TLP Transmontaigne Partners L.P. Transmontaigne Partners L.P. Common Units Representing Limited Partner Interests

NOTICE OF SPECIAL MEETING OF UNITHOLDERS
TO BE HELD ON                        , 2019

        Notice is hereby given that TransMontaigne Partners L.P. will hold a special meeting of its unitholders at                        , on                        , 2019, beginning at             a.m. (local time) (the "Special Meeting"), for the purpose of considering and voting on the following matters:

•

Merger Proposal:   To consider and vote on a proposal to approve the Agreement and Plan of Merger, dated as of November 25, 2018 (the "Merger Agreement"), by and among TransMontaigne Partners L.P. (the "Partnership"), TransMontaigne GP L.L.C., the general partner of the Partnership (the "General Partner"), TLP Finance Holdings, LLC ("Parent"), TLP Merger Sub, LLC ("Merger Sub"), TLP Acquisition Holdings, LLC ("TLP Holdings") and, solely for the purposes of Section 6.19 thereof, TLP Equity Holdings, LLC ("Equity Holdings"), a copy of which is attached as Annex A to the proxy statement accompanying this notice, as such agreement may be amended from time to time, and the merger of Merger Sub with and into the Partnership, with the Partnership surviving as a wholly owned subsidiary of Parent and the General Partner (the "Merger"), each of whom are indirect controlled subsidiaries of ArcLight Energy Partners Fund VI, L.P. ("ArcLight"); and



•

Adjournment Proposal:   To consider and vote on a proposal to approve the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting.

        These items of business are more fully described in the accompanying proxy statement.

        The conflicts committee of the board of directors of the General Partner (the "GP Board" and such conflicts committee, the "Conflicts Committee"), consisting of three independent directors, has unanimously (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and holders of common units representing limited partner interests in the Partnership ("Common Units") other than TLP Holdings, Parent, Merger Sub, the General Partner, Equity Holdings and their respective affiliates (the "Unaffiliated Unitholders"), (ii) approved the Merger Agreement and the transactions contemplated thereby, including the Merger, and (iii) recommended that the GP Board and the holders of Common Units approve the Merger Agreement and the Merger, such recommendation and approval constituting "Special Approval" as such term is defined in the First Amended and Restated Agreement of Limited Partnership of the Partnership (as amended, the "Partnership Agreement"). In determining to make its recommendation, the Conflicts Committee considered, among other things, the opinion of Evercore Group L.L.C. ("Evercore"), the financial advisor to the Conflicts Committee, to the effect that, as of the date of its opinion, and based upon the assumptions made, matters considered, procedures followed, and qualifications and limitations of the review undertaken in rendering its opinion as set forth therein, the Merger Consideration was fair, from a financial point of view, to the Unaffiliated Unitholders. The full text of the written opinion of Evercore is attached to this proxy statement as Annex B.

         The GP Board, after considering various factors, including the unanimous determination and recommendation of the Conflicts Committee, has determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders and has approved the Merger Agreement and the transactions contemplated thereby, including the Merger. Accordingly, the GP Board recommends that the holders of all Common Units (the "Unitholders") vote "FOR" the Merger Proposal and vote "FOR" the Adjournment Proposal.

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        Only Unitholders of record as of the close of business on                        , 2019 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 Unitholders entitled to vote at the Special Meeting will be available in the Partnership's offices located at 1670 Broadway, Suite 3100, Denver, Colorado 80202, during regular business hours for a period of 10 days before the Special Meeting, and at the place of the Special Meeting during the meeting.

        Approval of the Merger Agreement and the Merger is a condition to the consummation of the Merger and requires the affirmative vote of holders of at least a majority of the issued and outstanding Common Units. Concurrently with the execution of the Merger Agreement, the Partnership, TLP Holdings and Equity Holdings entered into a support agreement included as Annex C in the attached proxy statement (the "Support Agreement") pursuant to which TLP Holdings agreed to vote or cause the 800,000 Common Units it owns to be voted and Equity Holdings agreed to vote or cause the 2,366,704 Common Units it owns to be voted in favor of the Merger, the adoption of the Merger Agreement and any other matter necessary or desirable for the consummation of the transactions contemplated by the Merger Agreement, including the Merger. Unitholders will also vote on a proposal to adjourn the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting. Therefore, your vote is very important. Your failure to vote your Common Units will have the same effect as a vote "AGAINST" the approval of the Merger Agreement and the Merger.

        You can cause your Common Units to be voted by completing a proxy card, a form of which is included as Annex D in the attached proxy statement, and returning it in the prepaid envelope provided. Most Unitholders can also submit their proxies over the Internet or by telephone. If Internet and telephone submission are available to you, you can find instructions in the materials accompanying the proxy statement. You can revoke a proxy at any time prior to its exercise at the Special Meeting by following the instructions in the enclosed proxy statement.

        The accompanying proxy statement is dated                        , 2019 and is first being mailed to Unitholders on or about                        , 2019.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved the Merger, passed upon the merits of fairness of the merger or passed upon the adequacy or accuracy of the disclosure in this proxy statement. Any representation to the contrary is a criminal offense.

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YOUR VOTE IS IMPORTANT!

         WHETHER OR NOT YOU EXPECT TO ATTEND THE SPECIAL MEETING IN PERSON, WE URGE YOU TO SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE (i) BY TELEPHONE, (ii) VIA THE INTERNET OR (iii) BY MARKING, SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE PREPAID ENVELOPE PROVIDED. You may revoke your proxy or change your voting instructions at any time before the Special Meeting. If your common units representing limited partner interests in the Partnership ("Common Units") are held in the name of a bank, broker or other fiduciary, please follow the instructions on the voting instruction card furnished to you by such record holder.

        We urge you to read the accompanying proxy statement, including all documents incorporated by reference into the accompanying proxy statement, and its annexes carefully and in their entirety. If you have any questions concerning the Merger Proposal, the Adjournment Proposal, the Special Meeting or the accompanying proxy statement or would like additional copies of the accompanying proxy statement or need help voting your Common Units, please contact the Partnership's proxy solicitor:

Georgeson LLC
1290 Avenue of the Americas, 9 ^th  Floor
New York, NY 10104
(888) 642-8066 (Toll Free)

REFERENCES TO ADDITIONAL INFORMATION

         This proxy statement incorporates by reference important business and financial information about the Partnership from other documents that are not included in or delivered with the proxy statement. For a more detailed discussion of the information about the Partnership incorporated by reference into the proxy statement, see " Where You Can Find More Information ," beginning on page 102. This information is available to you without charge upon your request. You can obtain the documents incorporated by reference into this proxy statement by requesting them in writing or by telephone from the appropriate party at the following addresses and telephone number:

TransMontaigne Partners L.P.
1670 Broadway, Suite 3100
Denver, Colorado 80202
Phone: (303) 626-8200

        To obtain timely delivery of these documents, you must request them no later than five business days before the date of the Special Meeting. This means that Unitholders requesting documents must do so by                        , 2019 in order to receive them before the Special Meeting.

ABOUT THIS DOCUMENT

        This document constitutes a notice of meeting and a proxy statement with respect to the Special Meeting of Unitholders, during which Unitholders will be asked to consider and vote on, among other matters, a proposal to approve the Merger Agreement and the Merger.

        You should rely only on the information contained in or incorporated by reference into this proxy statement. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this proxy statement. This proxy statement is dated                        , 2019. The information contained in this proxy statement is accurate only as of that date or, in the case of information in a document incorporated by reference, as of the date of such document, unless the information specifically indicates that another date applies. Neither the mailing of this proxy statement to the Unitholders nor the payment of the merger consideration pursuant to the Merger Agreement will create any implication to the contrary.

        This proxy statement does not constitute the solicitation of a proxy in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

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SUMMARY TERM SHEET

         The following summary highlights selected information in this proxy statement and may not contain all of the information that may be important to you. Accordingly, the Partnership encourages you to read carefully this entire proxy statement, its annexes and the documents referred to in and incorporated by reference into this proxy statement. You may obtain the information incorporated by reference into this proxy statement without charge by following the instructions in the section entitled "Where You Can Find More Information" beginning on page 102 of this proxy statement.

Parties to the Merger (see page 22) :

TRANSMONTAIGNE PARTNERS L.P.
1670 Broadway, Suite 3100
Denver, Colorado 80202
Phone: (303) 626-8200

        TransMontaigne Partners L.P., a Delaware limited partnership (the "Partnership"), is a terminaling and transportation company with assets and operations in the United States along the Gulf Coast, in the Midwest, in Houston and Brownsville, Texas, along the Mississippi and Ohio Rivers, in the Southeast and on the West Coast. The Partnership provides integrated terminaling, storage, transportation and related services for customers engaged in the distribution and marketing of light refined petroleum products, heavy refined petroleum products, crude oil, chemicals, fertilizers and other liquid products. The Partnership's Common Units are listed on the New York Stock Exchange (the "NYSE") under the ticker symbol "TLP."

TRANSMONTAIGNE GP L.L.C.
1670 Broadway, Suite 3100
Denver, Colorado 80202
Phone: (303) 626-8200

        TransMontaigne GP L.L.C., a Delaware limited liability company (the "General Partner"), is the general partner of the Partnership. Its board of directors (the "GP Board") and executive officers manage the Partnership. The General Partner is a direct wholly owned subsidiary of TLP Holdings.

TLP FINANCE HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        TLP Finance Holdings, LLC, a Delaware limited liability company ("Parent"), is a direct wholly owned subsidiary of TLP Holdings. Parent has not carried on any activities or operations to date, except for those activities incidental to its formation on October 16, 2017 and undertaken in connection with the transactions contemplated by the Merger Agreement.

TLP MERGER SUB, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        TLP Merger Sub, LLC, a Delaware limited liability company ("Merger Sub"), is a direct wholly owned subsidiary of Parent formed solely for the purpose of facilitating the Merger. Merger Sub has not carried on any activities or operations to date, except for those activities incidental to its formation and undertaken in connection with the transactions contemplated by the Merger Agreement. By

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operation of the Merger, Merger Sub will be merged with and into the Partnership, with the Partnership surviving the Merger as a wholly owned subsidiary of Parent and the General Partner.

TLP ACQUISITION HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        TLP Acquisition Holdings, LLC, a Delaware limited liability company ("TLP Holdings"), is an indirect subsidiary of, and controlled by, ArcLight. TLP Holdings is a direct wholly owned subsidiary of PPH Management Holdings, LLC, a Delaware limited liability company, which is a direct, controlled subsidiary of Pike Petroleum Holdings, LLC, a Delaware limited liability company ("Pike Holdings"). Pike Petroleum Fund VI, LLC, a Delaware limited liability company, owns approximately 54.0% of Pike Holdings, and is a direct wholly owned subsidiary of Pike Petroleum Holdings Fund VI Holdings, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of ArcLight.

TLP EQUITY HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        TLP Equity Holdings, LLC, a Delaware limited liability company ("Equity Holdings"), is a direct wholly owned subsidiary of ArcLight.

The Merger

        Parent, an indirect controlled subsidiary of ArcLight Energy Partners Fund VI, L.P. ("ArcLight"), has agreed to acquire all of the publicly held equity (other than the Sponsor Units (as defined below)) in the Partnership under the terms of the Merger Agreement, as described in this proxy statement. Under the terms of the Merger Agreement, Merger Sub will merge with and into the Partnership, with the Partnership surviving as a wholly owned subsidiary of Parent and the General Partner, each of whom are indirect controlled subsidiaries of ArcLight. The Merger Agreement is attached as Annex A to this proxy statement. We encourage you to read the Merger Agreement because it is the legal document that governs the terms and conditions of the Merger.

Merger Consideration (see page 77)

        The Merger Agreement provides that, at the effective time of the Merger (the "Effective Time"), each Common Unit issued and outstanding or deemed issued and outstanding as of immediately prior to the Effective Time, other than Common Units held by Parent, TLP Holdings, Equity Holdings or their respective permitted transferees ("Sponsor Units"), will be converted into the right to receive $41.00 in cash, to be paid without interest and reduced by any applicable tax withholding. In addition, until the closing of the Merger, the Unitholders will continue to receive regular quarterly distributions of $0.805 per Common Unit with respect to any completed quarter prior to closing, regardless of whether the closing occurs prior to or after the applicable record date (collectively, the "Merger Consideration"). As of the Effective Time, all of the Common Units converted into the right to receive the Merger Consideration will no longer be outstanding and will automatically be cancelled and cease to exist. The Sponsor Units will not be cancelled, will not be converted into the Merger Consideration and will remain outstanding following the Effective Time. The Partnership's phantom units under the TLP Management Services LLC Savings and Retention Plan, effective February 26, 2016 (as amended from time to time and including any successor or replacement plan or plans, the "Savings and Retention Plan"), established pursuant to the TLP Management Services LLC 2016 Long-Term

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Incentive Plan, effective February 26, 2016 (as amended from time to time and including any successor or replacement plan or plans, the "LTIP," and together with the Savings and Retention Plan, the "Equity Plans"), will be converted into a right to receive a cash payment in an amount equal to the Merger Consideration with respect to each such phantom unit, which amount (i) will be treated as "Covered Compensation" under the Savings and Retention Plan, vest and be payable in accordance with the terms of the underlying award agreement or letter (or the Savings and Retention Plan, if there is no separate award agreement or letter), and (ii) will be adjusted from and after the Effective Time in accordance with the Savings and Retention Plan. Prior to the Effective Time, TLP Holdings, the Partnership and the General Partner will cooperate to take all actions necessary, if any, to eliminate any obligation under the Equity Plans to grant or issue any rights with respect to Common Units or other equity interests in the Partnership.

Treatment of General Partner Interest and Incentive Distribution Rights (see page 78)

        As a result of the Merger, each of the Partnership's general partner units issued and outstanding immediately prior to the Effective Time will be converted into (i) one Common Unit, which Common Unit will be unchanged and remain outstanding following the Merger, and (ii) in aggregate, a non-economic general partner interest in the surviving entity. As of the Effective Time, all of the Partnership's general partner units will no longer be outstanding and will automatically be cancelled and cease to exist, and no consideration will be delivered in respect thereof.

        The Partnership's Incentive Distribution Rights ("IDRs") issued and outstanding immediately prior to the Effective Time will be converted into 100 Common Units, which Common Units shall be unchanged and remain outstanding following the Merger. As of the Effective Time, all IDRs will no longer be outstanding and will automatically be cancelled and cease to exist, and no consideration shall be delivered in respect thereof.

Effects of the Merger (see page 28)

        If the Merger is completed, (i) the Partnership will become a wholly owned subsidiary of Parent and the General Partner, and holders of Common Units other than TLP Holdings, Parent, Merger Sub, the General Partner, Equity Holdings and their respective affiliates (the "Unaffiliated Unitholders") will no longer have an equity interest in the Partnership, (ii) the Common Units will no longer be listed on the NYSE and (iii) the registration of the Common Units with the Securities and Exchange Commission (the "SEC") under the Securities Exchange Act of 1934, as amended (the "Exchange Act") will be terminated.

The Partnership Special Meeting (see page 24)

Special Meeting

        The Special Meeting will be held at            , on            , 2019, at             a.m. (local time). At the Special Meeting, Unitholders will be asked to vote on the following proposals:

•

Merger Proposal:   To approve the Merger Agreement, a copy of which is attached as Annex A to this proxy statement, as such agreement may be amended from time to time, and the Merger (the "Merger Proposal"); and



•

Adjournment Proposal:   To approve the adjournment of the Special Meeting, if necessary or appropriate to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting (the "Adjournment Proposal," and together with the Merger Proposal, the "Proposals").

