AEGN Aegion Corporation

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April 1, 2021

Dear Stockholder:

You are cordially invited to attend a special meeting of stockholders (which we refer to as the “special meeting”) of Aegion Corporation (which we refer to as “Aegion” or the “Company”). The special meeting will be held virtually via the Internet on May 14, 2021, beginning at 8:30 a.m., Central Daylight Time. As part of our precautions regarding the COVID-19 (coronavirus) pandemic, we are sensitive to the public health and travel concerns that our stockholders may have, as well as any quarantines or other protocols that governments may impose. As a result, the special meeting will be held in a virtual meeting format only via live webcast. There will not be a physical meeting location. You will be able to attend the special meeting online and vote your shares electronically by visiting www.virtualshareholdermeeting.com/AEGN2021SM (which we refer to as the “special meeting website”).

At the special meeting, you will be asked to consider and vote upon (1) a proposal to adopt the Agreement and Plan of Merger, dated as of February 16, 2021 (which we refer to as the “original merger agreement”), as amended by Amendment No. 1 thereto, dated March 13, 2021 (which we refer to as the “amendment to the merger agreement”), among Carter Intermediate, Inc. (which we refer to as “Parent”), Carter Acquisition, Inc. (which we refer to as “Merger Sub”), which is a direct wholly-owned subsidiary of Parent, and Aegion. We refer to the original merger agreement, as amended by the amendment to the merger agreement and as it may be further amended from time to time, as the “merger agreement” or the “amended merger agreement”. Pursuant to the merger agreement, subject to the satisfaction of certain conditions contained in the merger agreement (described in more detail in the section entitled “The Merger Agreement—Other Covenants and Agreements—Conditions to the Merger” beginning on page 89 of this proxy statement), Merger Sub will merge with and into Aegion (which we refer to as the “merger”), and Aegion will become a wholly-owned subsidiary of Parent, (2) a non-binding advisory proposal to approve specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement and (3) a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement.

If the merger is completed, you will be entitled to receive $27.00 in cash, without interest and less applicable withholding taxes, for each share of Aegion common stock you own (unless you have properly exercised your appraisal rights with respect to such shares).

The Aegion Board of Directors (which we refer to as the “Board”) unanimously determined that the merger agreement and the transactions contemplated by the merger agreement are fair to and in the best interests of Aegion and its stockholders, and declared it advisable for Aegion to enter into the merger agreement and authorized and approved the execution, delivery and performance by Aegion of the merger agreement and the consummation of the transactions contemplated by the merger agreement. The Board unanimously recommends that you vote (i) “FOR” the proposal to adopt the merger agreement, (ii) “FOR” the proposal to approve, on a non-binding advisory basis, specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement and (iii) “FOR” the proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement.

As previously announced and as further described in the enclosed proxy statement, Aegion has received an unsolicited, non-binding proposal from a third party to acquire all of the outstanding shares of Aegion common stock. As of the date of the enclosed proxy statement, such third party had not yet completed its review of the due diligence information with which it had been provided access and on which the terms of such third party’s proposal was conditioned, nor has such third party completed the financing arrangements contemplated by its proposal. As of the date of the enclosed proxy statement, the Board has not made a determination as to whether

such proposal is a “Superior Proposal” that would give rise to a right in favor of Aegion to terminate the merger agreement in order to enter into a definitive agreement with respect to such proposal, subject to observation of Parent’s right under the merger agreement to further amend the merger agreement such that such proposal (or any revised proposal arising therefrom) would no longer be a “Superior Proposal.” This is a developing situation and we will update the enclosed proxy statement before the vote is taken at the special meeting. We are sending the enclosed proxy statement to you now in order to prevent delay, and minimize the risk of the occurrence of a material adverse effect or other impediment prior to closing, assuming that the transactions contemplated by the merger agreement will continue to represent the best transaction available to Aegion following the completion of such third party’s due diligence process. However, Aegion cannot predict the outcome of such third party’s due diligence process, whether such proposal will become a “Superior Proposal”, the results of any negotiations with such third party or Parent that may follow such proposal or whether Aegion will receive any other proposal from such third party, Parent or any other prospective acquiror.

The enclosed proxy statement provides detailed information about the special meeting, the merger agreement and the merger. Copies of the original merger agreement and the amendment to the merger agreement are attached as Annex A and Annex B, respectively, to the proxy statement. The proxy statement also describes the actions and determinations of the Board in connection with its evaluation of the merger agreement and the merger. We encourage you to read the proxy statement and its annexes, including the original merger agreement and the amendment to the merger agreement, carefully and in their entirety. You may also obtain more information about Aegion from documents we file with the Securities and Exchange Commission (which we refer to as the “SEC”) from time to time.

All Aegion stockholders of record at the close of business on March 31, 2021 are welcome to attend the special meeting via the special meeting website. Every stockholder’s vote is important to us, so it is important that your shares are represented at the special meeting whether or not you plan to attend via the special meeting website. To ensure that you will be represented, please promptly vote by submitting the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone. You will also be able to attend the special meeting online and vote your shares electronically by visiting the special meeting website. If you plan to attend the special meeting, you will need the 16-digit control number included on your proxy card or voting instruction form that accompanies your proxy materials. If you attend the special meeting and vote via the special meeting website, your vote will revoke any proxy that you have previously submitted. If you hold your shares in street name, you should instruct your broker, bank or other nominee how to vote in accordance with the voting instruction form you will receive from your broker, bank or other nominee.

Your vote is very important, regardless of the number of shares that you own. We cannot consummate the merger unless the proposal to adopt the merger agreement is approved by the affirmative vote of the holders of a majority of the shares of Aegion common stock issued and outstanding and entitled to vote thereon. The failure of any stockholder to vote by ballot via the special meeting website, to submit a signed proxy card or to grant a proxy electronically over the Internet or by telephone or an abstention from voting 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 broker, bank or other nominee on how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement.

If you have any questions or need assistance voting your shares of Aegion common stock, please contact Innisfree M&A Incorporated, our proxy solicitor, by calling (877) 687-1874 toll-free if located in the U.S. or Canada, or +1 (412) 232-3651 if located elsewhere.

Thank you for your support of Aegion.

Sincerely,

 

Mark A. Menghini

Senior Vice President, General Counsel and Secretary

Neither the SEC nor any state securities regulatory agency has approved or disapproved of the transactions described in this document, including the merger, or determined if the information contained in this document is accurate or adequate. Any representation to the contrary is a criminal offense.

The accompanying proxy statement is dated April 1, 2021 and, together with the enclosed form of proxy card, is first being mailed to stockholders of record of Aegion on or about April 5, 2021.

 

The approval, on a non-binding advisory basis, of the proposal regarding specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement requires the affirmative vote of the holders of a majority of the issued and outstanding shares of Aegion common stock that are present or represented by proxy at the special meeting via the special meeting website and entitled to vote thereon, so long as a quorum is present. An abstention from voting will have no effect on the proposal to approve, on a non-binding advisory basis, specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on this proposal, so long as a quorum is otherwise present.

The affirmative vote of the holders of a majority of the issued and outstanding shares of Aegion common stock that are present or represented by proxy at the special meeting via the special meeting website and entitled to vote thereon, whether or not a quorum is present, is required to approve the proposal to approve one or more adjournments of the special meeting, if necessary or appropriate. An abstention from voting will have no effect on the proposal to approve one or more adjournments of the special meeting. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on this proposal.

Only stockholders of record as of the close of business on March 31, 2021 are entitled to notice of the special meeting and to vote at the special meeting or at any adjournment or postponement thereof. A list of stockholders entitled to vote at the special meeting will be available in our corporate offices located at 17988 Edison Avenue, Chesterfield, MO 63005 during regular business hours for a period of at least ten (10) days before the special meeting and at the place of the special meeting during the meeting. If our headquarters are closed for health and safety reasons related to the COVID-19 (coronavirus) pandemic during such period, the list of stockholders will be made available for inspection upon request via email to corporatesecretary@aegion.com, subject to our satisfactory verification of stockholder status, and will also be made available online during the special meeting via the special meeting website.

The Aegion Board of Directors unanimously recommends that you vote (i) “FOR” the proposal to adopt the merger agreement, (ii) “FOR” the proposal to approve, on a non-binding advisory basis, specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement and (iii) “FOR” the proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement.

By Order of the Board of Directors,

Mark A. Menghini

Senior Vice President, General Counsel and Secretary

April 1, 2021

Chesterfield, Missouri

The following questions and answers are intended to address briefly some commonly asked questions regarding the special meeting, the merger agreement and the transactions contemplated thereby. These questions and answers may not address all questions that may be important to you as an Aegion stockholder. Please refer to the section entitled “Summary” preceding this section and the more detailed information contained elsewhere in this proxy statement, the annexes to this proxy statement, including the original merger agreement and the amendment to the merger agreement, and the documents referred to in this proxy statement, all of which you should read carefully. The original merger agreement and the amendment to the merger agreement are attached as Annex A and Annex B, respectively, to the proxy statement.

To ensure that you will be represented, we encourage you to promptly vote by submitting the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone. In certain circumstances, the special meeting could be adjourned to another time or place. All references in our proxy materials to special meeting include any adjournment or postponement of the special meeting.

If you are a beneficial owner of shares held in street name and wish to vote via the special meeting website, you should contact your broker, bank or other nominee to obtain your specific control number and further instructions. If you are not a holder of record as of the close of business on the record date, you will be permitted to vote at the special meeting only if you have a valid proxy from a holder of record as of the close of business on the record date.

For a discussion of the factors that the Board considered in determining to approve the execution and delivery of the merger agreement by Aegion and to recommend the adoption of the merger agreement, please see the section entitled “The Merger (Proposal 1)—Recommendation of the Board and Reasons for the Recommendation” beginning on page 50 of this proxy statement. In addition, in considering the recommendation of the Board with respect to the merger agreement, you should be aware that some of our directors and executive officers have interests that may be different from, or in addition to, the interests of Aegion stockholders generally. For a discussion of these interests, please see the section entitled “The Merger (Proposal 1)—Interests of Aegion’s Directors and Executive Officers in the Merger” beginning on page 64 of this proxy statement.

As of the close of business on the record date, there were 30,740,819 shares of Aegion common stock issued and outstanding, and entitled to vote at the special meeting. Each share of Aegion common stock issued and outstanding as of the close of business on the record date will be entitled to one vote on each matter submitted to a vote at the special meeting.

If you submit a proxy but fail to provide voting instructions or abstain on any of the proposals listed on the proxy card, your shares will be counted for the purpose of determining whether a quorum is present at the special meeting.

If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, these shares will not be counted for purposes of determining whether a quorum is present for the transaction of business at the special meeting.

In the event that a quorum is not present at the special meeting, we expect to adjourn or postpone the special meeting from time to time until we solicit enough proxies to obtain a quorum.

Beneficial Owner. If you are a beneficial owner of shares held in street name, under applicable stock exchange rules the broker, bank or other nominee that holds your shares may generally vote on routine proposals but cannot vote without instructions on non-routine matters unless they have discretionary authority. None of the proposals to be voted on at the special meeting are considered routine proposals. As a result, if the broker, bank or other nominee that holds your shares does not receive instructions from you on how to vote your shares, a “broker non-vote” will occur. Therefore, we urge you to give voting instructions to your broker. Shares represented by such “broker non-votes” will not be counted as present or represented by proxy in determining whether there is a quorum. A “broker non-vote” will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. Your abstention will have no effect on the compensation advisory proposal or the adjournment proposal.

The directors and executive officers of Aegion have interests in the merger that may be different from, or in addition to, the interests of Aegion stockholders generally. These interests are described in more detail in the section entitled “The Merger (Proposal 1)—Interests of Aegion’s Directors and Executive Officers in the Merger” beginning on page 64 of this proxy statement.

Please note that only your last-dated proxy will count. Attending the special meeting without taking one of the actions described above will not in itself revoke your proxy. Please note that if you want to revoke your proxy by mailing a new proxy card or by sending a written notice of revocation to Aegion, you should ensure that you send your new proxy card or written notice of revocation in sufficient time for it to be received by Aegion before the special meeting (such new proxy cards or written notices of revocation received by or with our last mail delivery before the special meeting begins will be counted).

If you hold your shares in street name through a broker, bank or other nominee, you will need to follow the instructions provided to you by your broker, bank or other nominee in order to revoke your proxy or submit new voting instructions. You may also revoke your proxy by obtaining your specific control number and further instructions from your broker, bank or other nominee that holds the shares of record and voting your shares via the special meeting website.

The requisite number of shares to approve the compensation advisory proposal is a majority of the shares of Aegion common stock cast on the proposal at the special meeting at which a quorum is present. The presence at the special meeting of the holders of record of a majority of the shares entitled to vote, present via the special meeting website or represented by proxy, at the close of business on the record date will constitute a quorum. An abstention from voting will have no effect on the compensation advisory proposal. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on the compensation advisory proposal, so long as a quorum is otherwise present.

The requisite number of shares to approve adjournment proposal is a majority of the shares of Aegion common stock cast on the proposal at the special meeting, whether or not a quorum is present. An abstention from voting will have no effect on the adjournment proposal. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on the adjournment proposal.

Only shares of common stock that are issued and outstanding as of the close of business on the record date are eligible to be voted on each of the three (3) proposals and will be counted for purposes of determining whether a quorum is present at the special meeting.

If the merger agreement is not adopted by the Aegion stockholders, the merger cannot close and Aegion would not be entitled under any circumstance to the parent termination fee.

The record date for stockholders entitled to vote at the special meeting is March 31, 2021. If you transfer your shares of Aegion common stock after the record date but before the closing of the merger, unless you have granted a “proxy” to the purchaser as part of the transfer, you will have the right to vote at the special meeting although you will have transferred your right to receive the merger consideration in the merger.

exchanging your shares of Aegion common stock evidenced by stock certificates for the merger consideration. If your shares of Aegion common stock are held in street name by your broker, bank or other nominee, you will receive instructions from your broker, bank or other nominee as to what action, if any, you need to take in order to effect the surrender of your street name shares in exchange for the merger consideration. Please do not send in any documentation of evidence of ownership now.

Each Aegion stockholder is urged to read the discussion in the section entitled “The Merger (Proposal 1)—Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 69 of this proxy statement and to consult its tax advisor to determine the particular U.S. federal, state or local or non-U.S. income or other tax consequences to it of 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 any state, local or non-U.S. tax laws or tax treaties.

of Aegion to terminate the merger agreement in order to enter into a definitive agreement with respect to such proposal, subject to observation of Parent’s right under the merger agreement to further amend the merger agreement such that such proposal (or any revised proposal arising therefrom) would no longer be a “Superior Proposal.” This is a developing situation and we will update this proxy statement before the vote is taken at the special meeting. We are sending this proxy statement to you now in order to prevent delay, and minimize the risk of the occurrence of a material adverse effect or other impediment prior to closing, assuming that the transactions contemplated by the merger agreement will continue to represent the best transaction available to Aegion following the completion of such third party’s due diligence process. However, Aegion cannot predict the outcome of such third party’s due diligence process, whether such proposal will become a “Superior Proposal”, the results of any negotiations with such third party or Parent that may follow such proposal or whether Aegion will receive any other proposal from such third party, Parent or any other prospective acquiror.

Innisfree M&A Incorporated

Stockholders in the US and Canada May Call Toll Free: (877) 687-1874

Stockholders in Other Locations May Call: (412) 232-3651

Banks and Brokers May Call Collect: (212) 750-5833

If your broker, bank or other nominee holds your shares, you should also call your broker, bank

or other nominee for additional information.

This proxy statement contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to risks, uncertainties and assumptions that are difficult to predict. Forward-looking statements are predictions based on expectations and projections about future events, and are not statements of historical fact. Forward-looking statements include statements concerning business strategy, plans and prospects, among other things, including anticipated trends and developments in and management plans for our business and the markets in which we operate. In some cases, you can identify these statements by forward-looking words, such as “estimate,” “expect,” “anticipate,” “project,” “plan,” “intend,” “believe,” “forecast,” “foresee,” “likely,” “may,” “should,” “goal,” “target,” “might,” “will,” “could,” “predict,” and “continue,” the negative or plural of these words and other comparable terminology. All forward-looking statements included in this proxy statement are based upon information available to us as of the filing date of this proxy statement, and, except to the extent required by applicable law, we undertake no obligation to update any of these forward-looking statements for any reason. You should not place undue reliance on forward-looking statements. The forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance, or achievements to differ materially from those expressed or implied by these statements. Important factors that could cause actual results to differ materially from those contained in any forward-looking statement include the factors identified in Aegion’s annual report on Form 10-K for the year ended December 31, 2020, under the heading “Risk Factors,” as updated from time to time by Aegion’s quarterly reports on Form 10-Q and other documents of Aegion on file or in this proxy statement filed with the SEC by Aegion, and the following factors:

Consequently, all of the forward-looking statements we make in this proxy statement are qualified by the information contained or incorporated by reference herein, including, but not limited to, (i) the information contained under this heading and (ii) the information contained under the heading “Risk Factors” and information in our consolidated financial statements and notes thereto included in our most recent filing on Form 10-K and subsequent periodic and interim report filings (see “Where You Can Find Additional Information” beginning on page 109 of this proxy statement). No assurance can be given that these are all of the factors that could cause actual results to vary materially from the forward-looking statements.

We are furnishing this proxy statement to Aegion stockholders as part of the solicitation of proxies by the Board for use at the special meeting or any adjournment or postponement thereof. This proxy statement provides Aegion stockholders with the information they need to know to be able to vote or instruct their vote to be cast at the special meeting or any adjournment or postponement thereof.

This proxy statement is being furnished to our stockholders as part of the solicitation of proxies by the Board for use at the special meeting to be held virtually via the Internet on May 14, 2021 at www.virtualshareholdermeeting.com/AEGN2021SM, beginning at 8:30 a.m., Central Daylight Time. or at any adjournment or postponement thereof. Aegion has chosen to hold the special meeting solely by means of remote location (via the Internet) and not in a physical location given the current public health impacts of COVID-19 (coronavirus) and our desire to promote the health and safety of Aegion stockholders, as well as Aegion directors, officers, employees and other constituents.

Only individuals who were Aegion stockholders as of the close of business on the record date and their authorized representatives may attend the special meeting. If you plan to attend the special meeting, you will need the 16-digit control number included on your proxy card or voting instruction form that is accompanied by your proxy materials. If you are a beneficial owner of shares held in street name and wish to vote in person at the special meeting, you should contact your broker, bank or other nominee to obtain your specific control number and further instructions. To ensure that you will be represented, even if you plan to attend the special meeting via the special meeting website, we encourage you to promptly vote by submitting the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone. If you attend the special meeting and vote by ballot via the special meeting website, your vote will revoke any proxy that you have previously submitted. Please contact your broker, bank or other nominee for instructions regarding obtaining your specific control number and further instructions.

This proxy statement and the enclosed form of proxy are first being mailed to our stockholders of record on or about April 5, 2021.

The primary purpose of the special meeting is for our stockholders to consider and vote upon the proposal to adopt the merger agreement. Our stockholders holding a majority of the shares of Aegion common stock issued and outstanding at the close of business on the record date and entitled to vote thereon must adopt the merger agreement in order for the merger to occur. If our stockholders fail to adopt the merger agreement, the merger will not occur. Copies of the original merger agreement and the amendment to the merger agreement are attached as Annex A and Annex B, respectively, to this proxy statement, and the material provisions of the merger agreement are summarized in the section of this proxy statement entitled “The Merger Agreement” beginning on page 73 of this proxy statement.

In addition, our stockholders are being asked to approve the compensation advisory proposal, which is the approval, on a non-binding advisory basis, of specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement, the value of which is disclosed in the table entitled “Golden Parachute Compensation” and the notes accompanying that table in the section entitled “Advisory Vote on Specified Compensation (Proposal 2)” beginning on page 96 of this proxy statement.

Our stockholders are also being asked to approve the adjournment proposal, which is one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement.

The holders of record of Aegion common stock as of the close of business on March 31, 2021, the record date for the special meeting, are entitled to receive notice of and to vote at the special meeting. As of the close of business on the record date, 30,740,819 shares of Aegion common stock were issued and outstanding.

The presence at the special meeting of the holders of record of a majority of the shares of Aegion common stock entitled to vote, present via the special meeting website or represented by proxy, at the close of business on the record date will constitute a quorum. Once a share is represented at the special meeting, it will be counted for the purpose of determining a quorum at the special meeting. However, if a new record date is set for an adjourned special meeting, then a new quorum will have to be established. Proxies received but marked as abstentions will be included in the calculation of the number of shares considered to be present for the purpose of determining a quorum at the special meeting. “Broker non-votes,” described below under the sub-heading “Providing Voting Instructions by Proxy—Shares of Aegion Common Stock Held in Street Name,” will not be included in the calculation of the number of shares considered to be present for the purpose of determining a quorum at the special meeting.

