SUN Sunoco LP

As filed with the Securities and Exchange Commission on February 26, 2024

Registration No. 333-     

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

SUNOCO LP

(Exact name of registrant as specified in its charter)

8111 Westchester Drive, Suite 400

Dallas, TX 75225

(214) 981-0700

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Scott D. Grischow

Arnold D. Dodderer

Sunoco GP LLC

8111 Westchester Drive

Suite 400

Dallas, TX 75225

(214) 981-0700

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after the effectiveness of this registration statement and the satisfaction or waiver of all other conditions to the closing of the merger described herein.

If the securities being registered on this form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. ☐

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ☐

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this document is not complete and may be changed. Sunoco LP may not issue the securities described herein until the registration statement filed with the Securities and Exchange Commission is effective. This document is not an offer to sell these securities and is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED FEBRUARY 26, 2024

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

Dear NuStar Energy L.P. Common Unitholders:

On January 22, 2024, NuStar Energy L.P., a Delaware limited partnership (“NuStar”), entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Sunoco LP, a Delaware limited partnership (“Sunoco”), Saturn Merger Sub, LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Sunoco (“Merger Sub”), Riverwalk Logistics, L.P., a Delaware limited partnership and sole general partner of NuStar (“NuStar GP”), NuStar GP, LLC, a Delaware limited liability company and the sole general partner of NuStar GP (the “NuStar Managing GP”), and Sunoco GP LLC, a Delaware limited liability company and sole general partner of Sunoco (the “Sunoco GP”), pursuant to which Sunoco will acquire NuStar in an all-equity transaction by means of a merger of Merger Sub with and into NuStar (the “Merger”) with NuStar surviving the Merger as a subsidiary of Sunoco.

Each common unit of NuStar (“NuStar Common Unit”) issued and outstanding immediately prior to the effective time of the Merger (the “Effective Time”) (other than any NuStar Common Units owned at that time by NuStar, Sunoco, Merger Sub or a Sunoco subsidiary) will be converted into and represent the right to receive 0.400 of a common unit (the “Exchange Ratio”) of Sunoco (the “Sunoco Common Units”) and, if applicable, cash in lieu of fractional units, with each person or entity so receiving Sunoco Common Units upon the exchange being admitted as a limited partner of Sunoco. In addition, prior to the Effective Time, NuStar will declare and pay a special cash distribution to the holders of NuStar Common Units (the “NuStar Common Unitholders”) in the amount of $0.212 per NuStar Common Unit (the “Special Distribution”).

The Exchange Ratio is fixed and will not be adjusted to reflect price changes prior to the closing of the Merger. NuStar Common Units and Sunoco Common Units are each traded on the New York Stock Exchange (the “NYSE”) under the ticker symbols “NS” and “SUN,” respectively. Based on the closing price of Sunoco Common Units on the NYSE of $59.46 on January 19, 2024, the last trading day before public announcement of the proposed Merger, the Exchange Ratio and Special Distribution, combined, represented approximately $24.00 in value for each NuStar Common Unit, which represented a premium of approximately 33.1% to the closing price per NuStar Common Unit on January 19, 2024. Based on the closing price of Sunoco Common Units on the NYSE of $[   ] on [    ], the latest practicable date before the date of this proxy statement/prospectus, the Exchange Ratio and Special Distribution, combined, represented approximately $[  ] in value for each NuStar Common Unit.

The value of the consideration paid to NuStar Common Unitholders will fluctuate with changes in the market price of Sunoco Common Units. We urge you to obtain current market quotations of Sunoco Common Units and NuStar Common Units.

Based upon the number of outstanding NuStar Common Units (including each NuStar Common Unit underlying each restricted unit award of NuStar) on the record date of [     ], 2024 for the NuStar Special Meeting (defined below), we anticipate that Sunoco will issue approximately [    ] Sunoco Common Units in connection with the Merger.

Upon completion of the Merger, based on the number of Sunoco Common Units and NuStar Common Units as of the date of the Merger Agreement, we estimate that legacy NuStar Common Unitholders will own approximately 38% of the Sunoco Common Units and legacy holders of Sunoco Common Units (“the Sunoco Common Unitholders”) will own approximately 62% of the Sunoco Common Units.

In connection with the Merger, NuStar will hold a virtual special meeting of the NuStar Common Unitholders (the “NuStar Special Meeting”) to consider and vote on (i) a proposal to approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Merger (the “Merger Proposal”), (ii) a proposal to approve, by a non-binding, advisory vote, the compensation that may be received by NuStar Managing GP’s named executive officers in connection with the Merger (the “Compensation Proposal”) and (iii) a proposal to approve the adjournment of the NuStar Special Meeting, if necessary, to solicit additional proxies in favor of the Merger Proposal, if (a) there are holders of an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum at such meeting or (b) there are insufficient votes at the time of such adjournment to approve the Merger Proposal (the “Adjournment Proposal”).

Your vote is very important. The record date for determining the NuStar Common Unitholders entitled to receive notice of, and to vote at, the NuStar Special Meeting is the close of business on [     ], 2024. The Merger cannot be completed without the approval of the NuStar Common Unitholders. We urge you to read this proxy statement/prospectus carefully. The obligations of Sunoco and NuStar to complete the Merger are subject to the satisfaction or waiver of certain conditions set forth in the Merger Agreement. More information about Sunoco, NuStar, the NuStar Special Meeting, the Merger Agreement and the transactions contemplated thereby, including the Merger, is included in this proxy statement/prospectus. You should also consider carefully the risks that are described in the “Risk Factors” section of this proxy statement/prospectus.

Whether or not you plan to attend the NuStar Special Meeting, please submit your proxy as soon as possible to make sure your NuStar Common Units are represented at the NuStar Special Meeting.

The board of directors of NuStar Managing GP (the “NuStar Managing GP Board”) unanimously recommends that NuStar Common Unitholders vote “FOR” the Merger Proposal, “FOR” the Compensation Proposal and “FOR” the Adjournment Proposal.

On behalf of the NuStar Managing GP Board, we thank you for your consideration and continued support. We look forward to the successful combination of Sunoco and NuStar.

Sincerely,

Bradley C. Barron

Chairman, President and Chief Executive Officer

Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be issued under the accompanying document or determined that the accompanying document is accurate or complete. Any representation to the contrary is a criminal offense.

This proxy statement/prospectus is dated [●], 2024 and is first being mailed to the NuStar Common Unitholders on or about [●], 2024.

NOTICE OF SPECIAL MEETING OF NUSTAR COMMON UNITHOLDERS

TO BE HELD VIRTUALLY ON [    ], 2024

Dear NuStar Energy L.P. Common Unitholders:

On [     ], 2024, NuStar will hold a virtual special meeting of NuStar Common Unitholders at www.virtualshareholdermeeting.com/NS2024SM, starting at [    ] Central Time (unless it is adjourned or postponed to a later date) (the “NuStar Special Meeting”). Holders of record of NuStar Common Units at the close of business on [     ], 2024 are entitled to attend and vote on the matters presented at the NuStar Special Meeting. The NuStar Special Meeting can be accessed by visiting www.virtualshareholdermeeting.com/NS2024SM, where NuStar Common Unitholders will be able to participate and vote online during the NuStar Special Meeting. To be admitted to the NuStar Special Meeting, you must enter the 16-digit control number found on your proxy card or voting instruction form.

At the NuStar Special Meeting, you will be asked to consider the following proposals:

Proposal 1: The Merger Proposal: To approve and adopt the Agreement and Plan of Merger (the “Merger Agreement”), by and among NuStar, Sunoco LP (“Sunoco”), Saturn Merger Sub, LLC (“Merger Sub”), Riverwalk Logistics, L.P., NuStar GP, LLC, and Sunoco GP LLC, and the transactions contemplated thereby, including the merger of Merger Sub with and into NuStar (the “Merger”) with NuStar surviving the Merger as a subsidiary of Sunoco;

Proposal 2: The Compensation Proposal: To approve, by a non-binding, advisory vote, the compensation that may be received by NuStar Managing GP’s named executive officers in connection with the Merger; and

Proposal 3: The Adjournment Proposal: To approve the adjournment of the NuStar Special Meeting, if necessary, to solicit additional proxies in favor of the Merger Proposal, if (i) there are holders of an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum at such meeting or (ii) there are insufficient votes at the time of such adjournment to approve the Merger Proposal.

The approval by NuStar Common Unitholders of the Merger Proposal is a condition to the completion of the Merger.

Other sections of the proxy statement/prospectus describe the proposals listed above in more detail, as well as other matters contemplated in connection with the Merger. Before voting, please carefully read the proxy statement/prospectus in its entirety, including the Merger Agreement and all other annexes, and including documents incorporated by reference, for further information relevant to the business to be transacted at the NuStar Special Meeting. In particular, see the section entitlted “The Merger Agreement,” for a description of the Merger Agreement and transactions contemplated thereby, including the Merger, and the section entitled “Risk Factors,” for an explanation of the risks associated with the Merger Agreement and the transactions contemplated thereby, including the Merger.

WHETHER OR NOT YOU PLAN TO PARTICIPATE IN THE NUSTAR SPECIAL MEETING, PLEASE FOLLOW THE INSTRUCTIONS ON YOUR PROXY CARD TO VOTE BY TELEPHONE, INTERNET OR MAIL AS PROMPTLY AS POSSIBLE. IF YOUR UNITS ARE HELD IN THE NAME OF A BROKER OR CUSTODIAN, PLEASE FOLLOW THE VOTING INSTRUCTIONS PROVIDED BY SUCH BROKER OR CUSTODIAN.

If you have any questions concerning the Merger Agreement or the transactions contemplated thereby, including the Merger, or the accompanying proxy statement/prospectus or would like additional copies, please contact NuStar’s proxy solicitation agent:

Morrow Sodali LLC

333 Ludlow Street, 5th Floor, South Tower

Stamford, Connecticut 06902

Unitholders may call toll-free: 1-800-662-5200 

Banks and Brokers may call collect: 1-203-658-9400

By email: NS@investor.morrowsodali.com

By order of the Board of Directors,

Steve Gilbert

Vice President, Assistant General Counsel and

Corporate Secretary

NuStar Energy L.P.

19003 IH-10 West

San Antonio, Texas 78257

[●], 2024

ADDITIONAL INFORMATION

This document, which forms part of a registration statement on Form S-4 filed with the U.S. Securities and Exchange Commission, constitutes a proxy statement of NuStar under Section 14(a) of the U.S. Securities Exchange Act of 1934, as amended, with respect to the solicitation of proxies for the special meeting of NuStar Common Unitholders, or any adjournment or postponement thereof, to, among other things, approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Merger. This document is also a prospectus of Sunoco under Section 5 of the U.S. Securities Act of 1933, as amended, with respect to Sunoco Common Units that may be issued to NuStar Common Unitholders in the Merger pursuant to the Merger Agreement.

As permitted under the rules of the SEC, this document incorporates by reference important business and financial information about NuStar and Sunoco from other documents filed with the SEC that are not included in or delivered with this document. Please read the section entitled “Where You Can Find More Information.” You can obtain any of the documents incorporated by reference into this document from the SEC’s website at www.sec.gov.

Copies of documents filed by Sunoco with the SEC are available at Sunoco’s website, www.sunocolp.com and are also available to you without charge upon your request in writing or by telephone from Sunoco at the following address and telephone number. Copies of documents filed by NuStar with the SEC are available at NuStar’s website, www.nustarenergy.com and are also available to you without charge upon your request in writing or by telephone from NuStar at the following address and telephone number. None of the information contained on the website of Sunoco or NuStar is incorporated by reference into this document.

Please note that copies of the documents provided to you will not include exhibits, unless the exhibits are specifically incorporated by reference into the documents or this document.

If you would like to request any documents, please do so no later than [●], 2024 in order to receive them before the NuStar Special Meeting.

If you have any questions concerning the Merger Agreement or the transactions contemplated thereby, including the Merger, or the accompanying proxy statement/prospectus or would like additional copies, please contact NuStar’s proxy solicitation agent.