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Who Can Vote at the Special Meeting

        Only Unitholders of record at the close of business on            , 2019 (the "record date") will be entitled to receive notice of the Special Meeting and to vote on the Proposals at the Special Meeting. As of the close of business on the record date of            , 2019, there were            Common Units held by Unitholders entitled to vote on the Proposals. Each Unitholder is entitled to one vote for each Common Unit owned as of the record date.

Required Vote

        The affirmative vote of holders of at least a majority of the issued and outstanding Common Units is required to approve the Merger Agreement and the Merger (such approval, "Unitholder Approval"). As of the record date, there were            Common Units outstanding and held by Unitholders. Pursuant to the Support Agreement, TLP Holdings has agreed to vote or cause the 800,000 Common Units, representing approximately        % of the total issued and outstanding Common Units, it owns and Equity Holdings has agreed to vote or cause the 2,366,704 Common Units, representing approximately        % of the total issued and outstanding Common Units, it owns to be voted in favor of the Merger, the adoption of the Merger Agreement and any other matter necessary or desirable for the consummation of the transactions contemplated by the Merger Agreement, including the Merger.

        Accordingly, the affirmative vote of the Unaffiliated Unitholders representing approximately        % of the total issued and outstanding Common Units (in addition to the Common Units to be voted by TLP Holdings and Equity Holdings) is necessary to approve the Merger Agreement and the Merger. The affirmative vote of holders of at least a majority of the issued and outstanding Common Units is required to approve the adjournment of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting if a quorum is present at the meeting; provided that, if a quorum is not present at the meeting, the affirmative vote of holders of a majority of the issued and outstanding Common Units entitled to vote at such meeting represented either in person or by proxy is required to approve the Adjournment Proposal.

        Abstentions will have the same effect as votes "AGAINST" approval of the Merger Proposal and if you fail to cast your vote in person or by proxy or fail to give voting instructions to your broker, bank or other nominee and are otherwise represented in person or by proxy, it will have the same effect as a vote "AGAINST" the Merger Proposal.

The Conflicts Committee and GP Board Recommendations and Reasons for the Merger (see page 38)

        The conflicts committee of the GP Board (the "Conflicts Committee"), consisting of three independent directors, has unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders, approved the Merger Agreement and the Merger, and recommended that the GP Board and the Unitholders approve the Merger Agreement and approve the transactions contemplated thereby, including the Merger, such recommendation and approval constituting "Special Approval" as such term is defined in the First Amended and Restated Agreement of Limited Partnership of the Partnership (as amended, the "Partnership Agreement").

        The GP Board recommends that Unitholders vote "FOR" the approval of the Merger Agreement and "FOR" the adjournment of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger at the time of the Special Meeting.

        In the course of reaching its decision to approve the Merger Agreement and the Merger, the Conflicts Committee and the GP Board considered a number of factors in their deliberations. For a

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more complete discussion of these factors, see " Special Factors—Recommendation of the Conflicts Committee and the GP Board; Reasons for Recommending Approval of the Merger Proposal " beginning on page 38.

The Conflicts Committee and GP Board's Approval of the Merger (see page 38)

        In connection with the Merger, the GP Board delegated to the Conflicts Committee the power and authority to (i) review and evaluate the terms and conditions of, and to determine the advisability of, the Merger on behalf of the Partnership and the Unaffiliated Unitholders, (ii) negotiate, or delegate to any person or persons the ability to negotiate, with TLP Holdings and its affiliates and their representatives, or any other appropriate person, with respect to the terms and conditions of the Merger, (iii) determine whether or not to approve the Merger by "Special Approval" (pursuant to Section 7.9(a) of the Partnership Agreement), and (iv) make any recommendations to the GP Board regarding the Merger as the Conflicts Committee shall determine to be appropriate. The Conflicts Committee conducted an extensive review and evaluation of the proposed Merger. The Conflicts Committee retained Evercore L.L.C. ("Evercore") as its financial advisor and Richards, Layton & Finger, P.A. ("RLF") as its legal counsel. In the course of reaching its decision to approve the Merger Agreement and the transactions contemplated thereby, including the Merger, each of the Conflicts Committee and the GP Board considered a number of factors in their deliberations. For a more complete discussion of these items, see " Special Factors—Recommendation of the Conflicts Committee and the GP Board; Reasons for Recommending Approval of the Merger Proposal ."

Opinion of Financial Advisor to the Conflicts Committee (see page 45)

        In connection with the proposed Merger and related transactions, at the request of the Conflicts Committee, at a meeting of the Conflicts Committee held on November 25, 2018, Evercore rendered its oral opinion to the Conflicts Committee (subsequently confirmed in writing) to the effect that, as of November 25, 2018, and based upon the assumptions made, matters considered, procedures followed, and qualifications and limitations of the review undertaken in rendering its opinion as set forth therein, the Merger Consideration was fair, from a financial point of view, to the Unaffiliated Unitholders.

         The full text of Evercore's written opinion, which describes the assumptions made, matters considered, procedures followed, and qualifications and limitations of the review undertaken in rendering such opinion as set forth therein, is attached as Annex B to this proxy statement and is incorporated herein by reference. The description of Evercore's opinion set forth in this proxy statement is qualified in its entirety by reference to the full text of Evercore's opinion. Evercore's opinion was prepared at the request and for the benefit and use of the Conflicts Committee (in its capacity as such) in connection with its evaluation of the Merger and Evercore did not express any opinion on any other terms, aspects or implications of the Merger or any related transactions. Evercore expressed no opinion as to the relative merits of the Merger or any related transactions or any other transactions or business strategies discussed by the Conflicts Committee as alternatives to the Merger or any related transactions or the decision of the Conflicts Committee to proceed with the Merger or any related transactions. Evercore's opinion did not constitute and is not a recommendation to the Conflicts Committee or any other person as to any action taken on any aspect of the Merger, related transactions or any other matter. Evercore's opinion also does not constitute a recommendation to any Unitholder as to how such holder should vote or act with respect to the Merger, related transactions or any other matter .

Interests of the Directors and Executive Officers of the General Partner in the Merger (see page 63)

        Some of the directors and executive officers of the General Partner have financial interests in the Merger that may be different from, or in addition to, those of the Unitholders generally. The Conflicts Committee and the GP Board were aware of these interests and considered them, among other

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matters, in approving the Merger Agreement and making its recommendation that the Unitholders approve the Merger Agreement and the Merger. The Merger Agreement provides that each of the Partnership's phantom units under the Equity Plans will be converted into a right to receive a cash payment in an amount equal to the Merger Consideration with respect to each such phantom unit and will remain subject to the vesting schedule in the underlying award agreement or the underlying plan document, as applicable.

        The General Partner's directors and executive officers are also entitled to continued indemnification and directors' and officers' liability insurance coverage under the Merger Agreement. For a further discussion of the interests of directors and executive officers in the Merger, see " Special Factors—Interests of the Directors and Executive Officers of the General Partner in the Merger " beginning on page 63.

Position of the ArcLight Filing Parties as to the Fairness of the Merger (see page 64)

        The "Sponsor Entities" means (i) ArcLight, (ii) Parent, (iii) Merger Sub, (iv) TLP Holdings, (v) Equity Holdings, (vi) Pike Petroleum Fund VI Holdings, LLC, (vii) Pike Petroleum Holdings, LLC and (viii) PPH Management Holdings, LLC. The "ArcLight Filing Parties" means the Sponsor Entities and Daniel R. Revers (the "Controlling Affiliate"). The ArcLight Filing Parties believe that the proposed Merger is substantively and procedurally fair to the Unaffiliated Unitholders. However, none of the ArcLight Filing Parties nor any of their respective affiliates (other than the Conflicts Committee) has performed, or engaged a financial advisor to perform, any valuation or other analysis for purposes of assessing the fairness of the Merger to the Partnership and the Unaffiliated Unitholders. The belief of the ArcLight Filing Parties as to the procedural and substantive fairness of the Merger is based on the factors discussed in " Special Factor—Position of the ArcLight Filing Parties as to the Fairness of the Merger " beginning on page 64.

Conditions to the Merger (see page 73)

        Parent and the Partnership currently expect to complete the Merger in the first quarter of 2019, subject to receipt of Unitholder Approval, certain regulatory approvals and clearances, and the satisfaction or waiver of the other conditions to the transactions contemplated by the Merger Agreement described below.

        As more fully described in this proxy statement, each party's obligation to complete the transactions contemplated by the Merger Agreement depends on a number of customary closing conditions being satisfied or, where legally permissible, waived, including the following:

•

the Merger Agreement and the Merger must have been approved by the affirmative vote of the holders of at least a majority of the issued and outstanding Common Units;



•

the waiting period applicable to the consummation of the Merger under the Hart-Scott-Rodino Antitrust Improvement Act of 1976, as amended (the "HSR Act"), must have been terminated or expired and any other required regulatory approvals must have been obtained and must be in full force and effect; and



•

no law, injunction, judgment or ruling enacted, promulgated, issued, entered, amended or enforced by any governmental authority is in effect enjoining, restraining, preventing or prohibiting the consummation of the transactions contemplated by the Merger Agreement or making the consummation of such transactions illegal.

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        The obligations of Parent and Merger Sub to effect the Merger are subject to the satisfaction or waiver of the following additional conditions:

•

the representations and warranties of the Partnership and the General Partner in the Merger Agreement shall be true and correct both as of the date of the Merger Agreement and at and as of the date of the closing of the Merger (the "Closing Date") (except to the extent expressly made as of an earlier date, in which case as of such date), subject to certain standards, including materiality and material adverse effect qualifications, as described under " Proposal No. 1. The Merger Agreement—Conditions to Consummation of the Merger ;"



•

the Partnership and the General Partner shall have performed or complied with, in all material respects, all covenants and obligations required to be performed by them under the Merger Agreement at or prior to the Closing Date; and



•

Parent and Merger Sub shall have received an officer's certificate executed by an authorized executive officer of General Partner certifying that the two preceding conditions have been satisfied.

        The obligations of the Partnership to effect the Merger are subject to the satisfaction or waiver of the following additional conditions:

•

the representations and warranties of TLP Holdings, Parent and Merger Sub in the Merger Agreement shall be true and correct both as of the date of the Merger Agreement and at and as of the Closing Date (except to the extent expressly made as of an earlier date, in which case as of such date), subject to certain standards, including materiality and material adverse effect qualifications, as described under " Proposal No. 1. The Merger Agreement—Conditions to Consummation of the Merger ;"



•

TLP Holdings, Parent and Merger Sub shall have performed or complied with, in all material respects, all covenants and obligations required to be performed by them under the Merger Agreement and the Partnership shall have received a certificate signed on behalf of Parent by an executive officer of Parent to such effect at or prior to the Closing Date; and



•

the Partnership shall have received an officer's certificate executed by an authorized executive officer of TLP Holdings certifying that the two preceding conditions have been satisfied.

Regulatory Approvals Required for the Merger (see page 68)

        Consummation of the Merger is subject to the expiration or termination of a 30-day waiting period under the HSR Act. On December 7, 2018, ArcLight and the Partnership filed Notification and Report Forms with the Antitrust Division of the Department of Justice (the "Antitrust Division") and the Federal Trade Commission (the "FTC") to begin the waiting period applicable to the consummation of the Merger under the HSR Act. See " Special Factors—Regulatory Approvals and Clearances Required for the Merger ."

No Solicitation by the General Partner or the Partnership of Alternative Proposals (see page 75)

        Under the Merger Agreement, the Partnership and the General Partner have agreed that they will not, and will use reasonable best efforts to cause their and the Partnership's subsidiaries' respective directors, officers, employees, investment bankers, financial advisors, attorneys, accountants, agents and other representatives not to, directly or indirectly (i) initiate, solicit, knowingly encourage or knowingly facilitate (including by way of furnishing confidential information) or take any other action intended to lead to any inquiries or the making or submission of any proposals that constitute or could reasonably

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be expected to lead to any inquiry, proposal or offer from or by any person or entity, other than Parent, Merger Sub or their respective affiliates, relating to any:

•

direct or indirect acquisition (whether in a single transaction or a series of related transactions) of (i) more than 15% of the assets of the Partnership and its subsidiaries, taken as a whole, (ii) more than 15% of the outstanding equity securities of the Partnership or (iii) a business or businesses that constitute more than 15% of the cash flow, net revenues or net income of the Partnership and its subsidiaries, taken as a whole;



•

tender offer or exchange offer, as defined under the Exchange Act, that, if consummated, would result in any person or "group" (as defined in Section 13(d) of the Exchange Act) beneficially owning more than 15% of the outstanding equity securities of the Partnership; or



•

merger, consolidation, business combination, recapitalization, liquidation, dissolution or similar transaction involving the Partnership or any of its subsidiaries, other than the Merger, which is structured to permit a person or "group" (as defined in Section 13(d) of the Exchange Act) to acquire beneficial ownership of at least 15% of the Partnership's consolidated assets, net income, net reserves or equity securities (collectively, an "Acquisition Proposal"),

or (ii) participate in any discussions or negotiations regarding, or furnish to any person or entity any non-public information with respect to, any Acquisition Proposal or (iii) enter into any confidentiality agreement, merger agreement, letter of intent, agreement in principle, unit purchase agreement, asset purchase agreement or unit exchange agreement, option agreement or similar agreement relating to an Acquisition Proposal.

        The Merger Agreement also requires the Partnership and the General Partner to immediately cease and cause to be terminated any discussions or negotiations with any person conducted prior to the execution of the Merger Agreement with respect to an Acquisition Proposal, requires the return or destruction of all confidential information previously provided to such parties by or on behalf of the Partnership or its subsidiaries and prohibits any access by any person (other than Parent and its representatives) to any physical or electronic data room relating to a possible Acquisition Proposal.

Change in the GP Board Recommendation (see page 76)

        The Merger Agreement provides that the Partnership and the General Partner will not, and will use reasonable best efforts to cause the Partnership's subsidiaries and their respective representatives not to, directly or indirectly, withdraw, modify or qualify, or propose publicly to (i) withdraw, modify or qualify, in a manner adverse to Parent, the recommendation of the GP Board that the Unitholders approve the Merger Agreement or publicly recommend the approval or adoption of, or publicly approve or adopt, or propose to publicly recommend, approve or adopt, any Acquisition Proposal, or fail to recommend against acceptance of any tender offer or exchange offer for Common Units within 10 business days after commencement of such offer, or resolve or agree to take any of the foregoing actions or (ii) fail to include the recommendation of the GP Board that the Unitholders approve the Merger Agreement recommendation in the proxy statement.

        The Partnership or the General Partner's taking or failing to take, as applicable, any of the actions described above is referred to as a "Partnership Adverse Recommendation Change."

        Subject to the satisfaction of specified conditions in the Merger Agreement described under " Proposal No. 1. The Merger Agreement—Change in the GP Board Recommendation ," the Conflicts Committee may, at any time prior to the approval of the Merger Agreement by the Unitholders, effect a Partnership Adverse Recommendation Change if it determines in good faith (after consultation with its financial advisors and outside legal counsel) that the failure to take such action would constitute a breach of, or be otherwise inconsistent with, the Conflict Committee's duties under the Partnership Agreement or applicable law.