Holders of Aegion common stock are entitled to one vote on each proposal submitted to a vote at the special meeting for each share of Aegion common stock they own at the close of business on the record date. As of the close of business on the record date, there were 30,740,819 shares of Aegion common stock issued and outstanding.

For Aegion to complete the merger, stockholders holding a majority of the shares of Aegion common stock issued and outstanding at the close of business on the record date and entitled to vote thereon must vote “FOR” the proposal to adopt the merger agreement. A failure to vote your shares of Aegion common stock or an abstention from voting will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise and will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement.

The approval, on a non-binding advisory basis, of the compensation advisory proposal requires the affirmative vote of a majority of the shares of Aegion common stock cast on the proposal, so long as a quorum is present, to vote “FOR” the proposal. An abstention from voting will have no effect on the compensation advisory proposal. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on the compensation advisory proposal, so long as a quorum is otherwise present.

The approval of the adjournment proposal requires the affirmative vote of a majority of the shares of Aegion common stock cast on the proposal, whether or not a quorum is present, to vote “FOR” the proposal. An abstention from voting will have no effect on the adjournment proposal. If your shares are held in street name by your broker, bank or other nominee and you do not instruct the nominee how to vote your shares, a “broker non-vote” will arise but will have no effect on the adjournment proposal.

At the close of business on the record date, directors and executive officers of Aegion were entitled to vote 1,175,199 shares of Aegion common stock, or approximately 3.82% of the shares of Aegion common stock issued and outstanding on that date. We currently expect that Aegion’s directors and executive officers will vote their shares in favor of the proposal to adopt the merger agreement and in favor of the other proposals to be considered at the special meeting, although they have no obligation to do so.

All holders of shares of Aegion common stock as of the close of business on the record date, including stockholders of record and beneficial owners of Aegion common stock registered in the street name of a broker, bank or other nominee, are invited to attend the special meeting via the special meeting website. During the special meeting, Aegion stockholders will be able to vote their shares. If you are a beneficial owner of shares held in street name and wish to vote via the special meeting website, you should contact your broker, bank or other nominee to obtain your specific control number and further instructions.

Stockholders of record who have registered in advance to attend the special meeting will be able to vote at the special meeting via the special meeting website by ballot cast at the special meeting. If you are a beneficial

owner of shares held in street name and wish to vote at the special meeting via the special meeting website, you should contact your broker, bank or other nominee to obtain your specific control number and further instructions.

To ensure that your shares of Aegion common stock are voted at the special meeting, we recommend that you provide voting instructions promptly by proxy, even if you plan to attend the special meeting via the special meeting website.

If you are a stockholder of record, you may provide voting instructions by proxy using one of the methods described below.

If you submit a signed proxy card or submit your proxy by telephone or the internet, but do not specify how you want to vote your shares on a particular proposal, then the proxy holders will vote your shares in accordance with the recommendations of the Board on all matters presented in this proxy statement. If you fail to return your proxy card and you are a holder of record on the record date, unless you attend the special meeting and vote via the special meeting website, the effect will be that your shares of Aegion common stock will not be considered present at the special meeting for purposes of determining whether a quorum is present at the special meeting, will have the same effect as a vote against the proposal to adopt the merger agreement, will have no effect on the vote regarding the compensation advisory proposal, so long as a quorum is otherwise present, and will have no effect on the vote regarding the adjournment proposal.

If your shares are held in the name of a bank, broker or other nominee, you will receive instructions from your bank, broker or other nominee as to how to vote your shares. You must follow the instructions of your bank, broker or other nominee in order for your shares of Aegion common stock to be voted. Telephone and internet voting also will be offered to stockholders owning shares through certain banks, brokers and other nominees. If your shares are not registered in your own name but are held through your bank, broker or other nominee and you plan to vote your shares at the special meeting website, you should contact your bank, broker or other nominee to obtain your specific control number and further instructions.

In accordance with the rules of the Nasdaq, brokers, banks and other nominees that hold shares of Aegion common stock in street name for their customers do not have discretionary authority to vote the shares with respect to the proposal to adopt the merger agreement, the compensation advisory proposal, or the adjournment proposal. Accordingly, if brokers, banks or other nominees do not receive specific voting instructions from the beneficial owner of such shares, they may not vote such shares with respect to these proposals. Under such circumstance, a “broker non-vote” would arise. “Broker non-votes,” if any, will not be considered present at the special meeting for purposes of determining whether a quorum is present at the special meeting, will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement and will have no effect (x) so long as a quorum is otherwise present, on the compensation advisory proposal or (y) on the adjournment proposal. Thus, for shares of Aegion common stock held in street name, only shares of Aegion common stock affirmatively voted “FOR” the proposal to adopt the merger agreement will be counted as a vote “FOR” such proposal.

Any person giving a proxy pursuant to this solicitation has the power to revoke and change it at any time before it is voted. If you are a stockholder of record, you may revoke your proxy at any time before the vote is taken at the special meeting by:

Please note that only your last-dated proxy will count. Attending the special meeting without taking one of the actions described above will not in itself revoke your proxy. Please note that if you want to revoke your proxy by mailing a new proxy card or by sending a written notice of revocation to Aegion, you should ensure that you send your new proxy card or written notice of revocation in sufficient time for it to be received by Aegion before the special meeting (such new proxy cards or written notices of revocation received by or with our last mail delivery before the special meeting will be counted).

If you hold your shares in street name through a broker, bank or other nominee, you will need to follow the instructions provided to you by your broker, bank or other nominee in order to revoke your proxy or submit new voting instructions. You may also revoke your proxy by obtaining your specific control number and further instructions from your broker, bank or other nominee and voting your shares at the special meeting via the special meeting website.

An abstention occurs when a stockholder attends a meeting, either virtually or by proxy, but abstains from voting by checking the box marked “ABSTAIN” on either the ballot, proxy card or voting instruction card submitted by the stockholder. Abstentions will be included as shares of Aegion common stock present or represented at the special meeting for purposes of determining whether a quorum has been achieved. Abstaining from voting will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. Abstaining from voting will have no effect on the compensation advisory proposal or the adjournment proposal.

Although it is not currently expected, the special meeting may be adjourned or postponed if necessary or appropriate, including for the purpose of soliciting a sufficient number of proxies “FOR” the proposal to adopt the merger agreement. In the event that a sufficient number of shares of Aegion common stock is present at the special meeting via the special meeting website or represented by proxy, and voted “FOR” the proposal to adopt the merger agreement at the special meeting such that the Aegion stockholder approval will have been obtained, Aegion does not anticipate that it will adjourn or postpone the special meeting.

The special meeting may be adjourned by the affirmative vote of the holders of a majority of the shares of Aegion common stock cast on the proposal, whether or not a quorum is present. Any adjournment or postponement of the special meeting will allow Aegion stockholders who have already sent in their proxies to revoke them at any time before their use at the special meeting that was adjourned or postponed.

We are paying the cost for the preparation, printing and distribution of the proxy materials. We may use the services of our directors, officers and employees, without additional compensation, to solicit proxies. We will reimburse any holder of record for its reasonable expenses incurred in completing the mailing of stockholder requested proxy materials to the beneficial owners of our common stock. Aegion has engaged Innisfree M&A

Incorporated (which we refer to as “Innisfree”) to assist in the solicitation of proxies for the special meeting. Aegion estimates that it will pay Innisfree a fee of approximately $30,000, plus reimbursement of certain expenses. In addition, Aegion may reimburse its transfer agent, brokerage firms and other persons representing beneficial owners of shares of Aegion common stock for their expenses in forwarding solicitation material to such beneficial owners.

We are permitted to send a single set of proxy materials to stockholders who share the same last name and address. This procedure is called “householding” and is designed to reduce our printing and postage costs. This means that we may send a single set of our proxy materials, containing a single copy of this proxy statement but separate proxy cards or voting instruction forms for each stockholder in your household. We will promptly deliver a separate copy of our proxy materials to you if you contact the Corporate Secretary in writing at Aegion Corporation, 17988 Edison Avenue, Chesterfield, Missouri 63005, or by phone at (800) 325-1159. Such requests by street name holders should be made through their broker, bank or other nominee.

You should not return any evidence of your shares of Aegion common stock or send documents representing Aegion common stock with the proxy card. If the merger is completed, the paying agent for the merger will send to you a letter of transmittal, if applicable, and related materials and instructions for exchanging your shares of Aegion common stock.

Upon the consummation of the merger, each share of Aegion common stock issued and outstanding immediately prior to the effective time, other than shares of Aegion common stock (i) held in the treasury of Aegion or owned by any direct or indirect wholly-owned subsidiary of Aegion , (ii) owned by Merger Sub, Parent or any direct or indirect wholly-owned subsidiary of Parent or (iii) held by stockholders who will have neither voted in favor of the merger nor consented thereto in writing and who will have demanded properly in writing appraisal for such shares in accordance with Section 262 of the General Corporation Law of the State of Delaware (which we refer to as the “excluded shares”), will be cancelled and converted into the right to receive $27.00 in cash, without interest and less applicable withholding taxes. At the effective time of the merger, Aegion stockholders will cease to have ownership interests in Aegion or rights as stockholders of Aegion, except as provided in the merger agreement or by law.

Aegion common stock is currently registered under the Exchange Act and is listed on the Nasdaq under the symbol “AEGN.” As a result of the merger, Aegion will cease to be a publicly traded company and will be a wholly-owned subsidiary of Parent. Following the consummation of the merger, Aegion common stock will be de-listed from the Nasdaq and de-registered under the Exchange Act, in each case in accordance with applicable law, rules and regulations.

The original merger agreement was amended pursuant to the amendment to the merger agreement to (i) increase the per share merger consideration from $26.00 to $27.00 in cash, (ii) increase the parent termination fee payable by Parent under certain circumstances set forth in the merger agreement, from $60 million to $70 million, (iii) increase the company termination fee payable by Aegion under certain circumstances set forth in the merger agreement, from $30 million to $40 million. The amendment to the merger agreement also amended the definition of “Superior Proposal” in the original merger agreement to expressly require the Board to take into account (i) the financing (in addition to the legal, financial, regulatory and other) aspects of an acquisition proposal in the Board’s determination of whether such acquisition proposal amounts to a superior proposal and (ii) the anticipated timing to consummate the transactions contemplated by the merger agreement, and all legal, financial, regulatory, financing and other aspects, of an acquisition proposal as factors in the Board’s determination of whether or not such acquisition proposal is a superior proposal. The equity commitment letter (as further described in the section entitled “The Merger Agreement—Financing—Equity Commitment Letter” beginning on page 68 of this proxy statement) was amended to increase the New Mountain fund’s equity commitment by the amount of additional aggregate merger consideration indicated by the amendment to the merger agreement, from $420 million to $453 million, and the limited guarantee (as further described in the sections entitled “The Merger Agreement—Financing—Limited Guarantee” beginning on page 68 and 69, respectively, of this proxy statement) was amended to increase the amount of the New Mountain fund’s limited guarantee by the $10 million incremental increase to the parent termination fee.

The Aegion Board of Directors (which we refer to as the “Board”) and Aegion management regularly review and assess Aegion’s performance, risks, opportunities and strategy, including reviews of developments in the industries in which we operate and opportunities to increase stockholder value. These reviews have included, from time to time, potential strategic alternatives and other enhancements to Aegion’s business plan and include the comprehensive global realignment and restructuring plan approved by the Board on July 28, 2017 and effected in the years following such approval. As part of their ongoing evaluation of Aegion’s business, the Board and Aegion management regularly communicate with and consider the views of stockholders.

On May 3, 2019, Charles R. Gordon, President and Chief Executive Officer of Aegion, received an email from representatives of the financial advisor to an unidentified third party (which we refer to as “Party A”) requesting a telephone call to discuss a possible strategic opportunity involving Aegion.

On May 7, 2019, Mr. Gordon had a conference call with representatives of Party A’s financial advisor, during which call representatives of Party A’s financial advisor identified Party A as their client, described Party A’s interest in exploring a possible acquisition of Aegion and requested a meeting between Aegion management and certain representatives of Party A. Mr. Gordon responded that any proposals regarding a potential acquisition of Aegion would need to be addressed to the Board.

On May 14, 2019, the Board held a special meeting, with certain members of Aegion management in attendance. Representatives of Aegion’s outside legal counsel, Shearman & Sterling LLP (which we refer to as “Shearman &

Sterling”), also attended that meeting. At that meeting, the Board discussed the potential proposal from Party A regarding a possible acquisition of Aegion by Party A. Representatives of Shearman & Sterling and the Board discussed the Board’s fiduciary duties and representatives of Shearman & Sterling noted the importance of identifying any potential conflicts of interest that any Board members might have with respect to any potential acquisition of Aegion by Party A, in order to allow the Board to consider whether individual members could participate in any discussions regarding such a transaction. Following a discussion of potential conflicts of interest with representatives of Shearman & Sterling, it was determined that none of the Board members had any conflicts of interest with respect to a potential transaction between Aegion and Party A.

On May 28, 2019, Aegion received a non-binding indication of interest letter from Party A expressing Party A’s desire to pursue an acquisition of Aegion. The letter, addressed to Stephanie A. Cuskley, Chairwoman of the Board, and Mr. Gordon, contained a bid range of $22.00 to $23.00 per share of Aegion common stock in cash and indicated that such acquisition would be funded through a combination of debt and equity capital.

On June 4, 2019, the Board held a special meeting, with certain members of Aegion management in attendance. Representatives of Shearman & Sterling also attended that meeting. At that meeting, the attendees again discussed the proposal in Party A’s indication of interest letter and Aegion’s potential proposed responses thereto. Representatives of Shearman & Sterling and the Board also discussed the Board’s fiduciary duties and the advisability and timing of engaging a financial advisor in the event the Board decided to proceed with any consideration of any potential sale transaction. The Board decided that Party A’s proposal was not compelling enough to engage in discussions, that Aegion could deliver higher value to its stockholders through the execution of Aegion’s long range strategic plan and that on that basis, Party A’s proposal should be declined.

On June 5, 2019, Ms. Cuskley sent an email to Party A noting that the Board had carefully reviewed Party A’s indication of interest letter and believed that Aegion could deliver higher value to its stockholders through the execution of Aegion’s long range strategic plan and accordingly declined Party A’s proposal. The email indicated that the Board would give due consideration to a revised indication of interest from Party A if one were submitted on more favorable terms.

On June 7, 2019, Ms. Cuskley received an email from Party A indicating that Party A remained open to increasing the price per share of Aegion common stock included in its indication of interest letter should Party A be encouraged by a review of additional information regarding Aegion’s prospects. The email accordingly requested the opportunity to review the long range strategic plan referenced in Ms. Cuskley’s email of June 5, 2019 and perhaps other due diligence information. Party A committed that, upon review of such material, Party A would quickly revert to the Board regarding its ability to resubmit a more favorable proposal.

On June 10, 2019, Ms. Cuskley, Mr. Gordon and other representatives of Aegion held a conference call with representatives of Aegion’s outside counsel, Shearman & Sterling. During that call the participants discussed Party A’s proposal and Aegion’s proposed response.

On June 17, 2019, the Board held another special meeting, with certain members of Aegion’s management in attendance. At that meeting, the attendees discussed Party A’s proposal and Aegion’s proposed response. The Board decided that Party A would be provided with the opportunity to meet with members of Aegion’s management for the limited purpose of allowing Aegion to discuss with Party A publicly available information related to Aegion’s strategic plans.

On June 19, 2019, Ms. Cuskley sent an email to Party A informing Party A that the Board was willing to entertain having representatives of Party A meet with Mr. Gordon and other members of Aegion’s senior management team, for the limited purpose of allowing Aegion to discuss with Aegion’s publicly stated strategic plans with Party A, on the belief that such a discussion would assist Party A in developing a more favorable proposal. In her email, Ms. Cuskley made clear that Aegion’s management would not provide any material non-public information to Party A at the proposed meeting.

On July 1, 2019, in order to facilitate a meeting and discussion between Party A and representatives of Aegion, Party A and Aegion executed a confidentiality agreement requiring Party A to maintain confidentiality with respect to any discussions between them.

On July 10, 2019, Mr. Gordon attended a dinner meeting in St. Louis, Missouri with a representative of New Mountain Capital, L.L.C. (which we refer to as “New Mountain”), with whom Mr. Gordon was familiar from his past business dealings while employed by another organization. The New Mountain representative had

previously called Mr. Gordon, informed him that he would be in St. Louis, Missouri on July 10 and asked that Mr. Gordon meet him for dinner. The New Mountain representative arrived at that meeting with a representative of a second party (which we refer to as “Party B”). At that meeting, the representatives of New Mountain and Party B expressed their interest in jointly acquiring Aegion through the merger of Aegion and an affiliate of Party B. Following that meeting, Mr. Gordon sent an e-mail to the Board to inform the Board of such meeting and that he had informed the representatives of New Mountain and Party B that Aegion’s current strategy was to remain a publicly listed company and that any decision to sell Aegion would be the Board’s responsibility and, accordingly, any such proposals would have to be made to the Board.

On July 12, 2019, Ms. Cuskley and Mr. Gordon and other members of Aegion’s senior management team met with representatives of Party A to discuss Aegion’s long-term growth prospects. At that meeting, members of Aegion’s senior management team discussed with representatives of Party A publicly available information related to Aegion’s strategic plans.

On July 18, 2019, Aegion received a revised non-binding indication of interest letter from Party A containing a bid range of $23.00 to $23.50 per share of Aegion common stock in cash and proposing that Aegion grant Party A period of exclusivity to facilitate Party A’s due diligence.

On July 22, 2019, Aegion received a non-binding indication of interest letter, addressed to Ms. Cuskley and Mr. Gordon, from New Mountain, Party B and an affiliate of Party B (which we refer to collectively as the “Party B Group”) expressing their joint interest in pursuing discussions with Aegion regarding a possible acquisition of Aegion by the Party B Group. That letter contained a bid range of $20.00 to $21.00 per share of Aegion common stock in cash, was subject to the completion of due diligence, assumed the cash-out of all outstanding stock awards, deferred stock and options and noted that the proposal was intended to be financed through a combination of debt and equity capital, with certain affiliates of New Mountain and Party B making equity capital commitments in connection with the proposed transaction. The letter also requested that Aegion grant the Party B Group a 45-day period of exclusivity to facilitate their evaluation of a proposed transaction, with such exclusivity period to automatically renew for additional 15-day periods unless either party provided written notice of its desire not extend the exclusivity period.

On July 26, 2019, the Board held a special meeting, with certain members of management also in attendance. In addition, the Board invited Centerview Partners, LLC (which we refer to as “Centerview Partners”) and Shearman & Sterling, to attend. Aegion was familiar with Centerview Partners as a result of Aegion’s previous engagement of Centerview Partners as Aegion’s financial advisor in connection with Aegion’s acquisition of Brinderson, L.P. in 2013, and a subsequent engagement of Centerview Partners to assist Aegion with the analysis and consideration of various strategic alternatives. During the July 26, 2019 meeting, representatives of Centerview Partners presented their initial views on a potential sale of Aegion and recommended that Centerview Partners conduct a full assessment of Aegion’s strategic alternatives over the course of the following four to five week period in parallel with preparing for the launch of a potential process to determine third party interest in an acquisition of Aegion. The Board authorized Centerview Partners to prepare a report comparing Aegion’s strategic alternatives against what might be realizable in a sale of Aegion. The Board also authorized Aegion management to begin initial preparations for a launch of a confidential sale process, pending the Board’s decision on whether or not to pursue such process.

On August 5, 2019, the Board held a meeting at which certain members of Aegion management were in attendance. At that meeting, the Board reviewed the credentials and experience of Centerview Partners and reviewed a preliminary analysis of the options for Aegion to consider with respect to soliciting third party interest for the potential acquisition of Aegion. Following that discussion, the Board discussed its experience with Centerview Partners and whether to move forward with engagement discussions. The Board agreed to request a formal engagement letter and proposal from Centerview Partners. The Board also reviewed the credentials and experience of certain representatives of Shearman & Sterling and authorized the engagement of Shearman & Sterling as outside counsel with respect to a potential sale of Aegion. After consideration and further discussion of the two pending indications of interest from Party A and the Party B Group, the Board determined that it could deliver higher value to its stockholders through the execution of its long range strategic plan and that both parties should accordingly be notified that Aegion was not willing to proceed with discussions on the basis of the prices indicated in their respective indication of interest letters, and determined that Centerview Partners be instructed to inform Party A of such message.

On August 6, 2019, Ms. Cuskley received an email from a representative of New Mountain expressing the Party B Group’s continued interest in discussing the proposal set forth in their most recent indication of interest letter and requesting a meeting to facilitate such discussion.