The Solicitation Agent for the NuStar Special Meeting is:

Morrow Sodali LLC

333 Ludlow Street, 5th Floor, South Tower

Stamford, Connecticut 06902

You may obtain information regarding the NuStar Special Meeting

from the Solicitation Agent as follows:

Unitholders may call toll-free: 1-800-662-5200

Banks and Brokers may call collect: 1-203-658-9400

By email: NS@investor.morrowsodali.com

ABOUT THIS PROXY STATEMENT/PROSPECTUS

Sunoco has filed with the SEC a registration statement on Form S-4 (File No. 333-[●]), of which this proxy statement/prospectus forms a part. This proxy statement/prospectus constitutes the prospectus of Sunoco under Section 5 of the Securities Act with respect to Sunoco Common Units issuable to NuStar Common Unitholders in the Merger pursuant to the Merger Agreement. Additionally, this proxy statement/prospectus also constitutes a proxy statement under Section 14(a) of the Exchange Act, with respect to NuStar. It also constitutes a notice of meeting with respect to the NuStar Special Meeting. As permitted by SEC rules, this proxy statement/prospectus does not contain all of the information included in the registration statement or in the exhibits or schedules to the registration statement. You may obtain a copy of the registration statement, including any amendments, schedules and exhibits, at the SEC’s website mentioned above. Statements contained in this proxy statement/prospectus as to the contents of any contract or other documents referred to in this proxy statement/prospectus are not necessarily complete. In each case, you should refer to the copy of the applicable agreement or other document filed as an exhibit to the registration statement.

Information contained in or incorporated by reference into this proxy statement/prospectus relating to NuStar has been supplied by NuStar. Information contained in this proxy statement/prospectus relating to Sunoco has been supplied by Sunoco.

You should rely only on the information contained in or incorporated by reference into this proxy statement/prospectus. 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/prospectus. This proxy statement/prospectus is dated [●], 2024, and you should assume that the information contained in this proxy statement/prospectus is accurate only as of such date. You should also assume that the information incorporated by reference into this proxy statement/prospectus is only accurate as of the date of such information. Neither the mailing of this proxy statement/prospectus to NuStar Common Unitholders nor the issuance by Sunoco of Sunoco Common Units pursuant to the Merger Agreement will create any implication to the contrary.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

All currency amounts referenced in this proxy statement/prospectus are in U.S. dollars. All references in this proxy statement/prospectus to:

TABLE OF CONTENTS

QUESTIONS AND ANSWERS

The following are questions that you may have regarding the Merger and other matters being considered at the NuStar Special Meeting and the answers to those questions. NuStar and Sunoco urge you to carefully read the entirety of this proxy statement/prospectus, including the annexes hereto and the information incorporated herein, because the information in this section does not provide all the information that might be important to you with respect to the Merger and other matters being considered at the NuStar Special Meeting.

Q: Why am I receiving these materials?

A: Sunoco and NuStar have entered into a Merger Agreement, pursuant to which Sunoco will acquire NuStar, and NuStar will cease to be a publicly held limited partnership (other than NuStar Preferred Units, which will remain outstanding immediately following the Merger). Upon the terms and subject to the conditions set forth in the Merger Agreement, at the Effective Time, Merger Sub will be merged with and into NuStar, with NuStar surviving the Merger as the Surviving Entity and a subsidiary of Sunoco.

In order to complete the Merger, NuStar Common Unitholders must vote to approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Merger. This document is being delivered to you as both a proxy statement of NuStar and a prospectus of Sunoco in connection with the Merger. It is the proxy statement by which the NuStar Managing GP Board is soliciting proxies from you to vote in favor of the Merger Proposal and other matters at the NuStar Special Meeting. It is also the prospectus for the offering by Sunoco of Sunoco Common Units in the Merger. This proxy statement/prospectus contains important information about the NuStar Special Meeting and the Merger Agreement and the transactions contemplated thereby, including the Merger, and you should carefully read this proxy statement/prospectus in its entirety.

Q: What am I being asked to consider and vote on?

A: NuStar Common Unitholders are being asked to consider and vote on the following proposals:

Q: How does the NuStar Managing GP Board recommend that I vote on the proposals being considered at the NuStar Special Meeting?

A: The NuStar Managing GP Board unanimously recommends that the NuStar Common Unitholders vote:

In considering the recommendation of the NuStar Managing GP Board with respect to the Merger Proposal, you should be aware that some of the NuStar Managing GP directors and executive officers have interests in the Merger that are different from, or in addition to, the interests of NuStar Common Unitholders generally. For more information see the section entitled “The Merger—Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger.”

1

Q: What will happen in the Merger?

A: The Merger Agreement provides for the merger of Merger Sub with and into NuStar, with NuStar surviving following the Merger as a subsidiary of Sunoco.

In connection with the Merger, each NuStar Common Unit issued and outstanding immediately prior to the Effective Time (other than Excluded Units and Sunoco Held Units) will be converted into and represent the right to receive 0.400 of a Sunoco Common Unit and, if applicable, cash in lieu of fractional units, with each person or entity so receiving Sunoco Common Units upon the exchange being admitted as a limited partner of Sunoco. No fractional Sunoco Common Units will be issued in the Merger. Instead, each holder of NuStar Common Units otherwise entitled to a fractional Sunoco Common Unit will be entitled to receive, subject to applicable withholding, a cash payment (without interest and rounded to the nearest cent) in lieu of any such fractional Sunoco Common Unit. For more information, see the section entitled “The Merger Agreement—Merger Consideration.”

In addition, prior to the Effective Time, NuStar will declare and pay the Special Distribution of $0.212 per NuStar Common Unit to the NuStar Common Unitholders.

Upon completion of the Merger, based on the number of Sunoco Common Units and NuStar Common Units as of the date of the Merger Agreement, the legacy NuStar Common Unitholders will own approximately 38% of the Sunoco Common Units, and legacy Sunoco Common Unitholders will own approximately 62% of the Sunoco Common Units.

Q: What will happen to NuStar equity awards in the Merger?

A: NuStar Restricted Unit Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Restricted Unit Award will become fully vested and will be cancelled and converted into the right to receive (i) a number of Sunoco Common Units equal to the product of (A) the number of NuStar Common Units subject to such NuStar Restricted Unit Award immediately prior to the Effective Time, multiplied by (B) the Exchange Ratio and (ii) a cash payment equal to the product of (A) the number of NuStar Common Units subject to such NuStar Restricted Unit Award immediately prior to the Effective Time multiplied by (B) the per-unit amount of the Special Distribution.

NuStar Performance Cash Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Performance Cash Award will become fully vested and will be cancelled and converted into the right to receive an amount in cash equal to 200% of the target amount of cash pursuant to such NuStar Performance Cash Award, except that for each NuStar Performance Cash Award that constitutes a carry forward award, the cash amount will equal 100% of the target amount.

NuStar Time-Vesting Cash Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Time-Vesting Cash Award will become fully vested and will be cancelled and converted into the right to receive an amount in cash equal to 100% of the amount of cash subject to such NuStar Time-Vesting Cash Award.

Q: What will happen to NuStar Preferred Units in the Merger?

A: Nothing. Each NuStar Preferred Unit issued and outstanding immediately prior to the Effective Time will remain issued and outstanding from and after the Effective Time as a limited partnership interest of the Surviving Entity, having the same terms as are applicable to such NuStar Preferred Unit immediately prior to the Effective Time. The Surviving Entity intends to effect the Preferred Redemption to redeem the NuStar Preferred Units following the Effective Time, with the proceeds of the Debt Financing. However, there can be no assurance that Sunoco will be able to consummate the Debt Financing or that it will receive sufficient proceeds therefrom to enable NuStar to effect the Preferred Redemptions. In addition, there can be no assurance that Sunoco will cause the proceeds of the Debt Financing to be contributed to NuStar to enable NuStar to effect the Preferred Redemptions or that the Preferred Redemptions may be completed in the absence of such contribution.

2

Q: If I am a NuStar Common Unitholder, will I receive distributions in the future?

A: During the pendency of the Merger, NuStar may continue to make quarterly distributions of up to $0.400 per NuStar Common Unit to the NuStar Common Unitholders. In addition, NuStar will make the Special Distribution.

To the extent that your NuStar Common Units are exchanged for Sunoco Common Units in connection with the completion of the Merger and you continue to hold your newly acquired Sunoco Common Units, you will receive distributions declared by the Sunoco GP Board and paid by Sunoco going forward, in accordance with the Sunoco Partnership Agreement. For a description of the distribution provisions of the Sunoco Partnership Agreement, please read the section entitled “Comparison of Rights of NuStar Common Unitholders and Sunoco Common Unitholders.”

Q: When and where will the NuStar Special Meeting be held?

A: The NuStar Special Meeting will be held virtually at www.virtualshareholdermeeting.com/NS2024SM on [    ], 2024, starting at [    ] Central Time (unless it is adjourned or postponed to a later date).

The NuStar Special Meeting can be accessed by visiting www.virtualshareholdermeeting.com/NS2024SM, where NuStar Common Unitholders will be able to participate and vote online during the NuStar Special Meeting. NuStar encourages its Common Unitholders to access the meeting early—approximately 15 minutes before the start of the meeting. Please follow the instructions as outlined in this proxy statement/prospectus.

Q: What vote of NuStar Common Unitholders is required to approve the proposals at the NuStar Special Meeting?

A: Approval of the Merger Proposal requires the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units. Any failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online), abstentions or broker non-vote will have the same effect as a vote “AGAINST” the Merger Proposal.

Approval of the Compensation Proposal requires the affirmative vote of the holders of at least a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting, assuming a quorum is present. Abstentions will have the same effect as a vote “AGAINST” the Compensation Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Compensation Proposal.

Approval of the Adjournment Proposal requires the affirmative vote of the holders of at least a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting. Abstentions will have the same effect as a vote “AGAINST” the Adjournment Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Adjournment Proposal.

Q: How do I vote at the NuStar Special Meeting?

A: NuStar Common Unitholders must enter the 16-digit control number found on their proxy card or voting instruction form. Once properly admitted to the NuStar Special Meeting, NuStar Common Unitholders may vote their units by following the instructions available on the meeting website during the meeting. If you experience technical difficulties, you may contact the technical support number at 844-986-0822 (U.S.) and 303-562-9302 (International).

You may vote online at the NuStar Special Meeting or by submitting a proxy. NuStar Common Unitholders who hold NuStar Common Units through a broker or custodian (“street name” unitholders) who wish to vote at the NuStar Special Meeting should be provided a 16-digit control number or voting instruction form by the broker or

3

custodian that holds their NuStar Common Units. If you are a “street name” NuStar Common Unitholder and cannot locate your control number, please contact the broker or custodian that holds your NuStar Common Units of record.

Regardless of whether you plan to participate in the NuStar Special Meeting, it is important that your NuStar Common Units be represented and voted at the NuStar Special Meeting. Accordingly, NuStar encourages you to vote in advance of the NuStar Special Meeting.

Q: How do I submit a proxy for the NuStar Special Meeting?

A: Voting instructions are included on your proxy card. If you properly give your proxy and submit it to NuStar in time for it to be voted, one of the individuals named as your proxy will vote your units as you have directed. You may vote for or against the proposals or abstain from voting.

You can submit your proxy the following ways:

Q: What constitutes a quorum for the NuStar Special Meeting?

A: A quorum for purposes of the NuStar Special Meeting consists of the holders of record of at least a majority of the issued and outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting. There must be a quorum for the NuStar Special Meeting to be held. In the absence of a quorum at the NuStar Special Meeting, the affirmative vote of holders of at least a majority of the outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting may adjourn the NuStar Special Meeting to a later date and time (subject to applicable law and compliance with the terms of the NuStar Partnership Agreement).

Q: Who is entitled to vote at the NuStar Special Meeting?

A: The record date for determining NuStar Common Unitholders entitled to receive notice of, and to vote at, the NuStar Special Meeting or at any adjournment or postponement thereof, is the close of business on [    ], 2024. Only holders of record at the close of business on the record date are entitled to vote at the NuStar Special Meeting.

4

Q: How important is my vote as a NuStar Common Unitholder?

A: Your vote “FOR” each proposal presented at the NuStar Special Meeting is very important, and you are encouraged to submit a proxy as soon as possible. The Merger cannot be completed without the approval of the Merger Proposal by the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units.

Q: How many votes do I have for the NuStar Special Meeting?

A: Each NuStar Common Unitholder is entitled to one vote for each NuStar Common Unit held of record as of the close of business on the record date for each proposal.

Q: Who counts the votes?

A: NuStar has engaged Broadridge Investor Communication Solutions as its independent agent, to receive and tabulate votes at the NuStar Special Meeting. A representative of Broadridge Investor Communication Solutions will separately tabulate “FOR,” “AGAINST” or “ABSTAIN” votes, as applicable. A representative of Broadridge Investor Communication Solutions has also been retained to be NuStar’s inspector of votes to determine the existence of a quorum, determine the validity of proxies, certify the results and perform any other acts required under Delaware law and the NuStar Partnership Agreement.

Q: How will my NuStar Common Units be voted if I return a blank proxy?

A: If you sign, date and return your proxy card and do not indicate how you want your NuStar Common Units to be voted, then your NuStar Common Units will be voted “FOR” the Merger Proposal, “FOR” the Compensation Proposal and “FOR” the Adjournment Proposal.