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Termination of the Merger Agreement (see page 79)

        Parent or the Partnership may terminate the Merger Agreement at any time prior to the Effective Time:

•

by mutual written consent, duly authorized by the consent of, in the case of the Partnership, the Conflicts Committee, and in the case of Parent, TLP Holdings, the managing member of Parent;



•

by either Parent or, following authorization by the Conflicts Committee, the Partnership:



•

if the Merger has not occurred on or before June 30, 2019 (the "Outside Date"); provided, that the right to terminate is not available to a party if the inability to satisfy such condition was due to the failure of such party (or, in the case of Partnership, the General Partner, and in the case of Parent, TLP Holdings or Merger Sub) to perform any of its obligations under the Merger Agreement or if any other party has filed and is pursuing an action seeking specific performance pursuant to the terms of the Merger Agreement;



•

if any governmental authority has enacted, promulgated, issued, entered, amended or enforced any final and nonappealable law, injunction, judgment or ruling that enjoins, restrains, prevents or prohibits the consummation of the transactions contemplated by the Merger Agreement or makes the transactions contemplated by the Merger Agreement illegal; provided, however, that the right to terminate is not available to a party if such final law, injunction, judgment or rule was due to the failure of such party (or, in the case of Partnership, the General Partner, and in the case of Parent, TLP Holdings or Merger Sub) to perform in all material respects any of its obligations under the Merger Agreement; or



•

if the Unitholder Approval is not obtained at the Special Meeting or any adjournment or postponement of such meeting is also not approved;



•

by Parent:



•

if a Partnership Adverse Recommendation Change by the GP Board has occurred; or



•

if there is a breach or failure to perform by the Partnership or the General Partner of any of its representations, warranties, covenants or agreements in the Merger Agreement such that certain closing conditions would not be satisfied, or if capable of being cured, such breach has not been cured within the earlier of the Outside Date or 30 days following delivery of written notice of such breach by Parent, subject to certain exceptions discussed in " Proposal No. 1. The Merger Agreement—Termination of the Merger Agreement ;" provided, however, that the right to terminate is not available to Parent if TLP Holdings, Parent or Merger Sub is then in material breach of any of its representations, warranties, covenants or agreements contained in the Merger Agreement; or



•

by the Partnership (following authorization by the Conflicts Committee):



•

if there is a breach or failure to perform by TLP Holdings, Parent or Merger Sub of any of their representations, warranties, covenants or agreements in the Merger Agreement such that certain closing conditions would not be satisfied, or if capable of being cured, such breach has not been cured within the earlier of the Outside Date or 30 days following delivery of written notice of such breach by the Partnership, subject to certain exceptions discussed in " Proposal No. 1. The Merger Agreement—Termination of the Merger Agreement ;" provided, however, that the right to terminate is not available to the Partnership if the Partnership or the General Partner is then in material breach of any of its representations, warranties, covenants or agreements contained in the Merger Agreement; or



•

if (i) all conditions to closing have been met or waived, (ii) the Partnership and the General Partner are ready, willing and able to close, (iii) the General Partner has delivered written

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notice to Parent of, among other things its and the Partnership's willingness and ability to close the Merger on the date of such notice and at all times during the five business days immediately after such notice as more fully described in " Proposal No. 1. The Merger Agreement—Termination of the Merger Agreement " and (iv) Parent fails to consummate the closing within those five business days.

Fees and Expenses (see page 70)

        Generally, all fees and expenses incurred in connection with the transactions contemplated by the Merger Agreement will be the obligation of the respective party incurring such fees and expenses. The filing fee under the HSR Act and any other applicable antitrust law will be paid 50% by Parent and 50% by the Partnership.

Remedies, Specific Performance (see page 81)

        The Merger Agreement provides that no termination of the Merger Agreement will relieve the Partnership from any liability for any failure to consummate the Merger and the other transactions contemplated thereby when required pursuant to the Merger Agreement, and that in the event of the Partnership's or the General Partner's intentional and material breach of the Merger Agreement or intentional fraud, then Parent shall be entitled to pursue any and all legally available remedies, including equitable relief, and to seek recovery of all losses, liabilities, damages, costs and expenses of every kind and nature (including reasonable attorneys' fees and time value of money). Notwithstanding anything to the contrary therein, the Merger Agreement also provides that the Partnership is to pay to Parent its reasonable and documented out-of-pocket expenses incurred in connection with the Merger Agreement and the transactions contemplated thereby, including the Merger Agreement, up to an amount equal to $5,000,000, in the event the Merger Agreement is terminated under certain circumstances.

        Further, notwithstanding anything to the contrary therein, the Merger Agreement also provides that Parent is to pay to the Partnership (or its designated subsidiary assignee) a termination fee of an amount equal to $27,000,000 (the "Termination Fee") in the event the Merger Agreement is terminated under certain circumstances (it being understood that in no event shall Parent be required to pay the Termination Fee on more than one occasion). The Merger Agreement also provides that the parties are entitled to obtain an injunction to prevent breaches of the Merger Agreement and to specifically enforce the Merger Agreement. The Termination Fee is (together with certain specific performance rights) the sole and exclusive remedy of the Partnership or the General Partner or any of their respective affiliates against Parent, TLP Holdings, Equity Holdings, Merger Sub or any of their respective affiliates and under no circumstances shall Parent be obligated to both specifically perform the terms of the Merger Agreement and pay the Termination Fee.

Financing of the Merger (see page 69)

        In order to provide financing for the Merger Consideration, ArcLight entered into an equity commitment letter with Parent, committing ArcLight to fund up to approximately $33.7 million in equity financing (the "Equity Commitment Letter"). In addition, concurrently with the execution of the Merger Agreement, Parent entered into a $525,000,000 senior secured credit facility providing debt financing for the Merger (together with the Equity Commitment Letter, the "Financing Documents"). The Financing Documents provide Parent with binding financial commitments that, when funded at closing (assuming the conditions to the Merger are satisfied), will provide Parent with funds sufficient to pay the Merger Consideration and pay all of the fees and expenses of Parent and Merger Sub required to be paid at closing.

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Material U.S. Federal Income Tax Consequences of the Merger (see page 95)

        The receipt of cash in exchange for Common Units pursuant to the Merger will be a taxable transaction to U.S. Unitholders (as defined in the section titled "Material U.S. Federal Income Tax Consequences") for U.S. federal income tax purposes. In general, gain or loss recognized on the receipt of cash in exchange for Common Units will be taxable as capital gain or loss. However, a portion of this gain or loss, which portion could be substantial, will be separately computed and taxed as ordinary income or loss under Section 751 of the U.S. Internal Revenue Code of 1986, as amended, and the rules and regulations promulgated thereunder (the "Code"), to the extent attributable to assets giving rise to "unrealized receivables," including depreciation recapture, or to "inventory items" owned by the Partnership and its subsidiaries. Passive losses that were not deductible by a U.S. Unitholder in prior taxable periods because they exceeded the Unitholder's share of the Partnership's income may become available to offset a portion of the gain recognized by such Unitholder. However, the precise U.S. federal income tax consequences of the Merger will depend on the Unitholder's personal tax situation. Accordingly, each Unitholder should consult its tax advisor regarding the tax consequences of the exchange of Common Units for cash pursuant to the Merger in light of its particular circumstances (including the application and effect of any state, local or foreign income and other tax laws).

No Appraisal Rights (see page 71)

        Appraisal rights are not available in connection with the Merger under the laws of the State of Delaware or under the Partnership Agreement.

Delisting and Deregistration of Common Units (see page 71)

        The Common Units are currently listed on the NYSE under the ticker symbol "TLP." If the Merger is completed, the Common Units will cease to be listed on the NYSE and will be deregistered under the Exchange Act.

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Organizational Structure Prior to the Merger

        The following represents the simplified organizational structure of the Partnership prior to the Merger:

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

General Questions and Answers

         Set forth below are questions that you, as a Unitholder, may have regarding the Merger Proposal, the Adjournment Proposal and the Special Meeting, and brief answers to those questions. You are urged to read carefully this proxy statement and the other documents referred to in this proxy statement in their entirety, including the Merger Agreement, which is attached as Annex A to this proxy statement, and the documents incorporated by reference into this proxy statement, because this section may not provide all of the information that is important to you with respect to the Merger and the Special Meeting. You may obtain a list of the documents incorporated by reference into this proxy statement in the section titled "Where You Can Find More Information."

Q:    Why am I receiving this proxy statement?

A:

The Partnership and the General Partner, together with TLP Holdings, Equity Holdings, Parent and Merger Sub have agreed to a merger, pursuant to which Merger Sub will merge with and into the Partnership, with the Partnership surviving as a wholly owned subsidiary of Parent and the General Partner, each of whom are indirect controlled subsidiaries of ArcLight. After the Merger, the Partnership's Common Units will cease to be publicly traded. In order to complete the Merger, the holders of a majority of the issued and outstanding Common Units must vote to approve the Merger Agreement and the Merger. The Partnership is holding a special meeting of its Unitholders to obtain the Unitholder Approval.

This document is being delivered to you as a proxy statement by which the GP Board is soliciting proxies from you to vote on the approval of the Merger Agreement and the Merger at the Special Meeting or at any adjournment or postponement of the Special Meeting.

Your vote is extremely important, and we encourage you to submit your proxy as soon as possible. For more information on how to vote, please see the section of this proxy statement entitled " The Special Meeting ."

Q:    What will happen in the Merger?

A:

In the Merger, Merger Sub will merge with and into the Partnership. The Partnership will survive as a wholly owned subsidiary of Parent and the General Partner. If the Merger is completed, the Common Units will cease to be listed on the NYSE, will be deregistered under the Exchange Act, and will cease to be publicly traded.

Q:    What will I receive in the Merger for my Common Units?

A:

If the Merger is completed, each Common Unit held by Unaffiliated Unitholders will be converted into the right to receive $41.00 in cash, to be paid without interest and reduced by any applicable tax withholding. In addition, until the closing of the Merger, Unitholders will continue to receive regular quarterly distributions of $0.805 per Common Unit with respect to any completed quarter prior to closing, regardless of whether the closing occurs prior to or after the applicable record date.

Q:    How does the $41.00 per Common Unit base Merger Consideration compare to the market price of the Common Units prior to the execution of the Merger Agreement?

A:

The Merger Consideration represents a 12.6% premium to the $36.40 closing price per Common Unit on November 23, 2018, the last trading day before the announcement of the Merger.

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Q:    How will I receive the Merger Consideration to which I am entitled?

A:

Promptly after the Effective Time, the paying agent will mail or provide to each holder of record of Common Units certain transmittal materials and instructions for use in effecting the surrender of Common Units to the paying agent.

Q:    What happens if the Merger is not completed?

A:

If the Merger Agreement is not approved by Unitholders or if the Merger is not completed for any other reason, Unitholders will not receive any form of consideration for their Common Units in connection with the Merger. Instead, the Partnership will remain a publicly traded limited partnership and the Common Units will continue to be listed and traded on the NYSE.

Q:    Will the Partnership continue to pay quarterly distributions for completed calendar quarters prior to the completion of the Merger?

A:

Yes. Under the Merger Agreement, the General Partner shall declare, and cause the Partnership to pay, a regular cash distribution to Unitholders (including the Unaffiliated Unitholders) for each completed calendar quarter ending prior to the Effective Time in an amount equal to $0.805 per Common Unit per calendar quarter completed. If a record date for a distribution with respect to any completed calendar quarter has not occurred prior to the Effective Time, the distribution shall be payable to the Unitholders as part of the Merger Consideration. The Partnership will not pay any cash distributions to Unitholders for partially completed calendar quarters prior to the Effective Time or any distributions with respect to periods ending after the Effective Time.

Q:    What am I being asked to vote on?

A:

Unitholders are being asked to vote on the following proposals:

•

Merger Proposal:   To approve the Merger Agreement, a copy of which is attached as Annex A to this proxy statement, as such agreement may be amended from time to time, and the Merger; and

•

Adjournment Proposal:   To approve the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting.

The approval of the Merger Proposal by Unitholders holding at least a majority of outstanding Common Units is a condition to the obligations of the Partnership and Parent to complete the Merger. The approval of the Adjournment Proposal is not a condition to the obligations of the Partnership or Parent to complete the Merger.

Q:    Does the GP Board recommend that Unitholders approve the Merger Agreement and the Merger?

A:

Yes. The GP Board, after considering various factors, including the unanimous determination and recommendation of the Conflicts Committee, has determined that the Merger Agreement and the Merger are in the best interests of the Partnership and the Unaffiliated Unitholders. Therefore, the GP Board recommends that you vote "FOR" the proposal to approve the Merger Agreement and the Merger, at the Special Meeting. See " Special Meeting—Recommendation of the Conflicts Committee and the GP Board; Reasons for Recommending Approval of the Merger Proposal " beginning on page 38 of this proxy statement. In considering the recommendation of the GP Board with respect to the Merger Agreement and the transactions contemplated thereby, including the Merger, you should be aware that directors and executive officers of the General Partner have interests in the Merger that may be different from, or in addition to, your interests as a Unitholder. You should consider these interests in voting on the Merger Proposal. These different

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interests are described under " Special Meeting—Interests of the Directors and Executive Officers of the General Partner in the Merger " beginning on page 63 of this proxy statement.

Q:    Will the Partnership be required to submit the Merger Proposal to the Unitholders even if the Conflicts Committee has effected a Partnership Adverse Recommendation Change with respect to the approval of the Merger Agreement?

A:

Yes. Unless the Merger Agreement is terminated, the Partnership is required to submit the Merger Proposal to the Unitholders regardless of whether the Conflicts Committee recommends that the Unitholders reject the Merger Proposal or otherwise takes any action constituting an adverse recommendation change under the Merger Agreement.

For more information regarding the ability of the Partnership to terminate the Merger Agreement, and the Conflicts Committee's ability to change its recommendation with respect to the Merger Proposal, see " Proposal No. 1. The Merger Agreement—Termination of the Merger Agreement " beginning on page 79 of this proxy statement and " Proposal No. 1. The Merger Agreement—Change in the GP Board Recommendation " beginning on page 76 of this proxy statement.

Q:    What Unitholder vote is required for the approval of each proposal?

A:

The following are the vote requirements for the proposals:

•

Merger Proposal.   The affirmative vote of holders of at least a majority of the issued and outstanding Common Units. Abstentions and unvoted Common Units will have the same effect as votes "AGAINST" the Merger Proposal.

•

Adjournment Proposal.   If a quorum is present at the Special Meeting, the affirmative vote of holders of at least a majority of the issued and outstanding Common Units; provided that, if a quorum is not present at the Special Meeting, the affirmative vote of holders of a majority of the issued and outstanding Common Units entitled to vote at such meeting represented either in person or by proxy, will be required to approve the proposal. Abstentions and unvoted Common Units of attendees entitled to vote at such meeting will have the same effect as votes "AGAINST" the Adjournment Proposal.

Q:    How do TLP Holdings and Equity Holdings intend to vote?

A:

As of the close of business on                , 2019, the record date for the Special Meeting, TLP Holdings and Equity Holdings collectively owned                         Common Units, representing        % of the outstanding Common Units entitled to vote at the Special Meeting.

Pursuant to the Support Agreement entered into in connection with entry into the Merger Agreement and included as Annex C to this proxy statement, TLP Holdings and Equity Holdings have agreed to appear at the Special Meeting and either vote, in person or by proxy, all of their Common Units in favor of the Merger Agreement and the transactions contemplated thereby, including the Merger.

Q:    What constitutes a quorum for the Special Meeting?

A:

At least a majority of the outstanding Common Units must be represented in person or by proxy at the Special Meeting in order to constitute a quorum. Pursuant to the Support Agreement included as Annex C to this proxy statement, TLP Holdings and Equity Holdings have agreed to appear at the Special Meeting for quorum purposes.

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Q:    When is this proxy statement being mailed?

A:

This proxy statement and the proxy card are first being sent to Unitholders on or about                        , 2019. Only one proxy statement will be delivered to multiple Unitholders sharing an address, unless the Partnership has received contrary instructions from one or more of the Unitholders.

Q:    What is a proxy?

A:

A proxy is your legal designation of another person to vote your Common Units. This written document describing the matters to be considered and voted on at the Special Meeting is called a proxy statement. The document used to designate a proxy to vote your Common Units is called a proxy card, a form of which is attached as Annex D hereto.