On August 7, 2019, Ms. Cuskley had a telephonic meeting with representatives of Centerview Partners to discuss potential responses to the most recent indication of interest letters received from Party A and the Party B Group.

On August 8, 2019, Ms. Cuskley sent an email to a representative from Party A thanking Party A for its continued interest in Aegion. Ms. Cuskley informed Party A that Aegion was working with Centerview Partners to review Aegion’s various strategic alternatives, and that a representative from Centerview Partners would be reaching out to Party A to further discuss Party A’s interest in Aegion.

On August 9, 2019, at the Board’s request, representatives of Centerview Partners held a telephonic meeting with representatives of Party A. During that meeting, at the instruction of the Board, Centerview Partners informed Party A that the Board was not prepared to proceed with discussions with Party A based upon the price levels indicated in Party A’s indication of interest letter received on July 18, 2019.

Also on August 9, 2019, Ms. Cuskley had a telephonic meeting with representatives of New Mountain during which Ms. Cuskley informed New Mountain that the Board was not currently prepared to engage in a discussion with the Party B Group based upon the price levels indicated in the Party B Group’s most recent indication of interest letter as the Board believed that it could deliver higher value to its stockholders through the execution of its long range strategic plan.

On August 27, 2019, Mr. Gordon received a telephone call from the Chief Executive Officer of another potentially interested party (which we refer to as “Party C”) inquiring about Aegion’s interest in a merger with Party C, to which Mr. Gordon responded that any such discussions were a matter for the Board and that the Board would revert with any response. Following that telephone call, Mr. Gordon informed Ms. Cuskley and Centerview Partners of the call.

On September 3, 2019, Centerview Partners provided the Board with relationship disclosure with respect to its prior dealings with Party A, New Mountain and Party B.

On September 4, 2019, the Board held a special meeting. In attendance were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, the Board and management reviewed a base case long-range plan for Aegion and underlying assumptions prepared by management. Representatives of Centerview Partners then presented the findings of Centerview Partners’ preliminary valuation analysis of Aegion and a comparison of Aegion’s potential strategic alternatives as well as various considerations related thereto, including the potential timeline of any potential process for the sale of Aegion, the indications of interest received from Party A and the Party B Group, the inquiry from Party C and a consideration of a list of 29 potential strategic and financial counterparties, including Party A, the Party B Group and Party C, that could be approached as part of any potential process for the sale of Aegion. Centerview Partners then left the meeting and the Board, members of management and representatives of Shearman & Sterling reviewed and discussed the terms of the draft engagement letter for Centerview Partners and the key terms that would be included in the confidentiality agreement that would be required to be executed by any potentially interested party in order to participate in any strategic alternative process. The Board and representatives of Shearman & Sterling then discussed the Board’s fiduciary duties generally and in connection with any strategic alternative process. The Board also considered and discussed the relationship disclosure that was provided by Centerview Partners on September 3, 2019 and determined that nothing in such disclosure would preclude its engagement as financial advisor in connection with the strategic alternatives under consideration by the Board. The Board then entered executive session to discuss the various presentations and advice it had received at the meeting. Following discussions, the Board approved the engagement of Centerview Partners on the terms set forth in the draft engagement letter that had been presented to and reviewed by the Board, authorized management to proceed with a confidential auction process for the potential sale of Aegion and authorized Centerview Partners to contact 19 potential counterparties, that the Board and Centerview Partners believed were most likely to be interested in proposing a transaction, from the list of potential counterparties that was presented to the Board during that meeting.

On September 9, 2019, Aegion and Centerview Partners executed an engagement letter for the engagement of Centerview Partners as Aegion’s financial advisor with respect to a confidential auction process for the potential sale of Aegion, as previously approved by the Board.

Beginning on September 9, 2019, at the instruction of the Board, Centerview Partners contacted a total of 19 potential counterparties authorized by the Board in connection with a potential acquisition of Aegion, including 11 financial and eight strategic firms and included Party A, the Party B Group and Party C, to gauge interest in a potential acquisition of Aegion. Of the 19 potential counterparties, nine declined to participate in the process.

Beginning on September 11, 2019, Aegion negotiated and executed confidentiality agreements with, ten potentially interested parties, including Party C on September 18, 2019, Party A on September 24, 2019 and the Party B Group on September 25, 2019. The draft confidentiality agreement distributed to the potentially interested parties contained a two year non-solicit provision, a two year standstill provision, a “don’t ask, don’t waive” provision prohibiting the potentially interested parties from requesting that Aegion waive or amend the standstill restrictions to allow the applicable potentially interested party to make another proposal during the standstill period and a prohibition on sharing confidential information with potential financing sources without Aegion’s consent. Negotiations with the potentially interested parties typically included discussion around the periods applicable to those standstill and non-solicit provisions, the inclusion of a “don’t ask, don’t waive” provision and the ability of the potentially interested parties to share confidential information with potential financing sources. Of the ten potentially interested parties with whom Aegion executed confidentiality agreements, two negotiated for a reduced 12-month standstill period, seven negotiated for a reduced 18-month standstill period and one accepted the two-year standstill period proposed in the draft confidentiality agreement. Additionally, seven of the potentially interested parties negotiated for an 18-month non-solicit period and three of the potentially interested parties accepted the two year non-solicit period proposed in the draft confidentiality agreement. All of the potentially interested parties ultimately accepted the “don’t ask, don’t waive” provision as well as the limitations on their ability to share confidential information with potential financing sources without the prior written consent of Aegion.

Between September 18, 2019 and September 30, 2019, members of Aegion’s senior management team hosted a management presentation with each of the ten potentially interested parties who executed confidentiality agreements.

Following the management presentations, one of the ten potentially interested parties declined to participate any further in the process.

During the week of September 30, 2019, a quality of earnings report, summary financial model and formal process letter requesting non-binding indications of interest by October 17, 2019 was sent to the nine remaining potentially interested parties.

On October 17, 2019, Aegion received non-binding indication of interest letters from Party A and the Party B Group containing bids of $23.80 and $23.25 per share, respectively, of Aegion common stock in cash. The seven remaining potentially interested parties declined to submit a non-binding indication of interest.

On October 22 and October 23, 2019, the Board held a regularly scheduled quarterly meeting. In attendance were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, representatives of Centerview Partners presented a summary of the auction process to date, an analysis of the indications of interest submitted by Party A and the Party B Group as compared to various valuation metrics and a summary of related considerations and potential next steps. Representatives of Shearman & Sterling also provided the Board with an update of their fiduciary duties in the context of the current process, following which all advisors left the meeting. The Board and Aegion management also discussed updated relationship disclosure provided by Shearman & Sterling and Centerview Partners with respect to their dealings with Party A, New Mountain and Party B prior to the meeting and the Board determined that nothing in such disclosure would preclude the Board from relying on the advice of Shearman & Sterling or Centerview Partners. Management then left the meeting and the Board entered executive session to discuss the information it had received. The Board came to the conclusion that the bid prices included in the indication of interest letters submitted by Party A and the Party B Group were not supportive of pursuing a potential sale of Aegion, that Aegion could deliver higher value to its stockholders through the execution of its long range strategic plan and that, accordingly, the sale process should be terminated.

Following the Board’s determination to terminate the sale process, the Board instructed Aegion management to continue to execute Aegion’s long range strategic plan, including the multi-year restructuring effort to simplify and drive a narrower focus on Aegion’s core markets.

On October 25, 2019, Shearman & Sterling sent letters on behalf of Aegion to each of the ten parties with whom Aegion signed confidentiality agreements instructing such parties to either return or destroy any confidential information received from Aegion in connection with the auction process pursuant to the terms and conditions of such confidentiality agreements.

Beginning in March 2020, as a result of the impacts and uncertainties of the COVID-19 pandemic on Aegion’s businesses, Aegion took a number of counteractive measures, including suspending certain restructuring activities, initiating additional restructuring actions, effecting headcount reductions across certain business segments, eliminating merit increases for 2020 and temporarily reducing the cash salaries of all executive officers during the second quarter and supplementing such reductions with equity awards in order to conserve cash.

On July 30, 2020, Mr. Gordon announced his plans to retire as President and Chief Executive Officer of Aegion and that he would remain in his role until his successor was named and successfully onboarded. In connection with this announcement, Aegion launched a formal executive search to identify Mr. Gordon’s successor.

On September 30, 2020, Ms. Cuskley received a telephone call from a representative of New Mountain. During that telephone call, Ms. Cuskley was informed of New Mountain’s continued interest in exploring various strategic alternatives within the infrastructure industry, including facilitating Aegion’s growth through a potential strategic combination among Aegion and an affiliate of Party B.

On October 20, 2020, the Board held a regularly scheduled quarterly meeting. In attendance were members of management. At that meeting, the attendees discussed certain potential strategic opportunities, including in relation to New Mountain’s interest in facilitating Aegion’s growth through a potential strategic combination among Aegion and an affiliate of Party B, as expressed to Ms. Cuskley during the September 30, 2020 telephone call.

On November 3, 2020, Aegion and New Mountain executed a mutual confidentiality agreement pursuant to which each party agreed to maintain confidentiality over any confidential information shared between the parties in connection with an exploration of a potential acquisition by Aegion of the affiliate of Party B that was a member of the Party B Group.

On November 3, 2020, Party B provided Aegion with a document containing certain updates on the business of the Party B affiliate.

On November 4, 2020, members of Aegion’s senior management, along with representatives of Centerview Partners, conducted a virtual meeting with representatives of the Party B affiliate and New Mountain to review the document provided by Party B on November 3, 2020. During that meeting, Aegion’s senior management team was informed that the Party B affiliate’s business was not being actively marketed for sale, but that Party B would entertain any interest in or proposals with respect to the affiliate should Aegion have further interest. Following that meeting, Aegion engaged in no further discussions with Party B or New Mountain regarding a potential acquisition by Aegion of the Party B affiliate.

On November 17, 2020, New Mountain sent Aegion a term sheet which set forth an outline of financing terms under which New Mountain would provide PIPE financing to Aegion in conjunction with Aegion’s potential acquisition of an affiliate of Party B. Aegion did not respond to New Mountain’s term sheet, nor did Aegion continue with any further discussions with Party B concerning Party B’s affiliate.

On December 7, 2020, Ms. Cuskley received a telephone call from a representative of New Mountain. During that telephone call, Ms. Cuskley was informed of New Mountain’s continued interest, in New Mountain’s own capacity and not on behalf of the Party B Group, in pursuing and facilitating various strategic combinations within the infrastructure industry and also New Mountain’s possible continued interest in acquiring Aegion. Ms. Cuskley reiterated the Board’s focus of maximizing value for its stockholders and that the Board would analyze any indication of interest it received in light of that goal and against all available alternatives.

On December 14, 2020, Aegion announced a plan to divest its Energy Services business in advancement of Aegion’s strategy to expand its focus on the water and wastewater markets and to further reduce Aegion’s exposure to the oil and gas markets.

On December 16, 2020, Aegion received a non-binding indication of interest letter from New Mountain for the acquisition of Aegion at a bid price of $24.00 per share of Aegion common stock in cash, assuming the cash-out of all shares of Aegion common stock issuable under any outstanding options, performance stock units, restricted stock units, deferred stock units and any other equity-related securities, that Aegion would achieve consensus 2020 full-year financial results and that all cash to be generated would remain in the business through closing. The indication of interest letter indicated that such acquisition would be funded through a combination of debt and equity capital and included a highly confident letter from a potential source of debt financing for up to $550 million of debt financing. The indication of interest letter also indicated that New Mountain was prepared to commence and complete its due diligence within 30 days (assuming timely responses to due diligence requests and reasonable access to management) and requested that Aegion agree to provide New Mountain with a 30 day exclusivity period within which to negotiate and agree to a transaction, with such 30 day exclusivity period to be automatically extended by additional 15-day periods unless either party notified the other that it did not wish to extend the exclusivity period at least 24 hours prior to the expiration of the then-applicable exclusivity period. The indication of interest letter also provided that, in exchange for Aegion agreeing to grant New Mountain with such exclusivity, New Mountain would be willing to accept a reasonable go-shop provision in any definitive purchase agreement to be entered into between the parties.

On December 22, 2020, the Board held a telephonic meeting. In attendance at that meeting were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, the terms of New Mountain’s indication of interest letter were considered and discussed. At that meeting, representatives of Shearman & Sterling discussed the Board’s fiduciary duties in the current scenario and reminded the Board that New Mountain was still subject to the standstill obligations contained in the confidentiality agreement executed by New Mountain on September 25, 2019. The Board requested that management prepare a renewed five year forecast for Aegion to be considered by the Board in connection with New Mountain’s indication of interest letter. The Board resolved to meet again on January 11, 2021 to consider that updated forecast and make a decision in response to New Mountain’s indication of interest letter. The Board also requested that Centerview Partners deliver an updated relationship disclosure with respect to its prior dealings with New Mountain, which Centerview Partners delivered later that day.

On December 23, 2020, Ms. Cuskley made a telephone call to New Mountain to inform New Mountain that the Board had met to have an initial discussion regarding New Mountain’s indication of interest letter and had decided that, before proceeding with any discussions in relation thereto, the Board would be reconvening on January 11, 2021 to consider a renewed five year forecast being prepared by Aegion management.

On January 5, 2021, in anticipation of the possibility of future discussions, Aegion and New Mountain executed an amendment to the confidentiality agreement signed by the parties on September 25, 2019 which, among other things, extended the term of the confidentiality agreement for two years following the date of the amendment and extended New Mountain’s standstill and non-solicit obligations pursuant to such confidentiality agreement for 18 months following the date of the amendment.

On January 11, 2021, the Board held a telephonic meeting. In attendance at that meeting were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, representatives of Shearman & Sterling presented the Board with Shearman & Sterling’s relationship disclosure in relation to New Mountain. Representatives of Centerview Partners presented the Board with a valuation analysis of Aegion prepared by Centerview Partners. The Board reviewed the five year forecast prepared by Aegion management, requested certain revisions thereto and discussed several options for responding to New Mountain’s indication of interest letter, ultimately deciding that the $24.00 per share bid price contained in New Mountain’s indication of interest letter was not compelling enough to proceed with negotiating a transaction with New Mountain and that a revised increased proposal should be requested from New Mountain. In order to facilitate a revised increased proposal from New Mountain, the Board authorized Aegion management to meet with representatives of New Mountain to present certain information related to Aegion’s business, including the renewed five year forecast prepared by Aegion management. The Board also reviewed and discussed the relationship disclosures that had been provided by Shearman & Sterling at that meeting and by Centerview Partners on December 22, 2020 and determined that nothing in such disclosures would preclude the Board from relying on the advice of Shearman & Sterling or Centerview Partners. The Board tentatively set the next Board

meeting for February 2, 2021 in anticipation of an increased bid from New Mountain. The Board also approved an addendum to the engagement letter executed by Aegion and Centerview Partners on September 9, 2019 extending the term of Aegion’s engagement of Centerview Partners which was subsequently executed by Aegion and Centerview Partners on January 12, 2021.

On January 12, 2021, Centerview Partners notified New Mountain of the Board’s decision to provide New Mountain with access to senior management and incremental due diligence information to facilitate a higher, revised proposal. Centerview Partners also informed New Mountain that their request for exclusivity would not be accommodated based upon the existing proposed terms.

On January 14 and 15, 2021, members of Aegion management hosted management presentations with representatives of New Mountain to provide New Mountain with an update on Aegion’s business, including the renewed five year forecast prepared by Aegion management. New Mountain was provided with a presentation document reflecting the information presented during those meetings. Representatives of Centerview Partners were also in attendance at the management presentations.

On January 16, 2021, New Mountain and its legal and financial advisers were granted “data room” access to perform due diligence. Between January 16, 2021 and February 16, 2021, New Mountain and its advisers continued with their due diligence review, including requesting responses from Aegion to a number of diligence requests.

On January 22, 2021, Centerview Partners sent New Mountain a process letter on behalf of Aegion requesting an updated proposal from New Mountain by 12:00 p.m. on February 1, 2021.

On February 1, 2021, Aegion received an updated indication of interest letter from New Mountain containing a bid price of $24.60 per share of Aegion common stock in cash, assuming the cash-out of all shares of Aegion common stock issuable under any outstanding options, performance stock units, restricted stock units, deferred stock units and any other equity-related securities, that Aegion would achieve consensus 2020 full-year financial results and that all cash to be generated would remain in the business through closing. The indication of interest letter was otherwise largely on the same terms as the indication of interest letter submitted by New Mountain on December 16, 2020, with New Mountain anticipating that it would be able to complete its due diligence within two weeks and requesting that Aegion agree to provide New Mountain with a 14 day exclusivity period within which to negotiate and agree to a transaction, with such 14 day exclusivity period to be automatically extended by additional 7-day periods unless either party notified the other that it did not wish to extend the exclusivity period at least 24 hours prior to the expiration of the then-applicable exclusivity period. The indication of interest letter did not indicate that New Mountain would be willing to accept a go-shop provision in any definitive purchase agreement to be entered into between the parties, but in subsequent conversations between New Mountain and Centerview Partners, New Mountain confirmed its willingness to accept a go-shop provision in any definitive agreement.

On February 2, 2021, the Board held a special meeting to consider New Mountain’s updated indication of interest letter. In attendance at that meeting were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, representatives of Centerview Partners presented the Board with a summary of New Mountain’s updated indication of interest letter, the diligence that had been facilitated for New Mountain in order to evaluate a potential acquisition of Aegion, Centerview Partners’ revised valuation analysis of Aegion and consideration of potential next steps. Representatives of Shearman & Sterling reviewed with the Board the exclusivity provisions included in New Mountain’s indication of letter setting forth the exclusive basis on which New Mountain proposed Aegion and New Mountain would proceed. The Board decided that the $24.60 per share bid price contained in New Mountain’s updated indication of interest letter was not compelling enough to proceed with negotiating a transaction with New Mountain and that a best and final offer should be solicited from New Mountain. In light of the fact that a “go-shop” provision was anticipated to be included in any definitive agreement with New Mountain, the Board did not deem it necessary to reach out to other potential purchasers, including Party A. The Board instructed Centerview Partners to request a best and final offer from New Mountain and indicated that the Board would agree to proceed exclusively with New Mountain at a revised offer price of $26.25 per share or more of Aegion common stock in cash.

Later on February 2, 2021, at the instruction of the Board, Centerview Partners requested that New Mountain submit a best and final offer for the acquisition of Aegion by 9:00 a.m. the next day and indicated that the Board was prepared to pursue a transaction if such offer was for $26.25 per share of Aegion common stock in cash.

On February 3, 2021, Aegion received an updated indication of interest letter from New Mountain containing a bid price of $26.00 per share of Aegion common stock in cash and based on the same conditions and assumptions set forth in the indication of interest letter submitted by New Mountain on February 1, 2020, with New Mountain anticipating a target signing and announcement date of February 16, 2021. New Mountain’s revised proposal provided that, in exchange for the substantial increase in New Mountain’s bid price, any definitive agreement to be entered into between the parties would not include a “go-shop” provision. New Mountain indicated to Centerview Partners that the offer of $26.00 per share of Aegion common stock in cash contained in its updated indication of interest letter was New Mountain’s best and final offer.

On February 3, 2021, the Board held a special meeting to consider New Mountain’s updated indication of interest letter. In attendance at that meeting were members of management and representatives of Centerview Partners and Shearman & Sterling. During the meeting, representatives of Centerview Partners presented the Board with a summary of New Mountain’s updated indication of interest letter and a preliminary valuation of Aegion. At the meeting, the attendees also discussed the frequency and effectiveness of “go-shop” provisions in similar deals. Shearman & Sterling reviewed with the Board the terms of a draft exclusivity agreement which, if approved by the Board, could be provided to New Mountain if the Board chose to proceed with New Mountain on an exclusive basis. Shearman & Sterling highlighted for the Board the key terms of the draft exclusivity agreement, and how they differed from the terms of the exclusivity provisions of New Mountain’s indication of interest letter, including that New Mountain would be granted exclusivity only until 5:00 p.m. on February 16, 2021 and, provided the parties were working in good faith to execute a definitive agreement for the proposed sale of Aegion to New Mountain at such time, an automatic extension of such exclusivity period to 5:00 p.m. on February 18, 2021 unless New Mountain notified Aegion that it was unable to sign a definitive agreement for the proposed transaction based on the terms contained in its indication of interest letter. The Board resolved to authorize Aegion management, Centerview Partners and Shearman & Sterling to proceed with negotiating a potential deal for the sale of Aegion to New Mountain at the price of $26.00 per share of Aegion common stock in cash on the terms set forth in New Mountain’s latest indication of interest letter, other than the exclusivity provisions. The Board authorized Shearman & Sterling to share the draft exclusivity agreement containing the terms outlined to the Board with representatives of Centerview Partners for them to provide to New Mountain.

