to receive $23.00 in cash, without interest and subject to any applicable withholding taxes, for each share of our common stock that you own (unless you have properly exercised your appraisal rights). This amount constitutes (1) a premium of approximately 53 percent to the closing price of our common stock on February 7, 2022, which was the last full trading day before media reports that Mandiant was pursuing a sale; and (2) a premium of approximately 57 percent to Mandiant’s unaffected 10-day volume weighted price as of February 7, 2022.

Mandiant’s Board of Directors, after considering the factors more fully described in the enclosed proxy statement, unanimously: (1) determined that the merger agreement, the merger and the other transactions contemplated by the merger agreement are fair to, advisable and in the best interests of Mandiant and its stockholders; and (2) adopted and approved the merger agreement, the merger and the other transactions contemplated by the merger agreement.

Mandiant’s Board of Directors unanimously recommends that you vote: (1) “FOR” the adoption of the merger agreement; (2) “FOR” the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

The enclosed proxy statement provides detailed information about the special meeting, the merger agreement and the merger, and the other proposals to be considered at the special meeting. A copy of the merger agreement is attached as Annex A to this proxy statement.

The proxy statement also describes the actions and determinations of Mandiant’s Board of Directors in connection with its evaluation of the merger agreement and the merger. Please read the proxy statement and its annexes, including the merger agreement, carefully and in their entirety, as they contain important information.

Even if you plan to attend the special meeting, please sign, date and return, as promptly as possible, the enclosed proxy card (a prepaid reply envelope is provided for your convenience) or grant your proxy

TABLE OF CONTENTS

electronically over the internet or by telephone (using the instructions found on the proxy card). If you attend the special meeting and vote at the special meeting, your vote will revoke any proxy that you have previously submitted. If you fail to return your proxy or to attend the special meeting, your shares will not be counted for purposes of determining whether a quorum is present at the special meeting and will have the same effect as a vote against the adoption of the merger agreement.

If your shares are held through a bank, broker or other nominee, you are considered the “beneficial owner” of shares held in “street name.” If you hold your shares in “street name,” you should instruct your bank, broker or other nominee how to vote your shares in accordance with the voting instruction form provided by your bank, broker or other nominee. Your bank, broker or other nominee cannot vote on any of the proposals to be considered at the special meeting without your instructions. Without your instructions, your shares will not be counted for purposes of a quorum or be voted at the special meeting, and that will have the same effect as voting against the adoption of the merger agreement.

Your vote is very important, regardless of the number of shares that you own.

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

MacKenzie Partners, Inc.
1407 Broadway, 27th Floor
New York, NY 10018
Call toll free: 1 (800) 322-2885
Email: proxy@mackenziepartners.com

On behalf of Mandiant’s Board of Directors, thank you for your support.

Very truly yours,

Kevin R. Mandia
Chief Executive Officer

The accompanying proxy statement is dated [•], 2022, and, together with the enclosed form of proxy card, is first being sent on or about [•], 2022.

TABLE OF CONTENTS

[PRELIMINARY PROXY STATEMENT — SUBJECT TO COMPLETION]

Mandiant, Inc.
11951 Freedom Drive, 6th Floor
Reston, VA 20190

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON [•], 2022

Notice is given that a special meeting of stockholders (which we refer to, together with any adjournment, postponement or other delay thereof, as the “special meeting”) of Mandiant, Inc., a Delaware corporation (which we refer to as “Mandiant”), will be held on [•], 2022, at [•] [a.m./p.m.], Pacific time, for the following purposes:

To consider and vote on the proposal to adopt the Agreement and Plan of Merger (as it may be amended from time to time), dated March 7, 2022, between Google LLC (which we refer to as “Parent”), Dupin Inc., a wholly owned subsidiary of Parent and Mandiant (which we refer to as the “merger agreement”);

To consider and vote on the proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger of Dupin Inc. with and into Mandiant (which we refer to as the “merger”);

To consider and vote on any proposal to adjourn the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting; and

To transact any other business that may properly come before the special meeting.

Only Mandiant stockholders as of the close of business on [•], 2022, are entitled to notice of, and to vote at, the special meeting.

Mandiant stockholders who do not vote in favor of the proposal to adopt the merger agreement will have the right to seek appraisal of the “fair value” of their shares of our common stock (exclusive of any elements of value arising from the accomplishment or expectation of the merger and together with interest (as described in the accompanying proxy statement) to be paid on the amount determined to be “fair value”) in lieu of receiving $23.00 per share in cash if the merger is completed, as determined in accordance with Section 262 of the Delaware General Corporation Law (which is referred to as the “DGCL”). To do so, a Mandiant stockholder must properly demand appraisal before the vote is taken on the merger agreement and comply with all other requirements of the DGCL, including Section 262 of the DGCL, which are summarized in the accompanying proxy statement, and must meet certain other conditions. Section 262 of the DGCL is reproduced in its entirety in Annex B to the accompanying proxy statement and is incorporated in this notice by reference.

TABLE OF CONTENTS

The special meeting will be hosted in a virtual format only online via live webcast. You will not be able to attend the special meeting in person. If your shares are held in your own name in the records of Mandiant’s transfer agent, American Stock Transfer & Trust Company, LLC (which we refer to as “AST”), you will be able to attend and participate in the special meeting online, vote your shares electronically at the special meeting and submit your questions during the special meeting by visiting [•] and entering both the 11-digit control number previously provided to you in your proxy materials and the meeting password. The password for the meeting is [•]. If you are a stockholder of record and you have misplaced your 11-digit control number, please call AST at (800) 937-5449.

If your shares are held in “street name” through a bank, broker or other nominee, you must register in advance in order to attend the special meeting. To register, you must obtain a “legal proxy” from the bank, broker or other nominee that is the record holder of your shares. Then you must submit the legal proxy, along with your name and email address, to AST to receive an 11-digit control number that may be used to access the virtual special meeting website provided above. Requests for registration and submission of legal proxies should be labeled as “Legal Proxy” and must be received by AST no later than 5:00 p.m., Eastern time on [•]. Submit your registration request and legal proxy by: (1) email to proxy@astfinancial.com; (2) facsimile to 718-765-8730; or (3) mail to American Stock Transfer & Trust Company, LLC, Attn: Proxy Tabulation Department, 6201 15th Avenue, Brooklyn, NY 11219. Obtaining a legal proxy may take several days and you are advised to register as far in advance as possible. Once you have obtained your 11-digit control number from AST, please follow the steps set forth in the prior paragraph for stockholders of record to attend the special meeting.

By Order of the Board of Directors,

Kevin R. Mandia
Chief Executive Officer

Dated: [•], 2022

Reston, Virginia

TABLE OF CONTENTS

IMPORTANT INFORMATION

Even if you plan to attend the special meeting, we encourage you to submit your proxy as promptly as possible: (1) over the internet; (2) by telephone; or (3) by signing and dating the enclosed proxy card (a prepaid reply envelope is provided for your convenience). You may revoke your proxy or change your vote at any time before your proxy is voted at the special meeting.

If you are a stockholder of record, voting at the special meeting will revoke any proxy that you previously submitted. If you hold your shares through a bank, broker or other nominee, you must obtain a “legal proxy” from the bank, broker or other nominee that holds your shares in order to vote at the special meeting.

We encourage you to read the accompanying proxy statement and its annexes, including all documents incorporated by reference into the accompanying proxy statement, carefully and in their entirety. If you have any questions concerning the merger, the special meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement, or need help voting your shares, please contact our proxy solicitor:

MacKenzie Partners, Inc.
1407 Broadway, 27th Floor
New York, NY 10018
Call toll free: 1 (800) 322-2885
Email: proxy@mackenziepartners.com

TABLE OF CONTENTS

SUMMARY

Except as otherwise specifically noted in this proxy statement, “Mandiant,” “we,” “our,” “us” and similar words refer to Mandiant, Inc., including, in certain cases, our subsidiaries. Throughout this proxy statement, the “Mandiant Board” refers to Mandiant’s Board of Directors. Throughout this proxy statement, we refer to Google LLC as “Parent” and Dupin Inc. as “Merger Sub.” In addition, throughout this proxy statement we refer to the Agreement and Plan of Merger (as it may be amended from time to time), dated March 7, 2022, between Parent, Merger Sub and Mandiant as the “merger agreement.”

This summary highlights selected information from this proxy statement related to the proposed merger of Merger Sub (a wholly owned subsidiary of Parent) with and into Mandiant. We refer to that transaction as the “merger.”

This proxy statement may not contain all of the information that is important to you. To understand the merger more fully and for a complete description of its legal terms, you should carefully read this proxy statement, including the annexes to this proxy statement and the other documents to which we refer in this proxy statement. You may obtain the information incorporated by reference in this proxy statement without charge by following the instructions in the section of this proxy statement captioned “Where You Can Find More Information.” A copy of the merger agreement is attached as Annex A to this proxy statement. We encourage you to read the merger agreement, which is the legal document that governs the merger, carefully and in its entirety.

Introduction

On March 7, 2022, Mandiant agreed to be acquired by Parent. If the merger is completed, each outstanding share of our common stock (which we refer to as our “common stock”) (subject to certain exceptions) will be converted into the right to receive $23.00 per share in cash, without interest and less any applicable tax withholdings.

Parties Involved in the Merger

Mandiant, Inc.

Mandiant is a global cybersecurity company with a mission to protect our customers from cyber-attacks using innovative technology, intelligence and expertise from the front lines.

Mandiant provides intelligence-based cybersecurity solutions and services that allow organizations to prepare for, prevent, investigate, respond to and remediate cyber-attacks, including attacks that target on-premises, cloud, and critical infrastructure environments.

Our common stock is listed on the Nasdaq Global Select Market (which we refer to as the “Nasdaq”) under the symbol “MNDT.” Mandiant’s corporate offices are located at 11951 Freedom Drive, 6th Floor, Reston, Virginia 20190, and its telephone number is (703) 935-1700.

Google LLC

Parent’s mission is to organize the world’s information and make it universally accessible and useful. Through products and platforms like Search, Maps, Gmail, Android, Google Play, Chrome and YouTube, Parent plays a meaningful role in the daily lives of billions of people and has become one of the most widely-known companies in the world. Parent is a subsidiary of Alphabet Inc. Parent’s address is 1600 Amphitheatre Parkway, Mountain View, California 94043, and its telephone number is (650) 253-0000.

Dupin Inc.

Merger Sub, a Delaware corporation and a wholly owned subsidiary of Parent, was formed on February 28, 2022 solely for the purpose of engaging in the transactions contemplated by the merger agreement. Merger Sub has not engaged in any business activities other than in connection with the transactions contemplated by the merger agreement. Upon completion of the merger of Merger Sub with and into Mandiant, Merger Sub will cease to exist. Merger Sub’s address is 1600 Amphitheatre Parkway, Mountain View, California 94043, and its telephone number is (650) 253-0000.

TABLE OF CONTENTS

Effects of the Merger

Upon the terms and subject to the conditions of the merger agreement, and in accordance with the Delaware General Corporation Law (which we refer to as the “DGCL”), at the effective time of the merger: (1) Merger Sub will merge with and into Mandiant; (2) the separate existence of Merger Sub will cease; and (3) Mandiant will continue as the surviving corporation in the merger and as a wholly owned subsidiary of Parent. Throughout this proxy statement, we use the term “surviving corporation” to refer to Mandiant as the surviving corporation following the merger.

As a result of the merger, Mandiant will cease to be a publicly traded company. If the merger is completed, you will not own any shares of capital stock of the surviving corporation.

The time at which the merger becomes effective (which we refer to as the “effective time of the merger”) will occur upon the filing of a certificate of merger with, and acceptance of that certificate by, the Secretary of State of the State of Delaware (or at a later time as Mandiant, Parent and Merger Sub may agree and specify in such certificate of merger).

Per Share Price

Upon the terms and subject to the conditions of the merger agreement, at the effective time of the merger, each outstanding share of our common stock (other than shares of our common stock that are (1) held by Mandiant as treasury stock, (2) owned by Parent or Merger Sub, (3) owned by any direct or indirect wholly owned subsidiary of Parent or Merger Sub, in each case, as of immediately prior to the effective time of the merger or (4) held by stockholders who have neither voted in favor of the adoption of the merger agreement nor consented thereto in writing and properly and validly exercised their statutory rights of appraisal in accordance with Section 262 of the DGCL (which shares of our common stock we refer to collectively as the “excluded shares”)) will be cancelled and automatically converted into the right to receive $23.00 in cash, without interest and less any applicable withholding taxes. We refer to this amount as the “per share price.”

On the closing date of the merger or the first business day following the closing date of the merger, a sufficient amount of cash will be deposited with a designated payment agent to pay the aggregate per share price. Once our stockholders have provided the payment agent with any documentation required by the payment agent, the payment agent will pay the stockholder the appropriate portion of the aggregate per share price in exchange for the shares of our common stock held by that stockholder. For more information, see the section of this proxy statement captioned “The Merger Agreement — Payment Agent, Exchange Fund, and Exchange and Payment Procedures.”

After the merger is completed, you will have the right to receive the per share price for each share of our common stock that you own, but you will no longer have any rights as a stockholder (except that our stockholders who properly and validly exercise and perfect, and do not validly withdraw or otherwise lose, their appraisal rights will have the right to receive a payment for the “fair value” of their shares as determined pursuant to an appraisal proceeding as contemplated by the DGCL, as described in the section of this proxy statement captioned “The Merger — Appraisal Rights”).

The Special Meeting

Date, Time and Place

A special meeting of our stockholders will be held on [•], 2022, at [•] [a.m./p.m.], Pacific time. You may attend the special meeting via a live interactive webcast on the internet at [•]. We refer to the special meeting, and any adjournment, postponement or other delay of the special meeting, as the “special meeting.” You will need the control number found on your proxy card or voting instruction form in order to participate in the special meeting (including voting your shares). We elected to use a virtual meeting given the current public health implications of COVID-19 and our desire to promote the health and welfare of our stockholders, as well as our positive experiences with virtual meetings.

TABLE OF CONTENTS

Purpose

At the special meeting, we will ask stockholders to vote on proposals to: (1) adopt the merger agreement; (2) approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) adjourn the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Record Date; Shares Entitled to Vote

You are entitled to vote at the special meeting if you owned shares of our common stock or shares of our convertible preferred stock as of the close of business on [•], 2022 (which we refer to as the “record date”). For each share of our common stock (including on an as-converted basis) that you owned as of the close of business on the record date, you will have one vote on each matter submitted for a vote at the special meeting.

Quorum

As of the record date, there were [•] shares of our common stock outstanding and entitled to vote at the special meeting. As of the record date, there were 400,000 shares of our convertible preferred stock issued and outstanding, which are convertible into, in the aggregate, at the option of the holder [•] shares of our common stock, and entitled to vote on an as-converted-into-common-stock basis at the special meeting. The holders of a majority of the shares of the stock issued and outstanding and entitled to vote, present in person or represented by proxy, shall constitute a quorum.

Required Vote

The proposals to be voted on at the special meeting require the following votes:

•

Proposal 1: Approval of the proposal to adopt the merger agreement requires the affirmative vote of the holders of a majority of the shares of our common stock and shares of our convertible preferred stock outstanding as of the record date, voting together as a single class on an as-converted basis.

•

Proposal 2: Approval of the proposal to approve the compensation that will or may become payable to our named executive officers in connection with the merger requires the affirmative vote of a majority of the voting power of the shares of our common stock and shares of our convertible preferred stock present in person or represented by proxy at the special meeting and entitled to vote on the proposal, voting together as a single class on an as-converted basis. This vote will be on a non-binding, advisory basis.

•

Proposal 3: Approval of the proposal to adjourn the special meeting to a later date or dates to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting requires the affirmative vote of a majority of the voting power of the shares of our common stock and shares of our convertible preferred stock present in person or represented by proxy at the special meeting and entitled to vote on the proposal, voting together as a single class on an as-converted basis.

Voting and Proxies

Any stockholder of record entitled to vote at the special meeting may vote in any of the following ways:

•

by proxy, by returning a signed and dated proxy card (a prepaid reply envelope is provided for your convenience);

•

by proxy, by granting a proxy electronically over the internet or by telephone (using the instructions found on the proxy card); or

•

by attending the special meeting and voting at the special meeting using the link on the special meeting website.

TABLE OF CONTENTS

If you are a stockholder of record, you may change your vote or revoke your proxy at any time before it is voted at the special meeting by (1) signing another proxy card with a later date and returning it prior to the special meeting; (2) submitting a new proxy electronically over the internet or by telephone after the date of the earlier submitted proxy; (3) delivering a written notice of revocation to our Corporate Secretary; or (4) attending the special meeting and voting at the special meeting.

If you are a beneficial owner and hold your shares of our common stock in “street name” through a bank, broker or other nominee, you should instruct your bank, broker or other nominee on how you wish to vote your shares of our common stock using the instructions provided by your bank, broker or other nominee. Under applicable stock exchange rules, banks, brokers or other nominees have the discretion to vote on routine matters, but not on non-routine matters. The proposals to be considered at the special meeting are all non-routine matters, and banks, brokers and other nominees cannot vote on these proposals without your instructions. Therefore, it is important that you cast your vote or instruct your bank, broker or nominee on how you wish to vote your shares.

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

Recommendation of the Mandiant Board and Reasons for the Merger

The Mandiant Board, after considering various factors described in the section of this proxy statement captioned “The Merger — Recommendation of the Mandiant Board and Reasons for the Merger,” unanimously: (1) determined that the merger agreement, the merger and the other transactions contemplated by the merger agreement are fair to, advisable and in the best interests of Mandiant and its stockholders; and (2) adopted and approved the merger agreement, the merger and the other transactions contemplated by the merger agreement.

The Mandiant Board unanimously recommends that you vote: (1) “FOR” the adoption of the merger agreement; (2) “FOR” the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Opinion of Goldman Sachs & Co. LLC

Goldman Sachs & Co. LLC (which we refer to as “Goldman Sachs”) rendered to the Mandiant Board its oral opinion, subsequently confirmed in its written opinion dated March 7, 2022, to the effect that, as of the date of the written opinion and based upon and subject to the factors and assumptions set forth therein, the $23.00 in cash per share of our common stock to be paid to the holders (other than Parent and its affiliates) of shares of our common stock pursuant to the merger agreement, was fair from a financial point of view to the holders of such shares.

The full text of the written opinion of Goldman Sachs, dated March 7, 2022, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached to this proxy statement as Annex C. The summary of Goldman Sachs’ opinion contained in this proxy statement is qualified in its entirety by reference to the full text of Goldman Sachs’ written opinion. Goldman Sachs provided advisory services and its opinion for the information and assistance of the Mandiant Board in connection with its consideration of the merger. The Goldman Sachs opinion is not a recommendation as to how any holder of our common stock should vote with respect to the merger or any other matter.

Treatment of Equity Awards in the Merger

The merger agreement provides that Mandiant’s equity awards that are outstanding immediately prior to the effective time of the merger will be treated in the following manner in connection with the merger.

TABLE OF CONTENTS

For more information, see the section of this proxy statement captioned “The Merger Agreement — Conversion of Shares — Equity Awards; ESPP.”

Treatment of Mandiant Restricted Stock Units

•

Each restricted stock unit (which we refer to as a “Mandiant restricted stock unit”) that is vested, or which is unvested and held by a non-employee director of the Mandiant Board, in each case that is outstanding as of the effective time of the merger (which we collectively refer to as a “vested Mandiant restricted stock unit”), will accelerate vesting in full (to the extent not already vested) and be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such vested Mandiant restricted stock unit; and (2) the total number of shares of our common stock then-subject to such vested Mandiant restricted stock unit. This amount (less any required withholding and other taxes) will be paid to the applicable holder promptly following the effective time of the merger.

•

Each Mandiant restricted stock unit that is unvested as of the effective time of the merger that is held by an individual who is providing services to Mandiant or its subsidiaries immediately prior to the effective time (which we refer to as an “unvested Mandiant restricted stock unit”) will be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such unvested Mandiant restricted stock unit; and (2) the total number of shares of our common stock then-subject to such unvested Mandiant restricted stock unit. Such cash amount will (1) vest and become payable (less any required withholding and other taxes) in accordance with the vesting schedule applicable to the corresponding unvested Mandiant restricted stock unit immediately prior to the effective time of the merger subject to such holder’s continued service with Parent and its affiliates through the applicable vesting dates; and (2) be subject to the terms and conditions of any related agreements containing the payment, vesting conditions and other terms by which such amount is payable (which we refer to as the “unvested payment plan”).

•

All other Mandiant restricted stock units not described above that are outstanding immediately prior to the effective time of the merger will be canceled for no consideration.

Treatment of Mandiant Performance-Based Awards

•

Each Mandiant performance-based restricted stock unit (which we refer to as a “Mandiant PSU”) (including any portion thereof) for which the performance period has been completed at or prior to the effective time of the merger that is outstanding as of the effective time of the merger (which we refer to as a “completed Mandiant PSU”) will be canceled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the per share price and (2) the total number of shares of our common stock then-subject to such completed Mandiant PSU based on the actual achievement of all relevant performance goals (which we refer to as the “completed Mandiant PSU consideration”), with such completed Mandiant PSU consideration vesting in accordance with the service-based vesting schedule applicable to such completed Mandiant PSU immediately prior to the effective time of the merger and subject to the terms of the unvested payment plan.

•

At the effective time of the merger, each Mandiant PSU (including any portion thereof) for which the performance period has not been completed at or prior to the effective time of the merger that is outstanding immediately prior to the effective time of the merger (which we refer to as an “uncompleted Mandiant PSU”) will be canceled and converted into a right to receive, an amount in cash, without interest, equal to the product of (1) the per share price and (2) the total number of shares of our common stock then-subject to such uncompleted Mandiant PSU assuming maximum level of achievement of all relevant performance goals (which we refer to as the “uncompleted Mandiant PSU consideration”), with such uncompleted Mandiant PSU consideration vesting in accordance with the service-based vesting schedule applicable to such uncompleted Mandiant PSU immediately prior to the effective time of the merger and subject to the terms of the unvested payment plan.

TABLE OF CONTENTS

Treatment of Mandiant Options

•

Each Mandiant stock option (which we refer to as a “Mandiant option”) that is outstanding and unexercised as of immediately prior to the effective time of the merger will accelerate vesting in full and be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess, if any, of the per share price over the exercise price per share of such Mandiant option, and (2) the number of shares of our common stock then issuable upon exercise in full of such Mandiant option. This amount (less any required withholding and other taxes) will be paid to the applicable holder promptly following the effective time of the merger.

•

Any Mandiant option, whether vested or unvested, with an exercise price per share that is equal to or greater than the per share price will be canceled without any cash payment being made in respect thereof.

Treatment of the ESPP

•

No further offering period or purchase period will commence pursuant to our Amended and Restated 2013 Employee Stock Purchase Plan, as amended (which we refer to as the “ESPP”) following the closing date of the merger. The ESPP will be terminated immediately prior to and effective as of the effective time of the merger (subject to consummation of the merger).

•

Any offering period or purchase period under the ESPP that otherwise would be in progress as of the effective time of the merger will be terminated no later than 10 business days prior to the effective time of the merger.

•

We will apply any funds within each ESPP participant’s account to the purchase of whole shares of our common stock in accordance with the terms of the ESPP. These shares will be deposited into the applicable participant’s account and will treated in the same manner as any other outstanding share of common stock in connection with the consummation of the merger. Any amounts not used for the purchase of shares of our common stock will be refunded.

Employee Benefits

From and after the effective time of the merger, all of our arrangements providing for compensation or benefits to our service providers (which we refer to as “Mandiant benefit plans”) will be honored in accordance with their terms as in effect immediately prior to the effective time of the merger. However, subject to the below, Parent or the surviving corporation will be permitted to amend or terminate any such Mandiant benefit plans in accordance with their terms or if otherwise required pursuant to applicable law.

We refer to each individual who is our employee or an employee of any of our subsidiaries immediately prior to the effective time of the merger and continues to be an employee of Parent or one of its subsidiaries (including the surviving corporation) immediately following the effective time of the merger as a “continuing employee.”

For one year following the effective time of the merger, each continuing employee generally will receive (i) base salary and annual cash target bonus opportunities that are substantially comparable in the aggregate to the base salary and annual cash target bonus opportunities provided to such continuing employee as of immediately prior to the effective time of the merger and (ii) health and welfare benefits that are substantially similar to those health and welfare benefits that are provided to similarly situated employees of Parent or its subsidiaries. However, no defined benefit pension, post-retirement medical, equity-based, retention, change-in-control, severance or other special or non-recurring compensation or benefits provided to continuing employees prior to the effective time of the merger will be taken into account for the foregoing.

Continuing employees generally will receive credit for all service with us and our subsidiaries prior to the effective time of the merger and with Parent, the surviving corporation, and any of their subsidiaries on or after the effective time of the merger, for purposes of eligibility to participate, vesting and entitlement to benefits where length of service is relevant (including for purposes of vacation accrual and severance pay entitlement) under each of the comparable employee benefit plans, programs and policies of Parent, the surviving corporation or the relevant subsidiary, as applicable (which we refer to as “new plans”), in which such continuing employee becomes a participant. However, such recognition of service will not apply to the

TABLE OF CONTENTS

extent it would result in a duplication of benefits or for purposes of (A) any equity or equity-based plans (including any entitlement to equity acceleration in connection with retirement), (B) any plan that provides retiree welfare benefits, (C) benefit accruals or participation eligibility under any defined benefit pension plan or plan providing post-retirement pension plan benefits other than as required by applicable law outside of the United States or (D) any plan, program or arrangement under which similarly situated employees of Parent and its subsidiaries do not receive credit for prior service or that is grandfathered or frozen.