Q:    Who will solicit and pay the cost of soliciting proxies?

A:

The Partnership has engaged Georgeson LLC ("Georgeson") to assist in the solicitation of proxies for the Special Meeting. Georgeson will be paid approximately $10,000, plus reasonable out-of-pocket expenses, by the Partnership for these and other advisory services in connection with the Special Meeting. In addition, the Partnership has agreed to indemnify Georgeson, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses.

Forms of proxies and proxy materials may also be distributed through brokers, banks and other nominees to the beneficial owners of Common Units, in which case these parties will be reimbursed for their reasonable out-of-pocket expenses.

Q:    When and where is the Special Meeting?

A:

The Special Meeting will be held at            , on            , 2019, at            (local time).

Q:    How do I vote my Common Units at the Special Meeting or submit my proxy?

A:

There are four ways you may cast your vote or cause your Common Units to be voted.

•

In Person.   If you are a Unitholder of record, you may vote in person at the Special Meeting. Common Units held by a broker, bank or other nominee may be voted in person by you only if you obtain a legal proxy from the record holder (which is your broker, bank or other nominee) giving you the right to vote Common Units;

•

Via the Internet.   You may submit your proxy electronically via the Internet by accessing the Internet address provided on each proxy card (if you are a Unitholder of record) or voting instruction card (if your Common Units are held by a broker, bank or other nominee);

•

By Telephone.   You may submit your proxy by using the toll-free telephone number listed on the enclosed proxy card (if you are a Unitholder of record) or voting instruction card (if your Common Units are held by a broker, bank or other nominee); or

•

By Mail.   You may submit your proxy by filling out, signing and dating the enclosed proxy card (if you are a Unitholder of record) or voting instruction card (if your Common Units are held by a broker, bank or other nominee) and returning it by mail in the prepaid envelope provided.

Even if you plan to attend the Special Meeting in person, you are encouraged to submit your proxy as described above so that your vote will be counted if you later decide not to attend the Special Meeting.

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If your Common Units are held by a broker, bank or other nominee, also known as holding units in "street name," you should receive instructions from the broker, bank or other nominee that you must follow in order to have your Common Units voted. Please review such instructions to determine whether you will be able to vote via the Internet or by telephone. The deadline for submitting your proxy by telephone or electronically through the Internet is 11:59 p.m. Eastern Time on                        , 2019 (the "telephone/internet deadline"). If the Special Meeting is adjourned to solicit additional votes in favor of the Merger Proposal, the deadline for submitting your proxy by telephone or electronically through the Internet deadline may be extended. The failure to instruct your bank, brokerage firm or other nominee to vote your Common Units "FOR" approval of the Merger Proposal will have the same effect as voting "AGAINST" approval of the Merger Proposal.

Q:    Where can I find the voting results of the Special Meeting?

A:

The preliminary voting results are expected to be announced at the Special Meeting. In addition, promptly following the conclusion of the Special Meeting, the Partnership intends to furnish the final voting results with the SEC on a Current Report on Form 8-K.

Q:    If my Common Units are held in "street name" by my broker, will my broker automatically vote my Common Units for me?

A:

No. If your Common Units are held in an account at a broker or through another nominee, you must instruct the broker or other nominee on how to vote your Common Units by following the instructions that the broker or other nominee provides to you with these materials. Most brokers offer the ability for Unitholders to submit voting instructions by mail by completing a voting instruction card, by telephone and via the Internet.

If you do not provide voting instructions to your broker, your Common Units will not be voted on any proposal on which your broker does not have discretionary authority to vote. This is referred to in this proxy statement and in general as a broker non-vote. In these cases, the broker can register your Common Units as being present at the Special Meeting for purposes of determining a quorum, but will not be able to vote on those matters for which specific authorization is required. Under the current rules of the NYSE, brokers do not have discretionary authority to vote on any of the Proposals, including the Merger Proposal. A broker non-vote will have the same effect as a vote "AGAINST" the Merger Proposal and the Adjournment Proposal.

Q:    How will my Common Units be represented at the Special Meeting?

A:

If you submit your proxy by telephone, the Internet website or by signing and returning your proxy card, the officers named in your proxy card will vote your Common Units in the manner you requested if you correctly submitted your proxy. If you sign your proxy card and return it without indicating how you would like to vote your Common Units, your proxy will be voted as the GP Board recommends, which is:

•

Merger Proposal:   "FOR" the approval of the Merger Agreement and the Merger; and

•

Adjournment Proposal:   "FOR" the approval of the adjournment of the Special Meeting (unless you also indicate to vote against the approval of the Merger Agreement and the Merger), if necessary to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting.

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Q:    Who may attend the Special Meeting?

A:

Unitholders (or their authorized representatives) and the Partnership's invited guests may attend the Special Meeting. All attendees at the Special Meeting should be prepared to present government-issued photo identification (such as a driver's license or passport) for admittance.

Q:    Is my vote important?

A:

Yes, your vote is very important. If you do not submit a proxy or vote in person at the Special Meeting, it will be more difficult for the Partnership to obtain the necessary quorum to hold the Special Meeting. In addition, an abstention or your failure to submit a proxy or to vote in person will have the same effect as a vote "AGAINST" the approval of the Merger Agreement and the Merger. If you hold your Common Units through a broker or other nominee, your broker or other nominee will not be able to cast a vote on such approval without instructions from you. The GP Board recommends that Unitholders vote "FOR" the Merger Proposal.

Q:    Can I revoke my proxy or change my voting instructions?

A:

Yes. If you are a Unitholder of record, you may revoke your proxy or change your voting instructions at any time before the telephone/internet deadline or before the polls close at the Special Meeting by:

•

sending a written notice, no later than the telephone/internet deadline, to TransMontaigne Partners L.P. at 1670 Broadway, Suite 3100, Denver, Colorado 80202, Attention: Secretary, that bears a date later than the date of your proxy and is received prior to the Special Meeting and states that you revoke your proxy;

•

submitting a valid, later-dated proxy by mail, telephone or Internet that is received prior to the Special Meeting; or

•

attending the Special Meeting and voting by ballot in person (your attendance at the Special Meeting will not, by itself, revoke any proxy that you have previously given).

If you hold your Common Units through a broker or other nominee, you must follow the directions you receive from your broker or other nominee in order to revoke your proxy or change your voting instructions.

Only your last submitted proxy will be considered. Please cast your vote " FOR " each of the proposals listed in this proxy statement, following the instructions provided, as promptly as possible.

Q:    What happens if I sell my Common Units after the record date but before the Special Meeting?

A:

The record date for the Special Meeting is earlier than the date of the Special Meeting and earlier than the date that the Merger is expected to be completed. If you sell or otherwise transfer your Common Units after the record date but before the date of the Special Meeting, you will retain your right to vote at the Special Meeting. However, you will not have the right to receive the Merger Consideration to be received by the Unitholders in the Merger. In order to receive the Merger Consideration, you must hold your Common Units up to the completion of the Merger.

Q:    What does it mean if I receive more than one proxy card or voting instruction card?

A:

Your receipt of more than one proxy card or voting instruction card may mean that you have multiple accounts with the Partnership's transfer agent or with a brokerage firm, bank or other nominee. If submitting your proxy or providing voting instructions by mail, please sign and return all proxy cards or voting instruction cards to ensure that all of your Common Units are voted.

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Each proxy card or voting instruction card represents a distinct number of Common Units, and it is the only means by which those particular Common Units may be voted by proxy.

Q:    Am I entitled to appraisal rights if I vote against the approval of the Merger Proposal?

A:

No. Appraisal rights are not available in connection with the Merger under the Partnership Agreement or the laws of Delaware.

Q:    Is completion of the Merger subject to any conditions?

A:

Yes. In addition to the receipt of Unitholder Approval, completion of the Merger requires the receipt of the necessary governmental clearances and the satisfaction or, to the extent permitted by applicable law, waiver of the other conditions specified in the Merger Agreement. For further discussion of the conditions to the Merger, see " The Merger Agreement—Conditions to Consummation of the Merger ."

Q:    When do you expect to complete the Merger?

A:

The Partnership and Parent are working towards completing the Merger promptly. The Partnership and Parent currently expect to complete the Merger in the first quarter of 2019, subject to receipt of Unitholder Approval, regulatory approvals and clearances and other usual and customary closing conditions. However, no assurance can be given as to when, or if, the Merger will occur.

Q:    What are the material U.S. federal income tax consequences of the Merger to the Unitholders?

A:

If you are a U.S. Unitholder (as defined in the section titled "Material U.S. Federal Income Tax Consequences"), the receipt of cash in exchange for Common Units pursuant to the Merger will be a taxable transaction for U.S. federal income tax purposes and the resulting tax liability, if any, will depend on your particular situation. Accordingly, you should consult your tax advisors regarding the particular tax consequences to you of the exchange of Common Units for cash pursuant to the Merger in light of your particular circumstances (including the application and effect of any state, local or foreign income and other tax laws).

Q:    What do I need to do now?

A:

Carefully read and consider the information contained in and incorporated by reference into this proxy statement, including its annexes. Then, please submit your proxy for your Common Units in accordance with the instructions described above.

If you hold Common Units through a broker or other nominee, please instruct your broker or nominee to submit your proxy for your Common Units by following the instructions that the broker or nominee provides to you with these materials.

Q:    Should I send in my evidence of ownership now?

A:

No. After the Merger is completed, you will be sent a letter of transmittal with detailed written instructions for exchanging your Common Units for the Merger Consideration. If your Common Units are held in "street name" by your broker, bank or other nominee, you may receive instructions from your broker, bank or other nominee as to what action, if any, you need to take to effect the surrender of your "street name" Common Units in exchange for the Merger Consideration.

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Q:    What is householding and how does it affect me?

A:

We have adopted a procedure approved by the SEC called "householding." Under this procedure, Unitholders who have the same address and have consented to our mailing of proxy materials and other unitholder information only to one account in such household will receive only one paper copy of the proxy materials, as applicable, unless one or more of these Unitholders notifies us that they wish to continue receiving individual copies. This procedure helps reduce our printing costs and postage fees.

A number of brokerage firms with account holders who are Unitholders may also use householding. Once you have received notice from your bank or broker that it will be householding materials to your address, householding generally will continue until you are notified otherwise or until you revoke your consent.

If, at any time, you no longer wish to participate in "householding" and you prefer to receive separate proxy materials, please notify your broker or write to the following address:

TransMontaigne Partners L.P.
1670 Broadway, Suite 3100
Denver, Colorado 80202
Attention: Secretary
Phone: (303) 626-8200

For further discussion of householding matters, see " Other Matters—Householding of Special Meeting Materials ."

Q:    Who should I call with questions?

A:

Unitholders should call Georgeson, the Partnership's proxy solicitor, at (888) 642-8066 (Toll Free) , with any questions about the Merger or the Special Meeting, or to obtain additional copies of this proxy statement, proxy cards or voting instruction forms.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This proxy statement and the other documents referred to or incorporated by reference into this proxy statement include certain forward-looking statements regarding, among other things, the Partnership's plans, strategies and prospects, both business and financial.

        Forward-looking statements give the Partnership's current expectations, contain projections of results of operations or of financial condition, or forecasts of future events. When used in this proxy statement, the words "could," "may," "should," "will," "seek," "believe," "expect," "anticipate," "intend," "continue," "estimate," "plan," "target," "predict," "project," "attempt," "is scheduled," "likely," "forecast," the negatives thereof and other similar expressions are used to identify forward-looking statements, although not all forward-looking statements contain such identifying words. These forward-looking statements are based on our current expectations and assumptions about future events and are based on currently available information as to the outcome and timing of future events. You are cautioned not to place undue reliance on any forward-looking statements. Although the Partnership believes that the expectations reflected in such forward-looking statements are based on reasonable assumptions, such statements are subject to risks and uncertainties that could cause actual results to differ materially from those projected. Further, the Partnership's ability to consummate the proposed Merger may be influenced by many factors that are difficult to predict, involve uncertainties that may materially affect actual results and that are often beyond the control of the Partnership. These factors include, but are not limited to, the occurrence of any event, change or other circumstance that could give rise to termination of the Merger Agreement, the failure of closing conditions, and delays in the consummation of the proposed transaction, as circumstances warrant; the impact of the announcement of the proposed Merger on relationships with third parties, including commercial counterparties, employees and competitors, and risks associated with the loss and ongoing replacement of key personnel; large customer defaults; interest rates; operating hazards, natural disasters, weather-related delays, casualty losses and other matters beyond the Partnership's control; uncertainty regarding the Partnership's future operating results; changes in tax status of the Partnership; effects of existing and future laws and governmental regulations; and the effects of future litigation, including litigation relating to the Merger. Important factors that could cause actual results to differ materially from the Partnership's expectations and may adversely affect the Partnership's business and results of operations are disclosed in "Item 1A. Risk Factors" in the Partnership's Annual Report on Form 10-K for the year ended December 31, 2017, filed with the SEC on March 15, 2018, as updated and supplemented by subsequent filings with the SEC. The forward looking statements speak only as of the date made, and, other than as may be required by law, the Partnership undertakes no obligation to update or revise any forward looking statements, whether as a result of new information, future events or otherwise.

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PARTIES TO THE MERGER
TRANSMONTAIGNE PARTNERS L.P.
1670 Broadway, Suite 3100
Denver, Colorado 80202
Phone: (303) 626-8200

        The Partnership is a terminaling and transportation company with assets and operations in the United States along the Gulf Coast, in the Midwest, in Houston and Brownsville, Texas, along the Mississippi and Ohio Rivers, in the Southeast and on the West Coast. The Partnership provides integrated terminaling, storage, transportation and related services for customers engaged in the distribution and marketing of light refined petroleum products, heavy refined petroleum products, crude oil, chemicals, fertilizers and other liquid products. The Partnership's Common Units are listed on the New York Stock Exchange (the "NYSE") under the ticker symbol "TLP."

TRANSMONTAIGNE GP L.L.C.
1670 Broadway, Suite 3100

Denver, Colorado 80202
Phone: (303) 626-8200

        The General Partner is the general partner of the Partnership. The GP Board and the executive officers of the General Partner manage the Partnership. The General Partner is a direct wholly owned subsidiary of TLP Holdings.

TLP FINANCE HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        Parent is a direct wholly owned subsidiary of TLP Holdings. Parent has not carried on any activities or operations to date, except for those activities incidental to its formation on October 16, 2017 and undertaken in connection with the transactions contemplated by the Merger Agreement.

TLP MERGER SUB, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        Merger Sub is a direct wholly owned subsidiary of Parent formed solely for the purpose of facilitating the Merger. Merger Sub has not carried on any activities or operations to date, except for those activities incidental to its formation and undertaken in connection with the transactions contemplated by the Merger Agreement. By operation of the Merger, Merger Sub will be merged with and into the Partnership, with the Partnership surviving the Merger as a wholly owned subsidiary of Parent and the General Partner.

TLP ACQUISITION HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        TLP Holdings is an indirect subsidiary of and controlled by ArcLight. TLP Holdings is a direct wholly owned subsidiary of PPH Management Holdings, LLC, a Delaware limited liability company, which is a direct, controlled subsidiary of Pike Holdings. Pike Petroleum Fund VI, LLC, a Delaware

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limited liability company, owns approximately 54.0% of Pike Holdings, and is a direct wholly owned subsidiary of Pike Petroleum Holdings Fund VI Holdings, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of ArcLight.

TLP EQUITY HOLDINGS, LLC
c/o ArcLight Capital Holdings, LLC
200 Clarendon Street, 55th Floor
Boston, MA 02116
(617) 531-6300

        Equity Holdings is a direct wholly owned subsidiary of ArcLight.