On February 4, 2021, Aegion and New Mountain executed the exclusivity agreement on the terms approved by the Board on February 3, 2021.

Later on February 4, 2021, Shearman & Sterling provided a draft merger agreement for the sale of Aegion to New Mountain and its advisers. The draft merger agreement contained representations and warranties, closing conditions, covenants and other provisions customary for transactions of the type contemplated by New Mountain’s indication of interest letter and contemplated a one-step cash merger of an entity to be newly formed by New Mountain (which we refer to as “Merger Sub”) with and into Aegion with Aegion surviving such merger as a wholly-owned subsidiary of another entity to be newly formed by New Mountain (which we refer to as “Parent”). The draft merger agreement also provided for, among other things, the delivery of an equity commitment letter from an investment fund managed by New Mountain (which we refer to as the “New Mountain fund”) for the capitalization of Parent, a debt commitment letter from the lenders party thereto to Merger Sub and a limited guarantee from the New Mountain fund in favor of Aegion guaranteeing all obligations of Parent and Merger Sub under the merger agreement other than the obligation to pay any amounts to be sourced from the debt financing and, consistent with New Mountain’s indication of interest letter, included a no-solicitation provision and did not include a “go-shop” provision. The no-solicitation provision of the draft merger agreement provided that Aegion would provide New Mountain with a three business day period within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger in the event of a superior proposal or an intervening event or terminating the merger agreement in the event of a superior proposal, and one subsequent two business day period within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any material changes to the financial or other material terms of a superior proposal. The draft merger agreement also contemplated the payment by Aegion of a company termination fee in an amount equal to 3% of the equity value of the transaction in the event of termination of the merger agreement in certain circumstances, including where the merger agreement is terminated in certain circumstances and Aegion subsequently consummates a transaction for the acquisition of Aegion by a party other than New Mountain within nine months of such termination, and the payment by Parent of a parent termination fee in an amount equal to 7.5% of the equity

value of the transaction in the event of termination of the merger agreement in certain circumstances. The draft merger agreement did not contain a closing condition related to New Mountain’s ability to consummate any financing, and contained a “hell or high water” antitrust covenant requiring New Mountain to take any and all actions necessary to avoid or eliminate each and every impediment under any antitrust law, conduct of business covenants that enabled Aegion to conduct its business in the ordinary course consistent with past practice and an employee benefits matters covenant requiring that New Mountain maintain certain employee benefits for continuing employees for a period of two years following closing.

On February 7, 2021, New Mountain’s legal counsel, Ropes & Gray LLP (which we refer to as “Ropes & Gray”), sent a revised draft merger agreement to Shearman & Sterling. Among other things, the revised draft merger agreement proposed a company termination fee of $35 million (amounting to approximately 4% of the equity value of the transaction), a parent termination fee of $50 million (amounting to approximately 6% of the equity value of the transaction) and a requirement that Aegion reimburse Parent for its reasonable and out-of-pocket expenses up to $5 million in the event of termination of the merger agreement due to a failure to obtain the required stockholder vote to approve the merger or the Board changing its recommendation in favor of the merger in response to an event materially affecting Aegion and its subsidiaries that was not known by the Board prior to signing of the merger agreement. The revised draft merger agreement also provided that the company termination fee would be payable if the merger agreement was terminated in certain circumstances and Aegion subsequently consummates a transaction for the acquisition of Aegion by a party other than New Mountain within 12 months of such termination. The revised draft merger agreement also revised the no-solicitation provision to require that Aegion would provide New Mountain with an unlimited number of subsequent two business day periods (following the initial three business day period) within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any changes to the financial or other material terms of a superior proposal. In addition, the revised draft merger agreement provided that the limited guarantee from the New Mountain fund in favor of Aegion would be limited to a guarantee of Parent’s obligation to pay the parent termination fee in accordance with the terms of the merger agreement. The revised draft merger agreement also expanded the scope of Aegion’s representations and warranties, increased the limitations that would be placed on Aegion’s ability to operate its business between signing and closing of the merger agreement as a result of more restrictive conduct of business covenants and revised the employee benefits matters covenant by reducing the scope of the employee benefits New Mountain would be required to maintain following closing and providing that New Mountain would only be required to maintain such benefits for one year following closing.

On February 10, 2021, Ropes & Gray sent initial drafts of an equity commitment letter and limited guarantee to Shearman & Sterling. Among other things, the limited guarantee provided for a guarantee in favor of Aegion by the New Mountain fund limited to Parent’s obligation to pay the parent termination fee when due in accordance with the terms of the merger agreement.

Also on February 10, 2021, Shearman & Sterling sent a revised draft merger agreement to Ropes & Gray. Among other things, the revised draft merger agreement reinstated the proposals for the company termination fee and parent termination fee to be amounts equal to 3% and 7.5% of the equity value of the transaction, respectively The revised draft merger agreement also provided that any amount that Aegion would be required to reimburse Parent for its reasonable and out-of-pocket expenses was subject to agreement and would only be payable in the event of termination of the merger agreement due to the Board changing its recommendation in favor of the merger in response to an event materially affecting Aegion and its subsidiaries that was not known by the Board prior to signing of the merger agreement. The revised draft merger agreement also revised the no-solicitation provision to require that Aegion would only be required to provide New Mountain with a maximum of two additional two business day periods (following the initial three business day period) within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any changes to the financial or other material terms of a superior proposal. In addition, the revised draft merger agreement provided that the limited guarantee from the New Mountain fund in favor of Aegion would extend to all obligations of Parent and Merger Sub under the merger agreement other than the obligation to pay any amounts to be sourced from the debt financing. The revised draft merger agreement also reduced the scope of Aegion’s representations and warranties, reduced the limitations that would be placed on Aegion’s ability to operate its business between signing and closing of the merger agreement by providing for less restrictive conduct of

business covenants and revised the employee benefits matters covenant by increasing the scope of the employee benefits New Mountain would be required to maintain following closing and providing that New Mountain would be required to maintain such benefits for 18 months following closing.

On February 11, 2021, New Mountain sent a draft debt commitment letter to Centerview Partners.

Also on February 11, 2021, Shearman & Sterling sent an initial draft disclosure schedule to the merger agreement to Ropes & Gray, which, among other things, provided for the ability of Aegion to set compensation for 2021 which the Board normally acted on in late February of each year.

On February 12, 2021, Ropes & Gray sent a revised draft of the merger agreement to Shearman & Sterling. Among other things, the revised draft merger agreement reinstated their proposed company termination fee of $30 million, increased the parent termination fee to $56 million and proposed that Aegion would also be required to reimburse Parent for its reasonable and out-of-pocket expenses up to $5 million in the event of termination of the merger agreement due to a failure to obtain the required stockholder vote to approve the merger under circumstances where the company termination fee was not payable. The revised draft merger agreement also revised the no-solicitation provision to require that Aegion would provide New Mountain with an unlimited number of subsequent 2 business day periods (following the initial 3 business day period) within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any changes to the financial or other material terms of a superior proposal. In addition, the revised draft merger agreement provided that the limited guarantee from the New Mountain fund in favor of Aegion would be limited to a guarantee of Parent’s obligation to pay the parent termination fee in accordance with the terms of the merger agreement. The revised draft merger agreement also revised the “hell or high water” antitrust covenant to provide that New Mountain would only be required to use reasonable best efforts to avoid or eliminate each and every impediment under any antitrust law. The revised draft merger agreement also revised the employee benefits matters covenant by reducing the scope of the employee benefits New Mountain would be required to maintain following closing and providing that New Mountain would only be required to maintain such benefits for one year following closing.

Also on February 12, 2021, Shearman & Sterling sent comments to the draft debt commitment letter to Ropes & Gray.

Later on February 12, 2021, representatives of Shearman & Sterling and representatives of Ropes & Gray participated in a conference call to discuss the revised draft merger agreement shared by Ropes & Gray earlier that day and the parties’ positions on certain issues, including the parties’ respective proposals on the company termination fee and the parent termination fee, Ropes & Gray’s revisions to the “hell or high water” antitrust covenant, the scope of employee benefits that New Mountain would be required to provide continuing employees and the period for which New Mountain would be required to provide such benefits pursuant to the employee benefits covenant, and the obligations to which the New Mountain fund’s guarantee under the limited guarantee would extend.

On February 13, 2021, Shearman & Sterling sent revised drafts of the merger agreement, the equity commitment letter and limited guarantee, as well as further updates to the disclosure schedule to the merger agreement addressing various matters including to allow Aegion for additional flexibility to set 2021 employee compensation, to Ropes & Gray. Among other things, the revised merger agreement provided that Aegion would only be required to reimburse Parent for its reasonable and out-of-pocket expenses up to an amount to be agreed in the event of termination of the merger agreement due to the Board changing its recommendation in favor of the merger in response to an event materially affecting Aegion and its subsidiaries that was not known by the Board prior to signing of the merger agreement. The revised draft merger agreement also noted that the amounts of the company termination fee and the parent termination fee were subject to further discussion and agreement among the parties. The revised draft merger agreement also revised the no-solicitation provision to require that Aegion would only be required to provide New Mountain with a maximum of three additional periods (following the initial three business day period) within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any changes to the financial or other material terms of a superior proposal, with the length of such period to be reduced by one business day each time. In addition, the revised draft merger agreement provided that the limited guarantee from the New Mountain fund in favor of Aegion would extend to

all obligations of Parent and Merger Sub under the merger agreement other than the obligation to pay any amounts to be sourced from the debt financing and the revised draft of the limited guarantee provided for the specific payment, indemnification and reimbursement obligations of Parent and Merger Sub under the merger agreement which the New Mountain fund would guarantee in favor of Aegion, including payment of the parent termination fee. The revised draft merger agreement also revised the employee benefits matters covenant by increasing the scope of the employee benefits New Mountain would be required to maintain following closing and providing that New Mountain would be required to maintain such benefits for 18 months following closing. In addition, the revised draft merger agreement reinstated the “hell or high water” antitrust covenant requiring New Mountain to take any and all actions necessary to avoid or eliminate each and every impediment under any antitrust law.

Later on February 13, 2021, Ropes & Gray sent a revised draft of the disclosure schedule to the merger agreement to Shearman & Sterling which, among other things, reduced Aegion’s ability to take certain actions with respect to 2021 employee compensation matters.

On February 14, 2021, Ropes & Gray sent revised drafts of the merger agreement, equity commitment letter and limited guarantee, as well as further updates to the disclosure schedule to the merger agreement, to Shearman & Sterling. Among other things, the revised draft merger agreement reinstated their proposed company termination fee of $30 million, increased their proposal on the parent termination fee to $60 million and also reduced the maximum amount that Aegion would be required to reimburse Parent for its reasonable and out-of-pocket expenses in the event of termination of the merger agreement due to a failure to obtain the required stockholder vote to approve the merger to $4 million The revised draft merger agreement also revised the no-solicitation provision to require that Aegion would be required to provide New Mountain with an unlimited number of additional periods (following the initial three business day period) within which to negotiate modifications to the terms of the merger agreement prior to withdrawing or changing the Board’s recommendation in favor of the merger or terminating the merger agreement in the event of any changes to the financial or other material terms of a superior proposal, with the length of such period to be reduced to two business days in the first instance and one business day for each subsequent instance. In addition, the revised draft merger agreement provided that the limited guarantee from the New Mountain fund in favor of Aegion would be limited to a guarantee of Parent’s obligation to pay the parent termination fee in accordance with the terms of the merger agreement and the revised draft limited guarantee covered the same specific payment, indemnification and reimbursement obligations of Parent and Merger Sub under the merger agreement as included in Shearman &Sterling’s February 13, 2021 draft which the New Mountain fund would guarantee in favor of Aegion, including payment of the parent termination fee. The revised draft merger agreement also revised the employee benefits matters covenant by reducing the scope of the employee benefits New Mountain would be required to maintain following closing and providing that New Mountain would only be required to maintain such benefits for one year following closing.

Later on February 14, 2021, representatives of Ropes & Gray and Shearman & Sterling participated in a conference call to discuss the open points in the revised drafts of the merger agreement, equity commitment letter and limited guarantee, including the no-solicitation provision negotiation period, the scope of employee benefits that New Mountain would be required to provide continuing employees and the period for which New Mountain would be required to provide such benefits pursuant to the employee benefits covenant, matters relating to 2021 employee compensation, the amounts of the company termination fee and the parent termination fee, and to clarify that the parties were in agreement on the obligations to which the New Mountain fund’s guarantee under the limited guarantee would extend.

Between February 14, 2021 and the morning of February 16, 2021, Shearman & Sterling and Ropes & Gray exchanged draft documentation to finalize the merger agreement, disclosure schedule to the merger agreement, equity commitment letter and limited guarantee. Throughout this period, several conference calls were conducted among Aegion, New Mountain and their respective representatives and advisers for purposes of finalizing New Mountain’s diligence, negotiating the terms of the draft documentation and the proposed acquisition of Aegion by New Mountain.

During the afternoon of February 15, 2021, New Mountain held its final investment committee meeting to review near final drafts of the merger agreement, the equity commitment letter, the limited guarantee and to approve the

merger. Following that meeting, representatives of New Mountain notified representatives of Centerview Partners that the New Mountain investment committee had approved the merger agreement, the equity commitment letter and the limited guarantee, in each case subject to finalization, and had approved the merger.

On the evening of February 15, 2021, the Board held a special meeting. In attendance were members of management and representatives of Centerview Partners and Shearman & Sterling. Members of the Board had been provided with a set of meeting materials, including a summary of the terms and conditions of the merger agreement prepared by representatives of Shearman & Sterling and a financial analysis prepared by representatives of Centerview Partners. During the meeting, representatives of Shearman & Sterling discussed the Board’s fiduciary duties in the context of a potential acquisition of Aegion and reviewed with the Board the actions it had taken since May of 2019. Shearman & Sterling also reviewed for the Board the terms of the proposed merger agreement and the resolution of certain key issues, including with respect to the circumstances under which the $60 million parent termination fee, the $30 million company termination fee and the $4 million expense reimbursement could become payable such as, in the case of Aegion’s expense reimbursement obligation, if the Aegion stockholders were not to approve the transaction in the absence of a competing proposal or if the Board were to change its recommendation in favor of the merger in response to an event materially affecting Aegion and its subsidiaries that was not known by the Board prior to signing of the merger agreement. Shearman & Sterling also discussed with the Board various aspects of New Mountain’s financing covenants in the merger agreement and the fact that the limited guarantee to be provided by the New Mountain fund would cover the payment of the parent termination fee and certain other of Parent’s and Merger Sub’s indemnification obligations under the merger agreement, as opposed to all of Parent’s and Merger Sub’s obligations other than in respect of the debt commitment. The Board and Aegion management also provided their views on the restrictions on the conduct of Aegion’s business between signing and closing of the merger agreement and the provisions of the merger agreement relating to 2021 employee compensation matters and New Mountain’s commitment to retain certain employee benefits in effect for 18 months following the closing. Representatives of Centerview Partners reviewed with the Board Centerview Partners’ financial analysis of the merger consideration and rendered to the Board an oral opinion, which was subsequently confirmed by delivery of a written opinion dated February 15, 2021 that, as of such date and based on and subject to the various assumptions made, procedures followed, matters considered and qualifications and limitations upon the review undertaken in preparing its opinion, the merger consideration to be paid to the holders of shares of Aegion common stock (other than as specified in such opinion) was fair, from a financial point of view, to such holders. Following further discussion and consideration, the Board unanimously (i) determined that the original merger agreement and the original transactions were fair to and in the best interests of Aegion and its stockholders, (ii) approved and declared advisable the original merger agreement and the original transactions, (iii) authorized and approved the execution, delivery and performance by Aegion of the original merger agreement and the consummation of the original transactions, (iv) resolved, subject to the terms of the original merger agreement, to recommend the adoption of the original merger agreement by the stockholders of Aegion and (v) directed that the original merger agreement be submitted to a vote of the stockholders of Aegion.

During the night of February 15, 2021, the parties finalized the terms of the original merger agreement and associated disclosure schedule, the equity commitment letter, the limited guarantee and the debt commitment letter. Aegion, Parent and Merger Sub executed and delivered the original merger agreement and Aegion delivered the final disclosure schedule. Parent and the New Mountain fund executed and delivered the equity commitment letter and Aegion and the New Mountain fund executed and delivered the limited guarantee. The lenders also executed and delivered the debt commitment letter.

On the morning of February 16, 2021, before the open of trading on the Nasdaq, Aegion issued a press release announcing that it had entered into the original merger agreement with Parent and Merger Sub under which Parent would acquire Aegion for $26.00 per share of Aegion common stock in cash.

On March 9, 2021, Aegion received an unsolicited, non-binding proposal from a potentially interested financial party (which we refer to as “Party D”) to acquire, together with the shareholders of a potentially interested strategic party that is a direct competitor to Aegion (which we refer to as “Party E”), 100% of the issued and outstanding common stock of Aegion for $28.00 per share of Aegion common stock in cash (which we refer to as the “Party D/E proposal”). The Party D/E proposal indicated that such acquisition would be made by a newly formed company to be jointly owned by Party D and the shareholders of Party E which would be funded through a combination of debt and equity capital and attached non-binding highly confident letters from six potential

sources of debt financing each providing for up to $635 million of debt financing. The Party D/E proposal stated that Party D would commit to supply 100% of the equity capital required for the acquisition. The Party D/E proposal included a draft of a merger agreement (which we refer to as the “proposed Party D/E merger agreement”), together with a copy of such draft marked in a manner that indicated all changes from the original merger agreement. Party D indicated that it would be willing to sign the proposed Party D/E merger agreement by approximately March 26, 2021, which period would allow for the completion of a due diligence investigation of Aegion by Parties D and E and the completion of their debt financing arrangements. The proposed Party D/E merger agreement indicated, among other things, a company termination fee of $25 million, a parent termination fee of $70 million and that Party D would be responsible for the payment of the $30 million company termination fee that would become payable by Aegion to New Mountain upon the termination of the original merger agreement (which Aegion would be obligated to reimburse in the event the merger agreement entered into with Party D and Party E was terminated under certain circumstances). The proposed Party D/E merger agreement included an outside date of 12 months following signing. The proposed Party D/E merger agreement did not include any changes to the “hell or high water” antitrust covenant requiring parent and merger sub to take any and all actions necessary to avoid or eliminate each and every impediment under any antitrust law to enable the merger to be completed, but it did not expand the situations where the parent termination fee would become payable to include a regulatory failure. The Party D/E proposal also included forms of an equity commitment letter and limited guarantee that certain affiliates of Party D would deliver in connection with signing of the proposed Party D/E merger agreement.

Later on March 9, 2021, at the instruction of Aegion, representatives of Centerview Partners notified New Mountain of the Party D/E proposal and provided New Mountain with a copy of the proposal, in accordance with the terms of the original merger agreement.

Throughout the day on March 10, 2021, representatives of New Mountain, Centerview Partners, Ropes & Gray and Shearman & Sterling had multiple conference calls during which the various parties discussed the Party D/E proposal and Aegion’s rights and obligations under the original merger agreement.

In the afternoon of March 10, 2021, representatives of Ropes & Gray, on behalf of New Mountain, sent a letter to Aegion and representatives of Shearman & Sterling asserting the speculative and conditional nature of the Party D/E proposal and arguing that, given the lack of financing, required consents and significant antitrust risk associated with the Party D/E proposal, the Board could not determine in good faith that the Party D/E proposal was, or could reasonably be expected to result in, a “Superior Proposal” or that the failure to engage in discussions or negotiations with Party D and Party E would, or would reasonably be likely to, violate the Board’s fiduciary duties. Among other things, the Ropes & Gray letter asserted that the Party D/E proposal was an uncommitted, undiligenced proposal that amounted to an attempt by a direct competitor of Aegion (Party E) to obtain access to its non-public information by proposing a transaction that had significant and material risk of failing to close.

On the evening of March 10, 2021, the Board held a special meeting, with certain members of Aegion management in attendance. Representatives of Shearman & Sterling and Centerview Partners also attended portions of that meeting. At that meeting, the attendees discussed the Party D/E proposal and Aegion’s potential responses thereto. The attendees focused in particular on several aspects of the Party D/E proposal in comparison to the terms of the original merger agreement, including the proposed parties to the transactions, the proposed price per share of Aegion common stock, the timing and resources estimated to be required for diligence, signing and closing, the increased risks to Aegion associated with an extended period to closing, the increased competitive risks to Aegion’s operations associated with Party E’s potential access to due diligence materials given it is a direct competitor to Aegion (regardless of safeguards employed), the increased risks and timing associated with antitrust review given Party E’s involvement, the increased risks associated with Aegion’s continuing operations given Party E’s involvement (which could be further exacerbated by an extended antitrust review period), the reduced present value of the offer price on a time adjusted basis and the risk associated with maintaining the proposed terms and preserving Aegion’s assets and operations through the due diligence period and through to signing of definitive agreements. During the meeting, representatives of Shearman & Sterling discussed the Board’s fiduciary duties in the context of an acquisition proposal from a third party and also reviewed with the Board Aegion’s rights and obligations under the original merger agreement. During the meeting the Board did not make a determination as to whether the Party D/E proposal could reasonably be expected to result in a “Superior Proposal” (as defined in the original merger agreement), but determined to

meet again the following day and requested that management, Shearman & Sterling and Centerview Partners develop additional information for the Board to consider at that subsequent meeting and that Centerview Partners also inform New Mountain regarding the status of the Board’s deliberations.