Q: If my NuStar Common Units are held in “street name” by my broker or custodian, will my broker or custodian vote my units without instructions from me?

A: No. Because it is expected that all of the matters to be voted on at the NuStar Special Meeting will be non-routine under NYSE rules, brokers and custodians will not have discretionary authority to vote on any such proposal; therefore, if you do not provide voting instructions to your broker or custodian, your units will not count towards determining whether a quorum is present and your units will not be voted on any of the proposals.

Q: If I am planning on virtually attending the NuStar Special Meeting, should I still submit a proxy?

A: Yes. Whether or not you plan to virtually attend the NuStar Special Meeting, you should submit a proxy in advance by internet, telephone or mail.

If you do later attend the NuStar Special Meeting and wish to change your vote, you may do so at the meeting.

Q: What do I do if I want to revoke or change my vote?

A: If you submit a completed proxy card with instructions on how to vote your NuStar Common Units and then wish to revoke your instructions, you may do so by internet, telephone or mail at any time before it is voted by:

5

Q: What should I do if I receive more than one set of voting materials for the NuStar Special Meeting?

A: You may receive more than one set of voting materials for the NuStar Special Meeting and the materials may include multiple proxy cards or voting instruction forms. For example, you will receive a separate voting instruction form from each broker or custodian with which you hold units. If you are a holder of record registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction form that you receive according to the instructions on it to ensure that all of your units are voted.

Q: How do I exchange my NuStar Common Units for the Merger Consideration?

A: Promptly after the Effective Time, the exchange agent will mail to each record holder of NuStar Common Units, which at the Effective Time were converted into the right to receive the Merger Consideration, (i) a letter of transmittal and (ii) instructions for use in effecting the surrender of the certificates or book-entry units in exchange for the Merger Consideration, cash in lieu of any fractional Sunoco Common Units or any distributions, without interest, with a record date occurring prior to the Effective Time. Such holders will be paid the Merger Consideration to which they are entitled upon the surrender to the exchange agent of such NuStar Common Units and a duly completed and validly executed letter of transmittal and any other documents required by the exchange agent.

Q: What happens if I fail to return a letter of transmittal sent by the exchange agent?

A: Eighteen months after the Effective Time, any NuStar Common Unitholders who have not surrendered such NuStar Common Units to the exchange agent in compliance with the Merger Agreement may thereafter look only to Sunoco for payment of their claim for the applicable Merger Consideration, any cash in lieu of fractional Sunoco Common Units, and any distributions payable pursuant to the Merger Agreement.

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

A: The record date of the NuStar Special Meeting is earlier than the date of the NuStar Special Meeting and the date that the Merger is expected to be completed. If you transfer your NuStar Common Units after the record date but before the date of the NuStar Special Meeting, you will retain your right to vote at the NuStar Special Meeting, but you will not have the right to receive the Merger Consideration to be received by NuStar Common Unitholders in the Merger. In order to receive the Merger Consideration, you must hold your NuStar Common Units through the Closing Date.

Q: What are the expected U.S. federal income tax consequences to a U.S. holder of NuStar Common Units as a result of the Merger?

A: In general, for U.S. federal income tax purposes, no gain or loss should be recognized by a U.S. holder (as defined below) of NuStar Common Units solely as a result of the receipt of Sunoco Common Units in exchange for NuStar Common Units pursuant to the Merger, other than gain or loss, if any, resulting from any (i) decrease in such NuStar Common Unitholder’s share of partnership liabilities pursuant to Section 752 of the Code, (ii) receipt of cash in lieu of a fractional Sunoco Common Unit in the Merger, (iii) actual or deemed distributions of cash or property by Sunoco or (iv) actual or deemed sale of Sunoco Common Units pursuant to the withholding provisions of the Merger Agreement.

For a more detailed discussion of the material U.S. federal income tax consequences of the Merger to U.S. holders of NuStar Common Units, please see the section entitled “Material U.S. Federal Income Tax Consequences of the Merger.”

6

Q: What are the expected U.S. federal income tax consequences to a NuStar Common Unitholder of ownership of Sunoco Common Units?

A: Each NuStar Common Unitholder who becomes a Sunoco Common Unitholder as a result of the Merger will, as is the case for existing Sunoco Common Unitholders, be allocated such holder’s distributive share of Sunoco’s income, gains, losses, deductions and credits. In addition to U.S. federal income taxes, such holder may be subject to other taxes, including state and local income taxes, unincorporated business taxes, and estate, inheritance or intangibles taxes that may be imposed by the various jurisdictions in which Sunoco conducts business or owns property following the Merger or in which the holder is a resident.

For a more detailed discussion of the material U.S. federal income tax consequences of Sunoco Common Unit ownership following the Merger, please see the section entitled “Material U.S. Federal Income Tax Consequences of Sunoco Common Unit Ownership.”

Q: Do I have appraisal or dissenters’ rights?

A: Under the Delaware LP Act and the NuStar Partnership Agreement, NuStar Common Unitholders do not have rights to an appraisal of the fair value of their NuStar Common Units in connection with the Merger.

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

A: Yes. The respective obligations of each of NuStar and Sunoco to consummate the Merger are subject to the satisfaction at or prior to the Closing of numerous conditions, including, among other things, approval by NuStar Common Unitholders of the Merger Proposal, no injunction or law prohibiting the Merger and the expiration or termination of all waiting periods (and any extension thereof) applicable to the transaction under the HSR Act, and the termination or expiration of any commitment to, or agreement with, any governmental authority not to consummate the Closing before a certain date. For more information, see the section entitled “The Merger Agreement—Conditions to the Merger.”

Q: When do you expect to consummate the Merger?

A: Sunoco and NuStar currently expect to complete the Merger in the second quarter of 2024, subject to the receipt of required NuStar Unitholder Approval and regulatory approvals and the satisfaction or waiver of the other conditions to completion of the Merger. Because many of the conditions to completion of the Merger are beyond the control of Sunoco and NuStar, the exact timing for completion of the Merger cannot be predicted with any degree of certainty.

Q: What happens if the Merger is not completed?

A: If the NuStar Common Unitholders do not approve the Merger Proposal or if the Merger is not completed for any other reason, NuStar Common Unitholders will not receive any Merger Consideration for their NuStar Common Units in connection with the Merger. NuStar would remain an independent partnership and the NuStar Common Units would continue to be listed and traded on the NYSE. In addition, under specified circumstances, NuStar may be required to pay Sunoco a Breakup Fee of $90,272,205 in connection with termination of the Merger Agreement as described in the section entitled “The Merger Agreement—NuStar Breakup Fee.”

Q: What happens if the Compensation Proposal is not approved by the NuStar Common Unitholders?

A: The Compensation Proposal is a vote separate and apart from the vote to approve and adopt the Merger Agreement, and approval of the Compensation Proposal is not a condition to the completion of the Merger. Accordingly, you may vote to approve the Compensation Proposal and vote not to approve and adopt the Merger Agreement and vice versa and failure to pass the Compensation Proposal will not prevent the completion of the

7

Merger from occurring. Because the vote is advisory in nature only, it will not be binding on either NuStar or Sunoco. Accordingly, to the extent that NuStar or Sunoco is contractually obligated to pay the compensation, the compensation will be payable to the named executive officers, subject only to the conditions applicable thereto, if the Merger Agreement is approved and adopted and the Merger is completed, regardless of the outcome of the Compensation Proposal.

Q: Are there any risks in the Merger, or otherwise in connection with the Merger Agreement, that I should consider?

A: Yes. There are risks associated with all business combinations, including the Merger. Before making any decision on how to vote, NuStar and Sunoco urge you to read carefully and in its entirety this proxy statement/prospectus and the section entitled “Risk Factors.” You are also encouraged to read and carefully consider the risk factors relating to NuStar and Sunoco contained in the documents incorporated by reference into this proxy statement/prospectus, including NuStar’s Annual Report on Form 10-K for the year ended December 31, 2023 and Sunoco’s Annual Report on Form 10-K for the year ended December 31, 2023.

Q: Who can I contact with questions about the NuStar Special Meeting and related matters?

A: If you have any questions about the NuStar Special Meeting and how to submit your proxy or voting instruction form or if you need additional copies of this proxy statement/prospectus or the enclosed proxy card or voting instruction form, you should contact NuStar’s proxy solicitation agent, Morrow Sodali LLC, by email at NS@investor.morrowsodali.com. NuStar Common Unitholders may also call toll-free at 1-800-662-5200. Banks and brokers may call collect at 1-203-658-9400.

You may also contact NuStar, Attention: Investor Relations, 19003 IH-10 West, San Antonio, Texas 78257, telephone: (210) 918-4687.

Questions regarding matters presented at the NuStar Special Meeting may be submitted during the meeting through the meeting’s website at www.virtualshareholdermeeting.com/NS2024SM. Additional information regarding rules and procedures for participating in the virtual meeting will be provided in the meeting rules of conduct, which you will be able to view during the meeting on the meeting website.

8

9

10

11

12

13

14

15

16

17

18

19

20

21

RISK FACTORS

In addition to the other information included and incorporated by reference into this document, including the matters addressed in the section entitled “Cautionary Statement Regarding Forward-Looking Statements,” you should carefully consider the following risks before deciding whether to vote for the approval and adoption of the Merger Agreement and the transactions contemplated thereby, including the Merger. In addition, you should read and consider the risks associated with each of the businesses of Sunoco and NuStar. These risks can be found in Sunoco’s and NuStar’s respective Annual Reports on Form 10-K for the year ended December 31, 2023, filed with the SEC and incorporated by reference into this proxy statement/prospectus. For further information regarding the documents incorporated into this document by reference, please see the section entitled “Where You Can Find More Information.” Realization of any of the risks described below, any of the events described under the section entitled “Cautionary Statement Regarding Forward-Looking Statements” or any of the risks or events described in the documents incorporated by reference could have a material adverse effect on Sunoco’s, NuStar’s or the combined partnership’s business, financial condition, cash flows and results of operations and could result in a decline in the trading prices of their respective common units.

Risk Factors Related to the Merger

Because the Exchange Ratio is fixed, the number of Sunoco Common Units to be received by NuStar Common Unitholders in connection with the Merger will not change between now and the time the Merger is completed to reflect changes in the trading prices of NuStar Common Units or Sunoco Common Units. Because the market price of Sunoco Common Units will fluctuate prior to the consummation of the Merger, NuStar Common Unitholders cannot be sure of the market value of Sunoco Common Units that they will receive as Merger Consideration.

Pursuant to the Merger Agreement and by virtue of the Merger, each NuStar Common Unit issued and outstanding immediately prior to the Effective Time (other than any Excluded Units and Sunoco Held Units) will be converted into and will thereafter represent the right to receive 0.400 of a Sunoco Common Unit. No fractional Sunoco Common Units will be issued in the Merger, but in lieu thereof, each holder of NuStar Common Units otherwise entitled to a fractional Sunoco Common Unit will be entitled to receive, subject to applicable withholding, a cash payment (without interest and rounded to the nearest cent) in lieu of any such fractional Sunoco Common Unit in an amount equal to the product of (i) the volume-weighted average closing price of one Sunoco Common Unit as reported on the NYSE for the ten consecutive full trading days ending at the close of trading on the full trading day immediately preceding the Closing Date and (ii) the fraction of a Sunoco Common Unit that such holder would otherwise be entitled to receive pursuant to the Merger Agreement.

The Exchange Ratio is fixed (subject to adjustments in accordance with the terms of the Merger Agreement), which means that it will not change between now and the Closing Date, regardless of whether the market price of either NuStar Common Units or Sunoco Common Units change. At the time that NuStar Common Unitholders cast their votes regarding the Merger Proposal, NuStar Common Unitholders will not know the actual market value of the Sunoco Common Units that they will receive when the Merger is completed. Therefore, the actual market value of the Sunoco Common Units, when received by NuStar Common Unitholders, will depend on the market value of Sunoco Common Units on that date. This market value may be less than the value of the Sunoco Common Units on the date of the Merger Agreement and on the date that NuStar Common Unitholders vote on the Merger Proposal. These fluctuations in the market value of Sunoco Common Units may be caused by changes in the businesses, operations, results and prospects of both Sunoco and NuStar, market expectations of the likelihood that the Merger will be completed and the timing of the completion, general market and economic conditions or other factors.

22

The Merger is subject to a number of conditions to the obligations of both NuStar and Sunoco to complete the Merger, including approval by NuStar Common Unitholders and regulatory clearance, which may impose unacceptable conditions or could delay completion of the Merger or result in termination of the Merger Agreement.