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THE PARTNERSHIP SPECIAL UNITHOLDER MEETING

        The Partnership is providing this proxy statement to its Unitholders in connection with the solicitation of proxies to be voted at the Special Meeting of Unitholders that the Partnership has called for, among other things, the purpose of holding a vote upon a proposal to approve the Merger Agreement and the Merger, and any adjournment or postponement thereof. This proxy statement is first being mailed to Unitholders on or about            , 2019 and provides Unitholders with the information they need to know to be able to vote or instruct their vote to be cast at the Special Meeting of Unitholders.

Date, Time and Place of the Special Meeting

        The Special Meeting is scheduled to be held at                , on                , 2019, at                 a.m. (local time).

Matters to be Considered at the Special Meeting

        At the Special Meeting, Unitholders will be asked to consider and vote on the following proposals:

•

Merger Proposal.   To approve the Merger Agreement, a copy of which is attached as Annex A to this proxy statement, as such agreement may be amended from time to time, and the Merger; and



•

Adjournment Proposal.   To approve the adjournment of the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting.

Recommendation of the GP Board

        After considering various factors, including the unanimous determination by the Conflicts Committee that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders and recommendation of the Conflicts Committee that the GP Board and the Unitholders approve the Merger Agreement and the Merger, the GP Board unanimously determined that the Merger Agreement and the transactions contemplated by the Merger Agreement are in the best interests of the Partnership and the Unaffiliated Unitholders and has approved the Merger Agreement and the transactions contemplated thereby, including the Merger. The GP Board recommends that the Unitholders vote "FOR" the Merger Proposal and "FOR" the Adjournment Proposal.

        In considering the recommendation of the GP Board with respect to the Merger Agreement and the transactions contemplated thereby, including the Merger, you should be aware that some of the General Partner's directors and executive officers may have interests that are different from, or in addition to, the interests of the Unitholders more generally. See " Special Factors—Interests of the Directors and Executive Officers of the General Partner in the Merger ."

Who Can Vote at the Special Meeting

        The record date for the Special Meeting is                , 2019. Only Unitholders of record at the close of business on the record date will be entitled to receive notice of and to vote at the Special Meeting or any adjournment or postponement of the meeting unless adjournment shall be for more than 45 days, in which case the GP Board shall set a new record date.

        As of the close of business on the record date of                , 2019, there were                Common Units held by Unitholders outstanding and entitled to vote at the Special Meeting. Each holder of

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Common Units entitled to vote at the Special Meeting may cast one vote for each Common Unit that such holder owned on the close of business on the record date.

        A complete list of Unitholders entitled to vote at the Special Meeting will be available for inspection at the principal place of business of the Partnership during regular business hours for a period of no less than 10 days before the Special Meeting and at the place of the Special Meeting during the meeting.

Quorum

        A quorum of Unitholders represented in person or by proxy at the Special Meeting is required to vote on approval of the Merger Agreement at the Special Meeting, but not to vote on approval of any adjournment of the meeting. At least a majority of the outstanding Common Units must be represented in person or by proxy at the meeting in order to constitute a quorum. Any abstentions and broker non-votes will be considered to be present at the meeting for purposes of determining whether a quorum is present at the Special Meeting. Pursuant to the Support Agreement, included as Annex C to this proxy statement, TLP Holdings and Equity Holdings have agreed to appear at the Special Meeting for quorum purposes and to vote or cause their Common Units to be voted in favor of the Merger Agreement and the transactions contemplated thereby, including the Merger.

Vote Required for Approval

        The affirmative vote of holders of at least a majority of the issued and outstanding Common Units is required to approve the Merger Agreement and the Merger. As of the record date, there were                Common Units held by Unitholders outstanding. The affirmative vote of the Unaffiliated Unitholders representing approximately         % of the total issued and outstanding Common Units (in addition to the Common Units to be voted by TLP Holdings and Equity Holdings) is necessary to approve the Merger and the Merger Agreement.

        The affirmative vote of holders of at least a majority of the issued and outstanding Common Units is required to approve the adjournment of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement and the Merger, at the time of the Special Meeting if a quorum is present at the meeting; provided that, if a quorum is not present at the meeting, the affirmative vote of holders of a majority of the issued and outstanding Common Units entitled to vote at such meeting represented either in person or by proxy is required to approve the Adjournment Proposal.

        Abstentions will have the same effect as votes "AGAINST" approval of the Merger Proposal and if you fail to cast your vote in person or by proxy or fail to give voting instructions to your broker, bank or other nominee and are otherwise represented in person or by proxy, it will have the same effect as a vote "AGAINST" the Merger Proposal.

Common Unit Ownership of TLP Holdings and Equity Holdings

        At the close of business on the record date for the Special Meeting, TLP Holdings owned                Common Units and Equity Holdings owned                 Common Units, which collectively represent an aggregate of approximately            % of the outstanding Common Units.

Voting of Common Units by Holders of Record

        If you are entitled to vote at the Special Meeting and hold your Common Units in your own name, you can submit a proxy or vote in person by completing a ballot at the Special Meeting. However, the Partnership encourages you to submit a proxy before the Special Meeting even if you plan to attend the Special Meeting in order to ensure that your Common Units are voted. A proxy is a legal designation

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of another person to vote your Common Units on your behalf. If you hold Common Units in your own name, you may submit a proxy for your Common Units by:

•

accessing the Internet website specified on the enclosed proxy card and following the instructions provided to you;



•

calling the toll-free number specified on the enclosed proxy card and following the instructions when prompted; or



•

filling out, signing and dating the enclosed proxy card and mailing it in the prepaid envelope included with these proxy materials.

        When a Unitholder submits a proxy by telephone or through the Internet, such Unitholder's proxy is recorded immediately. The Partnership encourages its Unitholders to submit their proxies using these methods whenever possible. If you submit a proxy by telephone or the Internet website, please do not return your proxy card by mail unless you wish to change your vote in a manner compliant with the voting guidelines set forth in this proxy statement.

        All Common Units represented by each properly executed and valid proxy received before the Special Meeting will be voted in accordance with the instructions given on the proxy. If a Unitholder executes a proxy card without giving instructions, the Common Units represented by that proxy card will be voted as the GP Board recommends. The GP Board recommends that Unitholders vote "FOR" the Merger Proposal and "FOR" the Adjournment Proposal.

        Your vote is important. Accordingly, please submit your proxy by telephone, through the Internet or by mail, whether or not you plan to attend the meeting in person. Proxies must be received by 11:59 p.m. (local time), on                , 2019.

Voting of Common Units Held in Street Name

        If your Common Units are held in an account at a broker or through another nominee, you must instruct the broker or other nominee on how to vote your Common Units by following the instructions that the broker or other nominee provides to you with these proxy materials. Most brokers offer the ability for Unitholders to submit voting instructions by mail by completing a voting instruction card, by telephone and via the Internet.

        If you do not provide voting instructions to your broker, your Common Units will not be voted on any proposal on which your broker does not have discretionary authority to vote. This is referred to in this proxy statement and in general as a broker non-vote. In these cases, the broker or other nominee can register your Common Units as being present at the Special Meeting for purposes of determining a quorum, but will not be able to vote your Common Units on those matters for which specific authorization is required. Under the current rules of the NYSE, brokers do not have discretionary authority to vote on any of the Proposals, including the Merger Proposal. A broker non-vote of a Common Unit will have the same effect as a vote "AGAINST" the Merger Proposal and the Adjournment Proposal.

        If you hold Common Units through a broker or other nominee and wish to vote your Common Units in person at the Special Meeting, you must obtain a proxy from your broker or other nominee and present it to the inspector of election with your ballot when you vote at the Special Meeting.

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Revocability of Proxies; Changing Your Vote

        You may revoke your proxy and/or change your voting instructions at any time before your proxy is voted at the Special Meeting. If you are a Unitholder of record, you can do this by:

•

sending a written notice, no later than the telephone/internet deadline, to TransMontaigne Partners L.P. at 1670 Broadway, Suite 3100, Denver, Colorado 80202, Attention: Secretary, that bears a date later than the date of your proxy and is received prior to the Special Meeting and states that you revoke your proxy;



•

submitting a valid, later-dated proxy by mail, telephone or Internet that is received prior to the Special Meeting; or



•

attending the Special Meeting and voting by ballot in person (your attendance at the Special Meeting will not, by itself, revoke any proxy that you have previously given).

        If you hold your Common Units through a broker or other nominee, you must follow the directions you receive from your broker or other nominee in order to revoke your proxy or change your voting instructions.

Solicitation of Proxies

        This proxy statement is furnished in connection with the solicitation of proxies by the GP Board to be voted at the Special Meeting. The Partnership has engaged Georgeson to assist in the solicitation of proxies for the meeting and the Partnership estimates it will pay Georgeson a fee of approximately $10,000, plus reasonable out-of-pocket expenses, for these and other advisory services. The Partnership has also agreed to indemnify Georgeson, its subsidiaries and their respective directors, officers, employees and agents against certain claims, liabilities, losses, damages and expenses. In addition, the Partnership may reimburse brokerage firms and other persons representing beneficial owners of Common Units for their reasonable expenses in forwarding solicitation materials to such beneficial owners. Proxies may also be solicited by certain of the General Partner's directors, officers and employees by telephone, electronic mail, letter, facsimile or in person, but no additional compensation will be paid to them.

        A letter of transmittal and instructions for the surrender of Common Units will be mailed to holders of such Common Units shortly after the completion of the Merger.

Adjournments

        Adjournments may be made for the purpose of, among other things, soliciting additional proxies. To approve an adjournment if a quorum is present, holders of at least a majority of the outstanding Common Units must vote in favor of the proposal. To approve an adjournment if a quorum is not present, holders of at least a majority of the outstanding Common Units entitled to vote at such meeting that are represented either in person or by proxy at such meeting must vote in favor of the proposal. The Partnership is not required to notify holders of Common Units of any adjournment of 45 days or less if the time and place of the adjourned meeting are announced at the meeting at which the adjournment is taken, unless after the adjournment a new record date is fixed for the adjourned meeting. At any adjourned meeting, the Partnership may transact any business that it might have transacted at the original Special Meeting, provided that a quorum is present at such adjourned meeting. Proxies submitted by holders of Common Units for use at the original Special Meeting will be used at any adjournment or postponement of the meeting. References to the Special Meeting in this proxy statement are to such Special Meeting as adjourned or postponed.

Assistance

        If you need assistance in completing your proxy card or have questions regarding the Special Meeting, please contact Georgeson toll-free at (888)  642-8066 .

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SPECIAL FACTORS

        This section of the proxy statement describes the material aspects of the proposed Merger. This section may not contain all of the information that is important to you. You should carefully read this entire proxy statement and the documents incorporated herein by reference, including the full text of the Merger Agreement, for a more complete understanding of the Merger. A copy of the Merger Agreement is attached as Annex A hereto. In addition, important business and financial information about the Partnership is included in or incorporated into this proxy statement by reference. See " Where You Can Find More Information ."

Effect of the Merger and the Merger

        Subject to the terms and conditions of the Merger Agreement and in accordance with the laws of the State of Delaware, the Merger Agreement provides for the merger of the Merger Sub with and into the Partnership. The Partnership, which is sometimes referred to following the Merger as the surviving entity, will survive the Merger, and the separate limited liability company existence of Merger Sub will cease. As a result of the Merger, the Partnership will survive as a wholly owned subsidiary of Parent and the General Partner. After the completion of the Merger, the certificate of limited partnership of the Partnership in effect immediately prior to the Effective Time will be the certificate of limited partnership of the surviving entity, until amended in accordance with its terms and applicable law, and the Partnership Agreement in effect immediately prior to the Effective Time will be amended and restated and as so amended and restated, shall be the agreement of limited partnership of the surviving entity from and after the Effective Time, until amended in accordance with its terms and applicable law.

        The Merger Agreement provides that, at the Effective Time, each Common Unit issued and outstanding or deemed issued and outstanding as of immediately prior to the Effective Time and held by Unaffiliated Unitholders will be converted into the right to receive $41.00 in cash, to be paid without interest and reduced by any applicable tax withholding. In addition, until the closing of the Merger, the Unitholders will continue to receive regular quarterly distributions of $0.805 per Common Unit with respect to any completed quarter prior to closing, regardless of whether the closing occurs prior to or after the applicable record date.

        Each of the Partnership's phantom units under the Equity Plans will be converted into a right to receive a cash payment in an amount equal to the Merger Consideration with respect to each such phantom unit, which amount (i) will be treated as "Covered Compensation" under the Savings and Retention Plan, vest and be payable in accordance with the terms of the underlying award agreement or letter (or the Savings and Retention Plan, if there is no separate award agreement or letter), and (ii) will be adjusted from and after the Effective Time in accordance with the Savings and Retention Plan.

        The IDRs issued and outstanding immediately prior to the Effective Time will be converted into 100 Common Units, which Common Units shall be unchanged and remain outstanding following the Merger. As of the Effective Time, all IDRs will no longer be outstanding and will automatically be cancelled and cease to exist, and no consideration will be delivered in respect thereof.

        Each of the Partnership's general partner units issued and outstanding immediately prior to the Effective Time will be converted into (i) one Common Unit, which Common Unit will be unchanged and remain outstanding following the Merger, and (ii) in aggregate, a non-economic general partner interest in the surviving entity. As of the Effective Time, all of the Partnership's general partner units converted into the right to receive the Common Units and a noneconomic general partner interest will no longer be outstanding and will automatically be cancelled and cease to exist, and no consideration will be delivered in respect thereof. See " Proposal No. 1. The Merger Agreement " for further information.

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        The Partnership's net book value (calculated as total assets minus total liabilities) as of December 31, 2017 was approximately $364,217,000, and the Partnership's net earnings for the fiscal year ended December 31, 2017 was $48,493,000. As of December 31, 2017, the Sponsor Entities beneficially owned or controlled approximately 19.5% of the Partnership's outstanding Common Units (as TLP Holdings owned approximately 4.9% of the Common Units and Equity Holdings owned approximately 14.6% of the Common Units), representing an effective beneficial ownership by the Sponsor Entities as of December 31, 2017, of 19.5% of the Partnership's net book value attributable to such Common Units and, in combination with TLP Holdings also indirectly owning the 2% general partner interest in the Partnership and 100% of the Partnership's outstanding IDRs, net income attributable to around 41% of the Partnership's net earnings for the fiscal year ended December 31, 2017 ($19,715,000). If the Merger is consummated, the Sponsor Entities' aggregate beneficial interest in the Partnership's net book value will increase to 100% and net earnings will increase to 100%. Accordingly, if the Merger is consummated, the Sponsor Entities' aggregate beneficial interest in the Partnership's net book value and net earnings will increase to approximately $364,217,000 and $48,493,000, respectively (based on the Partnership's December 31, 2017 financial data), and the Sponsor Entities will have an indirect beneficial interest in the Partnership's net book value and net income attributable to owners in proportion to such person or entity's beneficial ownership interest in the Partnership. Parent and its affiliates will also be entitled to any future increase in the Partnership's value and all income generated by the Partnership's operations going forward.

Background of the Merger

        TLP Holdings acquired its interest in the General Partner from NGL Energy Partners LP on February 1, 2016. That transaction did not involve the acquisition of any publicly held Common Units by ArcLight or any of its owned or controlled subsidiaries, but through subsequent acquisitions, Equity Holdings acquired 2,366,704 Common Units (representing approximately 14.6% of the Common Units) and TLP Holdings acquired 800,000 Common Units (representing approximately 4.9% of the Common Units). As a result of these acquisitions, the Sponsor Entities own or control 100% of the Partnership's general partner interest, 100% of the IDRs and approximately 19.5% of the Common Units. The Partnership is controlled by the General Partner. TLP Holdings is the sole owner of the General Partner and has the right to appoint the entire GP Board, including the independent directors appointed in accordance with the listing standards of the NYSE.