Additionally, with respect to each new plan that is an “employee welfare benefit plan” (as that term is defined in Section 3(1) of ERISA) (other than the Mandiant benefit plans) for the purpose of providing medical, surgical or hospital care or benefits for the benefit of any continuing employees, Parent will use commercially reasonable efforts so that generally (A) all waiting periods, pre-existing conditions or limitations, physical examination requirements, evidence of insurability requirements and actively-at-work or similar requirements of such new plan generally will be waived and (B) any eligible expenses incurred by a continuing employee and his or her covered dependents during the plan year that includes the closing date will be given full credit pursuant to such new plan for purposes of satisfying all deductible, co-payments, coinsurance, offset and maximum out-of-pocket requirements applicable to such continuing employee and his or her covered dependents for the applicable plan year as if such amounts had been paid in accordance with such new plan.

For more information, see the section of this proxy statement captioned “The Merger Agreement — Employee Benefits.”

Interests of Mandiant’s Directors and Executive Officers in the Merger

•

For our executive officers, the treatment of their outstanding equity-based awards of Mandiant restricted stock units, Mandiant PSUs and Mandiant options, and outstanding rights to purchase shares or our common stock under the ESPP.

•

For our non-employee directors, the accelerated vesting, at or immediately prior to the effective time of the merger, of Mandiant restricted stock units and Mandiant options.

•

For our executive officers, the entitlement to receive certain severance payments and benefits (including accelerated vesting of equity-based awards) in the event of certain qualifying terminations of employment in connection with the merger.

•

For Kevin Mandia, our chief executive officer, the entitlement to receive cash and equity incentives under a new offer letter with Parent and a voting agreement with Parent and Mandiant, which obligates Mr. Mandia to vote certain of his shares of Mandiant’s common stock in favor of the adoption of the merger agreement and against any competing transaction.

•

The continued indemnification and insurance coverage for our directors and executive officers from the surviving corporation and Parent under the terms of the merger agreement.

A detailed description of these interests is included in the section of this proxy statement captioned “The Merger — Interests of Mandiant’s Directors and Executive Officers in the Merger.”

Appraisal Rights

TABLE OF CONTENTS

lose their rights to appraisal will be entitled to seek appraisal of their shares in connection with the merger under Section 262 of the DGCL. This means that these stockholders will be entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash for the “fair value” of their shares of our common stock, exclusive of any elements of value arising from the accomplishment or expectation of the merger, together with (unless the Delaware Court of Chancery in its discretion determines otherwise for good cause shown) interest on the amount determined by the Delaware Court of Chancery to be the fair value from the effective date of the merger through the date of payment of the judgment at a rate of five percent over the Federal Reserve discount rate (including any surcharge) as established from time to time during the period between the effective date of the merger and the date of payment of the judgment, compounded quarterly (except that, if at any time before the entry of judgment in the proceeding, the surviving corporation makes a voluntary cash payment to stockholders seeking appraisal, interest will accrue thereafter only upon the sum of (1) the difference, if any, between the amount so paid and the fair value of the shares as determined by the Delaware Court of Chancery; and (2) interest theretofore accrued, unless paid at that time). The surviving corporation is under no obligation to make such voluntary cash payment prior to such entry of judgment. Due to the complexity of the appraisal process, stockholders who wish to seek appraisal of their shares are encouraged to seek the advice of legal counsel with respect to the exercise of appraisal rights.

Stockholders considering seeking appraisal should be aware that the fair value of their shares as determined pursuant to Section 262 of the DGCL could be more than, the same as or less than the value of the consideration that they would receive pursuant to the merger agreement if they did not seek appraisal of their shares.

Only a stockholder of record may submit a demand for appraisal. To exercise appraisal rights, the stockholder of record must (1) submit a written demand for appraisal to Mandiant before the vote is taken on the proposal to adopt the merger agreement; (2) not vote, in person or by proxy, in favor of the proposal to adopt the merger agreement; (3) continue to hold the subject shares of our common stock of record through the effective time of the merger; and (4) strictly comply with all other procedures for exercising appraisal rights under the DGCL. The failure to follow exactly the procedures specified under the DGCL may result in the loss of appraisal rights. In addition, the Delaware Court of Chancery will dismiss appraisal proceedings in respect of Mandiant unless certain conditions are satisfied by the stockholders seeking appraisal, as described further below. The requirements under Section 262 of the DGCL for exercising appraisal rights are described in further detail in this proxy statement, which description is qualified in its entirety by Section 262 of the DGCL, the relevant section of the DGCL regarding appraisal rights, a copy of which is attached as Annex B to this proxy statement. If you hold your shares of our common stock through a bank, broker or other nominee and you wish to exercise appraisal rights, you should consult with your bank, broker or other nominee to determine the appropriate procedures for the making of a demand for appraisal on your behalf by your bank, broker or other nominee.

Material U.S. Federal Income Tax Consequences of the Merger

For U.S. federal income tax purposes, the receipt of cash by a U.S. Holder (as defined in the section of this proxy statement captioned “The Merger — Material U.S. Federal Income Tax Consequences of the Merger”) in exchange for such U.S. Holder’s shares of our common stock in the merger generally will result in the recognition of gain or loss in an amount measured by the difference, if any, between the amount of cash that such U.S. Holder receives in the merger and such U.S. Holder’s adjusted tax basis in the shares of our common stock surrendered in the merger.

A Non-U.S. Holder (as defined in the section of this proxy statement captioned “The Merger — Material U.S. Federal Income Tax Consequences of the Merger”) generally will not be subject to U.S. federal income tax with respect to the exchange of our common stock for cash in the merger unless such Non-U.S. Holder has certain connections to the United States, but may be subject to backup withholding tax unless the Non-U.S. Holder complies with certain certification procedures or otherwise establishes a valid exemption from backup withholding tax.

For more information, see the section of this proxy statement captioned “The Merger — Material U.S. Federal Income Tax Consequences of the Merger.” Stockholders should consult their own tax advisors concerning the U.S. federal income tax consequences relating to the merger in light of their particular

TABLE OF CONTENTS

circumstances and any consequences arising under U.S. federal non-income tax laws or the laws of any state, local or non-U.S. taxing jurisdiction.

Regulatory Approvals Required for the Merger

Under the merger agreement, the merger cannot be completed until the waiting period (and any extensions thereof, if any) applicable to the merger under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (which we refer to as the “HSR Act”) has expired or otherwise been terminated.

The initial waiting period under the HSR Act is set to expire at 11:59 p.m., Eastern time, on April 20, 2022.

The merger is also subject to clearances, consents, approvals and the waiting periods applicable to the merger under certain foreign antitrust laws and foreign investment (which we refer to as “FDI”) laws. Antitrust and FDI approvals of the merger are required in various jurisdictions throughout Europe, the Middle East and Asia.

Financing of the Merger

Parent’s and Merger Sub’s obligations under the merger agreement are not conditioned on the receipt or availability of any funds, or subject to any financing condition. Parent intends to finance the transaction using its cash on hand and has represented to us in the merger agreement that it has sufficient cash resources to pay the aggregate merger consideration.

Mandiant also has outstanding $600 million in aggregate principal amount of 0.875% convertible senior notes due 2024 (which we refer to as the “2024 Notes”), $23.4 million in aggregate principal amount of 1.000% convertible Series A senior notes due 2035 (which we refer to as the “Series A 2035 Notes”) and $460 million in aggregate principal amount of 1.625% convertible Series B senior notes due 2035 (which we refer to as the “Series B 2035 Notes,” and, together with the 2024 Notes and Series A 2035 Notes, the “Convertible Notes”). On the closing date of the merger, each series of Convertible Notes will be convertible into the merger consideration at the then applicable conversion rate for the relevant series of Convertible Notes. Mandiant will be required to make an offer to repurchase each series of Convertible Notes at 100 percent of their principal amount plus accrued and unpaid interest to, but excluding, the applicable fundamental change repurchase date (as defined in the applicable convertible notes indenture). The Series A 2035 Notes are also redeemable at the option of Mandiant, and after June 1, 2022, the Series B 2035 Notes will be redeemable at the option of Mandiant, in each case at 100 percent of their principal amount plus accrued and unpaid interest, if any, to, but excluding, the applicable redemption date (as defined in the applicable convertible notes indenture). Under the merger agreement, Mandiant has agreed to cooperate with Parent in the event that Parent seeks to launch a tender offer with respect to any or all of the Convertible Notes. In connection with the issuance of the 2024 Notes, Mandiant entered into capped call transactions (which we refer to as the “capped call transactions”) with certain financial institutions (which we refer to as the “option counterparties”). The capped call transactions were expected by Mandiant to reduce the potential dilution to Mandiant’s common stock upon any conversion of the 2024 Notes and/or to offset any cash payments that Mandiant would be required to make in excess of the principal amount of such converted 2024 Notes, as the case may be, with such reduction and/or offset subject to a cap set forth in the capped call transactions. In order to hedge the risks of the option counterparties under or in respect of the capped call transactions, the option counterparties or their respective affiliates from time to time enter into or unwind various derivative transactions with respect to Mandiant’s common stock and/or purchase or sell Mandiant’s common stock or other securities issued by Mandiant in secondary market transactions.

Pursuant to the merger agreement, Parent has the right to direct Mandiant to effect an early termination and cash settlement of all obligations in respect of the capped call transactions. Pursuant to the merger agreement, Mandiant has agreed that, except as directed by Parent, Mandiant will not exercise any option or make any election under, or amend, modify, supplement, negotiate any adjustment to or obtain any waiver of, or novate, accelerate, liquidate, terminate early, cancel or otherwise settle, any of the capped call transactions.

In connection with the issuance of the Series A 2035 Notes and the Series B 2035 Notes, Mandiant entered into two privately negotiated prepaid share forward transactions (which we refer to as the “prepaid

TABLE OF CONTENTS

share forward transactions”) with one of the initial purchasers of the 2035 Notes (which we refer to as the “forward counterparty”). The prepaid share forward transaction entered into in connection with the issuance of the Series A 2035 Notes was fully settled on June 3, 2020. The prepaid share forward transaction entered into in connection with the issuance of the Series B 2035 Notes was intended by Mandiant to facilitate privately negotiated derivative transactions pursuant to which investors in the Series B 2035 Notes are able to hedge their investment in the Series B 2035 Notes. It is scheduled to settle on or about June 1, 2022.

Pursuant to the merger agreement, Mandiant has agreed that, except for the settlement on June 1, 2022 of the prepaid share forward transaction in accordance with its terms, Mandiant will not exercise any option or make any election under, or amend, modify, supplement, negotiate any adjustment to or obtain any waiver of, or novate, accelerate, liquidate, terminate early, cancel or otherwise settle, such prepaid share forward transaction.

The Voting Agreements

In connection with entering into the merger agreement, on March 7, 2022, following the Mandiant Board’s approval thereof, Mandiant’s convertible preferred stockholders, Blackstone Delta Lower Holdings DE L.P. and, BTO FD Delta Holdings DE L.P. (which we refer to as “Blackstone”), ClearSky Security Fund I LLC and ClearSky Power & Technology Fund II LLC (which we refer to as “ClearSky”), and Mr. Mandia, in each case in their capacities as stockholders of Mandiant, entered into voting agreements (which we refer to as the “voting agreements”) with Parent and Mandiant. The voting agreements obligate (A) the applicable stockholders to vote their respective shares of our common stock and convertible preferred stock (1) in favor of the adoption of the merger agreement and the approval of the transactions contemplated thereby and by the other transaction documents, including the merger, (2) in favor of any proposal to adjourn or postpone such meeting of Mandiant’s stockholders to a later date if there are not sufficient votes to adopt the merger agreement, (3) against any action or proposal in favor of an acquisition proposal, without regard to the terms of such acquisition proposal, and (4) against any action, proposal, transaction or agreement that would reasonably be likely to prevent, materially impede or materially delay the merger or the other transactions contemplated by the merger agreement, and (B) in the case of the convertible preferred stockholders, the applicable convertible preferred stockholders to take all steps necessary to convert all of their shares of Mandiant’s convertible preferred stock into shares of common stock, including delivering to Mandiant a conversion notice in respect of their convertible preferred stock concurrently with the execution and delivery of the voting agreements, prior to the effective time of the merger and, in the case of Blackstone, prior to any exercise of remedies by their lenders with respect to such shares, if earlier. The voting agreements terminate upon the earliest to occur of (1) the termination of the merger agreement in accordance with its terms; (2) the effective time of the merger; or (3) the entry into any amendment or modification to, or waiver of Mandiant’s rights under, the merger agreement that (a) results in a decrease in, change in the composition of, or otherwise adversely affects the merger consideration, (b) extends the termination date (except as contemplated by the merger agreement) or (c) modifies in any material respect Article II or Article VII of the merger agreement in a manner that is adverse to Mandiant’s stockholders without the prior written consent of the stockholders party to the voting agreements.

As of the record date, the voting agreements cover approximately [•] percent of our common stock (on an as-converted basis) in the aggregate. For more information, please see the section of this proxy statement captioned “The Merger — The Voting Agreements.”

Conversion of Convertible Preferred Stock

Mandiant has agreed to cooperate with the holders of the shares of its convertible preferred stock to facilitate and enable their compliance with their obligations under the voting agreements to convert their shares of Mandiant’s convertible preferred stock into Mandiant’s common stock and accept their optional conversion notices (as referenced in the voting agreements) on the terms set forth in the voting agreements, and accept, prepare, execute and deliver any such additional notices, documents and instruments required on the part of Mandiant, so that all of the shares of Mandiant’s convertible preferred stock for which optional conversion notices have been validly submitted are converted into Mandiant’s common stock in advance of the effective time of the merger and converted into the right to receive the per share price in accordance with the merger agreement.

TABLE OF CONTENTS

No Solicitation of Other Acquisition Offers

Beginning on the date of the merger agreement and continuing until the effective time of the merger (or the earlier termination of the merger agreement), Mandiant has agreed to cease and cause to be terminated any activities, discussions or negotiations with, and terminate any data room access of, any person and its representatives relating to an acquisition proposal.

Under the terms of the merger agreement, from the date of the merger agreement until the effective time of the merger (or the earlier termination of the merger agreement), Mandiant has agreed that it will not, and will cause its subsidiaries and their respective directors and executive officers not to, and it will not authorize, and will use its reasonable best efforts to cause, its or its subsidiaries’ employees, consultants and other representatives to not, directly or indirectly:

•

solicit, initiate, propose or induce the making, submission or announcement of, or knowingly encourage, facilitate or assist, any offer, inquiry, indication of interest or proposal that constitutes, or would reasonably be expected to lead to, an acquisition proposal;

•

furnish to any person or group (other than Parent, Merger Sub or any of their respective representatives) any non-public information relating to Mandiant or any of its subsidiaries or afford to any person or group (other than Parent, Merger Sub or any of their respective representatives) access to the business, properties, assets, books, records or other non-public information, or to any personnel, of Mandiant or any of its subsidiaries, in any such case in connection with any acquisition proposal or with the intent to induce the making, submission or announcement of, or to knowingly encourage, facilitate or assist, an acquisition proposal or the making of any offer, inquiry, indication of interest or proposal that constitutes or would reasonably be expected to lead to an acquisition proposal;

•

participate, or engage in discussions or negotiations, with any person or group with respect to an acquisition proposal or with respect to any inquiries from third persons about making an offer, indication of interest or proposal relating to an acquisition proposal;

•

approve, endorse or recommend any offer, inquiry, indication of interest or proposal that constitutes, or would reasonably be expected to lead to, an acquisition proposal;

•

enter into any letter of intent, memorandum of understanding, merger agreement, acquisition agreement or other contract relating to an acquisition transaction, other than a customary confidentiality agreement containing terms no less restrictive to the counterparty than the terms contained in the confidentiality agreement between Mandiant and Parent (we refer to any of these as an “alternative acquisition agreement”); or

•

authorize or commit to do any of the foregoing.

However, prior to the adoption of the merger agreement by our stockholders, Mandiant and the Mandiant Board (or a committee thereof) may, directly or indirectly through one or more of their representatives (including Mandiant’s financial advisor), following the execution and delivery of a customary confidentiality agreement, (1) participate or engage in discussions or negotiations with; (2) furnish any non-public information relating to Mandiant or any of its subsidiaries to; or (3) afford access to the business, properties, assets, books, records or other non-public information or to any personnel, of Mandiant or any of its subsidiaries to, in each case, any person or group or their respective representatives that has made, renewed or delivered to Mandiant a bona fide written acquisition proposal after the date of the merger agreement that was not solicited in material breach of the applicable restrictions but only if the Mandiant Board has determined in good faith (after consultation with its financial advisor and outside legal counsel) that (1) such acquisition proposal either constitutes a superior proposal or would be reasonably likely to lead to a superior proposal; and (2) the failure to take such actions would be reasonably expected to be inconsistent with its fiduciary duties pursuant to applicable law. From the date of the merger agreement to the effective time of the merger (or, if earlier, the termination of the merger agreement), Mandiant has agreed that it will prior to or contemporaneously make available to Parent and its representatives any non-public information concerning Mandiant and its subsidiaries that is provided to any such person or its representatives

TABLE OF CONTENTS

that was not previously made available to Parent or its representatives. For more information, see the section of this proxy statement captioned “The Merger Agreement — No Solicitation of Other Acquisition Offers.”

Mandiant is not entitled to terminate the merger agreement to enter into an agreement for a superior proposal unless it complies with certain procedures in the merger agreement, including engaging in good faith negotiations with Parent during a specified period. If Mandiant terminates the merger agreement in order to accept a superior proposal from a third party it must pay a termination fee to Parent. For more information, see the section of this proxy statement captioned “The Merger Agreement — The Mandiant Board’s Recommendation; Board Recommendation Change.”

Change in the Mandiant Board’s Recommendation

The Mandiant Board may not withdraw its recommendation that our stockholders adopt the merger agreement or take certain similar actions other than, under certain circumstances, if it (or a committee of the Mandiant Board) determines in good faith, after consultation with its financial advisor and outside legal counsel, that failure to do so would result in a breach of the Mandiant Board’s fiduciary duties pursuant to applicable law and the Mandiant Board (or a committee thereof) complies with certain procedures in the merger agreement including engaging in good faith negotiations with Parent during a specified period. If the merger agreement is terminated because the Mandiant Board withdraws its recommendation that our stockholders adopt the merger agreement, then Mandiant must pay a termination fee to Parent. For more information, see the section of this proxy statement captioned “The Merger Agreement — The Mandiant Board’s Recommendation; Board Recommendation Change.”

Conditions to the Closing of the Merger

The obligations of Parent, Merger Sub and Mandiant, as applicable, to consummate the merger are subject to the satisfaction or waiver (where permitted by applicable law) of certain conditions, including the following:

•

the adoption of the merger agreement by the requisite affirmative vote of our stockholders;

•

the expiration or termination of the waiting period, if any, applicable to the merger and the conversion of the convertible preferred stock of Mandiant pursuant to the HSR Act;

•

receipt of all antitrust and FDI approvals, clearances and consents and expirations of waiting periods relating to the merger and the conversion of the convertible preferred stock of Mandiant in various jurisdictions throughout Europe, the Middle East and Asia; and

•

the absence of any temporary restraining order, preliminary or permanent injunction or other judgment or order issued by any court of competent jurisdiction or other legal or regulatory restraint or prohibition preventing the consummation of the merger or the conversion of the convertible preferred stock of Mandiant, any action taken by any governmental authority of competent jurisdiction or any law enacted, entered, enforced or deemed applicable to the merger or the conversion of the convertible preferred stock of Mandiant, that, in each case, prevents, materially restrains or materially impairs the consummation of the merger or the conversion of the convertible preferred stock of Mandiant (we refer to any such order, injunction, judgment, restraint, prohibition, action or law as, a “Restraint”).

In addition, the obligations of Parent and Merger Sub to consummate the merger are subject to the satisfaction or waiver (where permitted by applicable law) of each of the following additional conditions, any of which may be waived exclusively by Parent:

•

the accuracy of the representations and warranties of Mandiant in the merger agreement, subject to applicable materiality or other qualifiers, as of the date of the merger agreement and as of the closing date of the merger (or as of the date as of which such representation or warranty was specifically made);

•

Mandiant having performed and complied in all material respects with all covenants and obligations under the merger agreement required to be performed and complied with by it at or prior to the closing of the merger;

TABLE OF CONTENTS

•

the absence of any Company Material Adverse Effect (as defined in the section of this proxy statement captioned “The Merger Agreement — Representations and Warranties”) having occurred since the date of the merger agreement;

•

the receipt by Parent and Merger Sub of a customary closing certificate of Mandiant; and

•

no order arising under any antitrust or FDI law and no antitrust or FDI law having been issued, enacted, rendered, promulgated, enforced, formally deemed applicable or formally asserted by any governmental authority imposing a remedial action on any of the parties in connection with the merger or the conversion of the convertible preferred stock of Mandiant.

In addition, the obligations of Mandiant to consummate the merger are subject to the satisfaction or waiver (where permitted by applicable law) of each of the following additional conditions, any of which may be waived exclusively by Mandiant:

•

the accuracy of the representations and warranties of Parent and Merger Sub in the merger agreement, subject to applicable materiality or other qualifiers, as of the date of the merger agreement and as of the closing date of the merger (or as of the date as of which such representation or warranty was specifically made);

•

Parent and Merger Sub having performed and complied in all material respects with all covenants and obligations under the merger agreement required to be performed and complied by Parent and Merger Sub prior to the closing of the merger; and

•

the receipt by Mandiant of a customary closing certificate of Parent and Merger Sub.

Termination of the Merger Agreement

The merger agreement may be terminated at any time prior to the effective time of the merger, whether before or after the adoption of the merger agreement by our stockholders (except as otherwise provided in the merger agreement), in the following ways:

•

by mutual written agreement of Mandiant and Parent;

•

by either Mandiant or Parent if:

•

any Restraint has become final and non-appealable except that the right to terminate will not be available to any party whose action or failure constitutes a material breach of the merger agreement and has been the primary cause of, or primarily resulted in, such Restraint or in such Restraint becoming final and non-appealable or failing to be removed;

•

the merger has not been consummated by 11:59 p.m., Pacific time, on March 7, 2023 (which we refer to as the “termination date”), subject to two automatic extensions to June 7, 2023, and September 7, 2023, if certain conditions to closing are not met by these dates, except that a party may not terminate the merger agreement pursuant to this provision if such party’s action or failure to act constitutes a material breach of the merger agreement and has been the primary cause of, or primarily resulted in the failure of the effective time of the merger to have occured prior to the termination date; or

•

our stockholders do not adopt the merger agreement at the special meeting;

•

by Mandiant if:

•

subject to a 45-day cure period, Parent or Merger Sub has breached or failed to perform any of its respective representations, warranties, covenants or other agreements in the merger agreement such that the related closing condition would not be satisfied (subject to Mandiant not being in material breach of the merger agreement at the time of such termination); or

•

prior to the adoption of the merger agreement by our stockholders: (1) Mandiant has received a superior proposal; (2) the Mandiant Board (or a committee thereof) has authorized Mandiant to enter into a definitive alternative acquisition agreement to consummate the acquisition transaction contemplated by that superior proposal and Mandiant and the counterparties thereto execute and deliver such definitive alternative acquisition agreement concurrently with or

TABLE OF CONTENTS

within the first business day occurring on or after Mandiant’s termination of the merger agreement; (3) prior to or concurrently with such termination, Mandiant pays to Parent the applicable termination fee; and (4) Mandiant has complied with its covenants under the merger agreement with respect to soliciting such superior proposal.

•

by Parent if:

•

subject to a 45-day cure period, Mandiant has breached or failed to perform any of its representations, warranties, covenants or other agreements in the merger agreement such that the related closing condition would not be satisfied (subject to Parent or Merger Sub not being in material breach of the merger agreement at the time of such termination);

•

the Mandiant Board (or a committee thereof) (1) changes its recommendation with respect to the merger; (2) Mandiant enters into an alternative acquisition agreement; or (3) Mandiant has committed a material and willful breach of its “no-shop” restrictions or covenants relating to its stockholder meeting to adopt the merger agreement and approve the merger; or

•

if an order arising under any of the antitrust and FDI laws, or any antitrust and FDI laws, has been issued, enacted, rendered, promulgated, enforced or deemed applicable by any governmental authority of competent jurisdiction that will expressly impose a remedial action in connection with the consummation of either the merger or the conversion of the convertible preferred stock and the imposition of such remedial action shall have become final and non-appealable, except Parent may not terminate the merger agreement pursuant to this provision if Parent’s action or failure to act constitutes a material breach of the merger agreement and has been the primary cause of, or primarily resulted in, the imposition of such remedial action or in such remedial action becoming final and non-appealable or failing to be removed.