The respective obligations of each of NuStar and Sunoco to consummate the Merger are subject to the satisfaction at or prior to the Closing of numerous conditions, including, among other things, approval by NuStar Common Unitholders of the Merger Proposal, no injunction or law prohibiting the Merger and the expiration or termination of all waiting periods (and any extension thereof) applicable to the transaction under the HSR Act, and the termination or expiration of any commitment to, or agreement with, any governmental authority not to consummate the Closing before a certain date. Many of the conditions to the completion of the Merger are not within either NuStar’s or Sunoco’s control, and NuStar cannot predict when, or if, these conditions will be satisfied. Furthermore, the requirement for obtaining the required regulatory clearances could delay the completion of the Merger for a significant period of time or prevent it from occurring. Regulators may seek to enjoin the completion of the Merger, seek divestiture of substantial assets of the parties, or require the parties to license, or hold separate, assets or terminate existing relationships and contractual rights.

Any delay in completing the Merger could cause the combined partnership not to realize, or delay the realization of, some or all of the benefits that are expected to be achieved from the Merger. In such context, the date on which the NuStar Common Unitholders will receive the Merger Consideration is also uncertain.

If the Merger Proposal is approved by the NuStar Common Unitholders, the date that the NuStar Common Unitholders will receive the Merger Consideration is still uncertain.

As described in this proxy statement/prospectus, completing the Merger is subject to several conditions, not all of which are controllable or waivable by NuStar or Sunoco. Accordingly, if the Merger Proposal is approved by NuStar Common Unitholders, the date that NuStar Common Unitholders will receive the Merger Consideration depends on the completion date of the Merger, which is uncertain.

Certain executive officers and directors of NuStar Managing GP have interests in the Merger that are different from, or in addition to, the interests of NuStar Common Unitholders generally, which could have influenced their decision to support or approve the Merger.

Certain executive officers and directors of NuStar Managing GP are parties to agreements or participants in other arrangements that give them interests in the Merger that may be different from, or be in addition to, your interests as a NuStar Common Unitholder. The NuStar Managing GP Board was aware of and carefully considered these interests, among other matters, in evaluating the terms and structure, overseeing the negotiation, approving the Merger Agreement and the transactions contemplated thereby, including the Merger, and in recommending that the NuStar Common Unitholders vote in favor of the Merger Proposal, the Compensation Proposal and the Adjournment Proposal. You should consider these interests in voting on the Merger Proposal. NuStar has described these different interests in the section entitled “The Merger—Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger.”

NuStar or Sunoco may waive one or more of the closing conditions without re-soliciting approval by NuStar Common Unitholders.

Sunoco or NuStar may determine to waive, in whole or part, one or more of the conditions to Closing prior to Sunoco or NuStar, as the case may be, being obligated to consummate the Merger. Each of Sunoco and NuStar expects to evaluate the materiality of any proposed waiver and its effect on its respective unitholders in light of the facts and circumstances at the time, to determine whether any amendment of this proxy statement/prospectus or any re-solicitation of proxies is required in light of such waiver. Any determination whether to waive any condition to the Closing or to re-solicit unitholder approval or amending or supplementing this proxy statement/prospectus as a result of a waiver will be made by Sunoco or NuStar at the time of such waiver based on the facts and circumstances as they exist at that time.

23

The Merger Agreement limits NuStar’s ability to pursue alternatives to the Merger.

The Merger Agreement contains provisions that make it more difficult for NuStar to sell its business to a party other than Sunoco. Specifically, each of Sunoco and NuStar have agreed not to (and have agreed to cause its respective directors, officers and subsidiaries and their respective directors and officers not to, as well as to instruct their other officers and employees, accountants, consultants, investment bankers, financial advisors or other representatives acting on their behalf not to), among other restrictions, directly or indirectly, solicit, initiate, propose, knowingly facilitate or knowingly encourage any acquisition proposals or any proposal, inquiry or offer that would reasonably be expected to lead to, result in or constitute an acquisition proposal. Additional non-solicitation limitations are described in the section entitled “The Merger Agreement—Non-Solicitation of Alternative Transactions.” NuStar would also be required to pay Sunoco a Breakup Fee of $90,272,205 if, among other circumstances, the NuStar Managing GP Board were to terminate the Merger Agreement in order for NuStar to enter into a superior proposal, should one be made. Please see the section entitled “The Merger Agreement—NuStar Breakup Fee” for additional details. The foregoing may discourage a third party that might have an interest in acquiring all or a significant part of NuStar from considering or proposing an acquisition, even if that party were prepared to pay consideration with a higher per unit value than the collective value of the current proposed Merger Consideration and Special Distribution.

Notwithstanding the aforementioned restrictions, the Merger Agreement provides that, in certain circumstances where NuStar receives a proposal prior to obtaining the NuStar Unitholder Approval that the NuStar Managing GP Board determines in good faith (after consultation with its outside legal counsel and financial advisor) constitutes a superior proposal, then NuStar may (i) furnish any information regarding, or afford access to the business, properties, assets, books or records of NuStar to the person making such acquisition proposal and (ii) engage in discussions and negotiations with any person in response to an unsolicited, bona fide, written acquisition proposal. However, each of Sunoco and NuStar have also agreed to (i) promptly notify the other party in writing, and in any event within one business day of receipt, of any acquisition proposal, and which will identify the material terms and conditions thereof (and, thereafter, any material change to the terms thereof) and the third party making such acquisition proposal; and (ii) keep the other party reasonably informed on a reasonably current basis of the status and any material developments (including all material amendments or material proposed amendments, whether or not in writing) regarding any acquisition proposal or any material change to the terms of any such acquisition proposal.

If a governmental authority asserts objections to the Merger, Sunoco or NuStar may be unable to complete the Merger or, in order to do so, Sunoco or NuStar may be required to comply with material restrictions or satisfy material conditions.

The Closing is subject to the condition that there is no temporary restraining order, preliminary or permanent injunction or other writ, injunction, judgment or decree preventing the consummation of the Merger and no statute, rule, regulation or order deemed applicable to the Merger that makes consummation of the Merger illegal. Pursuant to the Merger Agreement and subject to the terms and conditions set forth therein, Sunoco and NuStar has agreed to use reasonable best efforts to promptly take, or cause to be taken, all actions, and to do all things necessary, proper or advisable under applicable regulatory laws to consummate and make effective the Merger and the other transactions contemplated by the Merger Agreement.

There can be no assurance as to the cost, scope or impact of the actions that may be required to address any governmental authority objections to the Merger. If Sunoco or NuStar takes such actions, it could be detrimental to it or to the combined partnership following the consummation of the Merger. Furthermore, these actions could have the effect of delaying or preventing consummation of the transactions, including the Merger, or imposing additional costs on or limiting the revenue or cash available for distribution of the combined partnership following the consummation of the Merger. There are also limitations in the Merger Agreement on the actions Sunoco is required to take in order to address any governmental authority objections to the Merger; so, depending on the nature of the governmental authority objections to the Merger, Sunoco may decline to agree to

24

take such actions resulting in the failure of the Merger to be completed. For more information, see the section entitled “The Merger—Regulatory Approvals.”

If the Merger Agreement is terminated, under certain circumstances, NuStar may be obligated to pay a Breakup Fee to Sunoco. This cost could require NuStar to seek loans or use cash on hand that would have otherwise been available for operations, distributions or other general partnership purposes.

NuStar may be obligated to pay a Breakup Fee to Sunoco of $90,272,205 if the Merger Agreement is terminated, under certain circumstances. For more information, see the section entitled “The Merger Agreement—NuStar Breakup Fee.” This Breakup Fee may require NuStar to seek loans, borrow or use available cash to enable it to pay Sunoco, which would reduce the cash NuStar has available for operations, distributions or other general partnership purposes.

NuStar’s and Sunoco’s financial estimates are based on various assumptions that may not prove to be correct.

The financial estimates set forth in the forecast included in the section entitled “The Merger—NuStar and Sunoco Unaudited Prospective Financial Information Reviewed by the NuStar Managing GP Board and Barclays” are based on assumptions of, and information available to, NuStar and Sunoco at the time they were prepared and provided to the NuStar Managing GP Board and its financial advisors. NuStar and Sunoco do not know whether such assumptions will prove correct. Any or all of such estimates may turn out to be wrong. Such estimates can be adversely affected by inaccurate assumptions or by known or unknown risks and uncertainties, many of which are beyond NuStar’s and Sunoco’s control. Many factors discussed in, or in documents incorporated by reference into, this proxy statement/prospectus, including the risks outlined in this “Risk Factors” section and the events or circumstances described under “Cautionary Statement Regarding Forward-Looking Statements,” will be important in determining NuStar’s and Sunoco’s future results. As a result of these contingencies, actual future results may vary materially from NuStar’s and Sunoco’s estimates.

In view of these uncertainties, the inclusion of NuStar’s financial estimates in this proxy statement/prospectus is not and should not be viewed as a representation that the forecast results will be achieved. Further, any forward-looking statement speaks only as of the date on which it is made, and NuStar and Sunoco undertake no obligation, other than as required by applicable law, to update the financial estimates herein to reflect events or circumstances after the date those financial estimates were prepared or to reflect the occurrence of anticipated or unanticipated events or circumstances. Moreover, neither NuStar’s nor Sunoco’s independent accountants, nor any other independent accountants, have compiled, examined or performed any procedures with respect to NuStar’s or Sunoco’s unaudited prospective financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information or achievability thereof.

The opinion of NuStar’s financial advisor does not and will not reflect changes in circumstances between the signing of the Merger Agreement and the Closing Date.

The NuStar Managing GP Board received an opinion from NuStar’s financial advisor in connection with the signing of the Merger Agreement. Please refer to the section entitled “The Merger—Opinion of NuStar’s Financial Advisor” for additional information. However, NuStar has not obtained any updated opinion from its financial advisor as of the date of this proxy statement/prospectus. Changes in the operations and prospects of NuStar or Sunoco, general market and economic conditions and other factors that may be beyond the control of NuStar or Sunoco, and on which the financial advisor’s opinion was based, may significantly alter the value of NuStar or Sunoco or the prices of their respective units by the time the Merger is completed. The opinion does not speak as of the time the Merger will be completed or as of any date other than the date of such opinion. Because NuStar does not currently anticipate asking its financial advisor to update its opinion, such opinion will not address the fairness of the Exchange Ratio, Merger Consideration or Special Distribution from a financial point of view at the time the Merger is completed or as of the date of this proxy statement/prospectus. The NuStar Managing GP Board’s recommendation that NuStar Common Unitholders vote in favor of the Merger

25

Proposal, the Compensation Proposal and the Adjournment Proposal, however, are made as of the date of this proxy statement/prospectus.

The unaudited pro forma combined financial information and other financial forecasts contained in this proxy statement/prospectus may not be an indication of the combined partnership’s results of operations or financial condition following the Closing.

This proxy statement/prospectus includes certain financial forecasts considered by NuStar and Sunoco in connection with their respective businesses as well as unaudited pro forma combined financial information for the combined partnership, which gives effect to the Merger. This information should be read in conjunction with NuStar’s reported financial results and Sunoco’s reported financial results, which can be found in NuStar’s and Sunoco’s most recent SEC filings as described in the section entitled “Where You Can Find More Information.” The unaudited pro forma combined financial information and other financial forecasts contained in this proxy statement/prospectus should not be considered to be an indication of the combined partnership’s results of operations or financial condition following the Closing. The unaudited pro forma combined financial information and other financial forecasts have been derived from the historical financial statements of NuStar and Sunoco, and adjustments, assumptions, and preliminary estimates have been made in connection with the preparation of this information. These kinds of adjustments, assumptions and estimates are difficult to make with accuracy and may not prove accurate. These forecasts are also subject to significant economic, competitive, industry and other uncertainties and contingencies, all of which are difficult or impossible to predict and many of which are beyond the control of NuStar and Sunoco. Important factors that may affect the actual results of NuStar and Sunoco and cause the internal financial forecasts to not be achieved include risks and uncertainties relating to NuStar’s and Sunoco’s businesses, industry performance, the regulatory environment, general business and economic conditions and other factors described under the section entitled “Cautionary Statement Regarding Forward-Looking Statements” in this proxy statement/prospectus. Accordingly, the unaudited pro forma combined financial information and other financial forecasts should not be assumed to be indicative of what NuStar’s, Sunoco’s or the combined partnership’s financial condition, results of operations, or cash flows actually would have been as standalone entities or be a reliable indicator of what the combined partnership’s financial condition or results of operations may actually be in the future.