        The Sponsor Entities, the GP Board and the senior management team of the General Partner regularly review operational and strategic opportunities to maximize value for their respective investors. In connection with these reviews, the parties from time to time evaluate potential transactions that would further their respective strategic objectives.

        Since May 2017, the landscape for master limited partnerships ("MLPs") has changed considerably. The Tax Cuts and Jobs Act lowered the U.S. federal corporate income tax rate from 35% to 21%, reducing the benefit of an MLP pass-through structure. In addition, the U.S. Federal Energy Regulatory Commission disallowed MLPs from receiving an income tax allowance on pipelines with tolling fees set under the "cost of service" framework. Although the Partnership was not directly impacted by the disallowance, many MLPs were, and the ruling either had or coincided with a negative impact on investments in MLPs in general. Between TLP Holdings' acquisition of the General Partner on February 1, 2016 and November 23, 2018 (the last trading day before the Merger was announced), the Alerian MLP Index, a leading gauge of energy MLPs whose constituents represent approximately 75% of total energy MLP market capitalization, declined by approximately 3.6%. These negative market trends have contributed to a significant number of MLPs eliminating their incentive distribution rights, directly or through mergers with the entities holding their incentive distribution rights, converting to corporations (for income tax and state law purposes) or both.

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        In light of the general MLP landscape, in mid-May 2018, an affiliate of ArcLight engaged Kirkland & Ellis LLP ("Kirkland") to provide advice regarding a potential strategic transaction involving the Sponsor Entities' investment in the Partnership, including organic growth projects, related party or third party acquisitions and a sponsor take private transaction. An affiliate of ArcLight also contacted Barclays Capital Inc. ("Barclays") to assist with the review and evaluation of such strategic alternatives. Over the next several weeks, the Sponsor Entities, Kirkland and Barclays discussed various strategic alternatives related to the Partnership, and the Sponsor Entities and Partnership management prepared a preliminary diligence presentation and financial model to be used by the Sponsor Entities and the Partnership to discuss potential strategic alternatives.

        On May 14, 2018, a representative of ArcLight contacted Barry Welch, the Chairman of the Conflicts Committee, and informed him that the Sponsor Entities were considering evaluating potential strategic transactions involving the Partnership, including a sponsor take private transaction. Following such discussion, Mr. Welch contacted a representative of RLF, which had previously served as legal counsel to the Conflicts Committee in connection with prior unrelated matters. Based on RLF's experience with the Conflicts Committee and RLF's experience with public mergers and acquisitions, complex transactions involving publicly traded partnerships and representations of conflicts committees in general, the Conflicts Committee determined that RLF had the requisite expertise to provide high quality advice to the Conflicts Committee and determined to engage RLF as its legal counsel in connection with the evaluation of any potential strategic transaction, including a potential sponsor take private or similar transaction, that may be delegated to the Conflicts Committee for review. In addition, Mr. Welch contacted a representative of Evercore, which had previously served as financial advisor to the Conflicts Committee in connection with an unrelated matter, and asked Evercore to provide the Conflicts Committee with materials summarizing Evercore's experience with respect to transactions that are similar to a sponsor take private transaction and Evercore's relationships with ArcLight, the Partnership and their affiliates. Evercore provided such materials to the Conflicts Committee on May 16, 2018.

        On May 21, 2018, the Conflicts Committee met telephonically to discuss a potential strategic transaction, including a potential sponsor take private or similar transaction, with representatives of RLF in attendance. Mr. Welch reported on his recent discussions with a representative of ArcLight. The Conflicts Committee also received a presentation from RLF regarding its duties and responsibilities under Delaware law and the Partnership Agreement. There was discussion with respect to the process for considering a potential transaction and the potential engagement of a financial advisor to assist the Conflicts Committee with its review of such a transaction. The Conflicts Committee discussed Evercore's experience and qualifications and the work previously done by Evercore for the Conflicts Committee. The Conflicts Committee determined to schedule a meeting with Evercore to discuss Evercore's experience and qualifications.

        On May 24, 2018, the Conflicts Committee met telephonically with representatives of RLF and Evercore in attendance to evaluate Evercore's qualifications to act as the Conflicts Committee's financial advisor in connection with a potential transaction. During the interview the Conflicts Committee inquired as to Evercore's experience with respect to, among other types of transactions, "going private" or similar transactions, the experience of potential team members of Evercore, and Evercore's ability to meet timing demands. Evercore confirmed to the Conflicts Committee that it has no relationships or conflicts of interest that would prevent it from serving as an independent advisor to the Conflicts Committee. There was discussion among the Conflicts Committee and Evercore regarding Evercore's capabilities, expertise, and compensation expectations.

        On June 14, 2018, the Chief Executive Officer of the General Partner, Fred Boutin, contacted Mr. Welch and informed him that management expected that an affiliate of ArcLight would make a proposal to the Partnership with respect to a sponsor take private transaction involving the Partnership and asked the Conflicts Committee to organize itself to evaluate such a proposal in the event it was

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made. Mr. Boutin subsequently delivered a preliminary diligence presentation and financial model to the Conflicts Committee and offered to review the information with the Conflicts Committee and its advisors. The senior management team of the General Partner assisted RLF, Evercore, and Barclays regarding certain diligence matters as requested following June 14, 2018, including, with respect to the impact of the potential transaction, if any, with respect to (i) outstanding obligations of the Partnership and its subsidiaries, (ii) the Equity Plans, (iii) change of control provisions in employment or commercial agreements, if any, (iv) pending or threatened litigation, if any, (v) tax impacts of the potential transaction, if any, and (vi) SEC disclosure obligations and continuing Exchange Act filing obligations related to the Partnership's 6.125% senior unsecured notes due 2026, if any, following the closing of the potential transaction.

        On June 15, 2018, the Conflicts Committee met telephonically with representatives of RLF. Mr. Welch summarized his recent conversations with Mr. Boutin. The Conflicts Committee discussed process and timing matters for evaluating the diligence presentation and financial model.

        Between June 15, 2018 and June 21, 2018, Mr. Welch had discussions with representatives of ArcLight and Mr. Boutin regarding strategic alternatives, including to the extent an affiliate of ArcLight determined to make a proposal, the potential timing for such proposal.

        On June 21, 2018, the Conflicts Committee met telephonically with representatives of Evercore and RLF. Mr. Welch reported on his recent conversations with representatives of ArcLight and Mr. Boutin. Evercore also discussed with the Conflicts Committee the materials delivered to the Conflicts Committee by Mr. Boutin on June 14, 2018.

        On July 9, 2018, TLP Holdings delivered a non-binding offer (the "July 9th Offer") to the Conflicts Committee to acquire all of the issued and outstanding publicly held Common Units of the Partnership that are not directly owned by TLP Holdings in exchange for $38.00 in cash for each such Common Unit. The July 9th Offer stated that the transaction would be structured as a merger between the Partnership and a subsidiary of TLP Holdings. On July 10, 2018, TLP Holdings filed an amendment to its existing Schedule 13D and issued a press release announcing that it had made the July 9th Offer, and on July 11, 2018, the Partnership issued a press release announcing receipt of the July 9th Offer.

        On July 11, 2018, the Conflicts Committee held two telephonic meetings. Earlier in the day, the Conflicts Committee held a meeting with representatives of RLF. During the meeting, the Conflicts Committee and its advisors discussed matters related to the Merger, including that the Merger would require a Unitholder vote, the Partnership's disclosure obligations, the anticipated timing of the Merger, the scope of the Conflicts Committee's work, the role of management, the Partnership's press release announcing receipt of the July 9 ^th  Offer, the potential for litigation, and a draft of resolutions of the GP Board delegating authority to the Conflicts Committee to evaluate the Merger. The Conflicts Committee also discussed requests that had been made by certain Unitholders to share their perspectives on the Merger with the Conflicts Committee. Following discussion, the Conflicts Committee authorized RLF to coordinate with such Unitholders in order for their perspectives to be communicated to the Conflicts Committee. The Conflicts Committee also discussed the potential engagement of Evercore as its financial advisor. The Conflicts Committee determined that Evercore had the requisite expertise to provide high quality advice to the Conflicts Committee based on, among other factors, Evercore's prior experience with the Conflicts Committee and Evercore's experience with public mergers and acquisitions, complex transactions involving publicly traded partnerships and representations of conflicts committees in general. The Conflicts Committee determined to engage Evercore, subject to negotiation of a mutually acceptable fee and engagement letter. The terms of the Conflicts Committee's engagement with Evercore were confirmed by a letter agreed and accepted by the Partnership and the Conflicts Committee.

        Later in the day on July 11, 2018, the Conflicts Committee held a meeting with representatives of Evercore, RLF, ArcLight, Barclays, K&E and members of management of the Partnership. Mr. Boutin

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made a presentation to the Conflicts Committee with respect to the business of the Partnership, including the Partnership's recent performance, management's financial projections for the Partnership and potential growth opportunities for the Partnership.

        On July 12, 2018, the Conflicts Committee held a telephonic meeting with representatives of RLF and representatives of a Unitholder that is not affiliated with a Sponsor Entity. The representatives of such Unitholder presented their views on the July 9th Offer to the Conflicts Committee. Following the July 12, 2018 meeting, at the request of certain Unitholders that are not affiliated with the Sponsor Entities, the Conflicts Committee and its advisors held similar meetings on July 31, 2018, August 10, 2018, August 20, 2018 and November 15, 2018 at which such Unitholders presented their views on the July 9th Offer to the Conflicts Committee.

        On July 12, 2018, RLF circulated to each member of the Conflicts Committee a questionnaire to ascertain whether such member met the qualifications for membership on the Conflicts Committee set forth in the Partnership Agreement or had any relationship that would interfere with the exercise of his independent judgment in carrying out the responsibilities of, or that would be likely to have an adverse impact on his ability to fulfill his obligations as a member of, the Conflicts Committee in evaluating the Merger. It was subsequently determined that each member met the qualifications for membership on the Conflicts Committee and could fulfill his obligations on the committee.

        Between July 13, 2018 and July 16, 2018, the Sponsor Entities had several discussions with members of Partnership management regarding the initial diligence questions the Sponsor Entities received from the Conflicts Committee and its advisors regarding the July 9th Offer.

        On July 14, 2018, the Conflicts Committee held a telephonic meeting with representatives of RLF to discuss Evercore's proposed fee and engagement letter in connection with its work as financial advisor to the Conflicts Committee.

        On July 19, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. During the meeting, representatives of Evercore presented a preliminary analysis to the Conflicts Committee of the financial terms of the Merger based on the financial projections received from management of the Partnership. On July 23, 2018, an affiliate of ArcLight engaged Barclays as its financial advisor in connection with the Merger.

        On July 26, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. During the meeting, representatives of Evercore presented the Conflicts Committee with a preliminary analysis of the financial terms of the Merger.

        On July 27, 2018, the GP Board adopted resolutions authorizing the Conflicts Committee to (i) review and evaluate the terms and conditions of, and to determine the advisability of, the Merger on behalf of the Partnership and the Unaffiliated Unitholders, (ii) negotiate with the Sponsor Entities with respect to the terms and conditions of the Merger, (iii) determine whether or not to approve the Merger by Special Approval, and (iv) make any recommendations to the GP Board regarding the Merger as the Conflicts Committee shall determine to be appropriate.

        On July 29, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. During the meeting, Evercore reported on its diligence with Partnership management regarding the financial projections for the Partnership and certain related sensitivity cases, and representatives of Evercore presented the Conflicts Committee with a preliminary analysis of the financial terms of the Merger. The Conflicts Committee discussed Evercore's preliminary analysis, viewpoints expressed by certain Unitholders to the Committee, the outlook for the Partnership as a standalone MLP, and potential counterproposals to the July 9th Offer. The Conflicts Committee directed Evercore to send its preliminary estimated tax analysis of the effects of the Merger on the Unitholders to Barclays and to discuss the preliminary estimated tax analysis with Barclays. It was determined that, subject to Evercore's discussion with Barclays, the Conflicts Committee would propose

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to the Sponsor Entities that (i) each Common Unit held by Unaffiliated Unitholders be exchanged for $46.00 in cash and (ii) the Merger be conditioned upon receipt of approval by a majority of the Common Units held by Unaffiliated Unitholders (the "Majority of the Unaffiliated Vote Condition").

        On July 29, 2018, at the direction of the Conflicts Committee, Evercore delivered its preliminary estimated tax analysis of the effects of the Merger to Barclays and discussed its analysis with Barclays. Following such discussion, on July 31, 2018, the Conflicts Committee authorized Evercore to deliver the counterproposal discussed at its July 29 ^th  meeting to Barclays.

        On August 1, 2018, Evercore, at the direction of the Conflicts Committee, verbally communicated the counterproposal discussed at the Conflicts Committee's meeting on July 29, 2018 to Barclays. Barclays subsequently relayed the proposal to the Sponsor Entities.

        On August 7, 2018, Barclays verbally communicated a revised offer of $39.50 per Common Unit held by Unaffiliated Unitholders to Evercore and delivered to Evercore a slide showing illustrative multiples calculations using different valuation methodologies. Evercore subsequently provided the slide to the Conflicts Committee.

        Also on August 7, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. Evercore reported the revised offer delivered by Barclays to Evercore earlier that day and explained Barclays' illustrative multiple calculations. Representatives of Evercore also presented the Conflicts Committee with a preliminary analysis of the revised offer. It was noted that the Sponsor Entities had not responded to the Conflicts Committee's proposed Majority of the Unaffiliated Vote Condition. The Conflicts Committee did not make any determination regarding the Sponsor Entities' counterproposal at this meeting.

        On August 13, 2018, the Conflicts Committee held a telephonic meeting with representatives of RLF and Evercore. During the meeting, representatives of Evercore presented the Conflicts Committee with a preliminary analysis of the revised offer. The Conflicts Committee and its advisors discussed potential counterproposals to the Sponsor Entities' most recent proposal and the supporting arguments for such counterproposals. Following discussion, the Conflicts Committee determined to make a counterproposal consisting of (i) $44.00 in cash for each Common Unit held by Unaffiliated Unitholders and (ii) the Majority of the Unaffiliated Vote Condition. The Conflicts Committee directed Evercore to deliver the counterproposal to Barclays on behalf of the Conflicts Committee.

        Later on August 13, 2018, at the direction of the Conflicts Committee, Evercore verbally communicated the Conflicts Committee's revised offer to Barclays. Barclays subsequently relayed the proposal to the Sponsor Entities.

        On September 28, 2018, Barclays verbally communicated a revised offer of $40.25 per Common Unit held by Unaffiliated Unitholders to Evercore. Evercore subsequently relayed the proposal to the Conflicts Committee.

        On October 3, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. Evercore reported the most recent offer made by the Sponsor Entities and noted that the Sponsor Entities had not responded to the Majority of the Unaffiliated Vote Condition. Evercore provided an update regarding its diligence of the Partnership's financial projections and presented the Conflicts Committee with a preliminary analysis of the revised offer. The Conflicts Committee discussed potential counterproposals to the Sponsor Entities' most recent offer. Following discussion, the Conflicts Committee determined to make a counterproposal consisting of (i) $42.50 for each Common Unit held by Unaffiliated Unitholders and (ii) the Majority of the Unaffiliated Vote Condition and directed Evercore to deliver the counterproposal to Barclays on behalf of the Conflicts Committee.

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        Later on October 3, 2018, at the direction of the Conflicts Committee, Evercore verbally communicated the Conflicts Committee's revised offer to Barclays. Barclays subsequently relayed the proposal to the Sponsor Entities.