Following that meeting, representatives of Centerview Partners had a conference call with representatives of New Mountain during which the Centerview Partners representatives informed New Mountain that the Board had met to consider the Party D/E proposal and whether it was or could reasonably be expected to result in a “Superior Proposal.” During that call, representatives of Centerview Partners also informed New Mountain that the Board would be meeting again the next day and that, if New Mountain had any additional information it wished the Board to consider at that meeting, such information should be provided ahead of that meeting.

During the morning of March 11, 2021, representatives of Shearman & Sterling and representatives of Ropes & Gray had conference calls to discuss the Party D/E proposal, Aegion’s rights and obligations under the original merger agreement and the Board’s consideration of the Party D/E proposal, including the Board’s ongoing evaluation of whether it was or could reasonably be expected to result in a “Superior Proposal.” On those calls, representatives of Ropes & Gray reiterated their view that the Board could not determine in good faith that the Party D/E proposal was, or could reasonably be expected to result in, a “Superior Proposal” or that the failure to engage in discussions or negotiations with Party D and Party E would, or would reasonably be likely to, violate the Board’s fiduciary duties.

On the afternoon of March 11, 2021, a representative of Centerview Partners had a telephone conversation with a representative of New Mountain during which the New Mountain representative outlined the terms of a proposal to amend the original merger agreement to provide for an increase in the merger consideration to $27.00 per share of Aegion common stock in cash, an increase in the company termination fee to $70 million and an increase in the parent termination fee to $70 million. The proposal was subsequently confirmed in a conversation between representatives of Shearman & Sterling and Ropes & Gray and in an e-mail from the New Mountain representative to representatives of Centerview Partners. The e-mail also noted that New Mountain proposed to amend the equity commitment letter to increase the New Mountain fund’s equity commitment by the amount of additional aggregate merger consideration indicated by the proposal and to amend the limited guarantee to increase the New Mountain fund’s limited guarantee by the proposed $10 million incremental increase to the parent termination fee. New Mountain indicated that the proposed amendments to the original merger agreement, equity commitment letter and limited guarantee were conditioned upon a determination by the Board that the Party D/E proposal was not reasonably likely to lead to a “Superior Proposal” and further that Aegion file a preliminary proxy statement within 24 hours and reject the Party D/E proposal in the manner required by the original merger agreement. New Mountain also indicated that New Mountain’s proposal would be withdrawn if the Board determined that the Party D/E proposal was, or could reasonably be expected to result in, a “Superior Proposal” and the Board commenced discussions with Party D and Party E.

Also on the afternoon of March 11, 2021, representatives of Shearman & Sterling and Ropes & Gray participated in a conference call to discuss the terms of New Mountain’s proposal and how such proposal would need to be reflected in amendments to the original merger agreement, the equity commitment letter and the limited guarantee in the event the Board determined to proceed with New Mountain’s proposal.

On the evening of March 11, 2021, the Board held a special meeting, with certain members of Aegion management in attendance. Representatives of Shearman & Sterling and Centerview Partners also attended portions of that meeting. At that meeting, the attendees discussed the Party D/E proposal and the New Mountain proposal and Aegion’s potential responses thereto. During the meeting, representatives of Shearman & Sterling again discussed the Board’s fiduciary duties and also reviewed with the Board Aegion’s rights and obligations under the original merger agreement. In light of the new proposal from New Mountain, the Board again focused its discussions in particular on several aspects of the Party D/E proposal in comparison to the terms of New Mountain’s new proposal, including the proposed parties to the transactions, the proposed price per share of Aegion common stock, the timing and resources estimated to be required for diligence, signing and closing, the increased risks to Aegion associated with a potentially extended period to closing, the increased competitive risks to operations associated with Party E’s potential access to due diligence materials (regardless of safeguards employed), the increased risks and timing associated with antitrust review given Party E’s involvement, the increased risks associated with Aegion’s continuing operations given Party E’s involvement (which could be further exacerbated by an extended period between signing and closing), the reduced present value of the offer price on a time adjusted basis and the risk associated with maintaining the proposed terms and preserving

Aegion’s assets and operations through the due diligence period and through to signing of definitive agreements. In addition, the Board reviewed an updated presentation from Centerview Partners summarizing the Party D/E proposal and the new proposal from New Mountain, which included a time-value of money analysis. The Board made no determination with respect to the Party D/E proposal but authorized Centerview Partners to make a counter proposal to New Mountain on the same terms as included in New Mountain’s proposal received earlier that day but with a company termination fee of $40 million.

Following that meeting, representatives of Centerview Partners communicated the Board’s counter proposal to New Mountain as directed.

Also following that meeting, representatives of Shearman & Sterling and Ropes & Gray had a conference call during which Shearman & Sterling also communicated the Board’s counter proposal to Ropes & Gray.

Later in the evening on March 11, 2021, representatives of Ropes & Gray sent proposed amendments to the original merger agreement, equity commitment letter and limited guarantee to Shearman & Sterling providing for an increase in the merger consideration to $27.00 per share of Aegion common stock in cash, an increase in the company termination fee to $70 million, an increase in the parent termination fee to $70 million, an increase in the New Mountain fund’s equity commitment by the amount of additional aggregate merger consideration indicated by the amendment to the original merger agreement and an increase in the amount of the New Mountain fund’s limited guarantee by the proposed $10 million incremental increase to the parent termination fee. In subsequent email correspondence that evening with representatives of Shearman & Sterling, representatives of Ropes & Gray stated that New Mountain’s updated proposal for the company termination fee had been reduced to $55 million.

In email correspondence during the morning of March 12, 2021, representatives of Ropes & Gray confirmed to representatives of Shearman & Sterling that New Mountain’s proposal of a $70 million company termination fee had been reduced further to $50 million, which was also subsequently confirmed in email correspondence from representatives of New Mountain to representatives of Centerview Partners. Furthermore, representatives of Ropes & Gray proposed amending the definition of “Superior Proposal” in the original merger agreement to address New Mountain’s view that speed and certainty should be significant factors in the Board’s consideration of whether or not a new proposal would be superior to the original merger agreement. The New Mountain proposal remained conditioned upon a determination by the Board that the Party D/E proposal was not reasonably likely to lead to a “Superior Proposal” and rejection of the Party D/E proposal in the manner required by the original merger agreement; however, the representatives of Ropes & Gray recognized that the proposal could not require filing of the preliminary proxy statement reflecting the amended terms of the merger agreement prior to the morning of Monday, March 15, 2021.

Also on March 12, 2021, following press reports that Aegion had received a competing offer, Aegion issued a press release announcing that it had received an unsolicited, non-binding proposal.

In the afternoon on March 12, 2021, representatives of the antitrust groups within Shearman & Sterling and Ropes & Gray held a conference call in which the representatives of Ropes & Gray shared information that New Mountain had developed in connection with its analysis of the proposed transaction with Aegion and presented their view of the competitive risks presented by the inclusion of Party E in the Party D/E proposal. Both sides discussed those risks as including the possibility of a protracted antitrust review period, which could include a “second request” from the antitrust authorities (as compared to the anticipated review period of the transaction with New Mountain), which would extend the time period required before closing, and the potential that the antitrust authorities could object to and seek to prevent the transaction or otherwise require remedial measures, which could include the imposition of restraints on or require the divestiture of businesses in certain markets.

In the morning of March 13, 2021, representatives of Shearman & Sterling sent revised drafts of the amendments to the original merger agreement, equity commitment letter and limited guarantee to Ropes & Gray. In the amendment, the amount of the company termination fee was left open pending further negotiation. The amendment also contained proposed revisions to the definition of a “Superior Proposal” that was sent by Ropes & Gray on the prior evening that were designed to ensure the Board would be free to exercise its fiduciary duties in evaluating any proposal.

Later on March 13, 2021, representatives of New Mountain indicated to representatives of Centerview Partners that New Mountain was willing to agree to a $40 million company termination fee.

Also on March 13, 2021, the Board held a special meeting. In attendance for portions of the meeting were members of management and representatives of Centerview Partners and Shearman & Sterling. Members of the Board had been provided with a set of meeting materials, a financial analysis prepared by representatives of Centerview Partners, including a summary of the terms and conditions of the Party D/E proposal and the New Mountain proposal, copies of the amendments to the original merger agreement, equity commitment letter and limited guarantee and a summary of the terms and conditions of the amendment to the original merger agreement prepared by representatives of Shearman & Sterling. During that meeting, representatives of Shearman & Sterling discussed the Board’s fiduciary duties in the context of a potential acquisition of Aegion generally and specifically in the context of a competing proposal as well as Aegion’s rights and obligations under the terms of the original merger agreement in the context of an acquisition proposal. Shearman & Sterling then reviewed for the Board the terms of the proposed amendment to the original merger agreement that had been agreed with New Mountain to reflect New Mountain’s proposal. Representatives of Centerview Partners then reviewed with the Board the Party D/E proposal and the New Mountain proposal, including the further reduction of the increased company termination fee to $40 million, and the Board discussed the proposals with representatives of Centerview Partners and Shearman & Sterling. Representatives of Centerview Partners reviewed with the Board Centerview Partners’ financial analysis of the increased merger consideration included in the amendment to the original merger agreement and rendered to the Board an oral opinion, which was subsequently confirmed by delivery of a written opinion dated March 13, 2021 that, as of such date and based on and subject to the various assumptions made, procedures followed, matters considered and qualifications and limitations upon the review undertaken in preparing its opinion, the merger consideration to be paid to the holders of shares of Aegion common stock (other than as specified in such opinion) was fair, from a financial point of view, to such holders. For a more detailed discussion of Centerview Partners’ opinion, please see the section entitled “The Merger (Proposal 1)—Opinion of Aegion’s Financial Advisor” beginning on page 56 of this proxy statement. After considering those presentations and following further discussion, the Board determined that the Party D/E proposal was not, and could not be reasonably expected to result in, a “Superior Proposal”. Accordingly, the Board determined that the terms of the original merger agreement prohibited Aegion from engaging in any discussions or negotiations with Party D and Party E. Following further discussion and consideration, the Board unanimously (i) determined that the amended merger agreement and the amended transactions are fair to and in the best interests of Aegion and its stockholders, (ii) approved and declared advisable the amended merger agreement and the amended transactions, (iii) authorized and approved the execution, delivery and performance by Aegion of the amendment to the merger agreement and the consummation of the amended transactions, (iv) resolved, subject to the terms of the amended merger agreement, to recommend the adoption of the amended merger agreement by the stockholders of Aegion and (v) directed that the amended merger agreement be submitted to a vote of the stockholders of Aegion.

Following that meeting, the parties finalized the amendments to the original merger agreement, the equity commitment letter and the limited guarantee. Aegion, Parent and Merger Sub executed and delivered the amendment to the merger agreement, Parent and the New Mountain fund executed and delivered the amendment to the equity commitment letter and the New Mountain fund executed and delivered the amendment to the limited guarantee.

On the morning of March 15, 2021, before the open of trading on the Nasdaq, Aegion issued a press release announcing that it had negotiated an amendment to the original merger agreement and executed the amended merger agreement under which Parent would acquire Aegion for $27.00 per share of Aegion common stock in cash and pursuant to which the parties had agreed to a $70 million parent termination fee and a $40 million company termination fee.

During the morning of March 17, 2021, a representative of Centerview Partners received a call from a representative of Party D who indicated that Party D would be submitting another non-binding proposal for the acquisition of Aegion.

Later in the morning of March 17, 2021, Aegion received a revised unsolicited, non-binding proposal from Party D to acquire 100% of the issued and outstanding common stock of Aegion for $28.50 per share of Aegion common stock in cash (which we refer to as the “Party D proposal”). The Party D proposal indicated that such acquisition would be made by a newly formed company to be wholly owned by Party D, that Party D would be the sole acquiror of Aegion and that Party D was not proposing to acquire Aegion jointly with Party E. The Party D proposal also stated that definitive transaction documents would not contain any conditionality as to the

arrangements between Party D and Party E and that Party D’s proposed acquisition of Aegion would be funded through a combination of debt and equity capital, with Party D to supply 100% of the equity capital required for the acquisition, and attached the same non-binding highly confident letters from six potential sources of debt financing each providing for up to $635 million of debt financing as were attached to the Party D/E proposal. The Party D proposal also included a draft of a merger agreement (which we refer to as the “proposed Party D merger agreement”), together with a copy of such draft marked in a manner that indicated all changes from the original merger agreement. Party D indicated that it would be willing to sign the proposed Party D merger agreement on or about the fourteenth day from being granted access to due diligence information that would allow Party D to confirm the terms of the Party D proposal, without specifying what due diligence information would be required. The proposed Party D merger agreement indicated, among other things, a company termination fee of $30 million, a parent termination fee of $70 million and that Party D would be responsible for the payment of the $40 million company termination fee that would become payable by Aegion to New Mountain upon the termination of the amended merger agreement (which Aegion would be obligated to reimburse in the event the merger agreement entered into with Party D was terminated under certain circumstances). The proposed Party D merger agreement contained the same outside date of August 16, 2021 as set forth in the amended merger agreement, but provided that closing under the proposed Party D merger agreement could be consummated prior to April 16, 2021 (as compared to the closing of the merger which, in accordance with the amended merger agreement, cannot be consummated prior to April 16, 2021 unless Aegion and New Mountain agree otherwise). The proposed Party D merger agreement did not include any changes to the “hell or high water” antitrust covenant requiring parent and merger sub to take any and all actions necessary to avoid or eliminate each and every impediment under any antitrust law to enable the merger to be completed and did not expand the situations where the parent termination fee would become payable to include a regulatory failure, however the proposed Party D merger agreement did provide that none of Party D nor any of its affiliates would file a notification and report form pursuant to the HSR Act with respect to Party D’s anticipated transaction with Party E earlier than five business days following the closing date under the Party D merger agreement. The Party D proposal also included forms of an equity commitment letter and limited guarantee that certain affiliates of Party D would deliver in connection with signing of the proposed Party D merger agreement.

Also on the morning of March 17, 2021, at the instruction of Aegion, representatives of Centerview Partners notified New Mountain of the Party D proposal and provided New Mountain with a copy of the proposal, in accordance with the terms of the merger agreement.

In the morning of March 18, 2021, representatives of Ropes & Gray, on behalf of New Mountain, sent a letter to Aegion and representatives of Shearman & Sterling asserting the speculative and conditional nature of the Party D proposal and arguing that, given the quantum of the change in price compared to the price offered in the Party D/E proposal, the lack of committed financing, the due diligence required to be conducted by Party D and the potential uncertainty and delay created by any subsequent transaction between Party D and Party E, the Party D proposal was not a “bona fide” proposal, as is required by the definition of “Superior Proposal.” Among other things, the letter from Ropes & Gray asserted that the Party D proposal was an uncommitted, undiligenced proposal that amounted to another attempt by Party D to disrupt Aegion’s business operations and interfere with the consummation of the transaction through iterative, illusory proposals that are not likely to be consummated in accordance with their terms. The letter also provided that New Mountain would be willing to consider a limited waiver of the no-solicitation provisions of the merger agreement to allow the Board time to ask questions and discuss with Party D how Party D proposed to address the risks and uncertainties associated with its proposal, but that such waiver would not permit Aegion to enter into any confidentiality agreement, or share any non-public information, with Party D.

During the afternoon of March 18, 2021, the Board held a special meeting, with certain members of Aegion management and representatives of Shearman & Sterling and Centerview Partners in attendance. Members of the Board had been provided with a set of meeting materials, including summaries of the terms and conditions of the Party D Proposal, prepared by representatives of Centerview Partners and representatives of Shearman & Sterling. At that meeting, the attendees discussed the Party D proposal and Aegion’s potential responses thereto. The attendees focused in particular on several aspects of the Party D proposal and the terms of the merger agreement attached thereto in comparison to the terms of the Party D/E proposal and the terms of the merger agreements attached thereto, including the proposed parties to the transactions and the fact that Party D had removed Party E from the pre-closing transaction structure, the increase in the proposed price per share of Aegion common stock, the reduced timing and resources estimated to be required for diligence, signing and

closing, the reduced regulatory risks and the reduced competitive risks to Aegion’s operations as a result of Party D’s removal of Party E from the pre-closing transaction structure, the possible reduced risks and timing associated with antitrust review given Party D’s removal of Party E from the pre-closing transaction structure, the possible reduced risks associated with Aegion’s continuing operations given Party D’s removal of Party E from the pre-closing transaction structure and the risk associated with maintaining the proposed terms and preserving Aegion’s assets and operations through the due diligence period and through to signing of definitive agreements. During the meeting, representatives of Shearman & Sterling discussed the Board’s fiduciary duties in the context of an acquisition proposal from a third party and also reviewed with the Board Aegion’s rights and obligations under the amended merger agreement, including the revised definition of “Superior Proposal.” During the meeting the Board did not make a determination as to whether the Party D proposal could reasonably be expected to result in a “Superior Proposal”, but authorized that management, with the assistance of Shearman & Sterling and Centerview Partners, negotiate and execute a limited waiver of the no-solicitation provisions of the merger agreement to be signed by Parent to allow the Board time to ask questions and consider how Party D proposed to address the risks and uncertainties associated with its proposal, as suggested by Ropes & Gray, on behalf of New Mountain, in its letter dated March 18, 2021.

During the evening of March 18, 2021, as directed by the Board, representatives of Shearman & Sterling sent a draft of such limited waiver to representatives of Ropes & Gray.

During the morning of March 19, 2021, Parent executed a version of the limited waiver in substantially the same form as provided by representatives of Shearman & Sterling on March 18, 2021.

During the afternoon of March 19, 2021, representatives of Centerview Partners sent a list of clarification questions to representatives of Party D with respect to the Party D proposal.

During the morning of March 20, 2021, certain members of Aegion management and representatives of Shearman & Sterling and Centerview Partners had a conference call with certain representatives of Party D and Party D’s legal and financial advisors to discuss the clarification questions with respect to the Party D proposal that had been shared with representatives of Party D on March 19, 2021. During that call, the attendees discussed matters related to confidentiality, Party D’s relationship with Party E and Party D’s intentions with respect to a post-closing transaction with Party E, the key financial assumptions underlying the Party D proposal, the scope of due diligence that Party D would be seeking to conduct should the Board determine that the Party D proposal was, or could reasonably be expected to result in, a “Superior Proposal” (as defined in the amended merger agreement), the basis for Party D’s belief that the Party D proposal had very little antitrust and regulatory risk, the financing that was being proposed by Party D in connection with the Party D proposal and Party D’s intentions for minimizing any operational risks to Aegion in the event Party D and Aegion were to enter into a definitive agreement with respect to the Party D proposal.

On March 21, 2021, the Board held a special meeting, with certain members of Aegion management in attendance. Representatives of Centerview Partners and Shearman & Sterling were also in attendance for part of that meeting. At that meeting, the attendees discussed the Party D proposal and Aegion’s potential responses thereto, and Aegion management, representatives of Shearman & Sterling and representatives of Centerview Partners provided an update to, and discussed with, the Board the feedback and clarifications received from Party D during the conference call on March 20, 2021. During those discussions, the attendees focused in particular on several aspects of the Party D proposal in comparison to the terms of the amended merger agreement, including the proposed parties to the transactions, the proposed price per share of Aegion common stock and the timing and resources estimated to be required for diligence, signing and closing, the fact that the Party D proposal did not include Party E and did not contain any conditionality as to the arrangements between Party D and Party E, as well as the risk associated with maintaining the proposed terms of the Party D proposal and preserving Aegion’s assets and operations through the due diligence period and through to signing of definitive agreements. During the meeting, representatives of Shearman & Sterling also discussed the Board’s fiduciary duties in the context of an acquisition proposal from a third party and also reviewed with the Board Aegion’s rights and obligations under the amended merger agreement. During the meeting the Board determined that the Party D proposal could reasonably be expected to result in a “Superior Proposal” (as defined in the amended merger agreement) and authorized Aegion management, with the assistance of Shearman & Sterling and Centerview Partners, to negotiate and execute an “Acceptable Confidentiality Agreement” (as defined in the amended merger agreement) with Party D, as well as a clean team agreement to facilitate the sharing of commercially and

competitively sensitive information on an advisor-only basis, provide Party D with access to certain due diligence information pursuant to such confidentiality agreement and negotiate the terms of the proposed Party D merger agreement with Party D. The Board also instructed Aegion management to report back to the Board when there was a firm offer from Party D for the Board to consider.