Moreover, the unaudited pro forma combined financial information does not reflect all costs that are expected to be incurred by the combined partnership in connection with the Merger. For example, the impact of any incremental costs incurred in coordinating the operations of NuStar and Sunoco are not reflected in the unaudited pro forma combined financial information. In addition, the unaudited pro forma combined financial information does not include, among other things, certain estimated cost synergies, adjustments related to restructuring or integration activities, future acquisitions or disposals not yet known or probable, or effects of merger-related change in control provisions that are currently not factually supportable or probable of occurring. As a result, the actual results of operations and financial condition of the combined partnership following the Closing may not be consistent with, or evident from, the unaudited pro forma combined financial information. The assumptions used in preparing the unaudited pro forma combined financial information may not prove to be accurate, and other factors may affect the combined partnership’s results of operations or financial condition following the Closing.

NuStar Common Unitholders are not entitled to appraisal or dissenters’ rights in connection with the Merger.

Appraisal rights are statutory rights that enable unitholders to dissent from certain extraordinary transactions, such as certain mergers, and to demand that a partnership pay the fair value for their units as determined by a court in a judicial proceeding instead of receiving the consideration offered to unitholders in connection with the applicable transaction. Under the Delaware LP Act and the NuStar Partnership Agreement, NuStar Common Unitholders will not have rights to an appraisal of the fair value of their NuStar Common Units in connection with the Merger. See the section entitled “The Merger Agreement—No Dissenters’ or Appraisal Rights” for additional details.

26

Failure to complete the Merger could have a negative impact on the price of NuStar’s and Sunoco’s publicly traded units and have a material adverse effect on NuStar’s and Sunoco’s results of operations, cash flows and financial position.

If the Merger is not completed for any reason, including as a result of failure to obtain all requisite regulatory and unitholder approvals, the ongoing business of NuStar and Sunoco may be materially and adversely affected and, without realizing any of the benefits of having completed the Merger, NuStar and Sunoco would be subject to a number of risks, including the following:

In addition, if the Merger Agreement is terminated under certain circumstances specified therein, NuStar may be required to pay Sunoco a Breakup Fee of $90,272,205.

If the Merger is not completed, the risks described above may materialize and they may have a material adverse effect on NuStar’s and Sunoco’s results of operations, cash flows, financial position and the price of their publicly-traded units.

The announcement and pendency of the Merger may adversely affect NuStar’s business, financial results and operations.

Whether or not the Merger is completed, the announcement and pendency of the Merger could cause disruptions to NuStar’s and Sunoco’s respective businesses, including:

The announcement and pendency of the Merger may cause a loss of management personnel and other key employees of NuStar and Sunoco, which could adversely affect the future business and operations of the combined partnership following the Merger.

NuStar and Sunoco are dependent on the experience and industry knowledge of their officers and other key employees to execute their business plans. Sunoco’s success after the Merger will depend in part upon its ability to retain key management personnel and other key employees. Current and prospective employees of NuStar and Sunoco may experience uncertainty about their roles within the combined partnership following the Merger or other concerns regarding the timing and completion of the Merger or the operations of the combined partnership

27

following the Merger, any of which may have an adverse effect on the ability of NuStar and Sunoco to retain or attract key management and other key personnel. If NuStar or Sunoco are unable to retain personnel, including NuStar or Sunoco’s key management, who are critical to the future operations of the companies, NuStar and Sunoco could face disruptions in their operations, loss of existing customers, loss of key information, expertise, or know-how, and unanticipated additional recruitment and training costs. In addition, the loss of key NuStar and Sunoco personnel could diminish the anticipated benefits of the Merger. No assurance can be given that the combined partnership, following the Merger, will be able to retain or attract key management personnel and other key employees of NuStar and Sunoco to the same extent that NuStar and Sunoco have previously been able to retain or attract their own employees.

The announcement and pendency of the Merger may cause disruption to the business relationships of NuStar and Sunoco due to the uncertainty associated with the Merger, which could adversely affect the future operations, cash flows and financial position of the combined partnership following the Merger.

Parties with which NuStar and Sunoco do business may experience uncertainty associated with the Merger, including with respect to current or future business relationships with NuStar and Sunoco following the Merger. NuStar’s and Sunoco’s business relationships may be subject to disruption as customers, distributors, suppliers, vendors, landlords, joint venture partners and other business partners may attempt to delay or defer entering into new business relationships, negotiate changes in existing business relationships or consider entering into business relationships with parties other than the combined partnership following the Merger. These disruptions could have a material and adverse effect on the results of operations, cash flows and financial position of NuStar and Sunoco, regardless of whether the Merger is completed, as well as a material and adverse effect on the combined partnership’s ability to realize the expected cost savings and other benefits of the Merger.

The combined partnership may fail to realize the anticipated benefits of the Merger and fail to successfully integrate the businesses and operations of the parties in the expected time frame.

The success of the Merger depends on, among other things, the successful combination of NuStar’s and Sunoco’s businesses in a manner that realizes anticipated synergies and benefits and meets or exceeds the forecasted stand-alone cost savings anticipated by the combined business. If the combined partnership is not able to successfully achieve these synergies, or the cost to achieve these synergies is greater than expected, then the anticipated benefits of the Merger may not be realized fully or at all or may take longer to realize than expected. If the transaction closes, it is possible that the integration process could result in the loss of key NuStar employees or key Sunoco employees, the loss of customers, providers, vendors or business partners, the disruption of either or both parties’ ongoing businesses, inconsistencies in standards, controls, procedures, and policies, potential unknown liabilities and unforeseen expenses, delays, regulatory conditions associated with and following the Closing Date or higher than expected integration costs and an overall post-completion integration process that takes longer than originally anticipated.

In addition, at times the attention of certain members of the NuStar Managing GP’s management and resources may be focused on the completion of the Merger and planning the anticipated integration, and diverted from day-to-day business operations or other opportunities that may have been beneficial to NuStar, which may disrupt NuStar’s ongoing business and the post-Closing operations of the combined partnership.

NuStar and Sunoco may be subject to litigation challenging the Merger, and an unfavorable judgment or ruling in any such lawsuits could prevent or delay the consummation of the Merger and/or result in substantial costs.

Lawsuits related to the Merger may be filed against NuStar, Sunoco and its respective affiliates, directors and officers. If dismissals are not obtained or a settlement is not reached, these lawsuits could prevent or delay completion of Merger and/or result in substantial costs to NuStar. Securities class action lawsuits and derivative lawsuits are often brought against publicly listed companies and partnerships that have entered into merger

28

agreements. Even if the lawsuits are without merit, defending against these claims can result in substantial costs and divert management time and resources. An adverse judgment could result in monetary damages, which could have a negative impact on NuStar and Sunoco. Lawsuits could also seek, among other things, injunctive relief or other equitable relief, including a request to rescind parts of the Merger Agreement already implemented and to otherwise enjoin the parties from consummating the Merger. One of the conditions to the Closing is that there is no temporary restraining order, preliminary or permanent injunction or other writ, injunction, judgment or decree preventing the consummation of the Merger and no statute, rule, regulation or order deemed applicable to the Merger that makes consummation of the Merger illegal. For a detailed discussion of the terms and conditions of the Merger, see the section entitled “The Merger Agreement—Conditions to the Merger.” Consequently, if a plaintiff is successful in obtaining an injunction prohibiting completion of the Merger, then that injunction may delay or prevent the Merger from being completed, which may adversely affect NuStar’s and Sunoco’s business, financial position and results of operation. There can be no assurance that any of the defendants will be successful in the outcome of any pending or any potential future lawsuits. The defense or settlement of any lawsuit or claim that remains unresolved at the time the Merger is completed may adversely affect NuStar’s and Sunoco’s respective businesses, financial condition, results of operations and cash flows.

NuStar and Sunoco will incur substantial transaction-related costs in connection with the Merger, including fees paid to financial, legal and accounting advisors, filing fees and printing costs.

NuStar and Sunoco expect to incur a number of non-recurring costs associated with negotiating the Merger Agreement and consummating the transactions contemplated thereby, including the Merger, combining the operations of the two partnerships and achieving the desired synergies

The combined partnership may record goodwill and other intangible assets that could become impaired and result in material non-cash charges to the results of operations of the combined partnership in the future.

The combined partnership will account for the Merger as an acquisition of a business in accordance with GAAP. Under the acquisition method of accounting, the assets and liabilities of NuStar will be recorded, as of completion, at their respective fair values and added to Sunoco’s. The combined partnership’s reported financial condition and results of operations for periods after completion of the Merger will reflect NuStar’s balances and results after completion of the Merger but will not be restated retroactively to reflect the historical financial position or results of operations of NuStar for periods prior to the Merger.

Under the acquisition method of accounting, the total purchase price is allocated to NuStar’s identifiable tangible and intangible assets acquired and liabilities assumed based on their respective fair values as of the Closing Date, with any excess purchase price allocated to goodwill. To the extent the value of goodwill or intangibles, if any, becomes impaired in the future, the combined partnership may be required to incur material non-cash charges relating to such impairment. The combined partnership’s operating results may be significantly impacted from both the impairment and the underlying trends in the business that triggered the impairment.

Each of NuStar and Sunoco may have liabilities that are not known to the other party.

Each of NuStar and Sunoco may have liabilities that the other party failed, or was unable, to discover in the course of performing its respective due diligence investigations. NuStar and Sunoco may learn additional information about the other party that materially adversely affects it, such as unknown or contingent liabilities and liabilities related to compliance with applicable laws. As a result of these factors, the combined partnership may incur additional costs and expenses and may be forced to later write-down or write-off assets, restructure operations or incur impairment or other charges that could result in the combined partnership reporting losses. Even if NuStar’s and Sunoco’s due diligence has identified certain risks, unexpected risks may arise and previously known risks may materialize in a manner not consistent with its preliminary risk analysis. If any of these risks materialize, this could have a material adverse effect on the combined partnership’s financial condition and results of operations and could contribute to negative market perceptions about Sunoco Common Units.

29

A different set of factors and conditions than those that affect NuStar Unitholders affect Sunoco Unitholders and could have a negative impact on the Sunoco Common Unit price following the Closing Date.

Upon the Closing Date, each NuStar Common Unitholder that receives Sunoco Common Units upon the exchange of NuStar Common Units for the Merger Consideration will be admitted as a limited partner of Sunoco. The businesses of Sunoco are different in many respects from those of NuStar. There is a risk that various factors, conditions and developments that would not affect the price of NuStar Common Units could negatively affect the price of Sunoco Common Units. Accordingly, the future market price and performance of Sunoco Common Units is likely to be different from that of the historical market price and performance of NuStar Common Units. Please see the section entitled “Cautionary Statement Regarding Forward-Looking Statements” for a summary of some of the key factors that might affect Sunoco and the prices at which Sunoco Common Units may trade from time to time.

The market price for Sunoco Common Units following the Closing may be affected by factors different from those that historically have affected or currently affect Sunoco Common Units and NuStar Common Units.

Upon Closing, NuStar Common Unitholders will receive Sunoco Common Units. Sunoco’s financial position may differ from its financial position before the completion of the Merger, and the results of operations of the combined partnership may be affected by some factors that are different from those currently affecting the results of operations of Sunoco and those currently affecting the results of operations of NuStar. Accordingly, the market price and performance of Sunoco Common Units is likely to be different from the performance of Sunoco Common Units or NuStar Common Units in the absence of the Merger.

The trading price and volume of Sunoco Common Units, which NuStar Common Unitholders will receive in connection with the Merger, may be volatile following the Merger.

The trading price and volume of Sunoco Common Units, which NuStar Common Unitholders will receive in connection with the Merger, may be volatile following completion of the Merger. The equity markets in general have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. These broad market fluctuations may adversely affect the trading price of Sunoco Common Units. As a result, NuStar Common Unitholders who receive Sunoco Common Units may suffer a loss on their investment. Many factors may impair the market for Sunoco Common Units following the Merger and the ability of investors to sell units at an attractive price and could also cause the market price and demand for Sunoco Common Units to fluctuate substantially following the Merger, which may negatively affect the price and liquidity of Sunoco Common Units following the Merger. The market for Sunoco Common Units will depend on a number of factors and conditions, many of which are beyond the control of Sunoco or NuStar or their respective unitholders, including:

30

Future sales or issuances of Sunoco Common Units could have a negative impact on the Sunoco Common Unit price.

The Sunoco Common Units that NuStar Common Unitholders will receive upon the exchange of NuStar Common Units for the Merger Consideration generally may be sold immediately in the public market. It is possible that some NuStar Common Unitholders may decide to sell some or all of the Sunoco Common Units that they receive as Merger Consideration. Any disposition of a significant number of Sunoco Common Units, or the perception in the market that such dispositions could occur, may cause the price of Sunoco Common Units to fall. Any such decline could impair the combined partnership’s ability to raise capital through future sales of Sunoco Common Units.