Termination Fees and Remedies

The merger agreement contains certain termination rights for Mandiant and Parent. Upon valid termination of the merger agreement under specified circumstances, Mandiant will be required to pay Parent (or its designee) a termination fee of $197,000,000. Specifically, this termination fee will be payable by Mandiant to Parent if the merger agreement is terminated:

•

by Parent, if the Mandiant Board (or a committee thereof) changes its recommendation with respect to the merger, Mandiant enters into an alternative acquisition agreement or Mandiant has committed a material and willful breach of its “no-shop” restrictions or covenants relating to its stockholder meeting to adopt the merger agreement and approve the merger; or

•

by Mandiant, if, prior to receiving the requisite stockholder approval, the Mandiant Board (or a committee thereof) authorizes the acceptance of a superior proposal and Mandiant enters into a definitive alternative acquisition agreement for the transaction contemplated by such superior proposal.

The termination fee will also be payable in certain circumstances if:

•

the merger agreement is terminated (1) because the merger is not completed by the termination date; (2) because of a failure to obtain the required approval of our stockholders; or (3) subject to a 45-day cure period, because Mandiant breaches or fails to perform any of its representations, warranties or covenants in a manner that would cause the related closing conditions to not be satisfied;

•

prior to such termination (but after the date of the merger agreement) an acquisition proposal is publicly announced or publicly disclosed or delivered to the Mandiant Board and, in the case of a termination for a failure to obtain the requisite approval of Mandiant’s stockholders, is not withdrawn or otherwise abandoned at least one business day before such vote is taken; and

•

Mandiant subsequently consummates, or enters into a definitive agreement providing for, an acquisition transaction that is subsequently consummated (or is terminated but a subsequent acquisition transaction is subsequently consummated), in either case, within one year of such termination.

Upon termination of the merger agreement under other specified circumstances, Parent will be required to pay Mandiant a termination fee in the amount of (a) $328,000,000 if a termination notice is

TABLE OF CONTENTS

delivered on or prior to 11:59 p.m., Pacific time, on March 7, 2023, (b) $394,000,000 if a termination notice is delivered at any time after 11:59 p.m., Pacific time, on March 7, 2023 but on or prior to 11:59 p.m., Pacific time, on June 7, 2023; and (c) $460,000,000 if a termination notice is delivered at any time after 11:59 p.m., Pacific time, on June 7, 2023. Specifically, the termination fee will be payable by Parent to Mandiant if the merger agreement is terminated:

•

by Parent or Mandiant if the merger is not completed by the termination date and at such time (1) the closing conditions requiring (i) the receipt of certain antitrust and FDI clearances, (ii) the absence of any law, injunction or order preventing, materially restraining or materially impairing the merger or the conversion of the convertible preferred stock into common stock (if arising as a result of antitrust and FDI laws) and (iii) the absence of any order under any antitrust or FDI law and the absence of any antitrust or FDI law enacted imposing certain remedial actions in connection with the merger or the conversion of the convertible preferred stock into common stock, in each case, have not been satisfied or waived (if a waiver is permitted by law); (2) such non-satisfaction is not primarily caused by a material breach by Mandiant of the merger agreement; and (3) all other conditions to the obligations of Parent and Merger Sub to effect the merger under the merger agreement have been satisfied or waived (if a waiver is permitted by law); or

•

(1) by Parent or Mandiant if a Restraint (if arising as a result of antitrust or FDI laws); or (2) by Parent if an order under any antitrust or FDI law is in effect or any antitrust or FDI law has been enacted imposing certain remedial actions in connection with the merger or the conversion of the convertible preferred stock into common stock and at such time, in either case, has become final and non-appealable (and a material breach by Mandiant is not the primary cause of such law, injunction or order becoming final and non-appealable or failing to be removed or such remedial action being imposed) and all of the other conditions to the obligations of Parent and Merger Sub to effect the merger under the merger agreement have been satisfied or waived (if a waiver is permitted by law).

The merger agreement also provides that Mandiant, on the one hand, or Parent and Merger Sub, on the other hand, may specifically enforce the obligations under the merger agreement.

Neither Parent nor Mandiant is required to pay to the other its termination fee on more than one occasion.

Delisting and Deregistration of Our Common Stock

If the merger is completed, our common stock will no longer be traded on the Nasdaq and will be deregistered under the Securities Exchange Act of 1934 (which we refer to as the “Exchange Act”). We will no longer be required to file periodic reports, current reports and proxy and information statements with the Securities and Exchange Commission (which we refer to as the “SEC”) on account of our common stock.

Effect on Mandiant if the Merger is Not Completed

TABLE OF CONTENTS

QUESTIONS AND ANSWERS

The following questions and answers address some commonly asked questions regarding the merger, the merger agreement and the special meeting. These questions and answers may not address all questions that are important to you. We encourage you to carefully read the more detailed information contained elsewhere in this proxy statement, including the annexes to this proxy statement and the other documents to which we refer in this proxy statement. You may obtain the information incorporated by reference in this proxy statement without charge by following the instructions in the section of this proxy statement captioned “Where You Can Find More Information.”

Why am I receiving these materials?

On March 7, 2022, we announced that Mandiant entered into the merger agreement. Under the merger agreement, Parent will acquire Mandiant for $23.00 in cash per share of our common stock. In order to complete the merger, our stockholders representing a majority of all issued and outstanding common stock and convertible preferred stock, voting as a single class on an as-converted basis, must vote to adopt the merger agreement at the special meeting. This approval is a condition to the consummation of the merger. See the section of this proxy statement captioned “The Merger Agreement — Conditions to the Closing of the Merger.” The Mandiant Board is furnishing this proxy statement and form of proxy card to the holders of shares of our common stock and convertible preferred stock in connection with the solicitation of proxies of our stockholders to be voted at the special meeting.

This proxy statement, which you should read carefully, contains important information about the merger, the merger agreement, the special meeting and the matters to be voted on at the special meeting. The enclosed materials allow you to submit a proxy to vote your shares of our common stock without attending the special meeting and to ensure that your shares of our common stock are represented and voted at the special meeting.

Your vote is very important. Even if you plan to attend the special meeting, we encourage you to submit a proxy as soon as possible.

What is the proposed merger and what effects will it have on Mandiant?

The proposed merger is the acquisition of Mandiant by Parent. If the proposal to adopt the merger agreement is approved by our stockholders and the other closing conditions under the merger agreement are satisfied or waived, Merger Sub will merge with and into Mandiant, with Mandiant continuing as the surviving corporation. As a result of the merger, Mandiant will become a wholly owned subsidiary of Parent, and our common stock will no longer be publicly traded and will be delisted from the Nasdaq. In addition, our common stock will be deregistered under the Exchange Act, and we will no longer file periodic reports with the SEC.

What will I receive if the merger is completed?

Upon completion of the merger, you will be entitled to receive $23.00 in cash, without interest and less any applicable withholding taxes, for each share of our common stock that you own, unless you have properly exercised, and not validly withdrawn or subsequently lost, your appraisal rights under the DGCL, and certain other conditions under the DGCL are satisfied. For example, if you own 100 shares of our common stock, you will receive $2,300.00 in cash in exchange for your shares of our common stock, without interest and less any applicable withholding taxes.

How does the per share price compare to the market price of Mandiant’s common stock?

This amount constitutes (1) a premium of approximately 53 percent to the closing price of our common stock on February 7, 2022, which was the last full trading day before media reports that Mandiant was pursuing a sale; and (2) a premium of approximately 57 percent to Mandiant’s unaffected 10-day volume weighted average price as of February 7, 2022.

TABLE OF CONTENTS

What will happen to Mandiant equity-based awards and Mandiant options?

Generally speaking, Mandiant equity-based awards and Mandiant options will be treated as follows:

•

Each vested Mandiant restricted stock unit will accelerate vesting in full (to the extent not already vested) and be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such vested Mandiant restricted stock unit; and (2) the total number of shares of our common stock then-subject to such vested Mandiant restricted stock unit. This amount (less any required withholding and other taxes) will be paid to the applicable holder promptly following the effective time of the merger.

•

Each unvested Mandiant restricted stock unit will be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such unvested Mandiant restricted stock unit; and (2) the total number of shares of our common stock then-subject to such unvested Mandiant restricted stock unit. Such cash amount will (1) vest and become payable (less any required withholding and other taxes) in accordance with the vesting schedule applicable to the corresponding unvested Mandiant restricted stock unit immediately prior to the effective time of the merger, subject to such holder’s continued service with Parent and its affiliates through the applicable vesting dates; and (2) be subject to the terms and conditions of the unvested payment plan.

•

All other Mandiant restricted stock units not described above that are outstanding immediately prior to the effective time of the merger will be canceled for no consideration.

•

Each completed Mandiant PSU will be canceled and converted into a right to receive an amount in cash, without interest, equal to the completed Mandiant PSU consideration, with such completed Mandiant PSU consideration vesting in accordance with the service-based vesting schedule applicable to such completed Mandiant PSU immediately prior to the effective time of the merger and subject to the terms of the unvested payment plan.

•

At the effective time of the merger, each uncompleted Mandiant PSU will be canceled and converted into a right to receive, an amount in cash, without interest, equal to the uncompleted Mandiant PSU consideration with such uncompleted Mandiant PSU consideration vesting in accordance with the service-based vesting schedule applicable to such uncompleted Mandiant PSU immediately prior to the effective time of the merger and subject to the terms of the unvested payment plan.

•

Each Mandiant option that is outstanding and unexercised as of immediately prior to the effective time of the merger will accelerate vesting in full and be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess, if any, of the per share price over the exercise price per share of such Mandiant option, and (2) the number of shares of our common stock then issuable upon exercise in full of such Mandiant option. This amount (less any required withholding and other taxes) will be paid to the applicable holder promptly following the effective time of the merger.

•

What will happen to the ESPP?

Generally speaking, the ESPP will be treated as follows:

•

No further offering period or purchase period will commence pursuant to the ESPP following the closing date of the merger. The ESPP will be terminated immediately prior to and effective as of the effective time of the merger (subject to consummation of the merger).

•

Any offering period or purchase period under the ESPP that otherwise would be in progress as of the effective time of the merger will be terminated no later than ten (10) business days prior to the effective time of the merger.

TABLE OF CONTENTS

•

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

You are being asked to vote on the following proposals:

•

to adopt the merger agreement pursuant to which Merger Sub will merge with and into Mandiant and Mandiant will become a wholly owned subsidiary of Parent;

•

to approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger; and

•

to approve the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

When and where is the special meeting?

The special meeting will take place on [•], 2022, at [•] [a.m./p.m.], Pacific time. The special meeting will be held virtually and there is no physical meeting location.

How do I attend the special meeting?

If you were a holder of record of Mandiant stock at the close of business on [•], you can attend the virtual special meeting by visiting [•] and entering both the 11-digit control number previously provided to you in your proxy materials and the meeting password. The password for the meeting is [•]. If you are a stockholder of record and you have misplaced your 11-digit control number, please call AST at (800) 937-5449.

If your shares are held in “street name” through a bank, broker or other nominee), you must register in advance in order to attend the special meeting. To register, you must obtain a “legal proxy” from the bank, broker or other nominee that is the record holder of your shares. Then you must submit the legal proxy, along with your name and email address, to receive an 11-digit control number that may be used to access the virtual special meeting website provided above. Any control number that was previously provided with your proxy materials, likely a 16-digit number, will not provide access to the virtual special meeting website. Requests for registration and submission of legal proxies should be labeled as “Legal Proxy” and must be received by American Stock Transfer & Trust Company LLC no later than 5:00 p.m. Eastern time, on [•]. Submit your registration request and legal proxy by: (1) email to proxy@astfinancial.com; (2) facsimile to 718-765-8730, or (3) mail to American Stock Transfer & Trust Company, LLC, Attn: Proxy Tabulation Department, 6201 15th Avenue, Brooklyn, NY 11219. Obtaining a legal proxy may take several days and you are advised to register as far in advance as possible. Once you have obtained your 11-digit control number from AST, please follow the steps set forth in the prior paragraph for stockholders of record to attend the special meeting.

The virtual special meeting website will be active one hour prior to the start of the special meeting and stockholders are encouraged to log in to the virtual special meeting website early. Only stockholders who have an 11-digit control number may attend and vote during the special meeting. Stockholders experiencing technical difficulties accessing the special meeting may visit https://go.lumiglobal.com/faq for assistance.

Who is entitled to vote at the special meeting?

All of our stockholders as of the close of business on [•], 2022, which is the record date for the special meeting, are entitled to vote their shares of our common stock at the special meeting. As of the close of business on the record date, there were [•] shares of our common stock outstanding and entitled to vote at the special meeting. Each share of our common stock outstanding as of the record date is entitled

TABLE OF CONTENTS

to one vote per share on each matter properly brought before the special meeting. Each share of our convertible preferred stock outstanding as of the record date is entitled to one vote per share of common stock, on an as-converted-into-common-stock basis, on each matter properly brought before the special meeting.

What vote is required to approve the proposal to adopt the merger agreement?

The affirmative vote of the holders of a majority of the shares of our common stock and convertible preferred stock, voting as a single class on an as-converted basis, outstanding as of the record date is required to adopt the merger agreement.

The failure of any stockholder of record to (1) submit a signed proxy card; (2) grant a proxy over the internet or by telephone; or (3) vote at the special meeting will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. If you hold your shares in “street name,” the failure to instruct your bank, broker or other nominee how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. Abstentions will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement.

What vote is required to approve (1) the proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger; and (2) the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting?

Approval of the proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger requires the affirmative vote of a majority of the voting power of the shares of our common stock present in person or represented by proxy at the special meeting and entitled to vote on the proposal.

Approval of the proposal to adjourn the special meeting to a later date or dates to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting requires the affirmative vote of a majority of the voting power of the shares of our common stock present in person or represented by proxy at the special meeting and entitled to vote on the proposal.

The failure of any stockholder of record to (1) submit a signed proxy card; (2) grant a proxy over the internet or by telephone; or (3) vote at the special meeting will not have any effect on the proposal to approve, on a nonbinding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger, or the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting, except to the extent that such failure affects obtaining a quorum at the meeting. If you hold your shares in “street name,” the failure to instruct your bank, broker or other nominee how to vote your shares will not have any effect on these proposals, except to the extent that such failure affects obtaining a quorum at the meeting. In all cases, abstentions will have the same effect as a vote “AGAINST” these proposals.

What do I need to do now?

We encourage you to read this proxy statement, the annexes to this proxy statement and the documents that we refer to in this proxy statement carefully and consider how the merger affects you. Then, even if you expect to attend the special meeting, please sign, date and return, as promptly as possible, the enclosed proxy card (a prepaid reply envelope is provided for your convenience), or grant your proxy electronically over the internet or by telephone (using the instructions found on the proxy card), so that your shares can be voted at the special meeting. If you hold your shares in “street name,” please refer to the voting instruction form provided by your bank, broker or other nominee for information on how to vote your shares. Please do not send your stock certificates with your proxy card.

How does the Mandiant Board recommend that I vote?

TABLE OF CONTENTS

in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

What happens if the merger is not completed?

If the merger agreement is not adopted by our stockholders or if the merger is not completed for any other reason, our stockholders will not receive any payment for their shares of our common stock. Instead: (1) Mandiant will remain an independent public company; (2) our common stock will continue to be listed and traded on the Nasdaq and registered under the Exchange Act; and (3) we will continue to file periodic reports with the SEC.

In specified circumstances in which the merger agreement is terminated, Mandiant has agreed to pay Parent (or its designee) a termination fee. In other specified circumstances in which the merger agreement is terminated, Parent has agreed to pay Mandiant a termination fee.

For more information, see the section of this proxy statement captioned “The Merger Agreement — Termination Fees and Remedies.”

What is the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger?

The compensation that will or may become payable to our named executive officers in connection with the merger is certain compensation that is tied to or based on the merger and payable to certain of Mandiant’s named executive officers pursuant to underlying employee benefit plans and arrangements that are contractual in nature. Compensation that will or may become payable by Parent or its affiliates (including, following the consummation of the merger, the surviving corporation) to our named executive officers pursuant to arrangements entered into between Parent and our named executive officers in connection with or following the merger is not subject to this advisory vote. For further information, see the section of this proxy statement captioned “Proposal 2: Approval, on a Non-Binding, Advisory Basis, of Certain Merger-Related Executive Compensation.”

Why am I being asked to cast a vote to approve the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger?

Mandiant is required to seek approval, on a non-binding, advisory basis, of compensation that will or may become payable to our named executive officers in connection with the merger. Approval of the compensation that will or may become payable to our named executive officers in connection with the merger is not required to consummate the merger.

What will happen if Mandiant’s stockholders do not approve the compensation that will or may become payable to Mandiant’s named executive officers in connection with the merger?

Approval of the compensation that will or may become payable to our named executive officers in connection with the merger is not a condition to consummation of the merger. This is an advisory vote and will not be binding on Mandiant or Parent. The underlying plans and arrangements providing for such compensation are contractual in nature and are not, by their terms, subject to stockholder approval.

Accordingly, if the merger agreement is adopted by our stockholders and the merger is consummated, the compensation that will or may become payable to our named executive officers in connection with the merger will or may be paid to Mandiant’s named executive officers even if our stockholders do not approve such compensation.

What is the difference between holding shares as a stockholder of record and as a beneficial owner?

If your shares are registered directly in your name with our transfer agent, AST, you are considered, with respect to those shares, to be the “stockholder of record.” If you are a stockholder of record, this proxy statement and your proxy card have been sent directly to you by or on behalf of Mandiant. As

TABLE OF CONTENTS

a stockholder of record, you may attend the special meeting and vote your shares at the special meeting using the control number on the enclosed proxy card.

If your shares are held through a bank, broker or other nominee, you are considered the “beneficial owner” of shares of our common stock held in “street name.” If you are a beneficial owner of shares of our common stock held in “street name,” this proxy statement has been forwarded to you by your bank, broker or other nominee who is considered, with respect to those shares, to be the stockholder of record. As the beneficial owner, you have the right to direct your bank, broker or other nominee how to vote your shares by following their instructions for voting. You are also invited to attend the special meeting. However, because you are not the stockholder of record, you may not vote your shares at the special meeting unless you provide a “legal proxy” from your bank, broker or other nominee giving you the right to vote your shares at the special meeting.

If my broker holds my shares in “street name,” will my broker vote my shares for me?

No. Your bank, broker or other nominee is permitted to vote your shares on any proposal currently scheduled to be considered at the special meeting only if you instruct your bank, broker or other nominee how to vote. You should follow the procedures provided by your bank, broker or other nominee to vote your shares. Without instruction, your shares will not be counted for the purpose of obtaining a quorum or voted on the proposals, which will have the same effect as if you voted “AGAINST” adoption of the merger agreement, but will have no effect on the proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger or the adjournment proposal, except to the extent affecting the obtaining of a quorum at the meeting.

How may I vote?

If you are a stockholder of record (that is, if your shares of our common stock are registered in your name with AST, our transfer agent), there are four ways to vote:

•

by signing, dating and returning the enclosed proxy card (a prepaid reply envelope is provided for your convenience);

•

by visiting the internet address on your proxy card;

•

by calling the toll-free (within the U.S. or Canada) phone number on your proxy card; or

•

by attending the special meeting and voting at the special meeting using the control number on the enclosed proxy card.

The control number located on your proxy card is designed to verify your identity and allow you to vote your shares of our common stock and to confirm that your voting instructions have been properly recorded when voting electronically over the internet or by telephone. Although there is no charge for voting your shares, if you vote electronically over the internet or by telephone, you may incur costs such as internet access and telephone charges for which you will be responsible.

Even if you plan to attend the special meeting, you are strongly encouraged to vote your shares of our common stock by proxy. If you are a stockholder of record or if you obtain a “legal proxy” to vote shares that you beneficially own, you may still vote your shares of our common stock at the special meeting even if you have previously voted by proxy. If you attend the special meeting and vote at the special meeting, your vote will revoke any previously submitted proxy.

If your shares are held in “street name” through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting instruction form provided by your bank, broker or other nominee, or, if such a service is provided by your bank, broker or other nominee, electronically over the internet or by telephone. To vote over the internet or by telephone through your bank, broker or other nominee, you should follow the instructions on the voting instruction form provided by your bank, broker or nominee. However, because you are not the stockholder of record, you may not vote your shares at the special meeting unless you provide a “legal proxy” from your bank, broker or other nominee giving you the right to vote your shares at the special meeting.

TABLE OF CONTENTS

Why did Mandiant choose to hold a virtual special meeting?

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

What is a proxy?

A proxy is your legal designation of another person, referred to as a “proxy,” to vote your shares of our common stock. The written document describing the matters to be considered and voted on at the special meeting is called a “proxy statement.” The document used to designate a proxy to vote your shares of our common stock is called a “proxy card.” You may follow the instructions on the proxy card to designate a proxy by telephone or by the Internet in the same manner as if you had signed, dated and returned a proxy card. [•] and [•], each with full powers of substitution and resubstitution, are the proxy holders for the special meeting.

May I change my vote after I have mailed my signed and dated proxy card?

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

•

signing another proxy card with a later date and returning it to us prior to the special meeting;

•

submitting a new proxy electronically over the internet or by telephone after the date of the earlier submitted proxy;

•

delivering a written notice of revocation to our Corporate Secretary; or

•

attending the special meeting and voting at the special meeting using the control number on the enclosed proxy card.

If a stockholder gives a proxy, how are the shares voted?

Regardless of the method you choose to grant your proxy, the individuals named on the enclosed proxy card will vote your shares in the way that you direct.

If you sign and date your proxy card but do not mark the boxes showing how your shares should be voted on a matter, the shares represented by your properly signed proxy will be voted as recommended by the Mandiant Board with respect to each proposal. This means that they will be voted: (1) “FOR” the adoption of the merger agreement; (2) “FOR” the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Should I send in my stock certificates now?

No. After the merger is completed, any holders of physical stock certificates will receive a letter of transmittal containing instructions for how to send your stock certificates to the payment agent in order to receive the appropriate cash payment for the shares of our common stock represented by your stock certificates. Unless you are seeking appraisal, you should use the letter of transmittal to exchange your stock certificates for the cash payment to which you are entitled. Please do not send your stock certificates with your proxy card. If you hold your shares of our common stock in book-entry form, you will not receive a letter of transmittal. Instead the payment agent will pay you the appropriate portion of the merger consideration upon receipt of a customary “agent’s message” and any other items specified by the payment agent.

TABLE OF CONTENTS

What happens if I sell or transfer my shares of common stock after the record date but before the special meeting?

The record date for the special meeting is earlier than the date of the special meeting and the expected effective date of the merger. If you sell or transfer your shares of our common stock after the record date but before the special meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you sell or transfer your shares and each of you notifies Mandiant in writing of such special arrangements, you will transfer the right to receive the per share price with respect to such shares, if the merger is completed, to the person to whom you sell or transfer your shares, but you will retain your right to vote those shares at the special meeting. Even if you sell or transfer your shares of our common stock after the record date, we encourage you to sign, date and return the enclosed proxy card (a prepaid reply envelope is provided for your convenience) or grant your proxy electronically over the internet or by telephone (using the instructions found on the proxy card).

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

Please sign, date and return (or grant your proxy electronically over the internet or by telephone for) each proxy card and voting instruction form that you receive to ensure that all of your shares are voted.

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

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

If available, Mandiant may announce preliminary voting results at the conclusion of the special meeting. Mandiant intends to publish final voting results in a Current Report on Form 8-K to be filed with the SEC following the special meeting. All reports that Mandiant files with the SEC are publicly available when filed. See the section of this proxy statement captioned “Where You Can Find More Information.”

Will I be subject to U.S. federal income tax upon the exchange of common stock for cash pursuant to the merger?

If you are a U.S. Holder, the exchange of our common stock for cash pursuant to the merger will be a taxable transaction for U.S. federal income tax purposes, which generally will require a U.S. Holder to recognize gain or loss for U.S. federal income tax purposes in an amount equal to the difference, if any, between the amount of cash received by such U.S. Holder in the merger and such U.S. Holder’s adjusted tax basis in the shares of our common stock surrendered in the merger.

Because particular circumstances may differ, we recommend that you consult your own tax advisor to determine the U.S. federal income tax consequences relating to the merger in light of your own particular circumstances and any consequences arising under U.S. federal non-income tax laws or the laws of any state, local or foreign taxing jurisdiction. This discussion is provided for general information only and does not constitute legal advice to any holder. A more complete description of material U.S. federal income tax consequences of the merger is provided in the section of this proxy statement captioned “The Merger — Material U.S. Federal Income Tax Consequences of the Merger.”

TABLE OF CONTENTS

When do you expect the merger to be completed?

We currently expect to complete the merger in 2022. However, the exact timing of completion of the merger, if at all, cannot be predicted because the merger is subject to the closing conditions specified in the merger agreement, many of which are outside of our control.

What governmental and regulatory approvals are required?

Under the terms of the merger agreement, the merger cannot be completed until the waiting period applicable to the merger under the HSR Act has expired or been terminated.

The initial waiting period under the HSR Act is set to expire at 11:59 p.m., Eastern time, on April 20, 2022.

The merger is subject to clearances, consents, approvals and the waiting periods applicable to the merger under certain foreign antitrust laws and FDI laws. Antitrust and FDI approvals of the merger are required in various jurisdictions throughout Europe, the Middle East and Asia.

Am I entitled to appraisal rights under the DGCL?