Following that meeting, representatives of Shearman & Sterling sent a draft confidentiality agreement and a draft clean team agreement to representatives of Party D’s outside counsel which, in the case of the draft confidentiality agreement, was drafted to constitute an “Acceptable Confidentiality Agreement” (as defined in the amended merger agreement) and was proposed to be entered into between Aegion and Party D. The draft clean team agreement provided that certain of Aegion’s commercially and competitively sensitive information would only be provided to a restricted group of certain representatives of Party D’s advisors and would be subject to heightened confidentiality obligations. Shearman & Sterling also sent a draft confidentiality agreement to Party D’s legal counsel proposed to be entered into between Aegion and Party E to require that Party E maintain confidentiality over information regarding the potential transaction between Aegion and Party D that it had received or may receive from Party D.

Later in the evening of March 21, 2021, Aegion executed confidentiality agreements with Party D and Party E in substantially the same forms as the drafts that Shearman & Sterling had provided to Party D’s legal counsel earlier that evening.

During the morning of March 22, 2021, Aegion issued a press release announcing that it had received an unsolicited, non-binding proposal for the acquisition of all of the outstanding shares of Aegion at $28.50 per share of Aegion common stock, that the Board had determined that such proposal could reasonably be expected to result in a “Superior Proposal” (as defined in the amended merger agreement) and that there could be no assurances that such proposal would result in a “Superior Proposal” or that the terms of any transaction resulting from such proposal would be the same as set forth in the proposal.

Later on March 22, 2021, representatives of Party D were provided with access to a data room containing certain due diligence information that had previously been provided to New Mountain, excluding certain commercially and competitively sensitive information.

On March 23, 2021, Aegion and Party D executed a clean team agreement in substantially the same form as the draft that Shearman & Sterling had provided to Party D’s legal counsel on March 21, 2021, to facilitate the sharing of commercially and competitively sensitive information on an advisor-only basis. Following execution of that clean team agreement, certain representatives of certain of Party D’s advisors were provided with access to a separate data room containing certain of Aegion’s commercially and competitively sensitive due diligence information.

As of the filing date of this proxy statement, Party D had not yet completed its review of the due diligence information with which it had been provided access and on which the terms of the Party D proposal was conditioned, nor has Party D completed the financing arrangements contemplated by the Party D proposal. As of the filing date of this proxy statement, the Board has not made a determination as to whether the Party D proposal is a “Superior Proposal” that would give rise to a right in favor of Aegion to terminate the amended merger agreement in order to enter into a definitive agreement with respect to the Party D proposal, subject to observation of New Mountain’s right under the amended merger agreement to further amend the amended merger agreement such that the Party D proposal (or any revised proposal arising therefrom) would no longer be a “Superior Proposal.”

The Party D proposal is a developing situation and we will update this proxy statement before the vote is taken at the special meeting. We are sending this proxy statement to you now in order to prevent delay, and minimize the risk of the occurrence of a material adverse effect or other impediment prior to closing, assuming that the amended transactions with New Mountain will continue to represent the best transaction available to the Company following the completion of Party D’s due diligence process. However, the Company cannot predict the outcome of Party D’s due diligence process, whether the Party D proposal will become a “Superior Proposal”, the results of any negotiations with Party D or New Mountain that may follow such proposal or whether the Company will receive any other proposal from Party D, New Mountain or any other prospective acquiror.

After considering the various factors described below, the Board unanimously (i) determined that the merger agreement and the transactions are fair to and in the best interests of Aegion and Aegion’s stockholders, (ii) approved and declared advisable the merger agreement and the transactions, (iii) authorized and approved the execution, delivery and performance by Aegion of the merger agreement and the consummation of the transactions upon the terms and subject to the conditions set forth therein, (iv) resolved, subject to the terms of the merger agreement, to recommend the adoption of the merger agreement by the stockholders of Aegion and (v) directed that the merger agreement be submitted to a vote of the stockholders of Aegion.

The Board unanimously recommends that you vote (i) “FOR” the proposal to adopt the merger agreement, (ii) “FOR” the proposal to approve, on a non-binding advisory basis, specified compensation that may be paid or become payable to Aegion’s named executive officers in connection with the merger and contemplated by the merger agreement and (iii) “FOR” the proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement.

In recommending that stockholders vote in favor of the proposal to adopt the merger agreement, the Board considered a number of factors, including, but not limited to, the following (not necessarily in order of relative importance):

The Board also considered a number of uncertainties and risks concerning the merger, including the following:

The foregoing discussion is not meant to be exhaustive, but summarizes the material factors considered by the Board in its consideration of the merger. After considering these and other factors, the Board concluded that the potential benefits of the merger outweighed the uncertainties and risks. In view of the variety of factors considered by the Board and the complexity of these factors, the 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 Board applied his or her own personal business judgment to the strategic alternatives process and may have assigned different weights to different factors. Based upon the totality of the information presented to and considered by the Board, the Board unanimously approved the merger agreement and the consummation of the merger in accordance with the terms and subject to the conditions of the merger agreement and recommends that Aegion’s stockholders adopt the merger agreement.

On March 13, 2021, Centerview rendered to the Board its oral opinion, subsequently confirmed in a written opinion dated such date, that, as of such date and based upon and subject to various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, the merger consideration to be paid to the holders of shares (other than excluded shares) pursuant to the merger agreement was fair, from a financial point of view, to such holders.

The full text of Centerview’s written opinion, dated March 13, 2021, which describes the assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, is attached as Annex C and is incorporated herein by reference. The summary of the written opinion of Centerview set forth below is qualified in its entirety to the full text of Centerview’s written opinion attached as Annex C. Centerview’s financial advisory services and opinion were provided for the information and assistance of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the transaction and Centerview’s opinion only addressed the fairness, from a financial point of view, as of the date thereof, to the holders of shares (other than excluded shares) of the merger consideration to be paid to such holders pursuant to the merger agreement. Centerview’s opinion did not address any other term or aspect of the merger agreement or the transaction and does not constitute a recommendation to any stockholder of the Company or any other person as to how such stockholder or other person should vote with respect to the merger or otherwise act with respect to the transaction or any other matter.

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

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

Centerview also participated in discussions with members of the senior management and representatives of the Company regarding their assessment of the internal data. In addition, Centerview reviewed publicly available financial and stock market data, including valuation multiples, for the Company and compared that data with similar data for certain other companies, the securities of which are publicly traded, in lines of business that Centerview deemed relevant. Centerview also compared certain of the proposed financial terms of the transaction with the financial terms, to the extent publicly available, of certain other transactions that Centerview deemed relevant, and conducted such other financial studies and analyses and took into account such other information as Centerview deemed appropriate.

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

Centerview’s opinion expressed no view as to, and did not address, the Company’s underlying business decision to proceed with or effect the transaction, or the relative merits of the transaction as compared to any alternative business strategies or transactions that might be available to the Company or in which the Company might engage. Centerview’s opinion was limited to and addressed only the fairness, from a financial point of view, as of the date of Centerview’s written opinion, to the holders of the shares (other than excluded shares) of the merger consideration to be paid to such holders pursuant to the merger agreement. For purposes of its opinion,

Centerview was not asked to, and Centerview did not, express any view on, and its opinion did not address, any other term or aspect of the merger agreement or the transaction, including, without limitation, the structure or form of the transaction, or any other agreements or arrangements contemplated by the merger agreement or entered into in connection with or otherwise contemplated by the transaction, including, without limitation, the fairness of the transaction or any other term or aspect of the transaction to, or any consideration to be received in connection therewith by, or the impact of the transaction on, the holders of any other class of securities, creditors or other constituencies of the Company or any other party. In addition, Centerview expressed no view or opinion as to the fairness (financial or otherwise) of the amount, nature or any other aspect of any compensation to be paid or payable to any of the officers, directors or employees of the Company or any party, or class of such persons in connection with the transaction, whether relative to the merger consideration to be paid to the holders of the shares (other than excluded shares) pursuant to the merger agreement or otherwise. Centerview’s opinion was necessarily based on financial, economic, monetary, currency, market and other conditions and circumstances as in effect on, and the information made available to Centerview as of, the date of Centerview’s written opinion, and Centerview does not have any obligation or responsibility to update, revise or reaffirm its opinion based on circumstances, developments or events occurring after the date of Centerview’ written opinion. Centerview’s opinion does not constitute a recommendation to any stockholder of the Company or any other person as to how such stockholder or other person should vote with respect to the merger or otherwise act with respect to the transaction or any other matter. Centerview’s financial advisory services and its written opinion were provided for the information and assistance of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the transaction. The issuance of Centerview’s opinion was approved by the Centerview Partners LLC Fairness Opinion Committee.

The following is a summary of the material financial analyses prepared and reviewed with the Board in connection with Centerview’s opinion, dated March 13, 2021. The summary set forth below does not purport to be a complete description of the financial analyses performed or factors considered by, and underlying the opinion of, Centerview, nor does the order of the financial analyses described represent the relative importance or weight given to those financial analyses by Centerview. Centerview may have deemed various assumptions more or less probable than other assumptions, so the reference ranges resulting from any particular portion of the analyses summarized below should not be taken to be Centerview’s view of the actual value of the Company. Some of the summaries of the financial analyses set forth below include information presented in tabular format. In order to fully understand the financial analyses, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses performed by Centerview. Considering the data in the tables below without considering all financial analyses or factors or the full narrative description of such analyses or factors, including the methodologies and assumptions underlying such analyses or factors, could create a misleading or incomplete view of the processes underlying Centerview’s financial analyses and its opinion. In performing its analyses, Centerview made numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of the Company or any other parties to the transaction. None of the Company, Parent, Merger Sub or Centerview or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of the Company do not purport to be appraisals or reflect the prices at which the Company may actually be sold. Accordingly, the assumptions and estimates used in, and the results derived from, the financial analyses are inherently subject to substantial uncertainty. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before March 12, 2021 (the last trading day before the public announcement of the transaction) and is not necessarily indicative of current market conditions. The implied per share equity value ranges described below were based on approximately 31.9 million fully-diluted shares of common stock (determined using the treasury stock method and taking into account outstanding restricted stock units, performance stock units and deferred stock units) outstanding as of February 12, 2021, based on information provided by the Company.

Centerview reviewed certain financial information of the Company and compared it to corresponding financial information of certain publicly traded companies (nine (9) in total) that Centerview selected, based on its

experience and professional judgment (which are referred to as the “selected companies” in this summary of Centerview's opinion). Although none of the selected companies is directly comparable to the Company, the companies listed below were chosen by Centerview because, among other reasons, they are publicly traded companies with certain operational, business and/or financial characteristics that, for purposes of Centerview’s analysis, may be considered similar to those of the Company.

However, because none of the selected companies is exactly the same as the Company, Centerview believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected public company analysis. Accordingly, Centerview also made qualitative judgments, based on its experience and professional judgment, concerning differences between the operational, business and/or financial characteristics of the Company and the selected companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis.

Using publicly available information obtained from SEC filings and other data sources as of March 12, 2021, Centerview calculated, for each selected company, among other things, such company’s enterprise value (calculated as the equity value (determined using the treasury stock method and taking into account outstanding in-the-money options, warrants, restricted stock units, performance stock units, deferred stock units and other convertible securities) plus the value of debt and certain liabilities, less cash and cash equivalents), as a multiple of Wall Street research analyst consensus estimated earnings before interest, taxes, depreciation and amortization, commonly referred to as EBITDA, for calendar year 2021. Such multiple is referred to, with respect to the selected companies, as the “2021 EV/Estimated EBITDA Multiple.”

The selected companies are summarized below:

Based on its analysis and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a reference range of 2021 EV/Estimated EBITDA Multiples of 9.5x to 12.0x. In selecting this range of 2021 EV/Estimated EBITDA Multiples, Centerview made qualitative judgments based on its experience and professional judgment concerning differences between the business, financial and operating characteristics of the Company and the selected companies that could affect their public trading values in order to provide a context in which to consider the results of the quantitative analysis.

Centerview applied this range of 2021 EV/Estimated EBITDA Multiples to (i) the Company’s estimated calendar year 2021 EBITDA as set forth in the projections included in the internal data and (ii) Wall Street research analyst consensus estimated EBITDA of the Company for calendar year 2021, in each case, to derive a range of implied enterprise values for the Company. Centerview subtracted from both these ranges of implied enterprise values the Company's net debt of approximately $134 million as of December 31, 2020, to derive a range of implied equity values for the Company in each case. Centerview then divided these implied equity values by the number of fully-diluted shares of Company common stock as set forth in the internal data to derive a range of implied values per share of Company common stock of (i) based on the Company’s estimated calendar year 2021 EBITDA as set forth in the projections, $26.90 to $35.10 and (ii) based on Wall Street research analyst consensus

EBITDA of the Company for calendar year 2021, $25.40 to $33.20, in each case, rounded to the nearest $0.05. Centerview compared both of these ranges to the $27.00 per share in cash, without interest, proposed to be paid to the holders of shares (other than excluded shares) pursuant to the merger agreement.

Centerview reviewed and compared certain information relating to the following selected transactions that Centerview, based on its experience and professional judgment (which are referred to as the “selected transactions” in this summary of Centerview’s opinion), deemed relevant to consider in relation to the Company and the merger.

However, because none of the selected transactions used in this analysis is identical or directly comparable to the merger, Centerview believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected transaction analysis. Accordingly, Centerview also made qualitative judgments, based on its experience and professional judgment, concerning differences between the operational, business or financial characteristics of the Company and each target company as well as the merger and the selected transactions that could affect the transaction values of each in order to provide a context in which to consider the results of the quantitative analysis. Although none of the selected transactions is directly comparable to the merger, the selected transactions listed below were selected, among other reasons, based on Centerview’s experience and professional judgment, because the selected transactions have certain characteristics that, for the purposes of this analysis, may be considered similar to certain characteristics of the merger. The reasons for and the circumstances surrounding each of the selected transactions analyzed were diverse and there are inherent differences in the business, operations, financial conditions and prospects of the Company and the target companies included in the selected transactions analysis.

Using publicly available information obtained from SEC filings and other data sources, Centerview calculated, for each selected transaction, among other things, the enterprise value implied for the applicable target company based on the consideration payable in the applicable selected transaction, as a multiple of the target company’s EBITDA for the last 12-month period (which is referred to as “LTM”), for which financial information had been made public at the time of the announcement of such transactions. Such multiple is referred to, with respect to the selected transaction, as the “EV/LTM EBITDA Multiple”.

The selected transactions considered in this analysis are summarized below:

Based on its analysis of the relevant metrics for each of the target companies in the selected transactions and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a reference range of EV/LTM adjusted EBITDA Multiples of 8.0x to 10.5x. In selecting this reference range, Centerview made qualitative judgments based on its experience and professional judgment concerning

differences between the business, financial and operating characteristics and prospects of the Company and the target companies included in the selected transactions and other factors that could affect the public trading, acquisition or other values of such companies or the Company.

Centerview applied this reference range to the Company’s LTM EBITDA as of December 31, 2020 to derive a range of implied enterprise values for the Company. Centerview subtracted from this range of implied enterprise values the Company's net debt of approximately $134 million as of December 31, 2020, to derive a range of implied equity values for the Company. Centerview then divided these implied equity values by the number of fully-diluted shares of Company common stock as set forth in the internal data to derive a range of implied values per share of common stock of $18.50 to $25.60, rounded to the nearest $0.05. Centerview compared this range to the $27.00 per share in cash, without interest, proposed to be paid to the holders of Company common stock (other than excluded shares) pursuant to the merger agreement.

Centerview performed a discounted cash flow analysis of the Company based on the projections as described below under section “The Merger (Proposal 1)—Projected Financial Information” beginning on page 62 of this proxy statement and the calculations of after-tax unlevered free cash flows based thereon. A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset or set of assets by calculating the “present value” of estimated future cash flows of the asset or set of assets. “Present value” refers to the current value of future cash flows and is obtained by discounting those future cash flows by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

In performing this analysis, Centerview calculated an implied per share equity range for the shares of Company common stock by discounting to present value as of December 31, 2020 using discount rates ranging from 10.00% to 11.50% (reflecting Centerview’s analysis of the Company’s weighted average cost of capital) and the mid-year convention, the forecasted unlevered free cash flows of the Company based on the company projections during the period beginning the first quarter of 2021, and ending in December 2025. The implied terminal value of the Company at the end of the forecast period was estimated by using perpetuity growth rates ranging from 2.0% to 3.0%.

Based on its analysis, Centerview calculated a range of implied enterprise values of the Company. Centerview subtracted from this range of implied enterprise values the Company's net debt of approximately $134 million as of December 31, 2020, to derive a range of implied equity values for the Company. Centerview then divided this range of implied equity values by the number of fully-diluted outstanding shares of Company common stock as set forth in the internal data (calculated as of February 12, 2021) to derive a range of implied values of Company common stock of $21.60 to $29.70 per share, rounded to the nearest $0.05. Centerview compared this range to the $27.00 per share in cash, without interest, to be paid to the holders of Company common stock (other than excluded shares) pursuant to the merger agreement.

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

The preparation of a financial opinion is a complex analytical process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, a financial opinion is not readily susceptible to summary description. In arriving at

its opinion, Centerview did not draw, in isolation, conclusions from or with regard to any factor or analysis that it considered. Rather, Centerview made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of the analyses.

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

Centerview is a securities firm engaged directly and through affiliates and related persons in a number of investment banking, financial advisory and merchant banking activities. In the two years prior to the date of its written opinion, except for Centerview’s current engagement, Centerview has not been engaged to provide financial advisory or other services to the Company, and has not received any compensation from the Company during such period. In the two years prior to the date of its written opinion, Centerview has been engaged to provide financial advisory services to New Mountain or New Mountain’s affiliates, including in connection with the sale of 20% of Blue Yonder Holding, Inc. (formerly JDA Software) to Panasonic Corporation, and Centerview received compensation of less than $5,000,000 from New Mountain and its affiliates for such services. Centerview may provide financial advisory and other services to or with respect to the Company, Parent, New Mountain or their respective affiliates, including portfolio companies of New Mountain in the future, for which Centerview may receive compensation. Certain (i) of Centerview’s and its affiliates’ directors, officers, members and employees, or family members of such persons, (ii) of Centerview’s affiliates or related investment funds and (iii) investment funds or other persons in which any of the foregoing may have financial interests or with which they may co-invest, may at any time acquire, hold, sell or trade, in debt, equity and other securities or financial instruments (including derivatives, bank loans or other obligations) of, or investments in, the Company, Parent, New Mountain or any of their respective affiliates, including portfolio companies of New Mountain, or any other party that may be involved in the transaction.

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

In connection with Centerview’s services as the financial advisor to the Board, the Company has agreed to pay Centerview an aggregate fee of approximately $19,200,000, $2,500,000 of which was payable upon the rendering of Centerview’s opinion in connection with the original merger agreement and the remainder of which is payable contingent upon consummation of the transaction. In addition, the Company has agreed to reimburse certain of Centerview’s expenses arising, and to indemnify Centerview against certain liabilities that may arise, out of Centerview’s engagement.

Aegion does not, on a routine basis, publicly disclose long-term projections as to future financial performance due to, among other reasons, the unpredictability of the underlying assumptions and estimates, though Aegion has in the past provided investors with full-fiscal year financial guidance on certain financial metrics, including total revenue, adjusted earnings per share and adjusted free cash flow, which are updated when necessary during the relevant fiscal year. However, in connection with the evaluation of the proposed merger, in January 2021, Aegion’s senior management shared certain non-public, unaudited prospective financial information prepared by Aegion’s senior management for strategic planning purposes with the Board, Centerview and Parent, for the five (5) fiscal years ending December 31, 2025, which we refer to as the “projections.” The projections were provided to Centerview for Centerview’s use and reliance in connection with its financial analyses and opinion described in the section entitled “The Merger (Proposal 1)—Opinion of Aegion’s Financial Advisor” beginning on page 56 of this proxy statement.

The projections were not prepared with a view to public disclosure and are included in this proxy statement only because such information was made available to the Board, Centerview and Parent in connection with the proposed merger. The projections were not prepared with a view to compliance with generally accepted

accounting principles as applied in the United States (which we refer to as “GAAP”), the published guidelines of the SEC regarding projections and forward-looking statements or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. The prospective financial information included in this document has been prepared by, and is the responsibility of, Aegion’s management, and is subjective in many respects. Furthermore, neither Aegion’s independent auditors nor any other independent accountants have audited, reviewed, examined, compiled or applied agreed-upon procedures with respect to the accompanying prospective financial information and, accordingly, assume no responsibility for, and express no opinion or other form of assurance on, such information or its achievability.