        On October 11, 2018, Barclays, at the direction of the Sponsor Entities, verbally communicated a "best and final" counteroffer to Evercore of (i) $41.00 for each Common Unit held by Unaffiliated Unitholders and (ii) rejected the Majority of the Unaffiliated Vote Condition.

        On October 12, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. Evercore reported the most recent offer made by the Sponsor Entities and noted that Barclays had stated that such offer was the Sponsor Entities' best and final offer. Representatives of Evercore presented the Conflicts Committee with a preliminary analysis of the revised offer. There was discussion regarding the merits of the Merger and the outlook for the Partnership if the Merger were rejected and the Partnership remained a publicly traded partnership.

        On October 14, 2018, the Conflicts Committee held a telephonic meeting with representatives of RLF and Evercore and members of management of the Partnership. The Conflicts Committee described the Sponsor Entities' best and final offer and asked management questions regarding its financial projections, the outlook for the Partnership if the Partnership remained a publicly traded partnership, the state of MLP capital markets and expected timing for the Partnership's distributions with respect to the third and fourth quarters of 2018.

        Following the meeting on October 14, 2018, at the direction of the Conflicts Committee, Evercore communicated to Barclays that, subject to negotiation of definitive documentation, the Conflicts Committee was prepared to accept the offer of $41.00 for each Common Unit held by Unaffiliated Unitholders, but also requested that each unitholder receive the full quarterly distribution for any completed quarter if Closing occurred prior to the record date for the immediately preceding quarter and a pro-rata distribution for the quarter during which Closing occurs. Barclays conveyed the request to the Sponsor Entities. After further discussion with the Sponsor Entities and Kirkland, Barclays, on behalf of the Sponsor Entities, communicated to Evercore that the distribution point remained open, but the parties could proceed to negotiation of definitive documentation.

        On October 17, 2018, Kirkland separately discussed the process for preparation of the Merger Agreement with Latham & Watkins LLP ("Latham") and RLF.

        On October 23, 2018, Kirkland delivered an initial draft of the Merger Agreement to Latham and RLF. The initial draft of the Merger Agreement provided, among other things, that (i) the Partnership could not solicit any proposal that could constitute an acquisition proposal (a "no-shop" provision), (ii) the Conflicts Committee could only change its recommendation with respect to the Merger if it determined in good faith (after consultation with its financial advisor and outside legal counsel) that an acquisition proposal constitutes a superior proposal and that the failure to take such action would constitute a breach of its duties under the Partnership Agreement and applicable law, and (iii) acknowledged that TLP Holdings would obtain debt and equity financing to fund the merger consideration and, if the Merger Agreement was terminated under certain circumstances, TLP Holdings' liability would be capped at a reverse termination fee equal to 4% of the merger consideration. The initial draft of the Merger Agreement did not contemplate delivery of the Support Agreement or the payment of the quarterly distribution for any completed quarter if the Closing occurred prior to the record date for the immediately preceding quarter.

        On October 29, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. RLF provided an overview of the terms of the initial draft of the Merger Agreement. The Conflicts Committee provided feedback to RLF and directed RLF to work with Latham to prepare revisions to the Merger Agreement and send the revisions to Kirkland.

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        On November 1, 2018, Latham delivered a revised draft of the Merger Agreement to Kirkland reflecting the revisions the Conflicts Committee discussed with RLF, including, among others, (i) providing for less restrictive circumstances under which the GP Board and/or the Conflicts Committee could change their recommendations regarding the Merger, (ii) requiring a support agreement from TLP Holdings and Equity Holdings, (iii) deleting the operational representations related to the Partnership, including representations made by the Partnership concerning absence of changes, tax matters, employee benefits and labor matters, title to properties, material contracts, compliance with laws, environmental matters, insurance and regulatory matters, (iv) providing for the merger consideration to be increased at Closing by (x) a daily distribution amount for the number of days from the end of the prior quarter to Closing and (y) the quarterly distribution for any completed quarter if Closing occurred prior to the record date for the immediately preceding quarter, and (v) removing all provisions relating to equity and debt financing and the reverse termination fee that capped TLP Holdings' liability if the Merger Agreement was terminated.

        After discussion with the Sponsor Entities, on November 12, 2018, Kirkland delivered a revised draft of the Merger Agreement to Latham and RLF. The draft (i) accepted the Conflicts Committee's proposed deletion of the operational representations, (ii) provided for the merger consideration to be increased at Closing by the quarterly distribution for any completed quarter if the record date for the prior quarter had not yet occurred, (iii) rejected the proposed payment of a daily distribution amount for the number of days from the end of the prior quarter to Closing, and (iv) allowed the Conflicts Committee to withdraw or change its recommendation regarding the Merger Agreement if it determines in good faith (after consultation with its financial advisors and outside legal counsel) that the failure to take such action would constitute a breach of, or be otherwise inconsistent with, the Conflicts Committee's duties under the Partnership Agreement or applicable law, subject to a customary notice and negotiation period in favor of TLP Holdings. The draft included the proposed debt and equity financing provisions and the reverse termination fee that capped TLP Holdings' liability at 4% of the merger consideration if the Merger Agreement was terminated under certain circumstances.

        On November 13, 2018, Latham delivered an initial draft of the disclosure schedules to the Merger Agreement to Kirkland.

        On November 15, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. RLF presented the terms of Kirkland's most recent draft of the Merger Agreement. The Conflicts Committee discussed the terms of the draft and directed RLF to work with Latham to prepare revisions to the Merger Agreement consistent with the Conflicts Committee's feedback and instruction, which included the following proposals: (i) the merger consideration include a daily distribution amount for the number of days from the end of the prior quarter to Closing, (ii) a reverse termination fee of 6% of the merger consideration and a fund guarantee from an affiliate of ArcLight guaranteeing payment of the reverse termination fee (the "Limited Guarantee") and (iii) strengthening certain representations, warranties and covenants related to the financing of the Merger Consideration.

        On November 16, 2018, Latham delivered a revised draft of the Merger Agreement to Kirkland. The November 16, 2018 draft generally accepted the changes proposed by the Sponsor Entities in the November 12, 2018 draft, with the exception that the revised draft included the Conflicts Committee's proposals discussed at the Conflicts Committee's meeting on November 15, 2018.

        On November 19, 2018, Kirkland delivered revised drafts of the Merger Agreement and disclosure schedules to Latham and RLF. The revised draft Merger Agreement removed the daily distribution amount and decreased the reverse termination fee to 5% of the merger consideration, but accepted the modifications to representations, warranties and covenants relating to the financing of the Merger Consideration, as well as the Limited Guarantee.

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        Also on November 19, 2018, Latham delivered an initial draft of the Support Agreement to Kirkland.

        On November 20, 2018, Kirkland delivered initial drafts of the Equity Commitment Letter and the Limited Guarantee to Latham and RLF. Also on such date, ArcLight's affiliate assigned and novated to Parent its engagement letter with Barclays and all of ArcLight's rights, interest, benefits, liabilities, responsibilities and obligations under, in and to such letter.

        On November 20, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. RLF explained to the Conflicts Committee that the Sponsor Entities had rejected the daily distribution proposal and proposed a 5% reverse termination fee. The Conflicts Committee discussed the terms of the Merger Agreement and directed RLF to contact Kirkland and provide a counterproposal on the Conflicts Committee's behalf consisting of (i) a daily distribution amount that accrues on a month-end basis from the end of the prior quarter to Closing and (ii) a 6% reverse termination fee. Following the Conflicts Committee meeting, RLF contacted Kirkland and delivered such counterproposal.

        After discussion, the Sponsor Entities instructed Kirkland to reject both points of the Conflicts Committee's counterproposal, and Kirkland conveyed the message to Latham and RLF.

        Also on November 20, 2018, the ArcLight Capital Holdings, LLC investment committee approved of the relevant Sponsor Entities' entry into the Merger Agreement, the Equity Commitment Letter and Limited Guarantee, subject to final negotiation of the relevant documents.

        On November 21, 2018, Latham delivered revised drafts of the Equity Commitment Letter and Limited Guarantee to Kirkland, and Kirkland delivered the execution version of the Financing Documents to Latham.

        On November 23, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF. RLF reported that the Sponsor Entities had rejected each of the Conflicts Committee's counterproposals discussed at the meeting on November 20, 2018. RLF also provided an update on the ancillary documents to the Merger Agreement, including the Financing Documents and the Limited Guarantee. There was discussion regarding Evercore's preliminary financial analysis of the Merger, the Sponsor Entities' current offer, the spot price of Common Units, and the trading performance of the Alerian index since the time of the July 9th Offer. After discussion, the Conflicts Committee determined that, subject to the satisfactory negotiation of the Merger Agreement and the related documents and the receipt of an opinion of Evercore as to the fairness of the Merger to the holders of Common Units other than TLP Holdings, Parent, Merger Sub, the General Partner and their respective affiliates, it would be in the best interests of the Partnership and the Unaffiliated Unitholders to accept the Sponsor Entities' current offer.

        After such meeting, RLF informed Latham, and Latham subsequently informed Kirkland, that the Conflicts Committee had accepted the Sponsor Entities' proposal on the two remaining commercial points, specifically eliminating the payment of any distributions for the quarter in which the Closing occurs and accepting the reverse termination fee equal to 5% of the merger consideration.

        During the afternoon of November 23, 2018, Latham delivered a revised draft of the Merger Agreement to Kirkland incorporating minor changes.

        In the afternoon on November 25, 2018, Kirkland provided substantially final drafts of the Merger Agreement, Financing Documents, Limited Guarantee and Support Agreement to Latham and RLF.

        On the evening of November 25, 2018, the Conflicts Committee held a telephonic meeting with representatives of Evercore and RLF to discuss the Merger, including the terms and conditions of the Merger Agreement and the other transaction documents. During the meeting, RLF presented to the Conflicts Committee an overview and update with respect to the terms of the Merger Agreement and

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the related documents. Also at this meeting, representatives of Evercore presented its financial analysis of the Merger Consideration and, at the request of the Conflicts Committee, rendered an oral opinion to the Conflicts Committee, which was subsequently confirmed by delivery of a written opinion dated November 25, 2018, to the effect that, as of the date of its opinion, and based upon the assumptions made, matters considered, procedures followed, and qualifications and limitations of the review undertaken in rendering its opinion as set forth therein, the Merger Consideration was fair, from a financial point of view, to the Unaffiliated Unitholders. At this meeting, the Conflicts Committee (i) determined that the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders, (ii) approved the Merger Agreement and the transactions contemplated thereby, including the Merger, which action constituted "Special Approval" as defined in the Partnership Agreement, (iii) recommended that the GP Board approve the Merger Agreement, the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended that the GP Board submit the Merger Agreement to a vote of the Unitholders and recommend approval of the Merger Agreement by the Unitholders, and (v) recommended that the Unitholders approve the Merger Agreement.

        Later in the evening on November 25, 2018, at a telephonic meeting of the GP Board, the GP Board (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders, (ii) approved the Merger Agreement, the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iii) resolved to submit the Merger Agreement to a vote of the Unitholders and (iv) recommended approval of the Merger Agreement, including the Merger, by the Unitholders.

        Later in the evening of November 25, 2018, the parties executed the Merger Agreement, Financing Documents, Limited Guarantee and Support Agreement.

        On the morning of November 26, 2018, the Sponsor Entities and the Partnership issued press releases announcing the Merger Agreement.

Resolution of Conflicts of Interest; Standards of Conduct and Modification of Duties

        Under Section 7.9(a) of the Partnership Agreement, whenever a potential conflict of interest exists or arises between the General Partner or any of its affiliates, on the one hand, and the Partnership or any partner of the Partnership, on the other, such as the consideration of the Merger Agreement and the transactions contemplated thereby, any resolution or course of action by the General Partner or its affiliates in respect of such conflict of interest is permitted and deemed approved by all partners of the Partnership, and does not constitute a breach of the Partnership Agreement, any organizational document of the Partnership's subsidiaries, any agreement contemplated by the Partnership Agreement or any duty stated or implied by law or equity, if the resolution or course of action in respect of such conflict of interest is approved by Special Approval. For purposes of the Partnership Agreement, Special Approval means approval by a majority of the members of the Conflicts Committee.

        Under Section 7.9(b) of the Partnership Agreement, whenever the General Partner makes a determination or takes or declines to take any other action, or any of its affiliates causes it do so, in its capacity as the general partner of the Partnership as opposed to in its individual capacity, whether under the Partnership Agreement, any organizational document of the Partnership's subsidiaries or any other agreement contemplated by the Partnership Agreement, then, unless another express standard is provided for in the Partnership Agreement, the General Partner, or such affiliate causing it do so, shall make such determination or decline to take such other action in good faith and shall not be subject to any other or different standards imposed by the Partnership Agreement, any organizational document of the Partnership's subsidiaries, any other agreement contemplated by the Partnership Agreement or under applicable law.

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        Pursuant to Section 7.9(b) of the Partnership Agreement, in order for a determination or other action to be in "good faith," the person or persons making such determination or taking or declining to take such other action must believe that the determination or other action is in the best interests of the Partnership.

        Under Section 7.10(b) of the Partnership Agreement, the General Partner may consult with legal counsel, accountants, appraiser, management consultants, investment bankers and other consultants and advisors selected by it, and act any taken or omitted to be taken in reliance upon the opinion of such of such persons as to matters that the General Partner reasonably believes to be within such person's professional or expert competence is conclusively presumed to have been done or omitted in good faith and in accordance with such opinion.

Recommendation of the Conflicts Committee and the GP Board; Reasons for Recommending Approval of the Merger Proposal

The Conflicts Committee

        The Conflicts Committee consists of three directors that meet the independence qualifications for membership on a conflicts committee set forth in the Partnership Agreement: Barry Welch (Chairman), Steven Blank and Jay Wiese. The GP Board, on July 27, 2018, resolved by unanimous written consent to delegate to the Conflicts Committee the power and authority (i) to review and evaluate the terms and conditions of, and to determine the advisability of, the Merger on behalf of the Partnership and the Unaffiliated Unitholders, (ii) to negotiate, or delegate to any person or persons the ability to negotiate, with TLP Holdings and its affiliates and their representatives, or any other appropriate person, with respect to the terms and conditions of the Merger, (iii) to determine whether or not to approve the Merger by "Special Approval" (pursuant to Section 7.9(a) of the Partnership Agreement), and (iv) to make any recommendations to the GP Board regarding the Merger as the Conflicts Committee shall determine to be appropriate.

        The Conflicts Committee retained Evercore as its financial advisor and RLF as its legal counsel. The Conflicts Committee conducted a review and evaluation of the Merger and the Merger Agreement and negotiated with TLP Holdings and its representatives with respect to the Merger and the Merger Agreement.

        On November 25, 2018, the Conflicts Committee unanimously (i) determined that the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders, (ii) approved the Merger Agreement and the transactions contemplated thereby, including the Merger, which action constituted "Special Approval" as defined in the Partnership Agreement, (iii) recommended that the GP Board approve the Merger Agreement, the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended that the GP Board submit the Merger Agreement to a vote of the Unitholders and recommend approval of the Merger Agreement by the Unitholders and (v) recommended that the Unitholders approve the Merger Agreement.

Reasons for the Conflicts Committee's Recommendation

        The Conflicts Committee consulted with its financial and legal advisors and considered many factors in making its determination and approvals, and the related recommendation to the GP Board and the Unitholders. The Conflicts Committee considered the following factors to be generally positive

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or favorable in making its determination and approvals, and the related recommendation to the GP Board and the Unitholders:

•

The Merger Consideration is an all-cash amount, which the Conflicts Committee believes provides greater value to the Unaffiliated Unitholders than the long-term value of the Partnership as a publicly traded partnership, after taking into account the risks and challenges facing the Partnership's current business and financial prospects.