If the merger is consummated, our stockholders who (1) do not vote in favor of the adoption of the merger agreement; (2) continuously hold their shares of our common stock through the effective time of the merger; (3) properly perfect appraisal of their shares; (4) meet certain other conditions and statutory requirements as described in this proxy statement; and (5) do not withdraw their demands or otherwise lose their rights to appraisal, will be entitled to seek appraisal of their shares in connection with the merger under Section 262 of the DGCL. This means that such stockholders will be entitled to have their shares appraised by the Delaware Court of Chancery and to receive payment in cash for the “fair value” of their shares, exclusive of any elements of value arising from the accomplishment or expectation of the merger, together with (unless the Delaware Court of Chancery in its discretion determines otherwise for good cause shown) interest on the amount determined by the Delaware Court of Chancery to be the fair value from the effective date of the merger through the date of payment of the judgment at a rate of five percent over the Federal Reserve discount rate (including any surcharge) as established from time to time during the period between the effective date of the merger and the date of payment of the judgment, compounded quarterly (except that, if at any time before the entry of judgment in the proceeding, the surviving corporation makes a voluntary cash payment to each stockholder seeking appraisal, interest will accrue thereafter only upon the sum of (1) the difference, if any, between the amount so paid and the fair value of the shares as determined by the Delaware Court of Chancery; and (2) interest theretofore accrued, unless paid at that time). The surviving corporation is under no obligation to make such voluntary cash payment prior to such entry of judgment. Stockholders who wish to seek appraisal of their shares are encouraged to seek the advice of legal counsel with respect to the exercise of appraisal rights due to the complexity of the appraisal process. The DGCL requirements for exercising appraisal rights are described in additional detail in this proxy statement, which description is qualified in its entirety by Section 262 of the DGCL regarding appraisal rights, attached as Annex B to this proxy statement.

Do any of Mandiant’s directors or officers have interests in the merger that may differ from those of Mandiant stockholders generally?

Yes. In considering the recommendation of the Mandiant Board with respect to the proposal to adopt the merger agreement, you should be aware that our directors and executive officers may have interests in the merger that are different from, or in addition to, the interests of our stockholders generally. In: (1) evaluating and negotiating the merger agreement; (2) approving the merger agreement and the merger; and (3) unanimously recommending that the merger agreement be adopted by our stockholders, the Mandiant Board was aware of and considered these interests to the extent that they existed at the time, among other matters. For more information, see the section of this proxy statement captioned “The Merger — Interests of Mandiant’s Directors and Executive Officers in the Merger.”

TABLE OF CONTENTS

FORWARD-LOOKING STATEMENTS

This proxy statement, the documents to which we refer you in this proxy statement and information included in oral statements or other written statements made or to be made by us or on our behalf contain “forward-looking statements” that do not directly or exclusively relate to historical facts, including, without limitation, statements relating to the completion of the merger. You can typically identify forward-looking statements by the use of forward-looking words, such as “may,” “should,” “could,” “project,” “believe,” “anticipate,” “expect,” “estimate,” “continue,” “potential,” “plan,” “forecast” and other words of similar import. Our stockholders are cautioned that any forward-looking statements are not guarantees of future performance and may involve significant risks and uncertainties, and that actual results may vary materially from those in the forward-looking statements. These risks and uncertainties include, but are not limited to, the risks detailed in our filings with the SEC, including in our most recent filings on Forms 10-K and 10-Q, factors and matters described or incorporated by reference in this proxy statement, and the following factors:

•

the inability to complete the merger due to the failure of our stockholders to adopt the merger agreement or the failure to satisfy the other conditions to the completion of the merger, including that a governmental entity may prohibit, delay or refuse to grant a necessary regulatory approval;

•

the risk that the merger agreement may be terminated in circumstances that require us to pay a termination fee;

•

the outcome of any legal proceedings that may be instituted against us and others related to the merger agreement;

•

risks that the merger affects our current operations or our ability to retain or recruit employees;

•

the fact that receipt of the all-cash per share price will be taxable to our stockholders that are treated as U.S. Holders for U.S. federal income tax purposes;

•

the fact that, if the merger is completed, our stockholders will forgo the opportunity to realize the potential long-term value of the successful execution of Mandiant’s current strategy as an independent company;

•

the possibility that Mandiant could, at a later date, engage in unspecified transactions, including restructuring efforts, special dividends or the sale of some or all of Mandiant’s assets to one or more as yet unknown purchasers, that could conceivably produce a higher aggregate value than that available to our stockholders in the merger;

•

the fact that under the terms of the merger agreement, Mandiant is restrained from soliciting other acquisition proposals during the pendency of the merger;

•

the effect of the announcement or pendency of the merger on our business relationships, customers, operating results and business generally, including risks related to the diversion of the attention of Mandiant management or employees during the pendency of the merger;

•

the amount of the costs, fees, expenses and charges related to the merger agreement or the merger;

•

the risk that the proposed merger will not be consummated in a timely manner, exceeding the expected costs of the merger;

•

the risk that our stock price may fluctuate during the pendency of the merger and may decline significantly if the merger is not completed;

•

risks related to obtaining the requisite stockholder approval to the merger; and

•

the risk that our financial results differ from those set forth in the projections described in this proxy statement.

Consequently, all of the forward-looking statements that we make in this proxy statement are qualified by the information contained or incorporated by reference in this proxy statement, including: (1) the information contained under this caption; and (2) information in our most recent filings on Form 10-K and Form 10-Q, including the information contained under the caption “Risk Factors,” and information in

TABLE OF CONTENTS

THE SPECIAL MEETING

Date, Time and Place

We will hold the special meeting on [•], 2022, at [•] [a.m./p.m.], Pacific time. You may attend the special meeting via a live interactive webcast on the Internet at [•]. You will be able to listen to the special meeting live and vote online. We elected to use a virtual meeting given the current public health implications of COVID-19 and our desire to promote the health and welfare of our stockholders, as well as our positive experiences with virtual meetings.

Purpose of the Special Meeting

At the special meeting, we will ask stockholders to vote on proposals to (1) adopt the merger agreement; (2) approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) adjourn the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Attending the Special Meeting

The special meeting will begin at [•] [a.m./p.m.], Pacific time. Online check-in will begin a few minutes prior to the special meeting. We encourage you to access the meeting prior to the start time.

As the special meeting is virtual, there will be no physical meeting location. To attend the special meeting, log in at [•]. You will need the control number found on your proxy card or voting instruction form in order to participate in the special meeting (including voting your shares). If you encounter technical difficulties accessing the special meeting or during the special meeting, a support line will be available on the login page of the special meeting website.

Once online access to the special meeting is open, stockholders may submit questions, if any, through the special meeting website. You will need the control number found on your proxy card or voting instruction form in order to submit questions. Questions pertinent to meeting matters will be answered during the meeting, subject to time constraints.

Record Date; Shares Entitled to Vote; Quorum

Only our stockholders as of the close of business on the record date are entitled to notice of, and to vote at, the special meeting. A list of stockholders of record entitled to vote at the special meeting will be available at our corporate offices located at 11951 Freedom Drive, 6th Floor, Reston, Virginia 20190, during regular business hours for a period of no less than 10 days before the special meeting and at the place of the special meeting during the meeting.

As of the record date, there were [•] shares of our common stock outstanding and entitled to vote at the special meeting. As of the record date, there were 400,000 shares of our convertible preferred stock issued and outstanding, which are convertible into, in the aggregate, at the option of the holder [•] shares of our common stock, and entitled to vote on an as-converted-into-common-stock basis at the special meeting. Each share of our common stock outstanding as of the close of business on the record date is entitled to one vote per share on each matter submitted for a vote at the special meeting.

The holders of a majority of the stock issued and outstanding and entitled to vote, present in person or represented by proxy, shall constitute a quorum.

Vote Required; Abstentions and Broker Non-Votes

Approval of the proposal to adopt the merger agreement requires the affirmative vote of the holders of a majority of the issued shares of our common stock and convertible preferred stock, voting as a single class on an as-converted basis, outstanding as of the record date. Adoption of the merger agreement by our stockholders is a condition to the closing of the merger.

TABLE OF CONTENTS

Approval, on a non-binding, advisory basis, of the compensation that will or may become payable to our named executive officers in connection with the merger requires the affirmative vote of a majority of the voting power of the shares of our common stock and convertible preferred stock, voting as a single class on an as-converted basis, present in person or represented by proxy at the special meeting and entitled to vote on the proposal.

Approval of the proposal to adjourn the special meeting to a later date or dates to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting requires the affirmative vote of a majority of the shares of our common stock and convertible preferred stock, voting as a single class on an as-converted basis, present in person or represented by proxy at the special meeting and entitled to vote on the proposal.

If a stockholder abstains from voting, that abstention will have the same effect as if the stockholder voted: (1) “AGAINST” the proposal to adopt the merger agreement; (2) “AGAINST” the proposal to approve, on a nonbinding, advisory basis, compensation that will or may become payable to our named executive officers in connection with the merger; and (3) “AGAINST” any proposal to adjourn the special meeting to a later date to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting. Abstentions will be counted as present for purposes of determining whether a quorum exists.

A “broker non-vote” generally occurs when a bank, broker or other nominee holding shares on your behalf does not vote on a proposal because the bank, broker or other nominee has not received your voting instructions and lacks discretionary power to vote your shares. We do not expect any “broker non-votes” at the special meeting, but if there are any, they will be counted for the purpose of determining whether a quorum is present. If there are broker non-votes, each broker non-vote will count as a vote “AGAINST” the proposal to adopt the merger agreement, but will have no effect on: (1) the proposal to approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger; or (2) the proposal to adjourn the special meeting to a later date to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Shares Held by Mandiant’s Directors and Executive Officers

As of the record date, our directors and executive officers beneficially owned and were entitled to vote, in the aggregate, [•] shares of our common stock, representing approximately [•] percent of the shares of our common stock outstanding as of the record date. Our directors and executive officers have informed us that they intend to vote all of their shares of our common stock: (1) “FOR” the adoption of the merger agreement; (2) “FOR” the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting. Mr. Mandia, in his capacity as a stockholder of Mandiant, has entered into a voting agreement and against any competing transaction with Parent and Mandiant, which obligates Mr. Mandia to vote certain of his shares of our common stock in favor of the adoption of the merger agreement. For more information, please see the section of this proxy statement captioned “The Merger — The Voting Agreements.”

Voting of Proxies

If your shares are registered in your name with our transfer agent, AST, you may vote your shares by returning a signed and dated proxy card (a prepaid reply envelope is provided for your convenience), or you may vote at the special meeting using the control number located on the enclosed proxy card. Additionally, you may grant a proxy electronically over the internet or by telephone by following the instructions on your proxy card. You must have the enclosed proxy card available, and follow the instructions on the proxy card, in order to grant a proxy electronically over the internet or by telephone. Based on your proxy cards or internet and telephone proxy, the proxy holders will vote your shares according to your direction.

If you attend the special meeting and wish to vote at the special meeting, you will need the control number located on the enclosed proxy card. Beneficial owners of shares held in “street name” must also provide a

TABLE OF CONTENTS

“legal proxy” from their bank or broker in order to vote at the special meeting. You are encouraged to vote by proxy even if you plan to attend the special meeting. If you attend the special meeting and vote at the special meeting, your vote will revoke any previously submitted proxy.

All shares represented by properly signed and dated proxies received will, if received before the special meeting, be voted at the special meeting in accordance with the instructions of the stockholder. Properly signed and dated proxies that do not contain voting instructions will be voted: (1) “FOR” adoption of the merger agreement; (2) “FOR” the compensation that will or may become payable to our named executive officers in connection with the merger; and (3) “FOR” the adjournment of the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

If your shares are held in “street name” through a bank, broker or other nominee, you may vote through your bank, broker or other nominee by completing and returning the voting instruction form provided by your bank, broker or other nominee. You may also attend the special meeting and vote at the special meeting if you have a “legal proxy” from your bank, broker or other nominee giving you the right to vote your shares at the special meeting. If available from your bank, broker or other nominee, you may vote over the internet or telephone through your bank, broker or other nominee by following the instructions on the voting instruction form provided by your bank, broker or other nominee. If you do not (1) return your bank’s, broker’s or other nominee’s voting instruction form; (2) vote over the internet or by telephone through your bank, broker or other nominee; or (3) attend the special meeting and vote at the special meeting with a “legal proxy” from your bank, broker or other nominee, it will have the same effect as if you voted “AGAINST” the proposal to adopt the merger agreement. It will not, however, have any effect on the proposals (1) to approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger; or (2) to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the merger agreement at the time of the special meeting.

Revocability of Proxies

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

•

signing another proxy card with a later date and returning it to us prior to the special meeting;

•

submitting a new proxy electronically over the internet or by telephone after the date of the earlier submitted proxy;

•

delivering a written notice of revocation to our Corporate Secretary; or

•

attending the special meeting and voting at the special meeting using the control number on the enclosed proxy card.

If you have submitted a proxy, your attendance at the special meeting, in the absence of voting at the special meeting or submitting an additional proxy or revocation, will not have the effect of revoking your prior proxy.

If you hold your shares of our common stock in “street name” through a bank, broker or other nominee, you should contact your bank, broker or other nominee for instructions regarding how to change your vote. You may also vote at the special meeting if you obtain a “legal proxy” from your bank, broker or other nominee giving you the right to vote your shares at the special meeting.

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

The Mandiant Board’s Recommendation

TABLE OF CONTENTS

unanimously: (1) determined that the merger agreement, the merger and the other transactions contemplated by the merger agreement are fair to, advisable and in the best interests of Mandiant and its stockholders; and (2) adopted and approved the merger agreement, the merger and the other transactions contemplated by the merger agreement.

Adjournment

In addition to the proposals to (1) adopt the merger agreement and (2) approve, on a non-binding, advisory basis, the compensation that will or may become payable to our named executive officers in connection with the merger, our stockholders are also being asked to approve a proposal to adjourn the special meeting to a later date or dates, if necessary or appropriate, to solicit additional votes or proxies in favor of the proposal to adopt the merger agreement if there are insufficient votes at the time of the special meeting to approve the merger agreement. If a quorum is not present, the chairperson of the special meeting or if the chairperson does not act, the stockholders entitled to vote at the special meeting, present in person or represented by proxy, may adjourn the special meeting, from time to time, without notice other than announcement at the meeting, until a quorum is present or represented. In addition, the special meeting could be postponed before it commences, subject to the terms of the merger agreement. If the special meeting is adjourned or postponed, our stockholders who have already submitted their proxies will be able to revoke them at any time before they are voted at the special meeting.

Solicitation of Proxies

The expense of soliciting proxies will be borne by Mandiant. We have retained MacKenzie Partners, Inc., a professional proxy solicitation firm, to assist in the solicitation of proxies, and provide related advice and informational support during the solicitation process, for a fee of up to $17,500, plus reasonable out-of-pocket expenses. We will indemnify this firm against losses arising out of its provisions of these services on our behalf. In addition, we may reimburse banks, brokers and other nominees representing beneficial owners of shares of our common stock for their expenses in forwarding soliciting materials to such beneficial owners. Proxies may also be solicited by our directors, officers and employees, personally or by telephone, email, fax or over the internet. No additional compensation will be paid for such services.

Anticipated Date of Completion of the Merger

Appraisal Rights

If the merger is consummated, our stockholders who (1) do not vote in favor of the adoption of the merger agreement nor consent thereto in writing; (2) continuously hold their shares through the effective time of the merger; (3) properly perfect appraisal of their shares; (4) meet certain other conditions and statutory requirements described in this proxy statement; and (5) do not withdraw their demands or otherwise lose their rights to appraisal will be entitled to seek appraisal of their shares in connection with the merger under Section 262 of the DGCL. This means that such stockholders will be entitled to seek appraisal of their shares by the Delaware Court of Chancery and to receive payment in cash for the “fair value” of their shares of our common stock, exclusive of any elements of value arising from the accomplishment or expectation of the merger, together with (unless the Delaware Court of Chancery in its discretion determines otherwise for good cause shown) interest on the amount determined by the Delaware Court of Chancery to be the fair value from the effective date of the merger through the date of payment of the judgment at a rate of five percent over the Federal Reserve discount rate (including any surcharge) as established from time to time during the period between the effective date of the merger and the date of payment of the judgment,

TABLE OF CONTENTS

compounded quarterly (except that, if at any time before the entry of judgment in the proceeding, the surviving corporation makes a voluntary cash payment to stockholders seeking appraisal, interest will accrue thereafter only upon the sum of (1) the difference, if any, between the amount so paid and the fair value of the shares as determined by the Delaware Court of Chancery; and (2) interest theretofore accrued, unless paid at that time). The surviving corporation is under no obligation to make such voluntary cash payment prior to such entry of judgment. Due to the complexity of the appraisal process, stockholders who wish to seek appraisal of their shares are encouraged to seek the advice of legal counsel with respect to the exercise of appraisal rights.

Only a stockholder of record may submit a demand for appraisal. To exercise appraisal rights, the stockholder of record must (1) submit a written demand for appraisal to Mandiant before the vote is taken on the proposal to adopt the merger agreement; (2) not vote, in person or by proxy, in favor of the proposal to adopt the merger agreement; (3) continue to hold the subject shares of our common stock of record through the effective time of the merger; and (4) strictly comply with all other procedures for exercising appraisal rights under the DGCL. The failure to follow exactly the procedures specified under the DGCL may result in the loss of appraisal rights. In addition, the Delaware Court of Chancery will dismiss appraisal proceedings in respect of Mandiant unless certain conditions are satisfied by the stockholders seeking appraisal. The requirements under Section 262 of the DGCL for exercising appraisal rights are described in further detail in this proxy statement, which description is qualified in its entirety by Section 262 of the DGCL, the relevant section of the DGCL regarding appraisal rights, a copy of which is attached as Annex B to this proxy statement. If you hold your shares of our common stock through a bank, broker or other nominee and you wish to exercise appraisal rights, you should consult with your bank, broker or other nominee to determine the appropriate procedures for the making of a demand for appraisal on your behalf by your bank, broker or other nominee.

Other Matters

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

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on [•]

This proxy statement is available on the “Investor Relations” section of our website located at https://investors.Mandiant.com.

Householding of Special Meeting Materials

We have adopted a procedure approved by the SEC called “householding.” Under this procedure, stockholders who have the same address and last name will receive only one copy of this proxy statement unless one or more of these stockholders notifies us that they wish to continue receiving individual copies. This procedure reduces printing costs, postage fees and the use of natural resources. Each stockholder who participates in householding will continue to be able to access or receive a separate proxy card upon request. If you wish to receive a separate set of our disclosure documents at this time, please notify us by sending a written request to Investor Relations, Mandiant, Inc., 11951 Freedom Drive, 6th Floor, Reston, Virginia 20190 or by telephone at (703) 935-1700.

If you are a stockholder who has multiple accounts in your name or you share an address with other stockholders and would like to receive a single set of our disclosure documents for your household, you may notify your broker, if your shares are held in a brokerage account, or you may contact our Corporate Secretary using the contact method above, if you hold registered shares.

TABLE OF CONTENTS

THE MERGER

The rights and obligations of the parties to the merger agreement are governed by the specific terms and conditions of the merger agreement and not by any summary or other information provided in this proxy statement. Therefore, this discussion of the merger is qualified in its entirety by reference to the merger agreement, a copy of which is attached as Annex A to this proxy statement and incorporated into this proxy statement by reference. You should read the entire merger agreement carefully as it is the legal document that governs the merger.

Parties Involved in the Merger

Mandiant, Inc.
11951 Freedom Drive, 6th Floor
Reston, Virginia 20190
(703) 935-1700

Mandiant is a global cybersecurity company with a mission to protect our customers from cyber-attacks using innovative technology, intelligence and expertise from the front lines.

Our common stock is listed on the Nasdaq under the symbol “MNDT.”

Google LLC
1600 Amphitheatre Parkway
Mountain View, California 94043
(650) 253-0000

Dupin Inc.
1600 Amphitheatre Parkway
Mountain View, California 94043
(650) 253-0000

Effects of the Merger

Upon the terms and subject to the conditions of the merger agreement, and in accordance with the DGCL, at the effective time of the merger, (1) Merger Sub will merge with and into Mandiant; (2) the separate existence of Merger Sub will cease; and (3) Mandiant will continue as the surviving corporation in the merger and as a wholly owned subsidiary of Parent.

As a result of the merger, Mandiant will cease to be a publicly traded company, our common stock will be delisted from the Nasdaq and deregistered under the Exchange Act and Mandiant will no longer file periodic reports with the SEC. If the merger is completed, you will not own any shares of capital stock of the surviving corporation.

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

TABLE OF CONTENTS

Effect on Mandiant if the Merger is Not Completed

If the merger agreement is not adopted by our stockholders, or if the merger is not completed for any other reason, our stockholders will not receive any payment for their shares of our common stock in connection with the merger. Instead, (1) Mandiant will remain an independent public company; (2) our common stock will continue to be listed and traded on the Nasdaq and registered under the Exchange Act; and (3) we will continue to file periodic reports with the SEC. In addition, if the merger is not completed, we expect that: (1) our management will continue to operate the business as it is currently being operated; and (2) our stockholders will continue to be subject to the same risks and opportunities to which they are currently subject, including risks related to the highly competitive industry in which Mandiant operates and adverse economic conditions.

Furthermore, if the merger is not completed, and depending on the circumstances that cause the merger not to be completed, the price of our common stock may decline significantly.

Accordingly, there can be no assurance as to the effect of the merger not being completed on the future value of your shares of our common stock. If the merger is not completed, the Mandiant Board will continue to evaluate and review, among other things, Mandiant’s business, operations, strategic direction and capitalization, and will make whatever changes it deems appropriate. If the merger agreement is not adopted by our stockholders or if the merger is not completed for any other reason, Mandiant’s business, prospects or results of operation may be adversely impacted.

In specified circumstances in which the merger agreement is terminated, Mandiant has agreed to pay Parent (or its designee) the applicable termination fee. In other specified circumstances in which the merger agreement is terminated, Parent has agreed to pay Mandiant a termination fee.

Per Share Price

Upon the terms and subject to the conditions of the merger agreement, at the effective time of the merger:

•

each share of our common stock that is (1) held by Mandiant as treasury stock; (2) owned by Parent or Merger Sub; or (3) owned by any direct or indirect wholly owned subsidiary of Parent or Merger Sub, in each case, as of immediately prior to the effective time of the merger will be cancelled and extinguished without any conversion thereof or consideration paid therefor;

•

each share of our common stock that is issued and outstanding as of immediately prior to the effective time of the merger (other than the shares identified in the prior bullet and shares of our common stock held by our stockholders who have (1) neither voted in favor of the adoption of the merger agreement nor consented thereto in writing; and (2) properly and validly exercised their statutory rights of appraisal in respect of such shares in accordance with the DGCL) will be cancelled and extinguished and automatically converted into the right to receive cash in an amount equal to the per share price, without interest and less any applicable withholding taxes; and

•

each certificate formerly representing any shares of our common stock or any book-entry shares that represented shares of our common stock immediately prior to the effective time of the merger will automatically be cancelled and retired and all such shares will cease to exist and will thereafter only represent the right to receive the per share price, without interest and less any applicable withholding taxes.

On the closing date of the merger or the first business day following the closing date of the merger, a sufficient amount of cash will be deposited with a designated payment agent to pay the aggregate per share price. Once a stockholder has provided the payment agent with his, her or its stock certificates (or an affidavit of loss in lieu of a stock certificate) or customary agent’s message with respect to book-entry shares, appropriate letter of transmittal and other items specified by the payment agent, then the payment agent will pay the stockholder the appropriate portion of the aggregate per share price in exchange for shares of our common stock held by the stockholder. For more information, see the section of this proxy statement captioned “The Merger Agreement — Payment Agent, Exchange Fund and Exchange and Payment Procedures.”

TABLE OF CONTENTS

After the merger is completed, each of our stockholders will have the right to receive the per share price for each share of our common stock that such stockholder owned, as described in the section of this proxy statement captioned “The Merger Agreement — Conversion of Shares,” but will no longer have any rights as a Mandiant stockholder (except that our stockholders who properly and validly exercise and perfect, and do not validly withdraw or otherwise lose, their appraisal rights will have the right to receive payment for the “fair value” of their shares as determined pursuant to an appraisal proceeding contemplated by the DGCL as described in the section of this proxy statement captioned “— Appraisal Rights”).

Background of the Merger

The following chronology summarizes the key meetings and events that led to the signing of the merger agreement. This chronology does not purport to catalogue every conversation of or among the Mandiant Board, the Transaction Committee (as defined below), our representatives, or other parties.

The Mandiant Board regularly evaluates our strategic direction and ongoing business plans with a view toward strengthening our business and enhancing stockholder value. As part of this evaluation, the Mandiant Board has, from time to time, considered a variety of strategic alternatives. These have included, among others, (1) the continuation of, and potential improvements to, our current business plan, with Mandiant remaining an independent entity; (2) the investment in, and development of, new products and services; (3) capital raising activities; (4) potential expansion opportunities through partnerships or other commercial relationships; and (5) business combinations, acquisitions, dispositions and other financial and strategic alternatives.

In 2019, the Mandiant Board explored potential strategic alternatives available to our company, with a focus on a potential divestiture of our network, email, endpoint and cloud security products and the related security management and orchestration platform (which we refer to as the “FireEye Products business”). We retained Goldman Sachs to provide us with financial advisory services in this process. Goldman Sachs was well known to the Mandiant Board given Goldman Sachs’ qualifications, extensive expertise, international reputation, knowledge of our industry and experience in advising companies in connection with potential strategic transactions. The Mandiant Board ultimately determined not to pursue a strategic transaction at that time. As a result of this process, however, the Mandiant Board determined that the divestiture of the FireEye Products business was a potentially attractive alternative that could enhance long-term stockholder value. Our engagement of Goldman Sachs was not terminated following this decision, and Goldman Sachs continued to advise us from time to time.