The projections are forward-looking statements. Although summaries of the projections are presented with numerical specificity, the projections reflect numerous assumptions and estimates as to future events made by Aegion’s senior management, which it believes were reasonable at the time the projections were prepared, taking into account the relevant information available to management at such time. However, the projections are not fact and should not be relied upon as being necessarily predictive of actual future results. Important factors may affect actual results and cause the forecasts not to be achieved. These factors include general economic conditions, accuracy of certain accounting assumptions, timing of business investments by Aegion, changes in actual or projected cash flows, competitive pressures, changes in tax or other laws or regulations, and the other factors described in the section entitled “Forward-Looking Statements” beginning on page 22 of this proxy statement. In addition, the projections do not take into account any circumstances or events occurring after the date that the projections were prepared and do not give effect to the merger. As a result, there can be no assurance that the projections will be realized, and actual results may be materially better or worse than those contained in the projections. The inclusion of this information should not be regarded as an indication that the Board, Aegion’s senior management team, Centerview, Parent or any other recipient of this information considered, or now considers, the projections to be material information of Aegion, or necessarily predictive of actual future results, nor should it be construed as financial guidance, and it should not be relied upon as such. The summary of the projections is not included in this proxy statement in order to influence the voting decision of any stockholder with respect to the proposal to adopt the merger agreement or any of the other proposals to be voted on at the special meeting or to influence any stockholder to make any investment decision with respect to the merger, including whether or not to seek appraisal rights with respect to the shares of Aegion’s common stock.

The projections should be evaluated, if at all, in conjunction with the historical financial statements and other information regarding Aegion contained in Aegion’s public filings with the SEC. The projections were reviewed by Aegion’s senior management with, and considered by, the Board in connection with its evaluation and approval of the merger.

Except to the extent required by applicable federal securities laws, we expressly disclaim any responsibility to update or otherwise revise the projections to reflect circumstances existing after the date when we prepared the projections or to reflect the occurrence of future events or changes in general economic or industry conditions, even in the event that any of the assumptions underlying the projections are shown to be in error. We have not done so and do not intend to do so. We can give no assurance that, had our projections been prepared either as of the date of the merger agreement or as of the date of this proxy statement, similar estimates and assumptions would be used. Neither Aegion nor any of its affiliates, directors, officers, advisors or other representatives has made or makes any representation to any of our stockholders or any other person regarding the ultimate performance of Aegion compared to the information contained in our projections or that our projections will be achieved.

In light of the foregoing factors and the uncertainties inherent in the projections and considering that the special meeting will be held several months after the projections were prepared, stockholders are cautioned not to rely on the projections included in this proxy statement.

Certain of the measures included in the projections may be considered non-GAAP financial measures, as noted below. These non-GAAP financial measures are useful to investors and management in understanding current profitability levels and liquidity that may serve as a basis for evaluating future performance and facilitating comparability of results. In addition, certain non-GAAP financial measures are a component of Aegion’s annual employee incentive plans. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in compliance with GAAP, and non-GAAP financial measures as used by Aegion may not be comparable to similarly titled amounts used by other companies. The non-GAAP

financial measures used in the projections were relied upon by Centerview for purposes of their respective financial analyses and opinion and by the Board in connection with its consideration of the merger. Financial measures provided to a financial advisor are excluded from the definition of non-GAAP financial measures and, therefore, are 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 relied upon by Centerview for purposes of their respective financial analyses and opinion or by the Board in connection with its consideration of the merger.

The following is a summary of the projections prepared by senior management of Aegion and given to the Board, Centerview, and Parent prior to the execution of the merger agreement:

In considering the recommendation by the Board that stockholders vote to adopt the merger agreement, stockholders should be aware that the directors and executive officers of Aegion have certain interests in the transaction that may be different from, or in addition to, the interests of Aegion stockholders generally. The members of the Board were aware of these interests and considered the interests of other directors, among other things, in evaluating the merger agreement and the transaction and in recommending that Aegion stockholders adopt the merger agreement.

At the effective time, each deferred stock unit that is outstanding as of immediately prior to the effective time will become fully vested (to the extent unvested) as of immediately before the effective time.

At the effective time, each outstanding performance stock unit will become fully vested (to the extent unvested) as to the greater of the number of performance stock units that would vest based on target or actual performance, in each case as of immediately prior to the effective time.

At the effective time, each outstanding restricted stock unit subject to service-based restrictions that is outstanding as of immediately prior to the effective time will become fully vested (to the extent unvested).

At the effective time, each Aegion stock unit will be cancelled and each holder thereof will receive from the surviving corporation an amount in cash, without interest, equal to the product of the number of shares of Aegion common stock underlying each Aegion stock unit (taking into account the vestings described above) multiplied by $27.00, without interest and subject to withholding.

The following table shows, as of March 31, 2021, with respect to Aegion’s directors and named executive officers (as identified in Aegion’s annual report on Form 10-K filed with the SEC on March 10, 2021) (a) the number of shares of Aegion common stock underlying each outstanding (1) deferred stock unit, (2) performance stock unit, and (3) restricted stock unit, and (b) the expected aggregate value of such Aegion stock units assuming a stock price of $27.00 per share.

See the section entitled “Advisory Vote on Specified Compensation (Proposal 2)” beginning on page 96 of this proxy statement for information regarding unvested equity compensation awards for the named executive officers in accordance with Item 402(t) of the SEC’s Regulation S-K based on the assumptions described in such section, including the assumption that the effective time occurs on March 31, 2021, and that the price per share of Aegion common stock is $27.00.

Pursuant to Aegion’s Voluntary Deferred Compensation Plan, executive officers may choose to defer up to specified maximum amounts of compensation by contributing those amounts. The plan allows for base salary deferral up to 75% of base salary, and bonus deferral of up to 100% of annual bonus amounts. Under the plan, Aegion matches contributions equal to the first 3% of compensation at a 100% rate, and contributions equal to the next 2% of compensation at a 50% rate, when aggregated with any matching contributions made under our 401(k) Profit Sharing Plan. Deferred account balances in the plan are adjusted to match the performance of participant-selected indices, which mirror fund choices available under our 401(k) Profit Sharing Plan. In connection with this plan, Aegion established a rabbi trust to fund Aegion’s promise to pay deferred

compensation obligations under the plan. This trust becomes fully funded upon a change in control. The plan was amended effective January 1, 2018, to include non-employee directors as eligible participants with respect to the cash component of the compensation paid to our non-employee directors, except that non-employee directors are not eligible for the Aegion contribution match.

Account balances will accrue for each participant based on the amount of the participant’s deferrals into the account, Aegion’s matching payment, if any, and the investment performance of the participant’s selected indices. Participants are at all times 100% vested in their deferrals, Aegion-matching payments and investment earnings.

Pursuant to the plan termination of Aegion’s Voluntary Deferred Compensation Plan in connection with the merger, each participant in the deferred compensation plan will receive a single lump sum payment in respect of his or her notional account balance within 45 days of the effective time.

Each of Mr. Morris, Ms. Germany Ballintyn, and Mr. Menghini are current participants under Aegion’s Voluntary Deferred Compensation Plan, and as a result, will be entitled to a single lump sum payment for the cash out of their notional account balances. As of March 31, 2021, each had the following account balance: Ms. Germany Ballintyn, $342,813; Mr. Morris, $1,738,978; and Mr. Menghini, $341,082.

Aegion has entered into Change in Control Agreements (the “change in control agreements”) with each of Aegion’s executive officers – Messrs. Gordon, Morris, Menghini, Heggemann and Young.

Each of the change in control agreements provide for “double trigger” payments, such that benefits are only payable if the executive is involuntarily terminated without cause or resigns with good reason within 24 months following the change in control (a “covered termination”). Upon such a covered termination, the change in control agreements provide, among other things, for the following benefits:

Under each change in control agreement, “cause” is determined solely by the board in its exercise of good faith and reasonable judgment, and it means the occurrence of any one or more of the following: (a) the breach of any employment, confidentiality, noncompete, non-solicitation or other agreement with Aegion or written Aegion policy relating to compliance with laws during the course of the executive’s employment; (b) causing, inducing, requesting or advising, or attempting to cause, induce, request or advise, any employee, representative, consultant or other similar person to terminate their relationship, or breach any agreement, with Aegion; (c) causing, inducing, requesting or advising, or attempting to cause, induce, request or advise, any customer, supplier or other Aegion business contact to withdraw, curtail or cancel its business with Aegion; (d) the executive’s willful and continued failure to substantially perform their duties with Aegion (other than failures resulting from the executive’s disability), after a written demand for substantial performance is delivered to the executive that specifically identifies the manner in which the board believes that the executive has not substantially performed their duties, and the executive fails to remedy the situation within 15 business days of receiving such written notice from Aegion; (e) the executive’s conviction of a felony; or (f) the executive’s willful engagement in conduct that is demonstrably and materially injurious to Aegion, monetarily

or otherwise. Under this standard, no act or failure to act on the executive’s part will be deemed “willful” unless done, or omitted to be done, by the executive not in good faith and without reasonable belief that the action or omission was in Aegion’s best interest.

Under each change in control agreement, “good reason” means, without the executive’s express written consent, the occurrence after a change in control of Aegion of any one or more of the following: (a) a material reduction or alteration in the nature or status of the executive’s authorities, duties or responsibilities from those that were in effect as of 90 calendar days before the change in control, other than an insubstantial and inadvertent act that is remedied by Aegion or the acquiring company promptly after receiving notice from the executive; (b) Aegion or the acquiring company requiring that the executive be based at a location more than 50 miles from the location of the executive’s principal job location or office that was in effect as of 90 calendar days before the change in control, except for required travel on Aegion’s behalf to an extent substantially consistent with the executive’s then present business travel obligations; (c) a reduction by Aegion or the acquiring company of the executive’s base salary or annual target bonus opportunity in effect as of 90 calendar days before the change in control; (d) a reduction by Aegion or the acquiring company (measured by value) of the aggregate long-term incentive opportunity provided to the executive in effect as of 90 calendar days before the change in control, or a material reduction in the aggregate employee benefits provided to the executive in effect as of 90 calendar days before the change in control; (e) the failure of Aegion to obtain a satisfactory agreement from any Aegion successor to assume and agree to perform Aegion’s obligations under the change in control agreement; and (f) Aegion’s material breach of the change in control agreement that is not cured by Aegion within 30 business days of receiving written notice of such breach from the executive.

Any severance payments made pursuant to the change in control agreements are conditioned upon the accuracy of certain representations and warranties and the executive’s performance of certain covenants and agreements, including, but not limited non-solicit and non-compete covenants for a period of 24 months post termination, perpetual confidentiality and the execution and non-revocation of a release of all claims.

In the event that the severance benefits and related payments (including the vesting of incentive awards) would be subject to the “golden parachute” excise tax under Section 4999 of the Internal Revenue Code (which we refer to as the “Code”), the executive’s payments will be either: (1) the full amount of the payments; or (2) the lesser amount that would ensure that no portion of the payments would be subject to the excise tax, whichever would put the executive in the best net after tax position, as determined by an independent auditor.

The following table shows, as of March 31, 2021, with respect to Aegion’s executive officers, the severance multiple and the value of the severance that would be payable pursuant to the change in control agreements, assuming a covered termination occurs on the closing of a merger that occurs on March 31, 2021.

In the event of a change in control, the Management Annual Incentive Plan (which we refer to as the “annual incentive plan”) provides that a pro-rata portion of the participant’s annual incentive award for 2021 will become earned, and it will be calculated using the greater of the actual performance as of the date of the change in control or the target award level (the “pro rata bonus”). Notwithstanding the pro rata bonus earned as of the

change in control, the pro rata bonus will not be paid in connection with the change in control and will instead, be paid in the ordinary course as if the change in control had not occurred (but in no event no later than February 28, 2022) or, if earlier, subject to the participant’s execution of an irrevocable release of claims, upon a termination of employment by Aegion without “cause” following a change in control, a resignation for good reason following a change in control, or a termination of employment by Aegion for poor performance following a change in control. The earned amount would be offset by any payments otherwise made under the annual incentive plan. If the executive has a covered termination in 2021 under the change in control agreements, the executive would not be eligible to receive the pro rata bonus as the pro-rata bonus payment under the change in control agreements is in lieu of any payments payable under the annual incentive plan.

See “The Merger Agreement—Other Covenants and Agreements—Indemnification and Insurance,” beginning on page 84 of this proxy statement, for a summary of the obligations of Parent and the surviving corporation with respect to insurance for and indemnification of directors and executive officers after the effective time.

See “The Merger Agreement—Other Covenants and Agreements—Employee Matters,” beginning on page 88 of this proxy statement, for a summary of certain post-closing covenants related to employee benefit arrangements.

Parent expects to finance the total amount of funds necessary to consummate the transactions, including the funds needed to pay the amounts due to Aegion’s stockholders under the merger agreement, any prepayment, repayment, refinancing or conversion of debt contemplated by the merger agreement and the debt commitment letter described below, any other amounts required to be paid in connection with the consummation of the transactions contemplated by the merger agreement, the payments required under the merger agreement in respect of Aegion’s outstanding equity awards, and any fees and expenses of or payable to Aegion or Merger Sub in connection with the transactions and the “financing” (as defined below) (collectively, with the surviving company’s and Merger Sub’s other cash on hand, we refer to such total amount as the “required amount”) primarily with (i) debt financing to be provided by certain lenders (which we refer to as the “debt financing”), and (ii) equity financing to be provided by the New Mountain fund (which we refer to as the “equity financing”, and we refer to the equity financing together with the debt financing as the “financing”), subject to terms and conditions of the commitment letters described below.

Parent has received a debt commitment letter (which refer to as the “debt commitment letter”) and a related fee letter (with customary redactions if shared with any third parties for fee amounts, pricing, other economic terms, threshold caps, pricing caps, and “market flex” related solely to economic terms), dated February 16, 2021 from Jefferies Finance LLC, Credit Suisse Loan Funding LLC of Credit Suisse AG, Deutsche Bank AG New York Branch of Deutsche Bank Securities Inc. (collectively, we refer to as these entities as the “lenders”). Under the debt commitment letter, the lenders have committed to provide up to $650,000,000 (subject to adjustment as set forth in the debt commitment letter) in debt financing for the purpose of funding a portion of the required amount. The debt commitment letter permits Parent to increase the merger consideration payable under the merger agreement provided that any increase is funded entirely by an increase in equity provided by the New Mountain fund.

Parent has received an equity commitment letter from the New Mountain fund, dated February 16, 2021 and amended March 13, 2021, pursuant to which the New Mountain fund has committed to contribute to Parent an aggregate amount of up to $453,000,000 in cash for the purpose of funding a portion of the required amount.

The New Mountain fund’s obligation to provide the equity financing is subject to certain conditions, including:

The New Mountain fund has provided Aegion with a limited guarantee (which refer to as the “limited guarantee”) in favor of Aegion. Pursuant to the limited guarantee, the New Mountain fund guarantees Parent’s obligation for the payment of the parent termination fee (as further described in the section entitled “The Merger Agreement—Company Termination Fee; Parent Termination Fee” beginning on page 92 of this proxy statement) and certain other reimbursement and indemnification obligations of Parent, in each case, if and when required to be paid by Parent under the terms of the merger agreement and on the terms of and subject to the conditions set forth in the limited guarantee. The amount guaranteed by New Mountain Partners VI, L.P. under the limited guarantee is subject to an aggregate cap of $74,000,000 and the limited guarantee may not be enforced without giving effect to such cap.

The New Mountain fund’s obligation under the limited guarantee will automatically terminate upon the earliest to occur of (i) the consummation of the merger in accordance with the terms of the merger agreement, (ii) the valid termination of the merger agreement in any circumstance other than pursuant to which Parent would be obligated to pay the parent termination fee or the other reimbursement and indemnification obligations of Parent guarantee by the New Mountain fund pursuant to the limited guarantee, and (iii) the date on which all obligations of the New Mountain fund under the limited guarantee have been paid in full.

The following summary discusses the material U.S. federal income tax consequences of the merger to holders of shares of Aegion common stock. This discussion is based on the Internal Revenue Code of 1986, as amended (the “Code”), applicable Treasury regulations promulgated under the Code, administrative interpretations, and judicial decisions as in effect as of the date of this proxy statement, all of which may change, possibly with retroactive effect.

This discussion addresses only the consequences of the exchange of shares of Aegion common stock held as capital assets within the meaning of Section 1221 of the Code (generally, property held for investment). It does not address all aspects of U.S. federal income taxation that may be important to an Aegion stockholder in light of the Aegion stockholder’s particular circumstances, or to an Aegion stockholder that is subject to special rules, such as:

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

A “non-U.S. holder” is a beneficial owner of shares of Aegion common stock that is neither a U.S. holder nor a partnership for U.S. federal income tax purposes.

If a partnership (including any entity or arrangement treated as a partnership for U.S. federal income tax purposes) holds shares of Aegion common stock, the U.S. federal income tax treatment of a partner in the partnership will generally depend upon the status of the partner and the activities of the partnership. A partner of a partnership holding shares of Aegion common stock should consult its tax advisors.

This discussion of material U.S. federal income tax consequences is not a complete description of all potential U.S. federal income tax consequences of the merger. This discussion does not address tax consequences that may vary with, or are contingent on, individual circumstances. In addition, it does not address any alternative minimum tax, any U.S. state or local or any non-U.S. tax consequences of the merger or the potential application of the Medicare contribution tax on net investment income. Accordingly, each Aegion stockholder should consult its tax advisor to determine the particular U.S. federal, state or local or non-U.S. income or other tax consequences to it of the merger.

The receipt of the merger consideration by U.S. holders pursuant to the merger will be a taxable transaction for U.S. federal income tax purposes. In general, for U.S. federal income tax purposes, a U.S. holder will recognize taxable capital gain or loss in an amount equal to the difference, if any, between (i) the amount of cash received in the merger plus the amount used to satisfy any applicable withholding taxes and (ii) such U.S. holder’s adjusted tax basis in its shares of Aegion common stock exchanged therefor.

If a U.S. holder’s holding period in the shares of Aegion common stock surrendered in the merger is greater than one year as of the date of the merger, the capital gain or loss will be long-term capital gain or loss. Long-term capital gains of certain non-corporate holders, including individuals, are generally subject to U.S. federal income

tax at preferential rates. The deductibility of a capital loss recognized in connection with the merger is subject to limitations under the Code. If a U.S. holder acquired different blocks of shares of Aegion common stock at different times or different prices, such U.S. holder must determine its adjusted tax basis and holding period separately with respect to each block of shares of Aegion common stock that it holds.

The receipt of the merger consideration by a non-U.S. holder pursuant to the merger will not be subject to U.S. federal income tax unless:

Gain described in the first bullet point above will be subject to tax on a net income basis in the same manner as if the non-U.S. holder were a U.S. holder (unless an applicable income tax treaty provides otherwise). Additionally, any gain described in the first bullet point above of a non-U.S. holder that is a corporation also may be subject to an additional “branch profits tax” at a 30% rate (or lower rate provided by an applicable income tax treaty). A non-U.S. holder described in the second bullet point above will be subject to tax at a rate of 30% (or a lower rate provided by an applicable income tax treaty) on any capital gain realized, which may be offset by U.S.-source capital losses recognized in the same taxable year. If the third bullet point above applies to a non-U.S. holder, capital gain recognized by such holder will be subject to tax at generally applicable U.S. federal income tax rates. We believe that we are not currently, and we do not anticipate becoming, a “United States real property holding corporation.” However, because the determination of whether we are a “United States real property holding corporation” depends on the fair market value of our United States real property interests, there can be no assurance that we do not currently constitute or will not become a “United States real property holding corporation.” Non-U.S. holders owning (actually or constructively) more than 5% of Aegion common stock should consult their own tax advisors regarding the U.S. federal income tax consequences of the merger.

Payments made in exchange for shares of Aegion common stock pursuant to the merger may be subject, under certain circumstances, to information reporting and backup withholding (currently at a rate of 24%). To avoid backup withholding, a U.S. holder that does not otherwise establish an exemption should complete and return an IRS Form W-9, certifying under penalties of perjury that such U.S. holder is a “United States person” (within the meaning of the Code), that the taxpayer identification number provided is correct and that such U.S. holder is not subject to backup withholding.

A non-U.S. holder may be subject to information reporting and backup withholding (currently at a rate of 24%) on the merger consideration received in exchange for shares of Aegion common stock unless the non-U.S. holder establishes an exemption, for example, by completing the appropriate IRS Form W-8 for the non-U.S. holder, in accordance with the instructions thereto.

Any amount withheld under the backup withholding rules will be allowed as a refund or credit against the U.S. federal income tax liability of an Aegion stockholder, provided the required information is timely furnished to the IRS. The IRS may impose a penalty upon an Aegion stockholder that fails to provide the correct taxpayer identification number.