•

The Merger Consideration constitutes a 12.6% premium to the price per Common Unit on November 23, 2018 (the last trading day prior to the approval of the Merger) and a 13.5% premium to the price per Common Unit on July 9, 2018 (the last trading day prior to the time that TLP Holdings offered to acquire all of the Common Units held by Unaffiliated Unitholders).



•

The Merger Consideration constitutes a 7.9% premium to TLP Holding's initial offer of $38.00 per Common Unit made on July 9, 2018, and, from July 9, 2018 to November 23, 2018, the Alerian MLP Index has decreased by 8.5%.



•

The Conflicts Committee's belief that $41.00 was the highest price per Common Unit that TLP Holdings would be willing to pay to the Unaffiliated Unitholders in connection with the Merger.



•

The Conflicts Committee's belief that the state of the MLP equity capital markets will continue to make it difficult for the Partnership to fund acquisitions and growth capital expenditures.



•

The Merger Consideration provides liquidity to the Unaffiliated Unitholders.



•

The financial analysis prepared by Evercore, as financial advisor to the Conflicts Committee, and the oral opinion of Evercore delivered to the Conflicts Committee on November 25, 2018, which was subsequently confirmed by delivery of a written opinion of Evercore, dated November 25, 2018, to the effect that, as of such date, and based upon the assumptions made, matters considered, procedures followed, and qualifications and limitations of the review undertaken in rendering its opinion as set forth therein, the Merger Consideration was fair, from a financial point of view, to the Unaffiliated Unitholders.



•

The Merger is subject to receipt of Unitholder Approval; recognizing that affiliates of ArcLight hold approximately 19.5% of the Common Units as of November 23, 2018 (with TLP Holdings owning approximately 4.9% of the Common Units and Equity Holdings owning approximately 14.6% of the Common Units as of November 23, 2018).



•

The Partnership, TLP Holdings, and Equity Holdings have entered into a Support Agreement, included as Annex C to this proxy statement, pursuant to which each of TLP Holdings and Equity Holdings have agreed to vote all of its Common Units in favor of adoption of the Merger Agreement and any other matter necessary or desirable for the consummation of the transactions contemplated by the Merger Agreement, including the Merger.



•

ArcLight, pursuant to an equity commitment letter delivered by ArcLight to Parent, has committed to purchase equity of Parent for an aggregate cash purchase price up to $33,708,000 solely for the purpose of providing cash to Parent to fund the Merger Consideration.



•

The Merger Consideration is intended to be partially funded by a $525,000,000 senior secured credit facility among Parent, TLP Holdings and the lenders named therein entered into concurrently with the execution of the Merger Agreement (the "Debt Financing").



•

The financial terms and conditions of the Merger and the non-financial terms and conditions of the Merger Agreement were determined as a result of arm's-length negotiations between TLP Holdings and the Conflicts Committee and their respective representatives and advisors that included multiple proposals and counterproposals.

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•

Certain terms of the Merger Agreement, principally:



•

Provisions requiring the General Partner to declare and cause the Partnership to pay regular quarterly cash distributions of $0.805 per Common Unit until closing with the payment date for each quarterly distribution to be no later than 45 days after the end of each fiscal quarter.



•

Provisions requiring Parent to pay to the Partnership the Termination Fee in the event the Merger Agreement is terminated under certain circumstances. See " Proposal No. 1. The Merger Agreement—Remedies, Specific Performance ."



•

Provisions requiring Parent to take all actions and to do all things necessary, proper or advisable to consummate and obtain the Debt Financing at closing.



•

Provisions requiring Parent to use commercially reasonable efforts to arrange, consummate and obtain alternative debt financing from the same or alternative financial institutions if any portion of the Debt Financing becomes unavailable upon terms and conditions no less favorable, in the aggregate, to Parent or the Partnership (as determined in the reasonable judgment of Parent).



•

Provisions permitting the Partnership and the General Partner, under certain conditions, to negotiate with respect to certain unsolicited acquisition proposals.



•

Provisions permitting the Conflicts Committee to change its recommendation to the Unitholders if the Conflicts Committee determines in good faith (after consultation with its financial advisor and outside legal counsel) that a failure to make a recommendation change would constitute a breach of, or be otherwise inconsistent with, the Conflicts Committee's duties under the Partnership Agreement or applicable law.



•

Provisions restricting the removal of the members of the Conflicts Committee between signing of the Merger Agreement and closing of the Merger.



•

Provisions requiring the consent of the Conflicts Committee to amendments to the Merger Agreement.



•

The Limited Guarantee made by Pike Petroleum Holdings, LLC in favor of the Partnership guaranteeing the timely payment of the Termination Fee (if payable).



•

The Conflicts Committee's engagement of financial and legal advisors with knowledge and experience with respect to public merger and acquisition transactions, MLPs, the Partnership's industry generally, and the Partnership particularly, as well as substantial experience advising MLPs and other companies with respect to transactions similar to the Merger.

        The Conflicts Committee considered the following factors to be generally negative or unfavorable in making its determination and approvals, and the related recommendation to the GP Board and the Unitholders:

•

The Conflicts Committee was not authorized to and did not conduct an auction process or other solicitation of interest from third parties for the acquisition of the Partnership. Since TLP Holdings indirectly controls the Partnership, it was unrealistic to expect an unsolicited third-party acquisition proposal to acquire assets or control of the Partnership, and it was unlikely that the Conflicts Committee could conduct a meaningful process to solicit interest in the acquisition of assets or control of the Partnership.



•

The Merger is expected to be taxable to the Unaffiliated Unitholders.



•

The Unaffiliated Unitholders will not have any equity participation in the Partnership following the Merger, and the Unaffiliated Unitholders will accordingly cease to participate in the

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Partnership's future earnings or growth, if any, or benefit from any increases, if any, in the value of the Common Units.

•

The Unaffiliated Unitholders are not entitled to dissenters' or appraisal rights under the Merger Agreement, the Partnership Agreement or Delaware law.



•

Unaffiliated Unitholders will not receive a pro rata share of the Partnership's distribution for the fiscal quarter during which closing occurs.



•

Certain terms of the Merger Agreement, principally:



•

Provisions requiring the Partnership to reimburse Parent for out-of-pocket expenses up to $5,000,000 in the event the Merger Agreement is terminated under certain circumstances.



•

Provisions requiring the Partnership to submit the Merger Agreement to a vote of the Unitholders (even if the Conflicts Committee has made a recommendation change), unless the Merger Agreement has been validly terminated.



•

Provisions limiting the Partnership's available remedies to the Termination Fee in the event the Merger Agreement is terminated under certain circumstances.



•

The Partnership has incurred and will continue to incur transaction costs and expenses in connection with the Merger, whether or not the Merger is completed.



•

TLP Holdings, Equity Holdings, ArcLight and some of the executive officers and directors of the General Partner have interests in the Merger that are different from, or in addition to, the interests of the Unaffiliated Unitholders generally.

        The foregoing discussion of the information and factors considered by the Conflicts Committee is not intended to be exhaustive, but includes material factors the committee considered. In view of the variety of factors considered in connection with its evaluation of the Merger and the complexity of these matters, the Conflicts Committee did not find it useful and did not attempt to quantify or assign any relative or specific weights to the various factors considered in making its determination and recommendation. In addition, each of the members of the Conflicts Committee may have given differing weights to different factors. Overall, the Conflicts Committee believed that the positive factors supporting the Merger outweighed the negative factors it considered. It should be noted that certain statements and other information presented in this section are forward-looking in nature and, therefore, should be read in light of the factors discussed under the heading "Cautionary Statement Regarding Forward-Looking Statements."

         The Conflicts Committee recommends that the Unitholders vote "FOR" the approval of the Merger Proposal.

The GP Board

        The GP Board consists of seven directors, three of whom are independent (Steven Blank, Barry Welch and Jay Wiese). As such, some of the directors on the GP Board may have different interests in the Merger than the Unaffiliated Unitholders. For a complete discussion of these and other interest of the members of the GP Board in the Merger, see " —Interests of the Directors and Executive Officers of the General Partner in the Merger ." Because of such possible and actual conflicts of interests, in resolutions approved by the GP Board on July 27, 2018, the GP Board delegated to the Conflicts Committee the full power and authority of the GP Board to (i) review and evaluate the terms and conditions of, and to determine the advisability of, the Merger on behalf of the Partnership and the Unaffiliated Unitholders, (ii) negotiate, or delegate to any person or persons the ability to negotiate, with TLP Holdings and its affiliates and their representatives, or any other appropriate person, with respect to the terms and conditions of the Merger, (iii) determine whether or not to approve the

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Merger by "Special Approval" and (iv) make any recommendations to the GP Board regarding the Merger as the Conflicts Committee shall determine to be appropriate.

        On November 25, 2018, the Conflicts Committee unanimously determined that each of the Merger Agreement and the Merger is in the best interests of the Partnership and the Unaffiliated Unitholders. Based upon such determination, the Conflicts Committee recommended to the GP Board that the GP Board approve the Merger Agreement, the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger. On November 25, 2018, the GP Board, after considering the factors discussed below, including the unanimous determination and recommendation of the Conflicts Committee, (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of the Partnership and the Unaffiliated Unitholders, (ii) approved the Merger Agreement, the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iii) resolved to submit the Merger Agreement to a vote of the Unitholders and (iv) recommended approval of the Merger Agreement, including the Merger, by the Unitholders. The GP Board recommends that the Unitholders vote in favor of the Merger Proposal.

        In determining that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interest of the Partnership and the Unaffiliated Unitholders, and recommending that Unitholders vote in favor of the Merger Proposal, the GP Board considered a number of factors, including the following material factors:

•

the unanimous determination and recommendation of the Conflicts Committee; and



•

the factors considered by the Conflicts Committee, including the material factors considered by the Conflicts Committee described under " —The Conflicts Committee " above.

        In doing so, the GP Board expressly adopted the analysis of the Conflicts Committee, which is discussed above. In addition, under the SEC rules governing "going private" transactions, the Partnership and the General Partner are engaged in a "going private" transaction and, therefore, are required to express their position as to the fairness of the proposed Merger to the Partnership's "unaffiliated security holders," as defined under Rule 13e-3 of the Exchange Act. The GP Board, on behalf of the General Partner and the Partnership, and the Conflicts Committee are making the following statements solely for the purpose of complying with the requirements of Rule 13e-3 and related rules under the Exchange Act. The GP Board, on behalf of the General Partner and the Partnership, on the basis of the factors described above, believes that the Merger (which is the Rule 13e-3 transaction for which a Schedule 13E-3 Transaction Statement was filed with the SEC) is both procedurally and substantively fair to the Unaffiliated Unitholders.

        The foregoing discussion is not intended to be exhaustive, but is intended to address the material information and principal factors considered by the GP Board in considering the Merger. In view of the various factors and information considered, the GP Board did not find it practicable to, and did not make specific assessments of, quantify or otherwise assign relative weights to, the specific factors considered in reaching its determination. In addition, the GP Board did not undertake to make any specific determination as to whether any particular factor, or any aspect of any particular factor, was determinative of its ultimate determination, and individual members of the GP Board may have given different weights to different factors. The GP Board made its recommendation based on the totality of information presented to, and the investigation conducted by, the GP Board. It should be noted that certain statements and other information presented in this section are forward-looking in nature and, therefore, should be read in light of the factors discussed under the heading "Cautionary Statement Regarding Forward-Looking Statements."

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         The GP Board recommends that the Unitholders vote "FOR" the approval of the Merger Proposal and "FOR" the adjournment of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the Merger Proposal at the time of the Special Meeting.

Unaudited Financial Projections of the Partnership

        The Partnership does not, as a matter of course, publicly disclose long-term financial projections because of, among other reasons, the uncertainty of the underlying assumptions and estimates and the unpredictability of its business and competitive markets in which it operates. While the Partnership prepares forecasts annually for internal budgeting and business planning purposes, such forecasts generally focus on the current fiscal year and the immediately following three fiscal years.

        The summary financial projections included in this proxy statement should not be regarded as predictive of actual future results nor should they be construed as financial guidance. The summary of the financial projections is not intended to influence or induce any Unitholder to vote in favor of the Merger Proposal but has been included solely because these financial projections were made available to the Conflicts Committee and used by Evercore in connection with the rendering of its fairness opinion to the Conflicts Committee and performing its related financial analyses, as described in the section entitled " Special Factors—Opinion of Financial Advisor to the Conflicts Committee ."

        The financial projections included in this proxy statement are not the only series of projections that were prepared in connection with the Merger given the extended negotiation period. At the beginning of the negotiation process, the Conflicts Committee and Evercore each received an initial series of financial projections. The Partnership continued to update these financial projections over the course of negotiations prior to execution of the Merger Agreement as new business facts evolved. As these new business facts evolved, the Partnership informed the Conflicts Committee of such facts.

        The Partnership's financial projections are subjective in many respects. There can be no assurance that these financial projections will be realized or that actual results will not be significantly higher or lower than forecasted. In addition, the financial projections were not prepared with a view toward public disclosure or toward complying with generally accepted accounting principles in the United States ("GAAP"), the published guidelines of the SEC regarding projections or the use of non-GAAP financial measures 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 proxy statement has been prepared by, and is the responsibility of, Partnership's management. Deloitte & Touche LLP has neither audited, reviewed, examined, compiled nor applied agreed-upon procedures with respect to the accompanying prospective financial information and, accordingly, Deloitte & Touche LLP does not express an opinion or any other form of assurance with respect thereto. The Deloitte & Touche LLP report incorporated by reference in this proxy statement relates to the Partnership's historical financial information. It does not extend to the prospective financial information and should not be read to do so.

        In developing the financial projections for the years 2018 through 2021, the Partnership made numerous material assumptions with respect to its business for the periods covered by the projections. The Partnership developed a management case (the "Management Case") of financial projections, and the Management Case assumptions included, but were not limited to, the following:

•

the timing, construction and start-up of growth projects of the Partnership, as well as the annual cash return and spending of the Partnership associated with such projects;



•

the amount and timing of distributions to the Unitholders by the Partnership;



•

the amounts and nature of future capital expenditures, including the allocation of capital to maintenance and growth capital expenditures;

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•

the sources of funding for future growth projects, including pursuant to the Partnership's at-the-market offering program or access to other debt or equity markets;



•

the amount and timing of the administrative fee paid by the Partnership under its Omnibus Agreement;



•

the amounts of revenue and expenses per budget;



•

the ability of the Partnership to remain a public entity; and



•

other general business, market, industry, commodity pricing and interest rate assumptions.

        Important factors that may affect actual results and cause these financial projections not to be achieved include, but are not limited to, risks and uncertainties relating to the Partnership's business (including the Partnership's ability to achieve strategic goals, objectives and targets over the applicable periods), industry performance, general business and economic conditions, the regulatory environment and other factors described in or referenced under " Cautionary Statement Regarding Forward-Looking Statements " and those risks and uncertainties detailed in the Partnership's public filings with the SEC. In addition, the projections also reflect assumptions that are subject to change and do not reflect revised prospects for the Partnership's business, changes in general business or economic conditions or any other transaction or event that has occurred or that may occur following the time the financial projections were prepared. Accordingly, there can be no assurance that these financial projections will be realized or that the Partnership's future financial results will not materially vary from these financial projections. In addition, different assumptions could result in different projections, which may or may not be realized. No one has made or makes any representation to any Unitholder regarding the information included in the financial projections set forth below. The Partnership has made no representation to the Arclight Filing Entities in the Merger Agreement concerning these or any financial projections.