On November 19, 2020, we announced a $400 million strategic investment in us by Blackstone and ClearSky. We used the proceeds of this investment, which closed on December 11, 2020, to support strategic growth initiatives. Following this investment, we leveraged Blackstone’s expertise as affiliates of a leading financial institution to support the transformation of our business.

In early 2021, we began, with the assistance of Goldman Sachs, to actively explore the sale of the FireEye Products business as a potential means of enhancing long-term stockholder value. To assist in this process (as well as any decision by the Mandiant Board to explore strategic alternatives for the entire company), on March 4, 2021, the Mandiant Board established a transaction committee (which we refer to as the “Transaction Committee”). The Mandiant Board formed the Transaction Committee in light of (1) the potentially significant workload that could be involved in any decision by Mandiant to sell the FireEye Products business or to consider other strategic alternatives; (2) the possibility that Mandiant management may need feedback and direction on relatively short notice; and (3) the benefits and convenience of having a subset of directors oversee and direct the process of considering strategic alternatives. The Mandiant Board authorized the Transaction Committee to, among other things, (1) consider, analyze and evaluate strategic alternatives available to the company; (2) approach potential strategic and financial acquirers regarding strategic alternatives, and to negotiate with such parties; (3) oversee and provide assistance to Mandiant management and our advisers with respect to the consideration, analysis and evaluation of any strategic alternative; (4) take all other actions that the Transaction Committee deemed necessary, appropriate or desirable; and (5) recommend to the Mandiant Board what action, if any, should be taken with respect to any strategic alternative. The Mandiant Board retained the power and authority to approve the final decision on pursuing a strategic alternative. It was also understood that the Mandiant Board would continue to have an active role in the consideration of strategic alternatives. The Mandiant Board appointed

TABLE OF CONTENTS

Kimberly Alexy, Viral Patel and Enrique Salem as the members of the Transaction Committee. The Mandiant Board did not provide for the payment of any compensation to the members of the Transaction Committee in consideration of their service on the committee (other than their compensation as members of the Mandiant Board).

On June 2, 2021, we announced our intention to sell the FireEye Products business to affiliates of Symphony Technology Group. We refer to this transaction as the “FireEye Divestiture.”

During June 2021 and July 2021, Kevin Mandia, our chief executive officer, spoke, on an individual basis, with members of the Mandiant Board about the possibility and advisability of exploring other strategic alternatives for Mandiant following the completion of the FireEye Divestiture, including a possible sale of Mandiant. The members of the Mandiant Board expressed support for Mr. Mandia having introductory conversations with a limited number of strategic and financial acquirers who were most likely to have an interest in an acquisition of us. Mr. Mandia subsequently engaged in these discussions. Due to Mr. Mandia and other members of Mandiant management being focused on executing the FireEye Divestiture, these discussions did not advance beyond the introductory stage until late September 2021.

On September 22, 2021, Mr. Mandia spoke with members of management of a potential strategic acquirer (which we refer to as “Strategic A”) concerning Strategic A’s possible interest in considering an acquisition of us.

On October 4, 2021, in connection with the pending FireEye Divestiture, our company was renamed Mandiant.

On October 8, 2021, we completed the FireEye Divestiture, at which time our business became focused entirely on our controls-agnostic cybersecurity solutions and services.

On October 11, 2021, members of Mandiant management met with representatives of a potential financial acquirer (which we refer to as “Financial A”) concerning Financial A’s possible interest in considering an acquisition of us. This meeting occurred at Financial A’s request.

Also on October 11, 2021, Mr. Mandia spoke with a member of management of a potential strategic acquirer (which we refer to as “Strategic B”) concerning Strategic B’s possible interest in considering an acquisition of us.

On October 19, 2021, Mr. Mandia spoke with members of management of Strategic B concerning Strategic B’s possible interest in considering an acquisition of us.

On October 22, 2021, Frank Verdecanna, our chief financial officer, spoke with a member of management of Strategic B concerning our business and prospects.

On October 23, 2021, Mr. Mandia spoke with a member of management of Strategic B concerning Strategic B’s possible interest in considering an acquisition of us.

On October 24, 2021, Mr. Mandia spoke with a representative of Financial A concerning Financial A’s possible interest in considering an acquisition of us.

On November 3, 2021, members of Mandiant management met with members of management of Strategic B concerning our business and prospects.

On November 9, 2021, members of Mandiant management met with members of management of Strategic A concerning our business and prospects.

On November 17, 2021, Mr. Mandia spoke with a member of management of a potential strategic acquirer (which we refer to as “Strategic C”) concerning Strategic C’s possible interest in considering an acquisition of us.

Also on November 17, 2021, members of Mandiant management met with members of management of Strategic A concerning our business and prospects.

TABLE OF CONTENTS

In mid-November 2021, it was determined that sufficient interest in an acquisition of us had been expressed to warrant the involvement of Goldman Sachs to assist the Mandiant Board in considering strategic alternatives for Mandiant.

On December 7, 2021, members of the Mandiant Board and members of Mandiant management met informally with representatives of Goldman Sachs. During this meeting, the representatives of Goldman Sachs provided their perspective on market conditions and mergers and acquisitions activity in the cybersecurity and technology space, and also discussed Goldman Sachs’ preliminary views on our stock price performance and compared it to certain other companies and the broader market. The representatives of Goldman Sachs discussed strategic alternatives available to Mandiant, including (1) the continuation of our current business plan with Mandiant remaining as an independent company; and (2) a sale of Mandiant. As part of this discussion, the representatives of Goldman Sachs provided Goldman Sachs’ preliminary view, in its judgment and experience, as to the most likely potential strategic and financial acquirers of Mandiant based on, among other things, Goldman Sachs’ assessment of (1) the strategic fit of Mandiant with each potential acquirer; and (2) the ability and likelihood of each potential acquirer to engage in, and consummate, an acquisition of us. After considering our near- and long-term prospects as an independent company, it was the consensus of the members of the Mandiant Board participating in the discussion that (1) a sale of Mandiant in the near term could be in the best interests of Mandiant and our stockholders; (2) a more formalized review of our strategic alternatives should commence; (3) it was appropriate to use a targeted, private process focused on the potential strategic and financial acquirers most likely to have an interest in acquiring us; (4) Goldman Sachs should make initial or renewed contact with the most likely potential strategic acquirers (including Parent, Strategic A, Strategic B and Strategic C) and financial acquirers (including Financial A) regarding their interest in an acquisition of us; (5) depending on the outcome of these contacts by Goldman Sachs, it would be appropriate for Mandiant management to proceed with more in-depth discussions with these parties concerning a possible acquisition of us; and (6) the Transaction Committee should oversee this process.

Following the December 7, 2021 meeting, we began a more formalized process of reviewing strategic alternatives. During this process, Goldman Sachs, as directed and on our behalf, ultimately contacted seven potential strategic acquirers and five potential financial acquirers regarding their interest in considering an acquisition of us. In support of the process, representatives of Goldman Sachs discussed Mandiant from time to time with potential strategic and financial acquirers in order to better understand their interest in an acquisition of us. We also entered into, or were already a party to, confidentiality agreements with all seven potential strategic acquirers and four of the potential financial acquirers. Certain of these confidentiality agreements contained a “standstill” provision; none of these confidentiality agreements prohibited the counterparty from making a public or private proposal to acquire all of our common stock. Two of the seven potential strategic acquirers (one of which was Strategic C) and one of the potential financial acquirers did not pursue any further engagement in respect of an acquisition of us.

On December 8, 2021, Mr. Mandia spoke with a senior executive of Financial A concerning Financial A’s interest in a possible acquisition of us.

On December 15, 2021, members of Mandiant management met with members of management of Strategic A to discuss general due diligence matters.

Also on December 15, 2021, members of Mandiant management gave a management presentation regarding our company to Strategic B.

Also on December 15, 2021, the Mandiant Board met, with members of Mandiant management in attendance. During the meeting, Mr. Verdecanna provided a general update on the current status of our exploration of potential strategic alternatives.

On December 17, 2021, members of Mandiant management gave a management presentation regarding our company to Parent.

On December 20, 2021, Mr. Mandia spoke with a senior executive of Strategic B concerning Strategic B’s interest in a possible acquisition of us.

TABLE OF CONTENTS

Also on December 20, 2021, members of Mandiant management gave a management presentation regarding our company to a potential strategic acquirer (which we refer to as “Strategic D”).

On December 23, 2021, members of Mandiant management gave a management presentation regarding our company to a potential strategic acquirer (which we refer to as “Strategic E”).

Also on December 23, 2021, the Transaction Committee determined to hold weekly committee meetings, with all Mandiant Board members being invited to such meetings.

On December 26, 2021, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers and the relative level of acquisition interest that each was then displaying.

On January 4, 2022, Mr. Mandia spoke with a senior executive of a potential financial acquirer (which we refer to as “Financial B”) concerning Financial B’s possible interest in an acquisition of us. This meeting occurred at Financial B’s request.

On January 5, 2022, representatives of Strategic E informed representatives of Goldman Sachs that Strategic E was no longer considering an acquisition of us.

On January 6, 2022, members of Mandiant management met with members of management of Strategic B to discuss due diligence matters relating to our consulting business.

Also on January 6, 2022, members of Mandiant management gave a management presentation regarding our company to Financial B.

On January 7, 2022, members of Mandiant management met with members of management of Strategic B to discuss due diligence matters relating to our platform business.

Also on January 7, 2022, members of Mandiant management met with members of management of Parent to discuss due diligence matters relating to our consulting business.

On January 9, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers. It was noted that Financial A had requested to work with two other potential financial acquirers (which we refer to as “Financial C” and “Financial D,” respectively) in connection with jointly considering a possible acquisition of us. The Transaction Committee approved this request.

On January 11, 2022, members of Mandiant management met with members of management of Strategic B to discuss due diligence matters relating to our platform business.

Also on January 11, 2022, the Mandiant Board met, with members of Mandiant management in attendance. Mandiant management reviewed with the Mandiant Board a preliminary draft of four years of financial projections (which would later be used in preparing the Projected Financial Information) and described, among other things, the process for preparing the preliminary financial projections, including the underlying assumptions and various execution and other risks to realizing the forecasted results. (The term Projected Financial Information is defined in, and further information about the substance of the Projected Financial Information is contained in, the section of this proxy statement captioned “— Projected Financial Information.”) The Mandiant Board approved these preliminary financial projections and authorized Mandiant management to share them with (1) Goldman Sachs for purposes of Goldman Sachs’ financial analysis of Mandiant and (2) potential acquirers.

On January 12, 2022, members of Mandiant management met with members of management of Strategic A to discuss due diligence matters related to our consulting business.

Also on January 12, 2022, members of Mandiant management met with members of management of Parent to discuss due diligence matters related to our products and technology.

TABLE OF CONTENTS

On January 14, 2022, members of Mandiant management met with members of management of Strategic A to discuss due diligence matters related to our products and technology.

Also on January 14, 2022, members of Mandiant management met with members of management of Strategic B to discuss financial due diligence matters.

Also on January 14, 2022, members of Mandiant management met with members of management of Strategic D to discuss due diligence matters related to our products and technology.

Also on January 14, 2022, members of Mandiant management met with members of management of Parent to discuss financial due diligence matters.

On January 16, 2022, the Mandiant Board met, with members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers.

On January 18, 2022, members of Mandiant management gave a management presentation regarding our company to Financial D.

Also on January 18, 2022, members of Mandiant management met with members of management of Strategic A to discuss financial due diligence matters.

On January 19, 2022, members of Mandiant management met with representatives of each of Financial A, Financial C and Financial D to discuss financial, products and technology due diligence matters.

On January 20, 2022, the Mandiant Board met, with members of Mandiant management and a representative of Wilson Sonsini Goodrich & Rosati, Professional Corporation (which we refer to as “Wilson Sonsini”), outside legal counsel to Mandiant, in attendance. A member of the Transaction Committee and members of Mandiant management provided a general update on the status of discussions with potential strategic and financial acquirers.

On January 21, 2021, we opened an online data room for the purpose of allowing interested parties to conduct due diligence on Mandiant. At this time, only Financial A, Financial B, Financial C and Financial D were granted access to the data room.

On January 21, 2022, members of Mandiant management met with members of management of Strategic A to discuss due diligence matters related to our managed services.

Also on January 21, 2022, members of Mandiant management met with members of management of Parent to discuss due diligence matters related to our products.

On January 23, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers.

On January 27, 2022, members of Mandiant management met with representatives of Financial A, Financial C and Financial D to discuss due diligence matters related to our products.

On January 28, 2022, members of Mandiant management met with representatives of Financial A, Financial C and Financial D to discuss our business and prospects.

On January 30, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers.

On February 1, 2022, members of Mandiant management met with members of management of Parent to discuss go-to-market and financial due diligence matters.

TABLE OF CONTENTS

On February 2, 2022, Mr. Mandia spoke with a senior executive of Strategic B concerning the status of Strategic B’s interest in a possible acquisition of us.

Also on February 2, 2022, members of Mandiant management met with representatives of Financial A, Financial C and Financial D to discuss due diligence matters related to our products business.

On February 4, 2022, representatives of Strategic D informed representatives of Goldman Sachs that Strategic D was no longer considering an acquisition of us.

On February 6, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic and financial acquirers.

On February 7, 2022, representatives of Financial A informed representatives of Goldman Sachs that Financial A, Financial C and Financial D were no longer considering an acquisition of us.

On February 8, 2022, Bloomberg published an article stating that Microsoft Corporation was in talks to acquire us.

On February 9, 2022, representatives of Financial B informed representatives of Goldman Sachs that Financial B was no longer considering an acquisition of us.

Also on February 9, 2022, members of Mandiant management met with members of management of Parent to discuss financial due diligence matters.

On February 10, 2022, Mr. Mandia spoke with a senior executive of Parent concerning Parent’s interest in a possible acquisition of us.

Also on February 10, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic acquirers, and noted that that all five of the potential financial acquirers contacted during our review of strategic alternatives had ceased discussions with us regarding an acquisition.

On February 11, 2022, Mr. Mandia spoke with a senior executive of Strategic A concerning the status of Strategic A’s interest in a possible acquisition of us.

On February 13, 2022, Mr. Mandia spoke with a senior executive of Parent concerning the status of Parent’s interest in a possible acquisition of us.

Also on February 13, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided a general update on the status of discussions with potential strategic acquirers. The Transaction Committee approved the distribution by Goldman Sachs of a bid process letter to Parent, Strategic A and Strategic B, which were the only parties that were still in active discussions regarding an acquisition of us. The bid process letters requested written acquisition proposals no later than February 21, 2022. Representatives of Goldman Sachs distributed these letters later that day.

On February 14, 2022, Mr. Mandia spoke to a senior executive of Parent concerning the status of Parent’s interest in a possible acquisition of us.

On February 15, 2022, members of Mandiant management met with members of management of Parent to discuss due diligence matters.

Also on February 15, 2022, members of Mandiant management met with members of Strategic A management to discuss due diligence matters.

On February 16, 2022, Mr. Mandia spoke with senior executives of Parent concerning Parent’s interest in a possible acquisition of us.

TABLE OF CONTENTS

On February 16, 2022, the Transaction Committee met, with members of the Mandiant Board and members of Mandiant management in attendance. Members of Mandiant management provided a general update on the status of discussions with Parent, Strategic A and Strategic B, noting that each continued to consider an acquisition. Members of Mandiant management reviewed with the Mandiant Board a draft of the Projected Financial Information for the period of 2022 to 2035 and described, among other things, the process for preparing the Projected Financial Information, including the underlying assumptions and various execution and other risks to realizing the Projected Financial Information. The Transaction Committee approved the Projected Financial Information, as well as its use by Goldman Sachs for purposes of performing its financial analyses in connection with rendering its fairness opinion to the Mandiant Board (as described in more detail in the section of this proxy statement captioned “— Opinion of Goldman Sachs & Co. LLC”).

On February 17, 2022, Mr. Mandia spoke with a senior executive of Strategic A concerning Strategic A’s possible interest in an acquisition of us.

Also on February 17, 2022, Mr. Mandia spoke with a senior executive of Strategic B concerning Strategic B’s possible interest in an acquisition of us.

On February 18, 2022, members of Mandiant management met with members of management of Parent to discuss engineering due diligence matters.

Also on February 18, 2022, members of Mandiant management met with members of Strategic A management to discuss our business and prospects.

On February 19, 2022, Goldman Sachs provided Mandiant with customary relationship disclosures regarding Goldman Sachs’ relationships with Parent, Strategic A and Strategic B.

On February 20, 2022, a senior executive of Strategic A spoke with representatives of Goldman Sachs and expressed interest in continuing to review information regarding Mandiant. The representatives of Goldman Sachs informed the senior executive of Strategic A that all parties in the process had been provided with generally consistent levels of information at that point and encouraged the senior executive of Strategic A to speak with Mr. Mandia that day to the extent that such discussion would be helpful to Strategic A. The representatives of Goldman Sachs further suggested that if Strategic A were interested in acquiring Mandiant, then Strategic A should submit a written acquisition proposal by the bid deadline on February 21, 2022, given the possibility that the Mandiant Board could decide at that point not to engage further with parties who had not submitted a written proposal. The senior executive of Strategic A acknowledged this suggestion and expressed interest in speaking further with Mr. Mandia.

Later on February 20, 2022, the senior executive of Strategic A spoke to Mr. Mandia and representatives of Goldman Sachs. The representatives of Goldman Sachs reiterated the importance of Strategic A submitting a written acquisition proposal by the bid deadline of February 21, 2022, if Strategic A were interested in a potential acquisition, given the possibility that the Mandiant Board could determine not to engage further with parties who had not submitted a timely written proposal. The senior executive of Strategic A again acknowledged this suggestion.

Also on February 20, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The representatives of Goldman Sachs provided the Transaction Committee, for the information of the Transaction Committee and the Mandiant Board, materials that summarized, based on theoretical models, the potential effects of the announcement and of the consummation of an acquisition of us on the capped call transactions that we had entered into with Goldman Sachs and other counterparties, each acting as principal for its own account, with respect to our convertible notes, as well as the relationship disclosures previously provided by Goldman Sachs. The Transaction Committee did not identify any concerns with these disclosures. The representatives of Goldman Sachs reviewed Goldman Sachs’ preliminary financial analyses of Mandiant. The Transaction Committee discussed next steps if we were to receive an acquisition proposal.

On February 21, 2022, Mr. Mandia spoke with a senior executive of Parent. During this discussion, the senior executive of Parent stated that Parent would be submitting a non-binding written proposal to acquire us.

TABLE OF CONTENTS

Also on February 21, 2022, Parent submitted a non-binding written proposal to acquire us for $22.00 in cash per share of our common stock. Parent also requested that we agree to negotiate exclusively with Parent through March 19, 2022.

Also on February 21, 2022, a senior executive of Strategic A informed representatives of Goldman Sachs that, although Strategic A would not be submitting an acquisition proposal on that date, it remained interested in considering an acquisition of us.

On February 22, 2022, representatives of Strategic B informed Mr. Mandia that Strategic B was no longer considering an acquisition of us.

Later on February 22, 2022, the Mandiant Board met, with members of Mandiant management and representatives of each of Goldman Sachs and Wilson Sonsini in attendance. The results of the strategic review process overseen by Goldman Sachs were noted, including that only Parent and Strategic A were still considering an acquisition of us in any respect. The terms of the acquisition proposal submitted by Parent (including the request to negotiate on an exclusive basis), and the recent communication from Strategic A, were discussed. The Mandiant Board noted (1) the significant due diligence already undertaken by Parent; (2) Parent’s desire to proceed quickly toward announcement of an acquisition; (3) the more limited due diligence that had been undertaken by Strategic A as compared to Parent; (4) Strategic A’s failure to provide a written acquisition proposal by the bid deadline of February 21, 2022; (5) the possibility that Parent would withdraw its acquisition proposal if it was not promptly accepted by Mandiant; and (6) the perceived level of strategic fit, as well as regulatory considerations and deal certainty, with respect to Parent compared to Strategic A. Given these considerations, the Mandiant Board determined that it wished to continue to work toward a transaction with Parent. The Mandiant Board instructed Goldman Sachs to make a counterproposal to Parent for an acquisition of us for $24.00 in cash per share of our common stock, with an exclusive negotiation period ending on March 9, 2022. The Transaction Committee also requested a conversation between Enrique Salem, our chairman of the board, Mr. Mandia and Sundar Pichai, Parent’s chief executive officer, to discuss Parent’s institutional commitment to the acquisition. Mr. Mandia confirmed to the Mandiant Board that neither he nor any member of Mandiant management had engaged in discussions with Parent regarding any post-acquisition employment terms with Parent. The Mandiant Board also authorized the Transaction Committee to oversee negotiations with Parent and, if it determined appropriate, to authorize us to enter into an exclusivity agreement with Parent.

Following the meeting of the Mandiant Board, representatives of Goldman Sachs informed members of management of Parent of the counterproposal from the Mandiant Board. Later, in a subsequent conversation with representatives of Goldman Sachs, Parent agreed to increase its acquisition proposal to $23.00 in cash per share of our common stock and to shorten the exclusivity period to end at 6:00 a.m., Pacific time, on March 10, 2022. Parent also agreed to arrange the requested call between Messrs. Salem, Mandia and Pichai.

Later on February 22, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The Transaction Committee discussed the terms of the latest acquisition proposal from Parent and agreed to meet again when Parent provided its revised proposal in writing and its updated exclusivity agreement.

Following the meeting of the Transaction Committee, representatives of Goldman Sachs received multiple calls from a senior executive of Strategic A. In these calls, the senior executive of Strategic A (1) stated that Strategic A remained interested in considering an acquisition of us; and (2) requested assistance in thinking about an appropriate price for an acquisition. The representatives of Goldman Sachs declined to provide such assistance, but stated that they would convey Strategic A’s interest to Mandiant.

Later on February 22, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of each of Goldman Sachs and Wilson Sonsini in attendance. A representative of Wilson Sonsini reviewed with the members of the Transaction Committee their fiduciary duties. It was noted that the requested call between Messrs. Salem, Mandia and Pichai had been arranged and would be occurring shortly. The representatives of Goldman Sachs described their recent discussions with a senior executive of Strategic A. The Transaction Committee noted the same factors regarding Parent and Strategic A that were noted in the meeting of the Mandiant Board earlier

TABLE OF CONTENTS

in the day. The Transaction Committee directed Goldman Sachs to inform Strategic A that it should submit a written acquisition proposal not later than that evening, and that the per share price in any such proposal should reflect a premium of well above 50 percent over our stock price prior to speculation that we were pursuing a sale process. Such a premium would imply a price of well above $22.59 per share of our common stock, although representatives of Goldman Sachs did not provide this number to Strategic A. Messrs. Mandia and Salem then departed the meeting to speak with Mr. Pichai.

Following the meeting of the Transaction Committee, representatives of Goldman Sachs informed a senior executive of Strategic A as instructed by the Transaction Committee. The senior executive of Strategic A informed the representatives of Goldman Sachs that Strategic A would further consider an acquisition of us and would respond that evening.

Still later on February 22, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of Goldman Sachs in attendance. The terms of Parent’s acquisition proposal at $23.00 in cash per share of our common stock (which by this time had been put in writing), including the updated exclusivity agreement, were discussed. Messrs. Salem and Mandia discussed their conversation with Mr. Pichai and noted their satisfaction with the level of institutional commitment to the acquisition expressed by Mr. Pichai. The representatives of Goldman Sachs departed the meeting to take a call from the senior executive of Strategic A. During this call, the senior executive of Strategic A stated that Strategic A was unable to submit an acquisition proposal that evening. The representatives of Goldman Sachs rejoined the meeting and informed the Transaction Committee of the conversation with Strategic A. The Transaction Committee determined to move forward with the acquisition proposal from Parent and to agree to negotiate with Parent on an exclusive basis through 6:00 a.m., Pacific time, on March 10, 2022. Parent and Mandiant subsequently entered into an exclusivity agreement.

Beginning on February 23, 2022, Parent and its advisors were granted access to legal and operational due diligence documents and information in an electronic data room to support their due diligence review of Mandiant. Over the following days, members of management of Parent and representatives of Parent’s advisors conducted operational, legal, financial, accounting, employment and other due diligence on Mandiant. At various points, members of management of Parent and representatives of Parent’s advisors met with Mandiant management and our advisors regarding due diligence information, potential synergies, employee retention and related matters.

On February 23, 2022, a draft of the merger agreement was provided to Parent and its legal advisors at Freshfields Bruckhaus Deringer US LLP (which we refer to as “Freshfields”). Over the following two weeks, Mandiant management and Parent management, and representatives of their respective legal advisors, negotiated the terms of the merger agreement. Key terms of the merger agreement negotiated by the parties included (1) the nature and scope of Parent’s obligations to secure necessary regulatory approvals for the acquisition; (2) the amount of the termination fee payable by each party and the circumstances in which it would be payable; (3) whether Mandiant was obligated to pay Parent a termination fee if our stockholders did not approve the merger; (4) the definition of “material adverse effect”; (5) the conditions to each party’s obligation to consummate the merger; and (6) the nature and scope of the interim operating covenants applicable to Mandiant during the period prior to the closing of the merger.