NuStar Common Unitholders and Sunoco Common Unitholders will be significantly diluted by the Merger.

The Merger and Unit Issuance will result in (i) NuStar Common Unitholders having an ownership stake in Sunoco that will be less than their current stake in NuStar and (ii) Sunoco Common Unitholders having an

31

ownership stake in Sunoco that will be less than their current stake in Sunoco before the Closing Date. Based on the trading prices of NuStar Common Units and Sunoco Common Units as of the date of the Merger Agreement, following the Closing Date, NuStar Common Unitholders are expected to own approximately 38% and Sunoco Common Unitholders are expected to own approximately 62% of the combined partnership’s common units. Consequently, both NuStar Common Unitholders and Sunoco Common Unitholders will, as a general matter, have less influence over the management and policies of the combined partnership as compared to their influence over NuStar and Sunoco, respectively.

In addition, Sunoco has IDRs outstanding that entitle Energy Transfer, as the sole holder of the issued and outstanding IDRs, to receive certain distributions from Sunoco, which reduces the cash available for distributions to Sunoco Common Unitholders. For more information, please see the section entitled “Description of Sunoco Common Units—Incentive Distribution Rights.”

Sunoco expects to obtain financing in connection with the Redemptions and cannot guarantee that it will be able to obtain such financing on favorable terms or at all.

Sunoco currently expects to finance the Redemptions using Debt Financing, as further described in “Summary—Description of Committed Debt Financing.” Sunoco’s ability to obtain any such Debt Financing will depend on, among other factors, prevailing market conditions and other factors beyond Sunoco’s control. Sunoco cannot assure you that it will be able to obtain Debt Financing on terms acceptable to it or at all. As a result, Sunoco may need to pursue other options, including borrowings under the Bridge Facility, which may result in less favorable financing terms that could increase costs and/or adversely impact the operations of Sunoco. Completion of the Merger is not conditioned on obtaining such Debt Financing.

Completion of the Merger may trigger change in control provisions under the notes indentures to which NuStar is a party.

The consummation of the Merger may trigger change in control provisions in the notes indentures to which NuStar and its subsidiaries are parties. The indentures and other agreements governing NuStar’s $600.0 million principal amount outstanding of 5.75% senior notes due 2025, $500.0 million principal amount outstanding of 6.00% senior notes due 2026, $550.0 million principal amount outstanding of 5.625% senior notes due 2027, $600.0 million principal amount outstanding of 6.375% senior notes due 2030, $55.44 million principal amount outstanding of Parish of St. James, State of Louisiana Revenue Bonds (NuStar Logistics, L.P. Project) Series 2008, $100.0 million principal amount outstanding of Parish of St. James, State of Louisiana Revenue Bonds (NuStar Logistics, L.P. Project) Series 2010, $43.3 million of principal amount outstanding of Parish of St. James, State of Louisiana Revenue Bonds (NuStar Logistics, L.P. Project) Series 2010A, $48.4 million of principal amount outstanding of Parish of St. James, State of Louisiana Revenue Bonds (NuStar Logistics, L.P. Project) Series 2010B and $75.0 million of principal amount outstanding of Parish of St. James, State of Louisiana Revenue Bonds (NuStar Logistics, L.P. Project) Series 2011 (collectively, the “NuStar Notes”) require NuStar Logistics, L.P. to make an offer to repurchase the NuStar Notes at a purchase price in cash equal to 101% of the aggregate principal amount of notes repurchased, plus accrued and unpaid interest, within 30 days of the occurrence of a change of control transaction. A “change of control” transaction, as defined under the NuStar Notes indentures, occurs when, among other things, a transaction is consummated and, as a result, any person (other than certain affiliates of NuStar) becomes the beneficial owner of more than 50% of NuStar Logistics, L.P., NuStar, or their respective general partner’s, voting stock (as defined in the applicable indenture). However, such transaction is not a “change of control” transaction unless it is followed by a ratings decline of the applicable notes within 60 days of the change of control. If the combined partnership does not have sufficient funds to redeem all NuStar Notes that holders tender for purchase upon the occurrence of a change of control, and is unable to raise additional capital, an event of default could occur under the indentures. An event of default could cause other debt to become automatically due, further exacerbating the combined partnership’s financial condition and diminishing the value and liquidity of the NuStar Notes. If any such “change of control” transaction were to occur in connection with the Merger and the holders of the NuStar Notes accept any offer of

32

repurchase of their notes, such repurchase could significantly affect the liquidity, business, liabilities and financial condition of the combined partnership following the completion of the Merger.

The combined partnership may not be able to retain customers or suppliers, and customers or suppliers may seek to modify contractual obligations with the combined partnership, either of which could have an adverse effect on the combined partnership’s business and operations. Completion of the Merger may trigger change in control or third parties may terminate or alter existing agreements to which Sunoco or NuStar is a party.

As a result of the Merger, the combined partnership may experience adverse effects on relationships with customers and suppliers that may harm the combined partnership’s business and results of operations. Certain customers or suppliers may seek to terminate or modify contractual obligations following the Merger whether or not contractual rights are triggered as a result of the Merger. There can be no guarantee that customers and suppliers will remain with or continue to have a relationship with the combined partnership or do so on the same or similar contractual terms following the Merger.

Additionally, the completion of the Merger may trigger change in control or other provisions in certain agreements to which Sunoco or NuStar is a party. If Sunoco or NuStar are unable to negotiate waivers of those provisions, the counterparties may exercise their rights and remedies under such agreements, potentially terminating such agreements, or seeking monetary damages. Even if Sunoco or NuStar are able to negotiate waivers, the counterparties may require a fee for such waivers or seek to renegotiate such agreements on terms less favorable to the combined partnership. If any customers or suppliers seek to terminate or modify contractual obligations or discontinue their relationships with the combined partnership, then the combined partnership’s business and results of operations may be harmed. If the combined partnership’s suppliers were to seek to terminate or modify an arrangement with the combined partnership, then the combined partnership may be unable to procure necessary supplies or services from other suppliers in a timely and efficient manner and on acceptable terms, or at all. In addition, third parties with whom NuStar or Sunoco currently have relationships may terminate or otherwise reduce the scope of their relationship with either party in anticipation of the Merger.

Any such disruptions could adversely impact Sunoco’s ability to achieve the anticipated benefits of the Merger. The adverse effect of such disruptions could also be exacerbated by a delay in the completion of the Merger, or the termination of the Merger Agreement.

Sunoco’s future debt levels may impair its financial condition and its ability to make distributions to Sunoco Common Unitholders.

Sunoco had $3.6 billion of debt outstanding as of December 31, 2023. Sunoco has the ability to incur additional debt under its revolving credit facility and the indentures governing Sunoco’s senior notes. In connection with the Merger, Sunoco expects to assume an additional aggregate $4.2 billion of indebtedness. The level of Sunoco’s future indebtedness could have important consequences to the combined partnership, including:

33

In addition, the combined partnership may not be able to generate sufficient cash flow from its operations to repay its indebtedness when it becomes due and to meet other cash needs. The combined partnership’s ability to service its debt depends upon, among other things, its financial and operating performance as impacted by prevailing economic conditions, and financial, business, regulatory and other factors, some of which will be beyond its control. In addition, the combined partnership’s ability to service its debt will depend on market interest rates, since the rates applicable to a portion of its borrowings fluctuate. If the combined partnership is not able to pay its debts as they become due, it will be required to pursue one or more alternative strategies, such as selling assets, refinancing or restructuring its indebtedness or selling additional debt or equity securities. The combined partnership may not be able to refinance its debt or sell additional debt or equity securities or its assets on favorable terms, if at all, and if the combined partnership must sell its assets, it may negatively affect its ability to generate revenues.

The unitholders of the combined partnership may experience dilution in the future.

The percentage ownership of the combined partnership’s unitholders may be diluted in the future because of equity issuances for acquisitions, capital market transactions or otherwise, including, without limitation, equity awards that the combined partnership may grant to its directors, officers and employees. Such issuances may have a dilutive effect on the combined partnership’s earnings per unit, which could adversely affect the market price of the Sunoco Common Units.

The Sunoco Common Units to be received by NuStar Common Unitholders as a result of the Merger will have different rights than the NuStar Common Units.

Following the Closing Date, NuStar Common Unitholders will no longer hold NuStar Common Units and will instead be Sunoco Common Unitholders. There are important differences between the rights of NuStar Common Unitholders and Sunoco Common Unitholders.

NuStar Common Unitholders will lose certain rights that they had as NuStar Common Unitholders after the completion of the Merger. For example, NuStar Common Unitholders currently have the right to vote in the election of the NuStar Managing GP Board and other matters affecting NuStar. Sunoco Common Unitholders are not entitled to elect the directors of Sunoco GP and have only limited voting rights on matters affecting Sunoco’s business.

In addition, Sunoco’s Partnership Agreement limits the liability and duties of Sunoco GP, while also restricting the remedies available to Sunoco Common Unitholders for actions that, without these limitations, might constitute breaches of fiduciary duty under Delaware law. Among other things, the Sunoco Partnership Agreement permits Sunoco GP to make a number of decisions in its individual capacity, as opposed to its capacity as general partner of Sunoco, which entitles Sunoco GP to consider only the interests and factors that it desires, with no duty or obligation to give consideration to the interests of, or factors affecting, the Sunoco Common Unitholders. Such decisions made by Sunoco GP in its individual capacity are made by Energy Transfer, as the owner of Sunoco GP, and not by the Sunoco GP Board.

See the section entitled “Comparison of Rights of NuStar Common Unitholders and Sunoco Common Unitholders” for a discussion of the different rights associated with NuStar Common Units and Sunoco Common Units.

34

The NYSE does not require a publicly traded partnership like Sunoco to comply with certain corporate governance requirements.

The NYSE does not require publicly traded partnerships like Sunoco to have a majority of independent directors on Sunoco GP’s Board or to establish a compensation committee or a nominating and corporate governance committee. Accordingly, NuStar Common Unitholders who receive Sunoco Common Units as a result of the Merger will not have the same corporate governance protections that are afforded to stockholders of companies that are subject to all of the corporate governance requirements of the applicable stock exchange.

Tax Risks Related to the Merger

No ruling has been requested from the IRS with respect to the U.S. federal income tax consequences of the Merger.

No ruling has been or will be requested from the IRS with respect to the U.S. federal income tax consequences of the Merger. Instead, NuStar and Sunoco are relying on the opinions of their respective external counsel with respect to the U.S. federal income tax consequences of the Merger, and counsel’s conclusions may not be sustained if challenged by the IRS. For additional information, please read the section entitled “Material U.S. Federal Income Tax Consequences of the Merger.”

The intended U.S. federal income tax consequences of the Merger are dependent upon Sunoco being treated as a partnership for U.S. federal income tax purposes that would not be treated as an investment company (within the meaning of Section 351 of the Code) if the partnership were incorporated.

The intended U.S. federal income tax treatment of the Merger is dependent upon Sunoco being treated as a partnership for U.S. federal income tax purposes at the time of the Merger that would not be treated as an investment company (within the meaning of Section 351 of the Code) if Sunoco were incorporated. If Sunoco were treated as a corporation for U.S. federal income tax purposes at the time of the Merger or were treated as an investment company (within the meaning of Section 351 of the Code) if Sunoco were incorporated, the consequences of the Merger would be materially different and the Merger generally would be a taxable transaction to NuStar Common Unitholders. For additional information, please read the section entitled “Material U.S. Federal Income Tax Consequences of the Merger.”

The exchange of NuStar Common Units for Sunoco Common Units pursuant to the Merger may be taxable in certain circumstances.