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

Aegion and Parent filed their respective HSR Act notifications on March 1, 2021. The initial 30-day waiting period expired at 11:59 p.m., Eastern Time, on March 31, 2021.

Even after the applicable waiting period under the HSR Act expires or is terminated, the FTC and the DOJ retain the authority to challenge the merger on antitrust grounds before or after the merger is completed. Likewise, at any time before or after the consummation of the merger, a U.S. state or a foreign governmental authority with jurisdiction over the parties could take such action under antitrust laws as it deems necessary or desirable in the public interest, including seeking to enjoin the consummation of the merger, to rescind the merger or to seek divestiture of particular assets. Private parties also may seek to take legal action under the antitrust laws under certain circumstances. Although there is no assurance that they will not do so, we do not expect any regulatory authority, state or private party to take legal action under the antitrust laws.

Aegion, Parent and Merger Sub have agreed to use reasonable best efforts to take, or cause to be taken, all actions and to do, or cause to be done, all actions necessary, proper or advisable to consummate, as promptly as reasonably practicable, the transactions contemplated by the merger agreement, including using reasonable best efforts to (i) obtain all authorizations, consents, orders, approvals, licenses, permits and waivers of all governmental authorities that may be or become necessary for its execution and delivery of, and the performance of its obligations pursuant to, the merger agreement and the consummation of the transactions contemplated thereby and (ii) provide such other information to any governmental authority as such governmental authority may lawfully request.

Parent and Merger Sub are required to, and to cause each of their respective affiliates to, take any and all steps necessary to avoid or eliminate each and every impediment under any antitrust law that may be asserted by any governmental authority or any other party so as to enable the parties to consummate the transactions as promptly as practicable.

If the merger is completed, Aegion common stock will be de-listed from the Nasdaq and de-registered under the Exchange Act.

On March 15, 2021, a shareholder complaint relating to the merger was filed in the United States District Court for the Southern District of New York, captioned Stein v. Aegion Corp. et al., Case No. 1:21-cv-2247. On March 19, 2021, a shareholder complaint relating to the merger was filed in the United States District Court for the Eastern District of New York, captioned Pallmer v. Aegion Corp. et al., Case No: 1:21-cv-01448. On May 29, 2021, a shareholder complaint relating to the merger was filed in the United States District Court for the Southern District of New York, captioned Griffin v. Aegion Corp. et al., Case No. 1:21-cv-02686. Each complaint alleges that the preliminary proxy statement filed by Aegion with the SEC on March 15, 2021 is false and/or misleading and asserts claims for violations of Section 14(a) and 20(a) of the Exchange Act and SEC Rule 14a-9 against Aegion and its directors. Each complaint seeks, among other things, injunctive relief preventing the merger, damages and an award of plaintiffs’ costs and disbursements, including reasonable attorneys’ and expert fees and expenses. Aegion believes that these lawsuits are without merit.

Below is a summary of the material provisions of the original merger agreement as amended by the amendment to the merger agreement, copies of which are attached to this proxy statement as Annex A and Annex B, respectively, and which are incorporated by reference into this proxy statement. This summary does not purport to be complete and may not contain all of the information about the merger agreement that is important to you. We encourage you to read carefully the original merger agreement and the amendment to the merger agreement in their entirety, as the rights and obligations of the parties thereto are governed by the express terms of the merger agreement and not by this summary or any other information contained in this proxy statement.

The following summary of the Agreement and Plan of Merger, dated as of February 16, 2021 and as amended March 13, 2021, among Parent, Merger Sub and Aegion, which we refer to as the “merger agreement,” and the copy of the original merger agreement and the amendment to the merger agreement attached as Annex A and Annex B, respectively, to this proxy statement, are intended only to provide information regarding the terms of the merger agreement. They are not intended to provide any factual information about Parent, Merger Sub or Aegion or to modify or supplement any factual disclosures about Aegion in its public reports filed with the SEC. Any material facts in Aegion’s public reports previously filed with the SEC that are incorporated by reference into this proxy statement that contradict the factual statements about Aegion contained in the merger agreement will modify such factual statements. In particular, the merger agreement and the related summary are not intended to be disclosures regarding any facts and circumstances relating to Aegion. The merger agreement contains representations and warranties by, and covenants of, Parent, Merger Sub and Aegion that were made only for purposes of the merger agreement and as of specified dates. The representations, warranties and covenants in the merger agreement were made solely for the benefit of the parties to the merger agreement, may be subject to limitations agreed upon by the contracting parties, including being qualified by confidential disclosures made for the purposes of allocating contractual risk between the parties to the merger agreement instead of establishing these matters as facts, and may be subject to contractual standards of materiality or material adverse effect applicable to the contracting parties that generally differ from those applicable to investors. In addition, information concerning the subject matter of the representations, warranties and covenants may change after the date of the merger agreement, which subsequent information may or may not be fully reflected in Aegion’s public disclosures. Until the effective time, stockholders are not third-party beneficiaries under the merger agreement.

Additional information about Aegion may be found elsewhere in this proxy statement and in Aegion’s other public filings. See the section entitled “Where You Can Find Additional Information” beginning on page 109 of this proxy statement.

The merger agreement provides that at the effective time Merger Sub will merge with and into Aegion, with Aegion continuing as the surviving corporation and as a wholly-owned subsidiary of Parent. At the effective time, all of the property, rights, privileges, immunities, powers and franchises of Aegion and Merger Sub will vest in the surviving corporation, and all debts, liabilities, obligations, restrictions and duties of Aegion and Merger Sub will become the debts, liabilities, obligations, restrictions and duties of the surviving corporation, all as provided under the Delaware General Corporation Law, which we refer to as the “DGCL.” As of the effective time, and as a result of the merger, the certificate of incorporation of the surviving corporation will be as set forth in the applicable exhibit to the merger agreement and the bylaws of the surviving corporation will be the same as the bylaws of Merger Sub in effect immediately before the effective time of the merger, and the exculpation and indemnification provisions contained in such certificate of incorporation and bylaws will not be amended, repealed or otherwise modified in any manner that would affect adversely the rights of individuals who were directors, officers, employees, fiduciaries or agents of Aegion or any subsidiary of Aegion at or prior to the effective time for at least six (6) years following the effective time.

The directors of Merger Sub immediately prior to the effective time will be the initial directors of the surviving corporation and the officers of Aegion immediately prior to the effective time will be the initial officers of the surviving corporation. The initial directors and officers will hold office until their respective successors are duly elected or appointed and qualified or until the earlier of their death, resignation or removal in accordance with the certificate of incorporation and bylaws of the surviving corporation.

The closing of the merger will take place on the date that is the later of (i) the second (2) business day after the satisfaction or waiver of the conditions to the closing set forth in the merger agreement (other than those conditions that by their terms or nature are to be satisfied at the closing, but subject to the satisfaction or, to the extent permitted by law, waiver by the party benefitting from such conditions at the closing) and (ii) April 16, 2021, or at another time or date that is mutually agreed to in writing by Aegion and Parent.

On the closing date or on another date that Aegion and Parent may agree to in writing, Aegion will file a certificate of merger with the Secretary of State of the State of Delaware as provided under the DGCL. The merger will become effective at the time the certificate of merger is duly filed with the Secretary of State of the State of Delaware or on such other date and time as may be agreed to by Aegion and Parent and specified in the certificate of merger.

At the effective time, each share of Aegion common stock issued and outstanding immediately prior to the effective time of the merger (other than shares of Aegion common stock (i) held in treasury by Aegion or owned by any direct or indirect wholly-owned subsidiary of Aegion, (ii) owned by Parent, Merger Sub or any direct or indirect wholly-owned subsidiary of Parent or (iii) for which appraisal rights have been properly demanded in writing in accordance with the DGCL) will be cancelled and automatically converted solely into the right to receive $27.00 in cash, without interest and subject to applicable tax withholding, which we refer to as the “merger consideration.” Shares of Aegion common stock described in clauses (i) and (ii) above will be cancelled at the effective time and will not be exchangeable for the merger consideration. Shares of Aegion common stock described in clause (iii) will also be cancelled at the effective time, and the holders of such shares will be entitled to the rights granted to them under Section 262 of the DGCL (as further described in the section entitled “Appraisal Rights” on page 103).

At the effective time, each share of Merger Sub common stock issued and outstanding immediately prior to the effective time of the merger will be converted into and become one validly issued, fully paid and nonassessable share of common stock, par value $0.01 per share, of the surviving corporation.

Prior to the effective time, Parent will (i) appoint a bank or trust company approved (such approval not to be unreasonably withheld, conditioned or delayed) in advance by Aegion to act as the paying agent for the purpose of effecting payments to the holders of shares of Aegion common stock entitled to receive the merger consideration, and (ii) enter into a paying agent agreement, in form and substance reasonably acceptable to Aegion, with such paying agent for the payment of the merger consideration in accordance with the merger agreement. Prior to, or substantially concurrent with, the effective time on the closing date, Parent will deposit, or will cause to be deposited, with the paying agent, for the benefit of the holders of shares of Aegion common stock issued and outstanding immediately prior to the effective time, cash in an amount sufficient to pay the aggregate merger consideration required to be paid pursuant to the merger agreement.

Promptly after the effective time (and in no event later than two (2) business days thereafter), Parent will direct the paying agent to mail to each person who was, at the effective time, a holder of record of shares of Aegion common stock entitled to receive the merger consideration: (i) a letter of transmittal and (ii) instructions for use in effecting the surrender of the stock certificates or the non-certificated shares of Aegion common stock represented by book-entry (which we refer to as “book-entry shares”) in exchange for the merger consideration. Upon proper surrender of such certificates (or effective affidavits of loss and delivery of an indemnity bond reasonable in amount, if reasonably requested by Parent, in lieu thereof, in each case in accordance with the merger agreement) to the paying agent for cancellation, together with such letter of transmittal, duly completed and validly executed in accordance with the related instructions (and such other documents as may customarily be required by the paying agent), the former holder of such shares will be entitled to receive in exchange for such shares the merger consideration which such holder has the right to receive pursuant to the merger agreement.

Any holder of book-entry shares will not be required to deliver a certificate or an executed letter of transmittal to the paying agent to receive the merger consideration that such holder is entitled to receive in accordance with the

merger agreement. Each registered holder of one or more book-entry shares will, upon receipt by the paying agent of an “agent’s” message in customary form (or such other evidence, if any, as the paying agent or Parent may reasonably require) be entitled to receive, and the surviving corporation is required to cause the paying agent to pay and deliver as soon as reasonably practicable after receipt of such agent’s message (or such other evidence, if any, as the paying agent or Parent may reasonably require), the merger consideration for each book-entry share.

Until properly surrendered as contemplated by the merger agreement, each stock certificate or book-entry share will be deemed at all times after the effective time to represent only the right to receive upon such surrender the merger consideration to which the holder of such stock certificate or book-entry share is entitled in accordance with the merger agreement. No interest will be paid or will accrue on any cash payable to holders of stock certificates or book-entry shares under the merger agreement.

From and after the effective time, holders of shares of Aegion common stock will cease to have any rights as stockholders of Aegion, except as provided in the merger agreement or by law.

Any cash deposited with the paying agent that remains undistributed to the former holders of shares of Aegion common stock twelve (12) months after the effective time will be delivered to the surviving corporation, upon demand, and any holders of shares of Aegion common stock who have not previously complied with the exchange procedures in the merger agreement may thereafter look only to the surviving corporation for, and the surviving corporation will remain liable for, payment of their claim for the merger consideration. Any amounts remaining unclaimed by holders of shares of Aegion common stock as of the earlier of (i) the fifth (5^th) anniversary of the closing date and (ii) a date which is immediately prior to such time as such amounts would otherwise escheat to or become property of any governmental authority will, to the extent permitted by applicable law, become the property of the surviving corporation free and clear of any claims or interest of any person previously entitled thereto. Neither Parent nor the surviving corporation will be liable to any person in respect of any merger consideration delivered to a public official pursuant to any applicable abandoned property, escheat or similar law.

If any stock certificate has been lost, stolen or destroyed, then upon (i) the making of an affidavit of that fact by the person claiming such stock certificate to be lost, stolen or destroyed, and (ii) if reasonably required by the surviving corporation, an indemnity bond reasonable in amount, the paying agent will pay in respect of such lost, stolen or destroyed stock certificate the merger consideration to which the holder of such stock certificate is entitled under the merger agreement. In the event of a transfer of ownership of shares of Aegion common stock that is not registered in the transfer records of Aegion, payment of the merger consideration may be made to a person other than the person in whose name the stock certificate or book-entry share so surrendered is registered if such stock certificate or book-entry share representing such shares will be presented to the paying agent, accompanied by all documents required to evidence and effect such transfer or otherwise be in proper form for transfer, and the person requesting such payment pays any transfer or other taxes required solely by reason of the payment of the merger consideration to a person other than the registered holder of such stock certificate or book-entry share or establish to the reasonable satisfaction of Parent that such tax has been paid or is not applicable.

At the effective time, (i) each Aegion restricted stock unit subject only to service-based vesting restrictions (each a “restricted stock unit”) that is outstanding as of immediately prior to the effective time will become fully vested (to the extent unvested), (ii) each Aegion restricted stock unit subject, in whole or in part, to performance-based vesting restrictions (each a “performance stock unit”) will become fully vested (to the extent unvested) as to the greater of the number of performance stock units that would vest based on target or actual performance, in each case as of immediately prior to the effective time, and (iii) each deferred stock unit outstanding as of immediately prior to the effective time will become fully vested (to the extent unvested) as of immediately prior to the effective time. Each restricted stock unit, performance stock unit, and deferred stock unit (collectively referred to as “Aegion stock units”) will be cancelled and each holder thereof will receive from the surviving corporation an amount in cash, without interest, equal to the product of the number of shares of Aegion common stock underlying each Aegion stock unit multiplied by $27.00, without interest and subject to withholding.

Pursuant to the merger agreement, the Board (or, if applicable, a committee thereof) adopted resolutions providing that (i) with respect to any “offering period(s)” (as defined in the Aegion ESPP) in progress as of February 16, 2021 under the Aegion ESPP, such offering period(s) will terminate and any option to purchase shares under the Aegion ESPP will be deemed to have been exercised upon the earlier to occur of (a) the day that is no later than two (2) business days prior to the effective time or (b) the date on which such offering period(s) would otherwise end, and no additional offering period(s) will commence under the Aegion ESPP after February 16, 2021; (ii) no individual participating in the Aegion ESPP will be permitted to (a) increase the amount of his, her or its rate of payroll contributions thereunder from the rate in effect as of February 16, 2021, or (b) except to the extent required by applicable law, make separate non-payroll contributions to the Aegion ESPP on or following February 16, 2021; (iii) no individual who is not participating in the Aegion ESPP as of February 16, 2021 may commence participation in the Aegion ESPP following February 16, 2021; (iv) the amount of the accumulated contributions of each participant under the Aegion ESPP as of immediately prior to the effective time will, to the extent not used to purchase shares in accordance with the terms and conditions of the Aegion ESPP, be refunded to such participant as of the effective time; and (v) upon consummation of the merger, the Aegion ESPP will terminate, effective immediately prior to the effective time.

Notwithstanding anything to the contrary in the merger agreement, shares of Aegion common stock that are outstanding immediately prior to the effective time and that are held by Aegion stockholders who have neither voted in favor of the merger nor consented to the merger in writing and who have demanded properly in writing appraisal for such shares in accordance with Section 262 (collectively, we refer to such shares as the “dissenting shares”) will not be converted into, or represent the right to receive, the merger consideration, unless such holder fails to perfect, withdraws or otherwise loses the right to appraisal. At the effective time, all dissenting shares will no longer be outstanding and will automatically be cancelled and will cease to exist, and, except as otherwise provided by applicable laws, each holder of dissenting shares will cease to have any rights with respect to the dissenting shares, other than such rights as are granted under Section 262. Such stockholders will be entitled to receive payment of the appraised value of such shares held by them in accordance with the provisions of Section 262, except that all dissenting shares held by stockholders who have failed to perfect or who effectively have withdrawn or lost their rights to appraisal of such shares under such Section 262 will thereupon be deemed to have been converted into, and to have become exchangeable for, as of the effective time, the right to receive the merger consideration, without any interest thereon and subject to applicable tax withholding , upon surrender, in the manner provided in the merger agreement, of the certificate or certificates that formerly evidenced such shares.

Aegion is required to give Parent (i) prompt (and in any event, within one (1) business day of receipt by Aegion) notice and copies of any demands for appraisal received by Aegion, withdrawals of such demands and any other instruments served pursuant to the DGCL and received by Aegion and (ii) the opportunity to direct and control (or, if Parent elects not to so direct and control, the right to participate (but not appear on the record) in, and be kept reasonably apprised by Aegion of all material developments with respect to) all negotiations and proceedings with respect to demands for appraisal under the DGCL. Aegion may not, except with the prior written consent of Parent, make any payment, or offer or agree to make any payment, with respect to any demands for appraisal or offer to settle or settle any such demands.

The merger agreement contains representations and warranties of Aegion and of Parent and Merger Sub.

Subject to certain exceptions in the merger agreement, in the disclosure schedule delivered by Aegion to Parent in connection with the merger agreement (which we refer to as the “disclosure schedule”) and as disclosed in Aegion’s public filings with the SEC on or after December 31, 2018, the merger agreement contains representations and warranties of Aegion as to, among other things:

Subject to certain exceptions in the merger agreement, the merger agreement also contains representations and warranties of Parent and Merger Sub as to, among other things:

Some of the representations and warranties in the merger agreement are qualified by materiality qualifications or a “material adverse effect” qualification with respect to Aegion or a “parent material adverse effect” with respect to Parent.

For purposes of the merger agreement, a “material adverse effect” with respect to Aegion means any change, effect, event, occurrence, development, condition or fact that, individually or in the aggregate, either (1) has had or would reasonably be expected to have a material adverse effect on the business, condition (financial or otherwise), assets, liabilities or results of operations of Aegion and its subsidiaries, taken as a whole or (2) the ability of Aegion to consummate the transactions contemplated by the merger agreement or to perform its obligations under the merger agreement.

However, with respect to the clause (1) described above, no change, effect, event, occurrence, development, condition or fact resulting from or relating to any of the following, alone or in combination, will be deemed to constitute, or be taken into account in determining whether there has been, or there is reasonably expected to be, a material adverse effect:

However, with respect to the exceptions described in the first, second, third, fourth, fifth and seventh bullet points above, such exceptions will only apply to the extent that such change, effect, event, occurrence, development, condition or fact does not have a materially disproportionate impact on Aegion and its subsidiaries, taken as a whole, as compared to other companies in the industries in which Aegion and its subsidiaries operate.

For the purpose of the merger agreement, a “parent material adverse effect” with respect to Parent means any change, effect, event, occurrence, development, condition or fact that, individually or in the aggregate, (i) prevents materially delays or impedes the consummation of the transactions contemplated by the merger agreement by Parent or Merger Sub or otherwise prevents, materially delays or impedes Parent or Merger Sub from performing their obligations under the merger agreement or (ii) would reasonably be expected to prevent, materially and adversely delay or impede the consummation of the transactions contemplated by the merger agreement by Parent or Merger Sub or otherwise prevent, materially and adversely delay or impede Parent or Merger Sub from performing its obligations under the merger agreement.

The merger agreement provides that, during the period commencing on February 16, 2021, and ending at the effective time of the merger, except (i) as set forth in the disclosure schedule or as otherwise expressly provided by the merger agreement or for matters required by law, or (ii) as consented to in writing by Parent, which consent is not permitted under the merger agreement to be unreasonably withheld, conditioned or delayed, Aegion must, and must cause each of its subsidiaries to, conduct its business in the ordinary course in all material respects, and use commercially reasonable efforts to preserve materially intact its and its subsidiaries’ business organization, preserve in all material respects Aegion’s and its subsidiaries’ relationships with key employees and others having significant business dealings with Aegion or any of its subsidiaries and comply in all material respects with applicable law. Further, the merger agreement also provides that, from February 16, 2021, through the effective time of the merger, except (i) as set forth in the disclosure schedule to the merger agreement or as otherwise expressly required by the merger agreement or for matters required by law, (ii) with the prior written consent of Parent, which consent is not permitted under the merger agreement to be unreasonably withheld, conditioned or delayed or (iii) for actions taken reasonably and in good faith in response to an imminent threat to human health or safety arising from COVID-19 (provided that prior to taking any such actions that Aegion intends to take in reliance on the foregoing COVID-19 related exception, Aegion is required to use commercially reasonable efforts to provide advance notice to and consult with Parent (if reasonably practicable) prior to taking such actions), Aegion must not, and must not permit any of its subsidiaries, to do any of the following (among other prohibitions):