On February 27, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of each of Goldman Sachs and Wilson Sonsini in attendance. A representative of Wilson Sonsini summarized the material terms of the merger agreement and the points that were under negotiation.

Also on February 27, 2022, representatives of Goldman Sachs received a call from a senior executive of Strategic A seeking an update on any sale process involving Mandiant. The representatives of Goldman Sachs, in compliance with the exclusivity agreement then in effect, declined to give such an update at such time.

On February 28, 2022, Freshfields provided a draft of the form of the voting agreements to representatives of Wilson Sonsini. Over the following days, representatives of Mr. Mandia, Blackstone, ClearSky, Mandiant and Parent negotiated the terms of the voting agreement.

TABLE OF CONTENTS

On March 2, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of each of Goldman Sachs, Wilson Sonsini and Baker Botts LLP (which we refer to as “Baker Botts”), outside antitrust counsel to Mandiant, in attendance. The material terms of the merger agreement and the points that remained under negotiation were discussed, along with the nature of the regulatory approvals needed for the merger.

On March 6, 2022, the Transaction Committee met, with other members of the Mandiant Board, members of Mandiant management and representatives of each of Goldman Sachs and Wilson Sonsini in attendance. The material terms of the merger agreement and the points that remained under negotiation were discussed; it was noted that the material economic and valuation terms had been agreed in principle. In response to a specific request from Parent, the Transaction Committee authorized Mr. Mandia (and only Mr. Mandia) to begin discussions with Parent concerning the terms of his employment with Parent following the merger.

Later on March 6, 2022, Freshfields provided a draft of Mr. Mandia’s non-competition agreement to Wilson Sonsini, which agreement was then shared with Mr. Mandia and his counsel.

On March 7, 2022, Mr. Mandia received a draft employment offer from Parent.

Later on March 7, 2022, The Information published an article stating that Parent was in talks to acquire us.

Still later on March 7, 2022 the Mandiant Board met, with members of Mandiant management and representatives of each of Goldman Sachs, Wilson Sonsini and Baker Botts in attendance. A representative of Wilson Sonsini reviewed with the Mandiant Board their fiduciary duties. A representative of Wilson Sonsini also reviewed the principal terms of the merger agreement, the voting agreements and the other transaction documents. A representative of Baker Botts discussed the terms of the merger agreement related to antitrust and competition law matters. Mr. Mandia updated the Mandiant Board on the nature of the non-competition obligations that Parent was requiring of him, and noted that negotiations with Parent were continuing with respect to the terms of his employment following the merger. The representatives of Goldman Sachs reviewed with the Mandiant Board Goldman Sachs’ financial analyses of the consideration to be paid to stockholders in connection with the merger. The representatives of Goldman Sachs then rendered the oral opinion of Goldman Sachs, subsequently confirmed by delivery of its written opinion dated March 7, 2022, to the Mandiant Board that, as of the date of the written opinion and based upon and subject to the factors and assumptions set forth therein, the $23.00 in cash per share of our common stock to be paid to the holders (other than Parent and its affiliates) of shares of our common stock pursuant to the merger agreement was fair from a financial point of view to the holders of such shares.

Still later on March 7, 2022, the merger agreement, voting agreements and other transaction documents were finalized.

Even later on March 7, 2022, the Mandiant Board met, with members of Mandiant management and representatives of each of Goldman Sachs, Wilson Sonsini and Baker Botts in attendance. A representative of Wilson Sonsini reviewed the terms of the final merger agreement, voting agreement and other transaction documents with the Mandiant Board. The representatives of Goldman Sachs confirmed the oral opinion of Goldman Sachs, subsequently confirmed by delivery of a written opinion dated March 7, 2022, to the Mandiant Board that, as of the date of the written opinion and based upon and subject to the factors and assumptions set forth therein, the $23.00 in cash per share of our common stock be paid to the holders (other than Parent and its affiliates) of shares of our common stock, pursuant to the merger agreement, was fair from a financial point of view to the holders of such shares. The Mandiant Board, after considering the factors more fully described in the section of this proxy statement captioned “— Recommendation of the Mandiant Board and Reasons for the Merger,” (1) determined that it was in the best interests of Mandiant and its stockholders, and declared it advisable, to enter into the merger agreement providing for the merger in accordance with the DGCL upon the terms and subject to the conditions set forth in the merger agreement; (2) approved the execution and delivery of the merger agreement by Mandiant, the performance by Mandiant of its covenants and other obligations in the merger agreement, and the consummation of the merger upon the terms and subject to the conditions set forth in the merger agreement; (3) directed that the adoption of the merger agreement be submitted to a vote of our stockholders; (4) resolved to recommend

TABLE OF CONTENTS

that our stockholders vote in favor of the adoption of the merger agreement and the approval of the merger in accordance with the DGCL; and (5) approved the voting agreements.

Even later on March 7, 2022, the merger agreement and voting agreements, and Mr. Mandia’s non-competition agreement, were signed by the respective parties.

Early on March 8, 2022, before the opening of trading on Nasdaq, we publicly disclosed our entry into the merger agreement and the voting agreements.

Recommendation of the Mandiant Board and Reasons for the Merger

Recommendation of the Mandiant Board

On March 7, 2022, the Mandiant Board unanimously: (1) determined that it was in the best interests of Mandiant and its stockholders, and declared it advisable, to enter into the merger agreement providing for the merger in accordance with the DGCL upon the terms and subject to the conditions set forth in the merger agreement; (2) approved the execution and delivery of the merger agreement by Mandiant, the performance by Mandiant of its covenants and other obligations in the merger agreement, and the consummation of the merger upon the terms and subject to the conditions set forth in the merger agreement; (3) directed that the adoption of the merger agreement be submitted to a vote of Mandiant’s stockholders at a meeting thereof; (4) resolved to recommend that our stockholders vote in favor of the adoption of the merger agreement and the approval of the merger in accordance with the DGCL; and (5) approved the voting agreements and the transactions contemplated thereby.

Reasons for the Merger

In evaluating the merger agreement and the merger, the Mandiant Board consulted with Mandiant management, as well as representatives of each of Goldman Sachs, Wilson Sonsini and Baker Botts. In recommending that Mandiant stockholders vote “FOR” the adoption of the merger agreement, the Mandiant Board considered and analyzed a number of factors, including the following (which factors are not necessarily presented in order of relative importance). Based on these consultations, considerations and analyses, and the factors discussed below, the Mandiant Board concluded that entering into the merger agreement was advisable and in the best interests of Mandiant and our stockholders.

The Mandiant Board believed that the following material factors and benefits supported its determination and recommendation:

•

Financial Condition, Results of Operations and Prospects of Mandiant; Risks of Execution. The current, historical and projected financial condition, results of operations and business of Mandiant, as well as Mandiant’s prospects and risks if it were to remain an independent company. In particular, the Mandiant Board considered Mandiant’s long-term operating plan (as reflected in the Projected Financial Information). As part of this, the Mandiant Board considered the potential opportunities that Mandiant’s long-term operating plan presented against, among other things, various execution and other risks to achieving the long-term operating plan and related uncertainties, including: (1) the risks and uncertainties associated with achieving and executing Mandiant’s current business plan and long-term operating plan in the short and long term; (2) the impact of market, customer and competitive trends on Mandiant; and (3) the general risks related to market conditions that could reduce the price of our common stock. Among the potential risks identified by the Mandiant Board were:

•

Mandiant’s competitive positioning and prospects as an independent company. Included among these risks were consideration of (1) Mandiant’s size, as well as its financial resources, relative

TABLE OF CONTENTS

to those of its competitors; (2) new and evolving competitive threats; and (3) the substantial risks to achieving Mandiant’s long-term operating plan.

•

The difficulty of implementing the various business transformation initiatives currently being undertaken, and anticipated to be undertaken, by Mandiant, including in respect of efforts to improve our cost structure. The Mandiant Board noted that these initiatives required sustained effort on our part and were not certain to result in a more valuable company.

•

Investments required to implement new systems to further drive Mandiant’s business, including the need for a new enterprise resource planning system.

•

The challenges of making investments to achieve long-term growth prospects for a publicly traded company, which is subject to scrutiny based on its quarterly performance. The Mandiant Board was aware that the price of our common stock could be negatively impacted if Mandiant failed to meet investor expectations, including if Mandiant failed to meet its growth objectives.

•

The historical execution of Mandiant’s business plan by Mandiant management and their ability to continue to drive Mandiant’s business. In this regard, the Mandiant Board was aware that Mr. Verdecanna had announced his intention to retire in 2022, and this retirement followed the departure of other senior executives.

•

The continued business and economic uncertainty related to the COVID-19 pandemic and the possibility that business conditions — for Mandiant and the larger economy — will not improve and could get worse.

•

Results of Strategic Review Process. The merger was the result of an extensive strategic review process overseen by the Transaction Committee. The Mandiant Board considered that seven potential strategic acquirers (including Parent) and five potential financial acquirers were contacted concerning their interest in an acquisition of Mandiant. The Mandiant Board considered the nature of the engagement by each of these potential acquirers over several weeks, and that only Parent had submitted an acquisition proposal. The Mandiant Board also was aware of the media reports regarding a potential sale of Mandiant that began on February 8, 2022, and noted that, following such media reports, no additional strategic or financial acquirers contacted Mandiant about pursuing an acquisition.

•

Certainty of Value. The consideration to be received by our stockholders in the merger consists entirely of cash, which provides certainty of value measured against the ongoing business and financial execution risks of Mandiant’s long-term operating plan. The receipt of cash consideration eliminates uncertainty and risk for our stockholders related to the continued execution of Mandiant’s business plan. In that regard, the Mandiant Board noted that Mandiant’s stock price could be negatively impacted if we failed to meet investor expectations.

•

Best Value Reasonably Available; Potential Strategic Alternatives. The Mandiant Board believed that the per share merger consideration represents the best value reasonably available for the shares of our common stock, taking into account the other strategic alternatives available to Mandiant, including continue to execute on our business plan as an independent company. The Mandiant Board determined that none of the possible alternatives to the merger (including the possibility of continuing to operate Mandiant as an independent company or pursuing a different transaction, and the desirability and perceived risks of those alternatives, as well as the potential benefits and risks to Mandiant’s stockholders of those alternatives and the timing and likelihood of effecting such alternatives) was reasonably likely to present superior opportunities for us to create greater value for our stockholders, taking into account execution risks as well as business, competitive, financial, industry, legal, market and regulatory risks. The Mandiant Board also considered that the per share merger consideration constitutes (1) a premium of approximately 53 percent to the closing price of our common stock on February 7, 2022, which was the last full trading day before media reports regarding a potential sale of Mandiant; and (2) a premium of approximately 57 percent to Mandiant’s unaffected 10-day volume-weighted average price as of February 7, 2022.

•

Fairness Opinion of Goldman Sachs. The oral opinion of Goldman Sachs rendered to the Mandiant Board, subsequently confirmed in writing by delivery of a written opinion dated March 7, 2022, that,

TABLE OF CONTENTS

as of the date of such written opinion and based upon and subject to the factors and various assumptions made, procedures followed and limitations and qualifications set forth therein, the $23.00 in cash per share of our common stock to be paid to the holders (other than Parent and its affiliates) of shares of our common stock, pursuant to the merger agreement, was fair from a financial point of view to the holders of such shares The opinion is more fully described in the section of this proxy statement captioned “— Opinion of Goldman Sachs & Co. LLC” and the full text of the opinion is attached as Annex C to this proxy statement.

•

Negotiations with Parent and Terms of the Merger Agreement. The terms of the merger agreement, which was the product of arms’-length negotiations, and the belief of the Mandiant Board that the merger agreement contained terms that provided Mandiant with a high level of closing certainty. The factors considered included:

•

Mandiant’s ability, under certain circumstances, to furnish information to, and conduct negotiations with, third parties regarding alternative acquisition proposals.

•

The Mandiant Board’s belief that the terms of the merger agreement would be unlikely to deter third parties from making a superior proposal.

•

The Mandiant Board’s ability, under certain circumstances, to withdraw or modify its recommendation that our stockholders vote in favor of the adoption of the merger agreement.

•

The Mandiant Board’s ability, under certain circumstances, to terminate the merger agreement to enter into a definitive alternative acquisition agreement. In that regard, the Mandiant Board believed that the termination fee payable by Mandiant in such instance was reasonable, consistent with or below similar fees payable in comparable transactions, and not preclusive of other offers.

•

The limited conditions to Parent’s obligation to consummate the merger, making the merger reasonably likely to be consummated.

•

The termination fee payable by Parent, in an amount ranging from $328,000,000 to $460,000,000; this fee is payable to Mandiant in certain circumstances, including if the necessary regulatory approvals to consummate the merger by the termination date (as it may be extended under the merger agreement) are not obtained.

•

No Financing Condition. Consummation of the merger is not subject to a financing condition. In addition, Parent represented in the merger agreement that it will have sufficient funds to consummate the merger.

•

Business Reputation of Parent. The business reputation and financial resources of Parent and its parent company, Alphabet Inc. The Mandiant Board believed that these factors supported the conclusion that a transaction with Parent could be completed quickly and in an orderly manner, and had a substantial likelihood of being consummated successfully.

•

Appraisal Rights. The appraisal rights in connection with the merger available to our stockholders who timely and properly exercise such appraisal rights under the DGCL if certain conditions are met.

The Mandiant Board also considered a number of uncertainties and risks and other potentially negative factors, including the following:

•

Regulatory Risks. The possibility that regulatory agencies may delay, object to or challenge the merger or may seek to impose terms and conditions on their approvals that are not acceptable to Parent. In this regard, the Mandiant Board noted that, although Parent is required to use its reasonable best efforts to secure all necessary regulatory approvals and may be required to pay a termination fee if those approvals are not obtained, Parent is not contractually obligated to agree to specific terms and conditions to secure those approvals.

•

No Stockholder Participation in Future Growth or Earnings. The nature of the merger as a cash transaction means that our stockholders will not participate in Mandiant’s future earnings or growth and will not benefit from any appreciation in value of the surviving corporation. The Mandiant

TABLE OF CONTENTS

Board considered the other potential alternative strategies available to Mandiant as an independent company, which, despite significant uncertainty, had the potential to result in a more successful and valuable company.

•

Restrictions on Mandiant’s Ability to Solicit Alternative Transactions. The restrictions in the merger agreement on Mandiant’s ability to solicit alternative acquisition proposals (subject to certain exceptions to allow the Mandiant Board to exercise its fiduciary duties and to accept a superior proposal, and then only upon the payment of a termination fee).

•

Risk Associated with Failure to Consummate the Merger. The possibility that the merger might not be consummated, and if it is not consummated, that: (1) Mandiant’s directors, senior management and other employees will have expended extensive time and effort and will have experienced significant distractions from their work on behalf of Mandiant during the pendency of the merger; (2) Mandiant will have incurred significant transaction and other costs; (3) Mandiant’s continuing business relationships with customers, business partners and employees may be adversely affected; (4) the trading price of our common stock could be adversely affected; (5) the termination fee payable by Parent to Mandiant will not be available in all instances in which the merger agreement is terminated and such termination fee may not be sufficient to compensate us for the damage suffered by our business as a result of the pendency of the merger or of the strategic initiatives forgone by Mandiant during this period; (6) the other contractual and legal remedies available to Mandiant in the event of the termination of the merger agreement may be insufficient, costly to pursue or both; and (7) the failure of the merger to be consummated could result in an adverse perception among our customers, potential customers, employees and investors about Mandiant’s prospects.

•

Impact of Interim Restrictions on Mandiant’s Business Pending the Completion of the Merger. The restrictions on the conduct of our business prior to the consummation of the merger, which may delay or prevent us from undertaking strategic initiatives before the completion of the merger that, absent the merger agreement, we might have pursued.

•

Effects of the Merger Announcement. The effects of the public announcement of the merger, including the: (1) effects on our employees, customers, operating results and stock price; (2) impact on our ability to attract and retain key management, sales and marketing, and technical personnel; and (3) potential for litigation in connection with the merger.

•

Termination Fee Payable by Mandiant. The requirement that we pay Parent a termination fee of $197,000,000 under certain circumstances following termination of the merger agreement, including if the Mandiant Board terminates the merger agreement to accept a superior proposal. The Mandiant Board considered the potentially discouraging impact that this termination fee could have on a third party’s interest in making an alternative acquisition proposal to acquire Mandiant.

•

Taxable Consideration. The receipt of cash in exchange for shares of our common stock in the merger will be a taxable transaction for U.S. federal income tax purposes for many Mandiant stockholders.

•

Interests of Mandiant’s Directors and Executive Officers. The interests that our directors and executive officers may have in the merger, which may be different from, or in addition to, those of our other stockholders.

This discussion is not meant to be exhaustive. Rather, it summarizes the material reasons and factors evaluated by the Mandiant Board in its consideration of the merger. After considering these and other factors, the Mandiant Board concluded that the potential benefits of entering into the merger agreement outweighed the uncertainties and risks. In light of the variety of factors considered by the Mandiant Board and the complexity of these factors, the Mandiant Board did not find it practicable to, and did not, quantify or otherwise assign relative weights to the foregoing factors in reaching its determination and recommendations. Moreover, each member of the Mandiant Board applied his or her own personal business judgment to the process and may have assigned different relative weights to the different factors. The Mandiant Board approved the merger agreement and the merger, and recommended that our stockholders adopt the merger agreement, based upon the totality of the information presented to, and considered by, the Mandiant Board.

TABLE OF CONTENTS

Opinion of Goldman Sachs & Co. LLC

Goldman Sachs rendered to the Mandiant Board its oral opinion, subsequently confirmed in its written opinion dated March 7, 2022, to the effect that, as of the date of the written opinion and based upon and subject to the factors and assumptions set forth therein, the $23.00 in cash per share of our common stock to be paid to the holders (other than Parent and its affiliates) of shares of our common stock, pursuant to the merger agreement, was fair from a financial point of view to the holders of such shares.

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

•

the merger agreement;

•

annual reports to stockholders and Annual Reports on Form 10-K of Mandiant (formerly FireEye, Inc.) for the five fiscal years ended December 31, 2021;

•

certain interim reports to stockholders and Quarterly Reports on Form 10-Q of Mandiant;

•

certain other communications from Mandiant to its stockholders;

•

certain publicly available research analyst reports for Mandiant; and

•

certain internal financial analyses and forecasts for Mandiant (including a schedule of expected net operating loss carryforwards by Mandiant), prepared by Mandiant management, as approved for Goldman Sachs’ use by Mandiant, which are referred to as “Forecasts.”

Goldman Sachs also held discussions with members of the senior management of Mandiant regarding their assessment of the strategic rationale for, and the potential benefits of, the merger and the past and current business operations, financial condition, and future prospects of Mandiant; reviewed the reported price and trading activity for our common stock; compared certain financial and stock market information for Mandiant with similar financial and stock market information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the software industry and in other industries; and performed such other studies and analyses, and considered such other factors, as it deemed appropriate.

For purposes of rendering its opinion, Goldman Sachs, with the Mandiant Board’s consent, relied upon and assumed the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by, it, without assuming any responsibility for independent verification thereof. In that regard, Goldman Sachs assumed with the Mandiant Board’s consent that the Forecasts have been reasonably prepared on a basis reflecting the best then available estimates and judgments of the management of Mandiant. Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of Mandiant or any of its subsidiaries and Goldman Sachs was not furnished with any such evaluation or appraisal. Goldman Sachs assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the merger would be obtained without any adverse effect on Mandiant or on the expected benefits of the merger in any way meaningful to Goldman Sachs’ analysis. Goldman Sachs has also assumed that the merger would be consummated on the terms set forth in the merger agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to its analysis.

Goldman Sachs’ opinion did not address the underlying business decision of Mandiant to engage in the merger or the relative merits of the merger as compared to any strategic alternatives that may be available

TABLE OF CONTENTS

to Mandiant; nor did it address any legal, regulatory, tax or accounting matters. Goldman Sachs’ opinion addresses only the fairness from a financial point of view, as of the date of its opinion, to the holders (other than Parent and its affiliates) of shares of our common stock, of the $23.00 in cash per share of our common stock to be paid to such holders pursuant to the merger agreement. Goldman Sachs’ opinion does not express any view on, and does not address, any other term or aspect of the merger agreement or the merger or any term or aspect of any other agreement or instrument contemplated by the merger agreement or entered into or amended in connection with the merger, including the fairness of the merger to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of Mandiant; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of Mandiant, or class of such persons in connection with the merger, whether relative to the $23.00 in cash per share to be paid to the holders (other than Parent and its affiliates) of shares of our common stock pursuant to the merger agreement or otherwise. Goldman Sachs did not express any opinion as to the prices at which shares of our common stock will trade at any time, as to the potential effects of volatility in the credit, financial and stock markets on Mandiant or Parent or the merger, or as to the impact of the merger on the solvency or viability of Mandiant or Parent or the ability of Mandiant or Parent to pay their respective obligations when they come due. Goldman Sachs’ opinion was necessarily based on economic, monetary market and other conditions, as in effect on, and the information made available to it as of the date of its written opinion and Goldman Sachs assumed no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after the date of its written opinion. Goldman Sachs’ advisory services and its opinion were provided for the information and assistance of the Mandiant Board in connection with its consideration of the merger and such opinion does not constitute a recommendation as to how any holder of shares of our common stock should vote with respect to the merger or any other matter. Goldman Sachs’ opinion was approved by a fairness committee of Goldman Sachs.

Summary of Financial Analyses

The following is a summary of the material financial analyses delivered by Goldman Sachs to the Mandiant Board in connection with rendering the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Some of the summaries of the financial analyses include 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 Goldman Sachs’ financial analyses. 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 March 4, 2022, and is not necessarily indicative of current market conditions.

Implied Premia Analysis

Goldman Sachs calculated and compared certain implied premia described below based on the $23.00 in cash per share of our common stock to be paid to the holders (other than Parent and its affiliates) of shares of our common stock pursuant to the merger agreement.

Goldman Sachs calculated the implied premia represented by the $23.00 in cash per share of our common stock relative to:

•

$15.06, the undisturbed closing price for our common stock on February 7, 2022, the last trading day prior to media reports regarding a potential sale of Mandiant (the “Undisturbed Share Price”);

•

the volume weighted average price (which we refer to as “VWAP”) of our common stock over the 5-trading-day time period ended February 7, 2022 (which we refer to as “5-day Undisturbed VWAP”);

•

the VWAP of our common stock over the 10-trading-day time period ended February 7, 2022 (“10-day Undisturbed VWAP”); and

•

$19.38, the closing price for our common stock on March 4, 2022, the last trading day prior to further media reports regarding the merger (which we refer to as the “Current Share Price”).

TABLE OF CONTENTS

The results of these calculations and comparisons were as follows:

Common Stock Reference Price	Implied Premium Represented by $23.00 in Cash per Share of our Common Stock
Undisturbed Share Price of $15.06		53%
5-day Undisturbed VWAP		54%
10-day Undisturbed VWAP		57%
Current Share Price of $19.38		19%

Illustrative Discounted Cash Flow Analysis

Using the Forecasts, Goldman Sachs performed an illustrative discounted cash flow analysis on Mandiant to derive a range of illustrative present values per share of Company Stock. Using discount rates ranging from 9.25 percent to 11.25 percent, reflecting estimates of Mandiant’s weighted average cost of capital, and the mid-year convention, Goldman Sachs discounted to present value as of December 31, 2021 (1) the estimates of unlevered free cash flow (“UFCF”) for Mandiant for the years 2022 through 2035 as reflected in the Forecasts; and (2) a range of illustrative terminal values for Mandiant, which were calculated by applying perpetuity growth rates ranging from 2.0% to 4.0%, to a terminal year estimate of the free cash flow to be generated by Mandiant, as provided by management of Mandiant and approved for Goldman Sachs’ use by management of Mandiant (which analysis implied exit terminal year NTM EBITDA multiples ranging from 6.9x to 12.0x). Goldman Sachs derived such discount rates by application of the Capital Asset Pricing Model, which requires certain company-specific inputs, including the company’s target capital structure weightings, the cost of long-term debt, after-tax yield on permanent excess cash, if any, future applicable marginal cash tax rate and a beta for the company, as well as certain financial metrics for the United States financial markets generally. The range of perpetuity growth rates was estimated by Goldman Sachs utilizing its professional judgment and experience, taking into account the Forecasts and market expectations regarding long-term real growth of gross domestic product and inflation.

Goldman Sachs derived a range of illustrative enterprise values for Mandiant by adding the range of present values it derived as described above and the net present value of the net operating losses as reflected in the Forecasts, as provided by the management of Mandiant and approved for Goldman Sachs’ use by the management of Mandiant. Goldman Sachs then subtracted from the range of illustrative enterprise values it derived for Mandiant, the net debt (including the amount of the liquidation preference of Mandiant’s convertible preferred stock) of Mandiant as of December 31, 2021, as provided by the management of Mandiant and approved for Goldman Sachs’ use by the management of Mandiant, to derive a range of illustrative equity values for Mandiant. Goldman Sachs then divided the range of illustrative equity values it derived by the number of fully diluted outstanding shares of Mandiant (which includes the number of shares of common stock, if any, underlying Mandiant’s convertible preferred stock attributable to the portion of the value of the convertible preferred stock in excess of the liquidation preference), as provided by the management of Mandiant and approved for Goldman Sachs’ use by management of Mandiant, using the treasury stock method, to derive a range of illustrative present values per share of our common stock ranging from $13.45 to $21.74.