In general, the exchange by a NuStar Common Unitholder of NuStar Common Units for Sunoco Common Units is expected to qualify as an exchange to which Section 721(a) of the Code applies, i.e., a transaction in which no gain or loss is recognized by a U.S. holder (as defined below) of NuStar Common Units for U.S. federal income tax purposes. However, under certain circumstances, a NuStar Common Unitholder may recognize gain upon such exchange or upon the occurrence of certain subsequent events or transactions undertaken by Sunoco. Specifically, the exchange of NuStar Common Units for Sunoco Common Units pursuant to the Merger will not qualify as a transaction in which no gain or loss is recognized for U.S. federal income tax purposes if, immediately after the Merger, Sunoco were characterized, for U.S. federal income tax purposes, as (i) a partnership that would be treated as an “investment company” if the partnership were incorporated, or (ii) a publicly traded partnership treated as a corporation. It is a condition to NuStar’s obligation to effect the Merger that (i) NuStar receive a written opinion from Wachtell, Lipton, Rosen & Katz (or another nationally recognized tax counsel as may be reasonably acceptable to NuStar) to the effect that, for U.S. federal income tax purposes, the exchange of NuStar Common Units for Sunoco Common Units pursuant to the Merger should be treated as an exchange described in Section 721(a) of the Code and (ii) Sunoco receive an opinion from Vinson & Elkins LLP (or another nationally recognized tax counsel as may be reasonably acceptable to Sunoco and NuStar) to the effect that (a) at least 90% of the gross income of Sunoco for all of the calendar year that immediately precedes the calendar year that includes the Closing Date and each calendar quarter of the calendar year that includes the Closing Date for which the necessary financial information is available is from sources treated as “qualifying

35

income” within the meaning of Section 7704(d) of the Code and (b) Sunoco should not be treated as an investment company for purposes of Section 721(b) of the Code. It is a condition to NuStar’s and Sunoco’s obligation to effect the Merger that (i) Sunoco receive a written opinion of Vinson & Elkins LLP (or another nationally recognized tax counsel as may be reasonably acceptable to Sunoco and NuStar) to the effect that at least 90% of the gross income of Sunoco and NuStar, calculated on a pro forma combined basis, for all of the calendar year that immediately precedes the calendar year that includes the Closing Date and each calendar quarter of the calendar year that includes the Closing Date for which the necessary financial information is available is from sources treated as “qualifying income” within the meaning of Section 7704(d) of the Code and (ii) NuStar receive a written opinion of Sidley Austin LLP (or another nationally recognized tax counsel as may be reasonably acceptable to Sunoco and NuStar) to the effect that at least 90% of the gross income of NuStar for all of the calendar year that immediately precedes the calendar year that includes the Closing Date and each calendar quarter of the calendar year that includes the Closing Date for which the necessary financial information is available is from sources treated as “qualifying income” within the meaning of Section 7704(d) of the Code. An opinion of counsel represents such counsel’s judgment and is not binding on the IRS or any court and the IRS or a court may disagree with the conclusion in an opinion of counsel.

For U.S. federal income tax purposes, each U.S. holder of NuStar Common Units should be deemed to contribute its NuStar Common Units to Sunoco in exchange for Sunoco Common Units and the deemed assumption by Sunoco of each such NuStar Common Unitholder’s share of NuStar’s nonrecourse liabilities. U.S. holders of NuStar Common Units should become limited partners of Sunoco upon receipt of Sunoco Common Units and should be allocated a share of Sunoco’s nonrecourse liabilities. Each NuStar Common Unitholder should be treated as receiving a deemed cash distribution equal to any net reduction in the amount of nonrecourse liabilities allocated to such NuStar Common Unitholder. If the amount of such deemed cash distribution received by a U.S. holder of NuStar Common Units exceeds such NuStar Common Unitholder’s tax basis in Sunoco Common Units immediately after the Merger, such NuStar Common Unitholder will recognize gain in an amount equal to such excess. 

In addition, as described below in the section entitled “Material U.S. Federal Income Tax Consequences of the Merger—Additional U.S. Federal Income Tax Considerations Relating to the Ownership of Sunoco Common Units Received in the Merger,” a U.S. holder of NuStar Common Units could be required to recognize part or all of the “built-in gain” in his NuStar Common Units exchanged for Sunoco Common Units in the Merger upon the occurrence of certain subsequent events or transactions undertaken by Sunoco.

Further, a U.S. holder of NuStar Common Units whose Sunoco Common Units are deemed to be sold to fulfill withholding obligations generally will recognize gain or loss equal to the difference, if any, between the fair market value of the Sunoco Common Units that are deemed to be sold and the holder’s adjusted tax basis allocable to such Sunoco Common Units.

For additional information, please read the section entitled “Material U.S. Federal Income Tax Consequences of the Merger.”

Tax Risks Related to Owning Sunoco Common Units Following the Merger

Holders of Sunoco Common Units received in the Merger will generally be subject to the tax risks that apply to existing Sunoco Common Unitholders, which may be different than those that currently affect NuStar Common Unitholders.

Following the Merger, holders of Sunoco Common Units received in the Merger, for U.S. federal income tax purposes, will generally be subject to the risks that current Sunoco Common Unitholders are currently subject to, which are described in Sunoco’s Annual Report on Form 10-K for the most recent fiscal year, as updated by any subsequent Quarterly Reports on Form 10-Q and the Current Reports on Form 8-K, each as filed with the SEC before the Closing Date and all of which are incorporated by reference into this proxy statement/prospectus. Such risks may be different than those that currently affect NuStar Common Unitholders. See the section entitled “Where You Can Find More Information” for the location of information incorporated by reference in this proxy statement/prospectus.

36

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This document includes “forward-looking statements” about Sunoco and NuStar that are subject to risks and uncertainties. All statements other than statements of historical fact included in this document are forward-looking statements. Statements using words such as “anticipate,” “believe,” “intend,” “project,” “plan,” “expect,” “continue,” “estimate,” “goal,” “forecast,” “may,” “could,” “will,” “predict,” “potential,” “should,” “would,” “seek,” or similar expressions help identify forward-looking statements.

Except for their respective obligations to disclose material information under U.S. federal securities laws, neither Sunoco nor NuStar undertakes any obligation to release publicly any revisions to any forward-looking statements, to report events or circumstances after the date of this document, or to report the occurrence of unanticipated events.

Forward-looking statements involve a number of risks and uncertainties, and actual results or events may differ materially from those projected or implied in those statements. Important factors that could cause such differences include, but are not limited to:

In addition, the acquisition of NuStar by Sunoco is subject to the satisfaction of certain conditions and the absence of events that could give rise to the termination of the Merger Agreement, the possibility that the Merger does not close, risks that the proposed Merger disrupts current plans and operations and business relationships or poses difficulties in attracting or retaining employees, the possibility that the costs or difficulties related to the integration of the two companies will be greater than expected and the possibility that the anticipated benefits from the Merger cannot or will not be fully realized.

All written and oral forward-looking statements attributable to Sunoco or NuStar or persons acting on behalf of Sunoco or NuStar are expressly qualified in their entirety by such factors. For additional information with respect to these factors, please see the section entitled “Where You Can Find More Information.”

37

INFORMATION ABOUT THE COMPANIES

Sunoco LP

Sunoco is a publicly traded Delaware master limited partnership, with operations that include the distribution of motor fuel to convenience stores, independent dealers, commercial customers and distributors located in more than 40 U.S. states and territories as well as refined product transportation and terminalling assets. Sunoco Common Units are traded on the NYSE under the symbol “SUN.”

Sunoco’s principal executive offices are located at 8111 Westchester Drive, Suite 400, Dallas, Texas 75225, and its telephone number is (214) 981-0700. Additional information about Sunoco and its subsidiaries is included in documents incorporated by reference into this proxy statement/prospectus. See also the section entitled “Where You Can Find More Information.”

Saturn Merger Sub, LLC

Saturn Merger Sub, LLC, a Delaware limited liability company, is a direct, wholly owned subsidiary of Sunoco. Saturn Merger Sub, LLC was formed by Sunoco solely for the purpose of engaging in the transactions contemplated by the Merger Agreement. Other than its entry into the Merger Agreement and corresponding obligations, Saturn Merger Sub, LLC has not conducted any business activities, has no assets, liabilities or obligations and has conducted its operations solely as contemplated by the Merger Agreement. Saturn Merger Sub LLC’s principal executive offices are located at 8111 Westchester Drive, Suite 400, Dallas, Texas 75225, and its telephone number is (214) 981-0700.

NuStar Energy L.P.

NuStar is a publicly traded Delaware master limited partnership based in San Antonio, Texas. As of December 31, 2023, NuStar’s assets included 9,490 miles of pipeline and 63 terminal and storage facilities, which provide approximately 49 million barrels of storage capacity. Its business is managed under the direction of the board of directors of NuStar GP, LLC, the general partner of NuStar’s general partner, Riverwalk Logistics, L.P., both of which are wholly owned subsidiaries of NuStar. NuStar Common Units are currently traded on the NYSE under the symbol “NS,” and NuStar Preferred Units are currently traded on the NYSE under the symbols “NSprA,” “NSprB” and “NSprC.”

NuStar’s principal executive offices are located at 19003 IH-10 West, San Antonio, Texas 78257, and its telephone number is (210) 918-2000. Additional information about NuStar and its subsidiaries is included in documents incorporated by reference into this proxy statement/prospectus. See also the section entitled “Where You Can Find More Information.”

38

SPECIAL MEETING OF NUSTAR COMMON UNITHOLDERS

This section contains information about the NuStar Special Meeting at which NuStar Common Unitholders will be asked to consider and vote on proposals to (i) approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Merger, (ii) approve, by a non-binding, advisory vote, the compensation that may be received by NuStar Managing GP’s named executive officers in connection with the Merger and (iii) approve the adjournment of the NuStar Special Meeting, if necessary, to solicit additional proxies in favor of the Merger Proposal if (i) there are holders of an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum at such meeting or (ii) there are insufficient votes at the time of such adjournment to approve the Merger Proposal. This document is being furnished to NuStar Common Unitholders in connection with the solicitation of proxies by the NuStar Managing GP Board to be used at the NuStar Special Meeting.

Date, Time and Place of the Special Meeting

A virtual NuStar Special Meeting will be held at www.virtualshareholdermeeting.com/NS2024SM on [    ], 2024, starting at [    ] Central Time (unless it is adjourned or postponed to a later date).

The NuStar Special Meeting can be accessed by visiting www.virtualshareholdermeeting.com/NS2024SM, where NuStar Common Unitholders will be able to participate and vote online during the NuStar Special Meeting. NuStar encourages its Common Unitholders to access the meeting early—approximately 15 minutes before the start of the meeting. Please follow the instructions as outlined in this proxy statement/prospectus.

Participating in the Special Meeting

Holders of record of NuStar Common Units at the close of business on [    ], 2024 are entitled to attend and vote on the matters presented at the NuStar Special Meeting.

To be admitted to the NuStar Special Meeting, NuStar Common Unitholders must enter the 16-digit control number found on their proxy card or voting instruction form. Once properly admitted to the NuStar Special Meeting, NuStar Common Unitholders may vote their units by following the instructions available on the meeting website during the meeting. If you experience technical difficulties, you may contact the technical support number at 844-986-0822 (U.S.) and 303-562-9302 (International).

Questions regarding matters presented at the NuStar Special Meeting may be submitted during the meeting through the meeting’s website. Additional information regarding rules and procedures for participating in the virtual meeting will be provided in the meeting rules of conduct, which you will be able to view during the meeting on the meeting website.

Purpose of the Special Meeting

39

Recommendation of the NuStar Managing GP Board

The NuStar Managing GP Board has unanimously (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of NuStar and its unitholders, (ii) approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger, (iii) approved the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended approval and adoption of the Merger Agreement by the NuStar Common Unitholders and (v) directed that the Merger Agreement be submitted to the NuStar Common Unitholders for approval and adoption.

The NuStar Managing GP Board unanimously recommends that the holders of NuStar Common Units vote “FOR” the Merger Proposal, “FOR” the Compensation Proposal and “FOR” the Adjournment Proposal.

NuStar Common Unitholders should carefully read this document in its entirety for more detailed information concerning the Merger Agreement and the transactions contemplated thereby, including the Merger. In particular, NuStar Common Unitholders are directed to the Merger Agreement, which is attached hereto as Annex A.

Record Date; Unitholders Entitled to Vote

The record date for determining NuStar Common Unitholders entitled to receive notice of, and to vote at, the NuStar Special Meeting or at any adjournment or postponement thereof, is the close of business on [    ], 2024. Only holders of record at the close of business on the record date are entitled to vote at the NuStar Special Meeting.

As of the record date, there were [    ] NuStar Common Units entitled to vote at the NuStar Special Meeting.

Quorum

A “quorum” for purposes of the NuStar Special Meeting consists of the holders of record of at least a majority of the issued and outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting. There must be a quorum for the NuStar Special Meeting to be held. In the absence of a quorum at the NuStar Special Meeting, the affirmative vote of holders of at least a majority of the outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting may adjourn the NuStar Special Meeting to a later date and time (subject to applicable law and compliance with the terms of the NuStar Partnership Agreement).