Illustrative Present Value of Future Share Price Analysis

Goldman Sachs performed an illustrative analysis of the implied present value of an illustrative future value per share of our common stock, which is designed to provide an indication of the present value of a theoretical future value of a company’s equity as a function of such company’s financial multiples. For this analysis, Goldman Sachs used the Forecasts for each of the fiscal years 2022 through 2025. Goldman Sachs first calculated the implied enterprise values per share of our common stock as of December 31 for each of the fiscal years 2022 to 2024, by applying multiples of enterprise value to NTM revenue (which is referred to as “EV/NTM revenue,”) of 6.0x to 8.0x to estimates of Mandiant’s revenue for each of the fiscal years 2023 to 2025. These illustrative EV/NTM revenue multiple estimates were derived by Goldman Sachs utilizing its professional judgment and experience, taking into account current and historical EV/NTM revenue multiples for Mandiant and current and historical EV/NTM revenue multiples for certain publicly traded companies, as described below in the section captioned “— Selected Public Company Comparables Analysis.”

TABLE OF CONTENTS

Goldman Sachs then subtracted the amount of Mandiant’s forecasted net debt (including the amount of the liquidation preference of Mandiant’s convertible preferred stock) as of December 31 for each of the fiscal years 2022 to 2024, each as provided by the management of Mandiant and approved for Goldman Sachs’ use by the management of Mandiant, to derive a range of illustrative equity values for Mandiant as of December 31 for each of the fiscal years 2022 to 2024. Goldman Sachs then divided the results by the number of projected year-end fully diluted shares of our common stock (which includes the number of shares of common stock, if any, underlying Mandiant’s convertible preferred stock attributable to the portion of the value of the convertible preferred stock in excess of the liquidation preference) for each of the fiscal years 2022 to 2024, as provided by the management of Mandiant and approved for Goldman Sachs’ use by the management of Mandiant, to derive a range of implied future share prices. Goldman Sachs then discounted the December 31, 2022 to December 31, 2024 implied future share prices back to December 31, 2021 using an illustrative discount rate of 9.5 percent to derive implied present values of future share prices as of December 31, 2021. The illustrative discount rate of 9.5 percent reflected an estimate of Mandiant’s cost of equity. Goldman Sachs derived such discount rate by application of the Capital Asset Pricing Model, which requires certain company-specific inputs, including a beta for the company, as well as certain financial metrics for the United States financial markets generally. This analysis resulted in a range of implied present values of $17.47 to $26.25 per share of our common stock.

Precedent Transaction Multiples

Goldman Sachs analyzed certain publicly available information relating to the following selected transactions in the security and infrastructure software and high growth IT services industries since 2013. For each of the selected transactions where information was publicly available, Goldman Sachs calculated and compared the implied EV/NTM revenue of the applicable target company based on the total consideration paid in the transaction as a multiple of the target company’s NTM revenue based on Institutional Brokers’ Estimate System estimates (which are referred to as “IBES estimates”) at the time each such selected transaction was announced. While none of the companies that participated in the selected transactions are directly comparable to Mandiant, the companies that participated in the selected transactions are companies with operations that, for the purposes of analysis, may be considered similar to certain of Mandiant’s results, industry size and product profile.

TABLE OF CONTENTS

The following table presents the results of this analysis:

Security and Infrastructure Software Selected Precedent Transactions
Announcement Date	Target	Acquiror	EV/NTM Revenue
Dec 2021	Mimecast Ltd.	Permira I.P Limited	8.8 x
Nov 2021	McAfee Corp.	Advent International Corp. and Permira Advisers LLC	6.9 x
Aug 2021	Avast PLC — Stock Election	NortonLifeLock Inc.	8.8 x
Aug 2021	Avast PLC — Cash Election	NortonLifeLock Inc.	9.7 x
Apr 2021	Proofpoint Inc.	Thoma Bravo	9.5 x
Mar 2021	Talend S.A.	Thoma Bravo	7 x
Oct 2019	Sophos Ltd.	Thoma Bravo	4.9 x
Aug 2019	Carbon Black, Inc.	Vmware, Inc.	7.7 x
Nov 2018	Apptio Inc.	Vista Equity Partners Management LLC	6.9 x
Oct 2018	Imperva Inc.	Thoma Bravo	4.5 x
Sept 2016	Apigee Corp.	Google LLC	4.5 x
Oct 2015	SolarWinds, Inc.	Silver Lake Partners and Thoma Bravo	7.8 x
Jul 2013	Sourcefire Inc.	Cisco Systems, Inc.	7.9 x
Median			7.3 x
Mean			7.7 x

High Growth IT Services Selected Precedent Transactions
Announcement Date	Target	Acquiror	EV/NTM Revenue
Mar 2021	GlobalLogic Worldwide Holdings	Hitachi, Ltd.	7.9 x
Sep 2020	Virtusa Corporation	Baring Private Equity Asia	1.3 x
Aug 2020	Aareon AG	Advent International	3.7 x
Jun 2019	Altran Technologies SA	Capgemini SE	1.5 x
Jan 2019	Luxoft Holding, Inc.	DXC Technology	2 x
Dec 2017	Gemalto	Thales S.A.	1.8 x
Aug 2016	Rackspace Technology, Inc.	Apollo Global Management Inc.	2 x
Apr 2015	IGATE	Capgemini SE	3.1 x
Median			2.9 x
Mean			2.0 x

Based on the results of the foregoing calculations and Goldman Sachs’ analyses of the various transactions and its professional judgment and experience, Goldman Sachs selected a reference range of EV/NTM revenue multiples of 6.0x to 9.0x and applied such range to Mandiant’s NTM revenue as of December 31, 2021, as provided by the management of Mandiant, to derive a range of implied enterprise values for Mandiant. Goldman Sachs then subtracted from the range of implied enterprise values the amount of Mandiant’s net debt (including the amount of the liquidation preference of Mandiant’s convertible preferred stock) as of December 31, 2021, as provided by the management Mandiant and approved for Goldman Sachs’ use by the management of Mandiant, to derive a range of illustrative equity values for Mandiant. Goldman Sachs divided the results by the number of fully diluted outstanding shares of our common stock (which includes the number of shares of common stock, if any, underlying Mandiant’s convertible preferred stock attributable to the portion of the value of the convertible preferred stock in excess of the liquidation preference), as provided by the management of Mandiant and approved for Goldman Sachs’ use by the management of Mandiant, using the treasury stock method, to derive a range of implied equity values per share of our common stock of $16.08 to $22.30.

TABLE OF CONTENTS

Premia Paid Analysis

Goldman Sachs reviewed and analyzed, using publicly available information, the acquisition premia for all-cash acquisition transactions announced from 2017 through February 14, 2022, involving a public company based in the United States as the target where the disclosed enterprise value for the transaction was between $1 billion and $10 billion. For the entire period, using publicly available information, Goldman Sachs calculated the median, 25th percentile and 75th percentile premia of the price paid in the transactions relative to the target’s last undisturbed closing stock price prior to announcement of the transaction. This analysis indicated a median premium of 29 percent across the period. This analysis also indicated a 25th percentile premium of 17 percent and a 75th percentile premium of 49 percent across the period. Using this analysis, Goldman Sachs applied a reference range of illustrative premia of 17% to 49 percent to the unaffected closing price per share of our common stock of $15.06 as of February 7, 2022 and calculated a range of implied equity values per share of our common stock of $17.62 to $22.44.

Selected Public Company Comparables Analysis

Goldman Sachs reviewed and compared certain financial and stock market information for the following publicly traded corporations in the security and infrastructure software industry, which are collectively referred to as the “security comparable companies”:

•

Cyberark Software Ltd.;

•

ForgeRock Inc.;

•

Rapid7 Inc.;

•

Sailpoint Technologies Holdings Inc.;

•

Sumo Logic Inc.;

•

Tenable Holdings Inc.; and

•

Varonis Systems Inc.

Goldman Sachs also reviewed and compared certain financial and stock market information for the following publicly traded corporations in the high growth IT services industry, which are collectively referred to as the “services comparable companies”:

•

Endava PLC — ADR;

•

EPAM Systems Inc.;

•

Globant SA; and

•

Perficient, Inc.

The security comparable companies and the services comparable companies are collectively referred to as the “comparable companies.” Although none of the comparable companies is directly comparable to Mandiant, the companies included were chosen because they are publicly traded companies in the security and infrastructure software industry and high growth IT services industry, respectively, with operations that for purposes of analysis may be considered similar to certain operations of Mandiant.

Goldman Sachs calculated and compared the enterprise value as of March 4, 2022 as a multiple of revenue for the comparable companies for calendar years 2022 and 2023, based on financial and trading data as of March 4, 2022, information Goldman Sachs obtained from Thomson Reuters and CapIQ, publicly available historical and market data and IBES estimates, in order to determine an appropriate EV/NTM revenue multiple range for Goldman Sachs’ illustrative present value of future share price analysis.

TABLE OF CONTENTS

The results of this analysis are summarized as follows:

Security Comparable Company

CY 22 EV/
Revenue

CY 23 EV/
Revenue

Cyberark Software Ltd.

9.9x

8.1x

ForgeRock Inc.

5.8x

4.6x

Rapid7 Inc.

10.3x

8.4x

Sailpoint Technologies Holdings Inc.

8.6x

7.1x

Sumo Logic Inc.

3.9x

3.3x

Tenable Holdings Inc.

9.9x

8.2x

Varonis Systems Inc.

8.7x

7.2x

Median

8.7x

7.2x

Services Comparable Company

CY 22 EV/
Revenue

CY 23 EV/
Revenue

Endava PLC – ADR

6.0x

4.8x

EPAM Systems Inc.

2.0x

1.6x

Globant SA

5.4x

4.3x

Perficient, Inc.

4.3x

3.7x

Median

4.9x

4.0x

General

The preparation of a fairness opinion is a complex process and is not necessarily 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 Goldman Sachs’ opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs 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 Mandiant or the contemplated merger.

Goldman Sachs prepared these analyses for purposes of Goldman Sachs’ providing its opinion to the Mandiant Board as to the fairness from a financial point of view of the $23.00 price per share to be paid to the holders (other than Parent and its affiliates) of shares of our common stock, pursuant to the merger agreement. 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 uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of Mandiant, Parent, Goldman Sachs 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 Mandiant and Parent and was approved by the Mandiant Board. Goldman Sachs provided advice to Mandiant during these negotiations. Goldman Sachs did not, however, recommend any specific amount of consideration to Mandiant or the Mandiant Board or that any specific amount of consideration constituted the only appropriate consideration for the merger.

As described above, Goldman Sachs’ opinion to the Mandiant Board was one of many factors taken into consideration by the Mandiant Board in making its determination to approve the merger agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with the fairness opinion and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex C.

TABLE OF CONTENTS

Goldman Sachs and its affiliates are engaged in advisory, underwriting and financing, principal investing, sales and trading, research, investment management and other financial and non-financial activities and services for various persons and entities. Goldman Sachs and its affiliates and employees, and funds or other entities they manage or in which they invest or have other economic interests or with which they co-invest, may at any time purchase, sell, hold or vote long or short positions and investments in securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments of Mandiant, Parent, any of their respective affiliates and third parties, including Alphabet Inc. (“Alphabet”), an affiliate of Parent, and any of its affiliates and, as applicable, portfolio companies, or any currency or commodity that may be involved in the transaction contemplated by the merger agreement. Goldman Sachs acted as financial advisor to Mandiant in connection with, and participated in certain of the negotiations leading to, the transaction contemplated by the agreement. Goldman Sachs has provided certain financial advisory and/or underwriting services to Mandiant and its affiliates from time to time for which the Investment Banking Division of Goldman Sachs has received, and may receive, compensation, including having acted as Mandiant’s financial advisor in connection with the sale of its FireEye Products business in October 2021. During the two year period ended March 7, 2022, Goldman Sachs has recognized compensation for financial advisory and/or underwriting services provided by its Investment Banking Division to Mandiant and/or its affiliates of approximately $20 million. Goldman Sachs also has provided certain financial advisory and/or underwriting services to Parent, Alphabet and/or their respective affiliates and portfolio companies from time to time for which the Investment Banking Division of Goldman Sachs has received, and may receive, compensation, including having acted as financial advisor to Ionic Security Inc., a former portfolio company of Google Ventures, an affiliate of Alphabet, with respect to its sale in April 2021; and as financial advisor to Kobalt Music Group Limited, a former portfolio company of Google Ventures, with respect to its sale in May 2021. During the two year period ended March 7, 2022, Goldman Sachs has recognized compensation for financial advisory and/or underwriting services provided by its Investment Banking Division to Parent, Alphabet and/or their respective affiliates and portfolio companies of approximately $5 million. Goldman Sachs may also in the future provide financial advisory and/or underwriting services to Mandiant, Parent, Alphabet and their respective affiliates for which the Investment Banking Division of Goldman Sachs may receive compensation. Affiliates of Goldman Sachs also may have co-invested with Parent, Alphabet and their respective affiliates from time to time and may do so in the future.

Goldman Sachs also acted as bookrunner with respect to the offering by Mandiant of 0.875% Convertible Senior Notes due 2024 in an aggregate principal amount of $600 million, which are referred to as the “Mandiant convertible notes” and, concurrent with the issuance of the Mandiant convertible notes, Mandiant entered into capped call transactions with respect to the shares of common stock underlying the Mandiant convertible notes, which are collectively referred to as the “capped call transactions,” with Goldman Sachs (with respect to 30% of the shares of common stock underlying the Mandiant convertible notes) and other counterparties each acting as principal for its own account, consisting of the purchase by Mandiant of capped call options with respect to collectively approximately 25,900,020 shares of our common stock, the aggregate number of shares of our common stock underlying the Mandiant convertible notes (at the initial conversion rate of 43.1667 shares of our common stock per $1,000 in principal amount of Mandiant convertible notes). The Mandiant convertible notes had an initial strike price equal to $23.17 per share of our common stock, subject to an initial cap price of $34.32 per share. As of March 28, 2022, 100% of the capped call transactions remain outstanding, with a strike price of approximately $23.17 and a cap price of $34.32.

The capped call transactions were intended to offset a portion of the potential dilutive effect on Mandiant stockholders of the conversion of the Mandiant convertible notes and/or any potential cash payment in excess of the principal amount of the Mandiant convertible notes that Mandiant may make in connection with a cash settlement of the Mandiant convertible notes, in each case, up to the cap price. The capped call transactions, upon the exercise thereof, generally require the capped call counterparties to deliver to Mandiant upon expiration of the call options, a number of shares of our common stock (and/or in certain circumstances, at Mandiant’s election, cash) determined based on the excess, if any, of the lower of the cap price and the price of the shares of our common stock at that time (determined over a period specified in the capped call transactions) over the strike price per share of our common stock.

TABLE OF CONTENTS

The capped call transactions may be adjusted, exercised, cancelled and/or terminated in accordance with their terms in connection with certain events. In particular, under the terms of the capped call transactions, Goldman Sachs and the other counterparties, each acting separately as calculation agent under the capped call transactions to which it is a party, are entitled in certain circumstances to make adjustments on more than one occasion to the terms of such capped call transactions to reflect the economic effect of the announcement of such events (including the merger) on the embedded call options. In addition, each of Goldman Sachs and the other counterparties may, acting separately as the calculation agent, determining party or otherwise as principal under the capped call transactions to which it is a party, determine such adjustments in respect of such capped call transactions in accordance with their terms, including on or following consummation or abandonment of such events. All actions or exercises of judgment by Goldman Sachs, in its capacity as calculation agent, pursuant to the terms of the capped call transactions to which it is a party must be performed in good faith and a commercially reasonable manner.

As a result of the capped call transactions, the capped call counterparties are expected to have market exposure to the price of the shares of our common stock. It is the ordinary practice of the capped call counterparties to engage in hedging activities to limit their respective market exposure to the price of the stock underlying privately negotiated equity derivative transactions with issuers of such stock, such as the capped call transactions. In connection with the capped call transactions to which it is a party, Goldman Sachs (and its affiliates) have engaged, and will continue to engage, in accordance with applicable law in hedging and other market transactions (which may include the entering into or unwinding of various derivative transactions with respect to our common stock) that are generally intended to substantially neutralize Goldman Sachs’ exposure as a result of the capped call transactions to which it is a party to changes in the price of our common stock. Such hedging activity is at Goldman Sachs’ own risk and may result in a gain or loss to Goldman Sachs that may be greater than or less than the initial expected contractual benefit to Goldman Sachs under the capped call transactions to which it is a party. The amount of any such gain or loss will not be known until the applicable capped call transactions have been exercised, expired or terminated in accordance with their terms and Goldman Sachs shall have completed all of its hedge unwind activities. In accordance with industry practice, Goldman Sachs maintains customary institutional information barriers reasonably designed to prevent the unauthorized disclosure of confidential information by personnel in its Investment Banking Division to the personnel in its Securities Division who are undertaking hedging and other market transactions with respect to Goldman Sachs’ capped call transactions. To mitigate the exposure from the capped call transactions, as of March 28, 2022, Goldman Sachs held a net long economic position of approximately 4.4 million shares of our common stock.

Goldman Sachs provided to management of Mandiant, for the information of the Mandiant Board, materials that summarized, based on theoretical models, the potential effects of the announcement and of the consummation of an acquisition of Mandiant on the capped call transactions. The materials included preliminary illustrative analyses by Goldman Sachs’ Investment Banking Division for a range of stated assumptions regarding takeout prices for shares of our common stock and volatilities, as well as based on other reasonable assumptions, in the event of an acquisition of Mandiant for greater than 10 percent cash consideration. The materials calculated over a range of potential takeout prices for the shares of our common stock ranging from $16.00 per share to $26.00 per share and volatilities (from 25 percent to 35 percent) and for an announcement date of March 10, 2022, and other stated assumptions that upon the full unwind of the capped call transactions, Goldman Sachs might realize, after taking into account any estimated hedging gains or losses, a net gain or loss ranging from a net loss of approximately $1.8 million to a net gain of approximately $4.8 million. In accordance with industry practice, Goldman Sachs maintains customary institutional information barriers reasonably designed to prevent the unauthorized disclosure of confidential information by personnel in its Investment Banking Division to the personnel in its Securities Division who are undertaking hedging and other market transactions with respect to Goldman Sachs’ capped call transactions. In connection with the preparation of presentations to senior management of Mandiant and the Mandiant Board, personnel in Goldman Sachs’ Investment Banking Division, including the representatives of Goldman Sachs who have advised Mandiant in connection with the merger, from time to time, have received or may receive input from personnel in Goldman Sachs’ Securities Division into how to model, or reports of historical measures or estimates of, Goldman Sachs’ and/or Goldman Sachs’ Investment Banking Division’s profit and/or loss over certain measurement periods related to the capped call transactions.

TABLE OF CONTENTS

The indentures governing the Mandiant convertible notes and the confirmations containing the terms of the capped call transactions were included as exhibits to Mandiant’s Current Report on Form 8-K filed with the SEC on May 25, 2018, which contains additional disclosure regarding the Mandiant convertible notes and a description of the capped call transactions. All references in this section to share counts, conversion prices, cap prices and strike prices are subject to adjustment from time to time in accordance with the terms of the confirmations relating to the capped call transactions.

The Mandiant Board selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the merger. Pursuant to a letter agreement dated September 16, 2019, Mandiant engaged Goldman Sachs to act as its financial advisor in connection with the contemplated merger. The engagement letter between Mandiant and Goldman Sachs provides for a transaction fee that is estimated, based on the information available as of the date of announcement and assuming that certain Mandiant convertible notes are redeemed prior to the close of the transaction per guidance from Mandiant management, at approximately $[•] million, all of which is contingent upon consummation of the merger. The transaction fee is subject to upward adjustment by approximately $[•] million in the event that none of the Mandiant convertible notes are redeemed prior to the close of the transaction. In addition, Mandiant has agreed to reimburse Goldman Sachs for certain of its expenses, including attorneys’ fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities, including certain liabilities under the federal securities laws.

Projected Financial Information

Other than in connection with its regular earnings press releases and related investor materials, we do not, as a matter of course, make public projections as to our future financial performance, due to, among other reasons, the uncertainty, unpredictability and subjectivity of the underlying assumptions and estimates. However, Mandiant management regularly prepares projections as to our future financial performance for internal use.

In connection with our strategic planning process and evaluation of strategic alternatives, Mandiant management prepared and provided to the Mandiant Board various unaudited forward-looking financial information for fiscal years 2022 through 2035. This forward-looking information is collectively referred to as the “Projected Financial Information.” The Projected Financial Information was approved by Mandiant for Goldman Sachs’ use for purposes of performing its financial analyses in connection with rendering its fairness opinion to the Mandiant Board (as described in more detail in the section of this proxy statement captioned “— Opinion of Goldman Sachs & Co. LLC”). A summary of the Projected Financial Information is set forth below.

The Projected Financial Information was developed by Mandiant management without giving effect to the merger or to any changes to Mandiant’s operations or strategy that may be implemented after the consummation of the merger. The Projected Financial Information also does not consider the effect of any failure of the merger to be completed; it should not be viewed as accurate or continuing in that context.

The Projected Financial Information was not prepared with a view toward public disclosure or complying with accounting principles generally accepted in the United States (which we refer to as “GAAP”). In addition, the Projected Financial Information was not prepared with a view toward complying with the guidelines established by the SEC or the American Institute of Certified Public Accountants with respect to prospective financial information. Neither our independent registered public accounting firm nor any other independent accountants have (1) compiled, reviewed, audited, examined or performed any procedures with respect to the Projected Financial Information; (2) expressed any opinion or any other form of assurance on such information or the achievability of the Projected Financial Information; or (3) assumed any responsibility for the Projected Financial Information. Our independent registered public accounting firm disclaims any association with the Projected Financial Information.

The Projected Financial Information was prepared by, and is the responsibility of, Mandiant management. In the opinion of Mandiant management, the Projected Financial Information (1) was prepared on a reasonable basis; (2) reflected the best estimates and judgments then available (taking into account the relevant information available to Mandiant management at that time); and (3) presented, to Mandiant management’s knowledge, our expected future financial performance within the parameters and

TABLE OF CONTENTS

under the assumptions specified in preparing the Projected Financial Information. Because the Projected Financial Information reflects estimates and judgments, it is susceptible to sensitivities and assumptions, as well as multiple interpretations based on actual experience and business developments. The Projected Financial Information also covers multiple years, and such information by its nature becomes less predictive with each succeeding year. The Projected Financial Information is not, and should not be considered to be, a guarantee of future operating results. Further, the Projected Financial Information is not fact, is subjective in many respects, and should not be relied upon as being necessarily indicative of Mandiant’s future results.

Although the Projected Financial Information is presented with numerical specificity, it reflects numerous assumptions and estimates as to future events made by Mandiant management that Mandiant management considered reasonable. Our ability to achieve the financial results contemplated by the Projected Financial Information will be affected by our ability to achieve our strategic goals, objectives and targets over the applicable periods. The Projected Financial Information reflects assumptions as to certain business decisions that are subject to change. Important factors that may affect actual results and cause the Projected Financial Information not to be achieved include, among others, (1) general economic conditions (including the impact of COVID-19 and COVID-19 measures); (2) the accuracy of certain accounting assumptions; (3) changes in actual or projected cash flows; (4) competitive pressures; and (5) changes in tax laws. Additional factors that may impact us or our business can be found in the various risk factors included in our periodic filings with the SEC. All of these factors are difficult to predict, and many of them are outside of our control. As a result, there can be no assurance that the Projected Financial Information will be realized, and actual results may be materially better or worse than those contained in the Projected Financial Information. The Projected Financial Information may differ from publicized analyst estimates and forecasts and does not consider any events or circumstances after the date that it was prepared, including the announcement of the entry into the merger agreement. You should evaluate the Projected Financial Information, if at all, in conjunction with our historical financial statements and other information regarding Mandiant contained in our public filings with the SEC. Except to the extent required by applicable federal securities laws, we do not intend to update or otherwise revise the Projected Financial Information to reflect circumstances existing after the date that such information was prepared or to reflect the occurrence of future events, even if any or all of the assumptions underlying the Projected Financial Information are shown to be in error or no longer appropriate.

Certain of the financial measures included in the Projected Financial Information are “non-GAAP financial measures.” These are financial performance measures that are not calculated in accordance with GAAP. These non-GAAP financial measures should not be viewed as a substitute for GAAP financial measures, and may be different from non-GAAP financial measures used by other companies. Furthermore, there are limitations inherent in non-GAAP financial measures because they exclude charges and credits that are required to be included in a GAAP presentation. Accordingly, these non-GAAP financial measures should be considered together with, and not as an alternative to, financial measures prepared in accordance with GAAP.

Financial measures included in forecasts provided to a financial advisor and a board of directors in connection with a business combination transaction, such as the Projected Financial Information, are excluded from the definition of “non-GAAP financial measures” under applicable SEC rules and regulations. As a result, the Projected Financial Information is not subject to SEC rules regarding disclosures of non-GAAP financial measures, which would otherwise require a reconciliation of a non-GAAP financial measure to a GAAP financial measure. Reconciliations of non-GAAP financial measures were not provided to or relied upon by the Mandiant Board or Goldman Sachs. Accordingly, no reconciliation of the financial measures included in the Projected Financial Information is provided in this proxy statement.

The Projected Financial Information constitutes forward-looking statements. For information on factors that may cause Mandiant’s future results to materially vary, see the section of this proxy statement captioned “— Forward Looking Statements”. By including the Projected Financial Information in this proxy statement, neither we nor any of our advisors or other representatives has made or makes any representation to any person regarding our ultimate performance as compared to the information contained in the Projected Financial Information. The inclusion of the Projected Financial Information should not be regarded as an indication that the Mandiant Board, Mandiant or any other recipient of the Projected Financial Information considered, or now considers, the Projected Financial Information to be predictive of

TABLE OF CONTENTS

actual future results. Further, the inclusion of the Projected Financial Information in this proxy statement does not constitute an admission or representation by Mandiant that the information presented is material. The Projected Financial Information is included in this proxy statement solely to give our stockholders access to the information that was made available to the Mandiant Board and Goldman Sachs for purposes of performing its financial analyses in connection with rendering its fairness opinion to the Mandiant Board (as described in more detail in the section of this proxy statement captioned “— Opinion of Goldman Sachs & Co. LLC”). The Projected Financial Information is not included in this proxy statement for the purpose of influencing any Mandiant stockholder to make any investment decision with respect to the merger, including whether or not to seek appraisal rights with respect to such stockholder’s shares.

Certain of the Projected Financial Information was also provided to Parent.

The following table summarizes the Projected Financial Information.

	Fiscal year ending December 31
(dollars in millions)	2022E			2023E			2024E			2025E			2026E			2027E			2028E			2029E			2030E			2031E			2032E			2033E			2034E			2035E
Revenue		$	575		$	759		$	949		$	1,178		$	1,425		$	1,674		$	1,906		$	2,099		$	2,229		$	2,361		$	2,494		$	2,627		$	2,757		$	2,885
Gross profit			362			515			673			867			1,057			1,251			1,432			1,583			1,689			1,796			1,904			2,011			2,117			2,221
Research and development			(140)			(155)			(164)			(178)			(181)			(184)			(191)			(210)			(223)			(236)			(249)			(263)			(276)			(289)
Sales and marketing			(222)			(272)			(321)			(383)			(451)			(514)			(568)			(607)			(624)			(661)			(698)			(735)			(772)			(808)
General and administrative			(66)			(78)			(80)			(89)			(109)			(129)			(148)			(165)			(176)			(187)			(197)			(207)			(218)			(228)
EBIT (excluding stock-based compensation expense)(1)			(65)			10			107			217			316			423			525			602			665			712			759			806			852			896
Normalized Depreciation			17			18			18			19			24			29			35			40			45			51			57			64			72			70
EBITDA (excluding stock-based compensation expense)(2)			(48)			28			125			235			340			452			560			642			710			763			816			870			923			967
Other income/expense			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)			(1)
Cash taxes(3)			(4)			(4)			(4)			(5)			(25)			(47)			(70)			(88)			(102)			(111)			(121)			(131)			(141)			(150)
Capital expenditures			(26)			(32)			(37)			(43)			(49)			(53)			(56)			(56)			(54)			(58)			(61)			(64)			(67)			(70)
Unlevered free cash flow(4)			(14)			82			168			268			344			431			507			558			595			635			676			716			756			786
Stock-based compensation expense			(167)			(176)			(195)			(211)			(214)			(218)			(210)			(200)			(200)			(200)			(200)			(200)			(200)			(200)
Unlevered free cash flow (including stock-based compensation treated as a cash expense)			(180)			(94)			(27)			57			130			213			297			358			395			435			476			516			556			586

(1)

EBIT is defined as Mandiant’s gross profit less research and development, sales and marketing, and general and administrative expense.

(2)

EBITDA is defined as Mandiant’s EBIT plus the dollar amount of depreciation and amortization.

(3)

Excludes tax shield from net operating loss utilization.

(4)

Unlevered free cash flow is defined as Mandiant’s EBITDA plus change in deferred revenue, less other income/expense, cash taxes, restructuring / one-time items, and capital expenditures.

Interests of Mandiant’s Directors and Executive Officers in the Merger

When considering the recommendation of the Mandiant Board that you vote to approve the proposal to adopt the merger agreement, you should be aware that our directors and executive officers may have interests in the merger that are different from, or in addition to, the interests of our stockholders. Additionally, concurrently with the execution of the merger agreement, our chief executive officer, Kevin Mandia, in his capacity as a stockholder of Mandiant, entered into a voting agreement with Parent and Mandiant. The voting agreement obligates Mr. Mandia to vote certain of his shares of our common stock in favor of the adoption of the merger agreement and against any competing transaction. For more information, please see the section of this proxy statement captioned “The Merger — The Voting Agreements.” In (1) evaluating and negotiating the merger agreement; (2) approving the merger agreement and the merger; and (3) recommending that the merger agreement be adopted by our stockholders, the Mandiant Board was aware of and considered these interests to the extent that they existed at the time, among other matters. These interests are more fully described below.

TABLE OF CONTENTS

Insurance and Indemnification of Directors and Executive Officers

Pursuant to the terms of the merger agreement, directors and officers of Mandiant will be entitled to certain ongoing indemnification and insurance coverage, including under directors’ and officers’ liability insurance policies. For more information, see the section of this proxy statement captioned “The Merger Agreement — Indemnification and Insurance.”

Treatment of Equity-Based Awards

Treatment of Mandiant Restricted Stock Units

As of March 18, 2022, there were outstanding awards of Mandiant restricted stock units (or portions thereof) that cover an aggregate of 19,947,463 shares of our common stock, of which Mandiant restricted stock units covering an aggregate of [•] shares of our common stock were held by our current non-employee directors and of which Mandiant restricted stock units covering an aggregate of [•] shares of our common stock were held by our current executive officers. As of the same date, there were outstanding Mandiant PSUs that cover an aggregate of 2,361,933 shares of our common stock (at maximum level of performance), of which Mandiant PSUs covering an aggregate of [•] shares of our common stock (at maximum level of performance) were held by our current executive officers and of which none were held by our current non-employee directors.

Each vested Mandiant restricted stock unit will accelerate vesting in full (to the extent not already vested) and be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such vested Mandiant restricted stock unit and (2) the total number of shares of our common stock then-subject to such vested Mandiant restricted stock unit. This amount (less any required withholding and other taxes) will be paid to the applicable holder promptly following the effective time of the merger.

Each unvested Mandiant restricted stock unit will be cancelled and converted into a right to receive an amount in cash, without interest, equal to the product of (1) the excess of the per share price over the exercise or purchase price per share, if any, of such unvested Mandiant restricted stock unit and (2) the total number of shares of our common stock then-subject to such unvested Mandiant restricted stock unit. Such cash amount will (1) vest and become payable (less any required withholding and other taxes) in accordance with the vesting schedule applicable to the corresponding unvested Mandiant restricted stock unit immediately prior to the effective time of the merger, subject to such holder’s continued service with Parent and its affiliates through the applicable vesting dates, and (2) be subject to the terms and conditions of the unvested payment plan.

All other Mandiant restricted stock units not described above that are outstanding immediately prior to the effective time of the merger will be canceled for no consideration.

Treatment of Mandiant Performance-Based Awards

Each completed Mandiant PSU will be canceled and converted into a right to receive an amount in cash, without interest, equal to the completed Mandiant PSU consideration with such completed Mandiant PSU consideration vesting in accordance with the service-based vesting schedule applicable to such completed Mandiant PSU immediately prior to the effective time of the merger and subject to the terms of the unvested payment plan.

Treatment of Mandiant Options

As of March 18, 2022, there were outstanding Mandiant options to purchase an aggregate of 1,575,395 shares of our common stock (with a weighted average exercise price of $7.4816), of which Mandiant options to purchase an aggregate of 0 shares of our common stock were held by our current non-employee

TABLE OF CONTENTS

directors and of which Mandiant options to purchase an aggregate of 0 shares of our common stock were held by our current executive officers.

Treatment of the ESPP

Prior to the effective time of the merger Mandiant will take all action necessary to cause any offering period or purchase period under the ESPP that is outstanding as of the date of the merger agreement to be terminated no later than ten business days prior to the date of the closing of the merger. We will also make any adjustments that may be necessary or advisable to reflect the shortened offering period or purchase period. Mandiant will cause the exercise (as of no later than ten business days prior to the closing date of the merger) of each outstanding purchase right pursuant to the ESPP. On such exercise date, Mandiant will apply the funds credited as of such date pursuant to the ESPP within each participant’s account to the purchase of whole shares of Mandiant common stock in accordance with the terms of the ESPP. Immediately prior to and effective as of the effective time of the merger Mandiant will terminate the ESPP. No further offering period or purchase period will commence pursuant to the ESPP on or after the date of the closing of the merger. The amount of the accumulated contributions of each participant under the ESPP will, to the extent not used to purchase shares of common stock, be refunded in cash to such participant as promptly as practicable following the effective time of the merger.

Equity Interests of Mandiant’s Directors and Executive Officers

The following table sets forth for each person who has been an executive officer, which consists of each individual referred to as a “named executive officer” for purposes of this proxy statement (as defined in the section of this proxy statement below captioned “— Interests of Mandiant’s Directors and Executive Officers in the Merger — Golden Parachute Compensation”), or a member of the Mandiant Board at any time since the beginning of Mandiant’s 2021 fiscal year, (1) the number of shares of our common stock directly held; and (2) the number of shares of our common stock subject to his or her Mandiant restricted stock units and Mandiant PSUs (at actual levels of achievement for any completed Mandiant PSUs and at maximum levels of achievement for any uncompleted Mandiant PSUs), in each case as of March 18, 2022, assuming the following and such additional assumptions set forth in the footnotes to the table:

•

the Mandiant restricted stock units and Mandiant PSUs that were outstanding as of March 18, 2022 represent the full extent of equity awards that Mandiant will have granted to each named executive officer and member of the Mandiant Board through June 30, 2022, the assumed closing date of the merger solely for purposes of this proxy statement, provided that such awards (or portions thereof) that are expected to vest or be paid in accordance with their terms prior to June 30, 2022 are treated as having vested or been paid in accordance with their terms and excluded from the Mandiant restricted stock unit amounts and included in the shares held directly amounts in the table;

•

as of March 18, 2022, none of our named executive officers or members of the Mandiant Board hold any Mandiant options; and

•

that the values of these shares of our common stock and equity-based awards are equal to the per share price of $23.00.

TABLE OF CONTENTS

	Shares Held Directly(1)				Mandiant Restricted Stock Units(2)				Mandiant PSUs(2)
Name	Number of Shares (#)		Value of Shares ($)		Number of Shares (#)		Value ($)		Number of Shares (#)		Value ($)		Total ($)
Kimberly Alexy		93,252		2,144,796		—		—		—		—		2,144,796
Sara C. Andrews		13,172		302,956		16,692		383,916		—		—		686,872
Ronald E.F. Codd		5,075(3)		116,725		—		—		—		—		116,725
Arthur W. Coviello, Jr.		14,292(4)		328,716		19,281		443,463		—		—		772,179
Adrian McDermott		39,759		914,457		—		—		—		—		914,457
Viral Patel		—		—		—		—		—		—		—
Enrique Salem		290,513		6,681,799		—		—		—		—		6,681,799
Robert Switz		78,334		1,801,682		—		—		—		—		1,801,682
Alexa King		191,579(5)		4,406,317		—		—		—		—		4,406,317
Peter Bailey		46,421(6)		1,067,683		114,922		2,643,206		163,000		3,749,000		7,459,889
Kevin Mandia		3,071,877(7)		70,653,171		312,157		7,179,611		315,999		7,267,977		85,100,759
William T. Robbins		99,357		2,285,211		168,720		3,880,560		193,000		4,439,000		10,604,771
Frank E. Verdecanna		416,194		9,572,462		140,439		3,230,097		149,249		3,432,727		16,235,286
John P. Watters		212,563(8)		4,888,949		192,188		4,420,324		225,000(9)		5,175,000		14,484,273

(1)

Represents (i) shares of our common stock directly held by the individual as of March 18, 2022 and (ii) shares of our common stock subject to Mandiant restricted stock units that are expected to vest and be paid in accordance with their terms after March 18, 2022 and prior to June 30, 2022, the assumed closing date of the merger. The number of shares shown does not include shares of our common stock that the named executive officers may purchase after the date of the merger agreement under the ESPP. For additional information regarding the treatment of our ESPP in the merger, see the section of this proxy statement captioned “— Interests of Mandiant’s Directors and Executive Officers in the Merger — Treatment of Equity-Based Awards.” For additional information regarding beneficial ownership of common stock, see the section of this proxy statement captioned “Security Ownership of Certain Beneficial Owners and Management.”

(2)

Represents outstanding Mandiant restricted stock units and Mandiant PSUs (at the maximum level of achievement) based on the assumptions above, but including an aggregate of 187,172 shares of our common stock subject to Mandiant restricted stock units granted to our named executive officers on March 26, 2022 that will be unvested as of June 30, 2022, the assumed closing date of the merger. The number of shares subject to Mandiant restricted stock units shown does not include Mandiant restricted stock units that may be granted in the future to members of the Mandiant Board pursuant to the Mandiant Outside Director Compensation Policy. The values shown with respect to the Mandiant restricted stock units and Mandiant PSUs are determined as the product of the per share price, multiplied by the total number of shares of our common stock subject to such Mandiant restricted stock units or Mandiant PSUs, as applicable. For additional information regarding the Mandiant restricted stock units and Mandiant PSUs held by our named executive officers, see the section of this proxy statement captioned “— Interests of Mandiant’s Directors and Executive Officers in the Merger — Golden Parachute Compensation.”

(3)

Does not include 136,625 shares held of record by the Codd Revocable Trust Dated March 6, 1998, for which Mr. Codd serves as a trustee.

(4)

Does not include 12,878 shares held of record by the Arthur W. Coviello Jr. Revocable Trust, for which Mr. Coviello serves as a trustee.

(5)

Represents shares of our common stock directly held by Ms. King as of November 1, 2021, the date on which she ceased to serve as our Executive Vice President, Corporate and Legal Affairs, General Counsel, and Secretary.

(6)

With respect to shares of our common stock, represents shares held by Mr. Bailey as of April 5, 2021, the date on which he ceased to serve as our Chief Operating Officer.

TABLE OF CONTENTS

(7)

Does not include (i) 340,691 shares of our common stock held of record by Kevin R. Mandia 2011 Irrevocable Trust Dated July 29, 2011 and (ii) 144,185 shares of our common stock held of record by Mr. Mandia’s wife. Mr. Mandia’s wife, as trustee, has shared voting and investment power with respect to the shares held of record by the Kevin R. Mandia 2011 Irrevocable Trust dated July 29, 2011. Mr. Mandia disclaims beneficial ownership of the shares held of record by the Kevin R. Mandia 2011 Irrevocable Trust dated July 29, 2011 and the shares held of record by Mr. Mandia’s wife.

(8)

Does not include (i) 35,000 shares of our common stock held of record by Dorset Investment Partners, Ltd., a family limited partnership of which Mr. Watters and his spouse are general partners and (ii) 20,000 shares of our common stock held by JPW Advisory, Inc., for which Mr. Watters serves as the sole officer and director. Mr. Watters disclaims beneficial ownership of all shares held by the family limited partnership, except to the extent of his pecuniary interest therein.

(9)

Does not include 300,000 shares of our common stock subject to Mandiant PSUs with a stock price performance that were granted to Mr. Watters on April 8, 2021 and will be terminated prior to the closing of the merger without vesting, in accordance with their terms, unless otherwise vested prior to the closing of the merger in accordance with their terms.

2013 Equity Incentive Plan

We have granted certain Mandiant restricted stock units, and Mandiant PSUs under our 2013 Equity Incentive Plan that are outstanding and held by our non-employee directors and executive officers.

Severance Policy

In July 2013, our compensation committee adopted and approved a Change of Control Severance Policy for Officers (which we refer to as the “Severance Policy”), which was last updated on October 4, 2021. All of our executive officers and certain of our non-executive officers (collectively referred to as “eligible employees”) are generally eligible for severance payments and benefits under the Severance Policy, subject to executing a participation agreement and the conditions described below. Each eligible employee may receive payments and benefits upon a termination of employment without “cause” or a resignation for “good reason” (as such terms are generally defined below) (each of which, we refer to as a “qualified termination of employment”) anytime from three months prior to a change of control through 12 months following a change of control of Mandiant (which we refer to as the “change of control period”). In addition, eligible employees may receive severance payments and benefits for qualified terminations of employment outside of the change of control period. The payments and benefits in the Severance Policy vary based on whether an eligible employee is an officer for purposes of Section 16 of the Exchange Act (which we refer to as a “Tier 1 Executive,”) or is not an officer for purposes of Section 16 of the Exchange Act (which we refer to as a “Tier II Executive.”).

In the event of a qualified termination of employment, during the change of control period, an eligible employee will receive the following:

•

Tier I Executive or Tier II Executive:

•

lump-sum cash payment equal to 12 months’ base salary;

•

lump-sum cash payment equal to a pro-rata target bonus for the year of termination;

•

100% acceleration of all then-unvested equity awards with unvested performance awards vesting at maximum level; and

•

paid COBRA continuation for 12 months.

In the event of a termination of employment without “cause” (as generally defined below) outside of the change of control period, an eligible employee will receive the following:

•

Tier I Executive:

•

lump-sum cash payment equal to 12 months’ base salary; and

•

paid COBRA continuation for 12 months.

•

Tier II Executive:

TABLE OF CONTENTS

•

lump-sum cash payment equal to six months’ base salary; and

•

paid COBRA continuation for six months.

All severance payments and benefits under the Severance Policy are subject to the eligible employee executing and not revoking a general release of clams in favor of Mandiant. Payments and benefits under the Severance Policy replace any then-existing severance and/or change of control payment and benefit arrangements that an eligible employee had previously been entitled to receive. All of our named executive officers have entered into a participation agreement with us.

For purposes of the Severance Policy, “cause” means, generally, an eligible employee’s:

•

unauthorized use or disclosure of our confidential information or trade secrets, which use or disclosure causes material harm to us;

•

material breach of any agreement between us and the eligible employee;

•

material failure to comply with our written policies or rules;

•

conviction of, or plea of “guilty” or “no contest” to, a felony under the laws of the United States or any State;

•

gross negligence or willful misconduct in the performance of the named executive officer’s duties;

•

continuing failure to perform assigned duties after receiving written notification of the failure from our chief executive officer; or

•

failure to cooperate in good faith with a governmental or internal investigation of Mandiant or our directors, officers or employees, if we have requested such cooperation;

provided, however, that “cause” will not be deemed to exist in certain of the events above unless the eligible employee has been provided with (i) 30 days’ written notice by the Mandiant Board of the act or omission constituting “cause” and (ii) 30 days’ opportunity to cure such act or omission, if capable of cure.

For purposes of the Severance Policy, “good reason” means generally any of the following without an eligible employee’s consent:

•

a material reduction in the eligible employee’s duties, authority, reporting relationship, or responsibilities;

•

a material reduction in the eligible employee’s annual cash compensation;

•

a requirement to relocate to a location more than 20 miles from the eligible employee’s then-current office location;

•

a material breach by us of the eligible employee’s employment agreement or any other agreement between the eligible employee and us; or

•

a failure by any successor entity to assume the Severance Policy.

Golden Parachute Compensation

The following table sets forth the information required by Item 402(t) of Regulation S-K regarding certain compensation for each of Mandiant’s named executive officers that is based on, or that otherwise relates to, the merger. This compensation is referred to as “golden parachute” compensation by the applicable SEC disclosure rules, and in this section such term is used to describe the merger-related compensation payable to Mandiant’s named executive officers. Mandiant’s “named executive officers” for purposes of the disclosure in this proxy statement are Messrs. Bailey, Mandia, Robbins, Verdecanna and Watters and Ms. King. For additional details regarding the terms of the payments quantified below, see the sections of this proxy statement captioned “— Interests of Mandiant’s Directors and Executive Officers in the Merger — Treatment of Equity-Based Awards” and “— Interests of Mandiant’s Directors and Executive Officers in the Merger — Severance Policy.”

The amounts in the table are estimated using the following assumptions and such additional assumptions as may be set forth in the footnotes to the table:

TABLE OF CONTENTS

•

the effective time of the merger will occur on June 30, 2022 (which is the assumed closing date of the merger solely for purposes of this proxy statement, including this golden parachute compensation disclosure);

•

each named executive officer will experience a qualifying termination of his or her employment at the effective time of the merger that results in severance benefits becoming payable to such named executive officer under the Severance Policy;

•

the equity awards that are outstanding as of March 18, 2022 represent the full extent of equity awards that Mandiant will have granted to the named executive officer through June 30, 2022, the assumed closing date of the merger, provided that such equity awards that are expected to vest or be paid in accordance with their terms prior to June 30, 2022 are treated as having vested or been paid in accordance with their terms and excluded from the amounts in the table; and

•

the number of shares of our common stock subject to Mandiant PSUs will be determined at actual levels of achievement for any completed Mandiant PSUs and at maximum levels of achievement for any uncompleted Mandiant PSUs.

The amounts reported below are estimates based on these and other assumptions that may or may not actually occur or be accurate on the relevant date. Accordingly, the ultimate values to be received by a named executive officer in connection with the merger may differ from the amounts set forth below. Mandiant’s named executive officers will not receive pension, non-qualified deferred compensation or tax reimbursements in connection with the merger. In addition, the estimated amounts below do not attempt to quantify any reduction that may be required as a result of any cutback under Section 280G of the Code. As required by applicable SEC rules, all estimated amounts below that are determined using the per share value of our common stock have been calculated based on the per share price.

Name	Cash ($)(2)		Equity ($)(3)		Perquisites / benefits ($)(4)		Total ($)
Kevin R. Mandia		880,000		12,619,088		30,397		13,529,485
Frank E. Verdecanna		656,000		6,041,824		4,059		6,701,883
Peter Bailey		625,000		6,020,250		30,397		6,675,647
Alexa King(1)		—		—		—		—
William T. Robbins		855,000		7,698,560		30,397		8,583,957
John Watters		1,200,000		8,732,824		30,397		9,963,221

(1)

Ms. King ceased to serve as our Executive Vice President, Corporate and Legal Affairs, General Counsel, and Secretary effective November 1, 2021. Ms. King is not eligible to participate in the Severance Policy and will not receive any benefits based on or otherwise relating to the merger.

(2)

The estimated amount for each named executive officer represents the “double-trigger” cash severance payments to which the named executive officer may become entitled under the Severance Policy in connection with a qualifying termination during the change of control period, as described in further detail in the section of this proxy statement captioned “— Int

	ANNEX A – AGREEMENT AND PLAN OF MERGER					A-114
	ANNEX B – Section 262 of the Delaware General Corporation Law					B-1
	ANNEX C – Opinion of Goldman Sachs & Co. LLC					C-1
	ANNEX D-1 – Mandiant Voting Agreement with Kevin R. Mandia					D-1-1
	ANNEX D-2 – Mandiant Voting Agreement with Blackstone Delta Lower Holdings DE L.P. and BTO FD Delta Holdings DE L.P.					D-2-1
	ANNEX D-3 – Mandiant Voting Agreement with ClearSky Security Fund I LLC and ClearSky Power & Technology Fund II LLC					D-3-1

	Parties Involved in the Merger					34
	Effect of the Merger					34
	Effect on Mandiant if the Merger is Not Completed					35
	Per Share Price					35
	Background of the Merger					36
	Recommendation of the Mandiant Board and Reasons for the Merger					46
	Opinion of Goldman Sachs & Co. LLC					50
	Projected Financial Information					59
	Interests of Mandiant’s Directors and Executive Officers in the Merger					61
	Closing and Effective Time of the Merger					69
	Appraisal Rights					69
	Accounting Treatment					75
	Material U.S. Federal Income Tax Consequences of the Merger					75
	Regulatory Approvals Required for the Merger					78
	The Voting Agreements					79
	Delisting and Deregistration of Our Common Stock					80
	Litigation Relating to the Merger
	PROPOSAL 1: ADOPTION OF THE MERGER AGREEMENT					81
	PROPOSAL 2: APPROVAL, ON A NON-BINDING, ADVISORY BASIS, OF CERTAIN					82
	PROPOSAL 3: ADJOURNMENT OF THE SPECIAL MEETING					83
	THE MERGER AGREEMENT					84
	Closing and Effective Time of the Merger					84
	Effects of the Merger; Certificate of Incorporation; Bylaws; Directors and Officers					85
	Conversion of Shares					85
	Payment Agent, Exchange Fund and Exchange and Payment Procedures					87
	Representations and Warranties					88
	Conduct of Business Pending the Merger					91
	Conversion of Convertible Preferred Stock					95
	Security Assessment; Code Scan; Remediation					96
	No Solicitation of Other Acquisition Offers					96
	The Mandiant Board’s Recommendation; Board Recommendation Change					98
	Stockholder Meeting					99
	Employee Benefits					100
	Efforts to Close the Merger					100
	Indemnification and Insurance					102
	Conditions to the Closing of the Merger					103
	Termination of the Merger Agreement					104
	Termination Fees and Remedies					105
	Fees and Expenses					106
	No Third Party Beneficiaries					106
	Amendment and Waiver					107
	Governing Law and Venue					107
	Waiver of Jury Trial					107
	SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT					108
	FUTURE STOCKHOLDER PROPOSALS					111
	WHERE YOU CAN FIND MORE INFORMATION					112
	MISCELLANEOUS					113