If you submit a timely, properly executed proxy or voting instruction form, then you will be considered part of the quorum so long as your units are voted on at least one item of business, other than a procedural motion. Abstentions will be counted for purposes of determining whether there is a quorum at the NuStar Special Meeting. A broker non-vote occurs when a beneficial owner does not provide voting instruction to their broker or custodian with respect to a proposal on which such broker or custodian does not have discretionary authority to vote. Because it is expected that all of the matters to be voted on at the NuStar Special Meeting will be non-routine under NYSE rules, brokers will not have discretionary authority to vote on any such proposal; therefore, if you are a beneficial owner of NuStar Common Units and do not provide voting instructions to your broker or custodian, your NuStar Common Units will not count towards determining whether a quorum is present and your NuStar Common Units will not be voted on any of the proposals.

Failure to Vote; Abstentions; Broker Non-Votes

A failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) occurs when a NuStar Common Unitholder is not present online or by proxy at the NuStar Special Meeting.

40

An abstention occurs when a NuStar Common Unitholder is present for purposes of a quorum by virtually attending the NuStar Special Meeting and either does not vote or submits a ballot marked “abstain.” An abstention also occurs when a NuStar Common Unitholder does not attend the NuStar Special Meeting and instead submits a proxy with an “abstain” instruction. Abstentions will be counted for purposes of determining whether there is a quorum at the NuStar Special Meeting.

Under the rules that govern brokers who have record ownership of NuStar Common Units that they hold in street name for their clients who are the beneficial owners of the NuStar Common Units, brokers have the discretion to vote such NuStar Common Units on routine matters, but not on non-routine matters, including the Merger Proposal, the Compensation Proposal and the Adjournment Proposal, absent direction from the NuStar Common Unitholder. Broker non-votes occur when NuStar Common Units held by a broker are not voted with respect to a proposal because (i) the broker has not received voting instructions from the beneficial owner, and (ii) the broker lacks the authority to vote the NuStar Common Units at his or her discretion. Because it is expected that all of the matters to be voted on at the NuStar Special Meeting will be non-routine under NYSE rules, brokers and custodians will not have discretionary authority to vote on any such proposal; therefore, if you do not provide voting instructions to your broker or custodian, your NuStar Common Units will not count towards determining whether a quorum is present and your NuStar Common Units will not be voted on any of the proposals.

Because approval of the Merger Proposal requires the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units, the failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online), any abstention by a NuStar Common Unitholder and a broker non-vote will have the same effect as a vote “AGAINST” approval of the Merger Proposal.

Because approval of the Compensation Proposal requires the affirmative vote of the holders of at least a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting, assuming a quorum is present, abstentions are counted as units present and entitled to vote and will have the same effect as votes “AGAINST” the Compensation Proposal. A failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) and a broker non-vote will have no effect on the approval of the Compensation Proposal.

Because approval of the Adjournment Proposal requires the affirmative vote of the holders of at least a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting, assuming a quorum is present, abstentions are counted as units present and entitled to vote and will have the same effect as votes “AGAINST” the Adjournment Proposal. A failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) and a broker non-vote will have no effect on the approval of the Adjournment Proposal.

Required Vote

Approval of the Merger Proposal requires the affirmative vote of the holders of a majority of the outstanding NuStar Common Units. Any failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online), abstention or broker non-vote will have the same effect as a vote “AGAINST” the Merger Proposal.

Approval of the Compensation Proposal requires the affirmative vote of the holders of at least a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting, assuming a quorum is present. Abstentions will have the same effect as a vote “AGAINST” the Compensation Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Compensation Proposal.

Approval of the Adjournment Proposal requires the affirmative vote of the holders of a majority of the NuStar Common Units present online or by proxy at the NuStar Special Meeting. Abstentions will have the same

41

effect as a vote “AGAINST” the Adjournment Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Adjournment Proposal.

Units Beneficially Owned by Directors and Executive Officers

As of February 21, 2024, the members of the NuStar Managing GP Board and the executive officers of NuStar Managing GP beneficially owned an aggregate of 1,550,621 NuStar Common Units. This represents approximately 1.2% of the total voting power of NuStar Common Units. For more information, please see the section entitled “The Merger—Securities Ownership of Certain Beneficial Owners and Management.”

Proxies

You may vote online at the NuStar Special Meeting or by submitting a proxy via internet, telephone or mail. Please submit your proxy even if you plan to attend the NuStar Special Meeting.

Voting instructions are included on your proxy card. If you properly give your proxy and submit it to NuStar in time for it to be voted, one of the individuals named as your proxy will vote your units as you have directed. You may vote for or against the proposals or abstain from voting.

Units Held in Street Name

NuStar Common Unitholders who hold NuStar Common Units through a broker or custodian (“street name” unitholders) who wish to vote at the NuStar Special Meeting should be provided a 16-digit control number or voting instruction form by the broker or custodian that holds their NuStar Common Units. If you are a “street name” NuStar Common Unitholder and this has not occurred, contact the broker or custodian that holds your NuStar Common Units of record. A number of banks and brokerage firms participate in a program that also permits “street name” NuStar Common Unitholders to direct their vote by telephone or over the internet. If your NuStar Common Units are held in an account at a bank or brokerage firm that participates in such a program, you may direct the vote of these NuStar Common Units by telephone or over the internet by following the voting instructions enclosed with the voting instruction form from the bank or brokerage firm. The internet and telephone procedures are designed to authenticate NuStar Common Unitholders’ identities, to allow NuStar Common Unitholders to give their voting instructions and to confirm that those instructions have been properly recorded. Votes directed by telephone or over the internet through such a program must be received by 11:59 pm Eastern Time, on the day before the NuStar Special Meeting. Directing the voting of your NuStar Common Units will not affect your right to vote at the NuStar Special Meeting if you decide to attend the NuStar Special Meeting; however, you must use the 16-digit control number set forth on the voting instruction form received from your broker or custodian to vote your NuStar Common Units held in “street name” at the NuStar Special Meeting. Voting at the NuStar Special Meeting using the 16-digit control number set forth on the voting instruction form received from your broker or custodian prior to the deadline described above will automatically cancel any voting directions you have previously given by telephone or over the internet with respect to your NuStar Common Units.

Absent specific instructions from you, your broker or custodian is not empowered to vote your NuStar Common Units at the NuStar Special Meeting. Because it is expected that all of the matters to be voted on at the NuStar Special Meeting will be non-routine under NYSE rules, brokers and custodians will not have discretionary authority to vote on any such proposal; therefore, if you do not provide voting instructions to your broker or custodian, your units will not count towards determining whether a quorum is present and your units will not be voted on any of the proposals.

How to Submit Your Proxy

By Mail: If you are a NuStar Common Unitholder of record, you can submit your proxy by mail by marking your proxy, dating and signing it and returning it in the postage-paid envelope provided. If the envelope is

42

missing, please address your completed proxy card to the address on your proxy card. If you are a beneficial owner, please refer to your voting instruction form provided to you by your broker or custodian.

By Telephone: If you are a NuStar Common Unitholder of record, you can submit your proxy by telephone by calling the toll-free telephone number on your proxy card. Telephone voting is available 24 hours a day and will be accessible until 11:59 p.m. Eastern Time of the day prior to the NuStar Special Meeting. Easy-to-follow voice prompts allow you to submit your proxy and confirm that your instructions have been properly recorded. If you are a beneficial owner, please refer to your voting instruction form provided by your broker or custodian for information on whether telephone voting is offered. If you submit your proxy by telephone, you do not need to return your proxy card. If you are located outside the United States, Canada and Puerto Rico, please read your proxy card or other materials for additional instructions.

By Internet: If you are a NuStar Common Unitholder of record, you can submit your proxy online at the website indicated on your proxy card. Internet voting is available 24 hours a day and will be accessible until 11:59 p.m. Eastern Time of the day prior to the NuStar Special Meeting. If you are a beneficial owner, please refer to your voting instruction form provided by your broker or custodian for information on whether internet voting is offered. As with telephone voting, you will be given the opportunity to confirm that your instructions have been properly recorded. If you submit your proxy online, you do not need to return your proxy card.

Revoking Your Proxy

If you submit a completed proxy card with instructions on how to vote your NuStar Common Units and then wish to revoke your instructions, you may do so by internet, telephone or mail at any time before it is voted by:

Adjournments and Postponements

Any adjournment of the NuStar Special Meeting, if necessary, to (i) solicit additional proxies in favor of the Merger Proposal or (ii) if there are holders of an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum at the NuStar Special Meeting, requires the affirmative vote of the holders of at least a majority of the NuStar Common Units, present online or by proxy at the NuStar Special Meeting. No notice of the adjourned NuStar Special Meeting will be given so long as the time and place to which the NuStar Special Meeting is adjourned are announced at the NuStar Special Meeting at which the adjournment is taken, the adjournment is for no more than 45 days, a new record date is not fixed and, at the adjourned NuStar Special Meeting, only such business is transacted as might have been transacted at the original NuStar Special Meeting.

In addition, at any time prior to convening the NuStar Special Meeting, the NuStar Special Meeting may be postponed without the approval of NuStar Common Unitholders. If postponed, NuStar will publicly announce the new meeting date. Similar to adjournments, any postponement of the NuStar Special Meeting for the purpose of soliciting additional proxies will allow NuStar Common Unitholders who have already sent in their proxies to revoke them at any time prior to their use.

Proxy Solicitation

Sunoco and NuStar will each bear their own costs related to the Merger and the retention of any information agent or other service provider in connection with the Merger, except for the expenses incurred in connection

43

with the filing, printing and mailing of this document, which will be borne by Sunoco. This proxy solicitation is being made by NuStar on behalf of the NuStar Managing GP Board. NuStar has retained Morrow Sodali LLC to aid in the solicitation of proxies for an initial fee of $35,000 plus an additional fee for each NuStar Common Unitholder contacted and the reimbursement of out-of-pocket expenses. Morrow Sodali LLC may solicit proxies by personal interview, mail, telephone and electronic communications. In addition to this mailing, solicitations may also be made by personal interview, mail, telephone and electronic communications by directors, officers or employees of NuStar or its affiliates without additional compensation. Arrangements also will be made with brokerage houses and other custodians, nominees and fiduciaries for the forwarding of proxy materials to the beneficial owners of NuStar Common Units held by those persons, and NuStar will reimburse them for any reasonable expenses that they incur.

Householding of Special Meeting Materials

SEC rules allow companies to send a single notice or single copy of annual reports, proxy statements and other disclosure documents to two or more unitholders sharing the same address, subject to certain conditions. These “householding” rules are intended to provide convenience for unitholders and cost savings for companies by reducing the number of duplicate documents that unitholders receive. Only one copy of this proxy statement/prospectus is being delivered to multiple unitholders sharing the same address unless NuStar has received contrary instructions. If your units are held by an intermediary broker or custodian in “street name,” your consent to householding may be sought, or may already have been sought, by or on behalf of the intermediary.

If your units are held in a brokerage account and you no longer wish to participate in householding, or if you are receiving multiple copies of this proxy statement/prospectus and wish to receive only one, please notify your broker or custodian. If you hold units registered in your name and you no longer wish to participate in householding, or if you are receiving multiple copies of this proxy statement/prospectus and wish to receive only one, you can notify NuStar by sending a written request to NuStar’s Corporate Secretary at the address indicated on the cover page of this proxy statement/prospectus or emailing corporatesecretary@nustarenergy.com. NuStar will deliver promptly upon written or oral request a separate copy of this proxy statement/prospectus to any unitholder who previously participated in householding and no longer wishes to do so.

44

PROPOSAL 1: THE MERGER PROPOSAL

NuStar is requesting the NuStar Common Unitholders approve and adopt the Merger Agreement and the transactions contemplated thereby, including the Merger. For a detailed discussion of the terms of the Merger Agreement, see the section entitled “The Merger Agreement.” As discussed in the section entitled “The Merger—Recommendation of the NuStar Managing GP Board and Reasons for the Merger,” after careful consideration, the NuStar Managing GP Board unanimously (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of NuStar and its unitholders, (ii) approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger, (iii) approved the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended approval and adoption of the Merger Agreement by the NuStar Common Unitholders and (v) directed that the Merger Agreement be submitted to the NuStar Common Unitholders for approval and adoption.

Approval of the Merger Proposal is a condition to the Closing of the Merger. If the Merger Proposal is not approved, the Merger will not occur. For a detailed discussion of the terms and conditions of the Merger, see the section entitled “The Merger Agreement—Conditions to the Merger.”

Vote Required for Approval

Approval of the Merger Proposal requires the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units. A failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online), a broker non-vote or an abstention will have the same effect as a vote “AGAINST” the Merger Proposal.

Recommendation of the NuStar Managing GP Board

THE NUSTAR MANAGING GP BOARD UNANIMOUSLY RECOMMENDS THAT THE NUSTAR COMMON UNITHOLDERS VOTE “FOR” THE MERGER PROPOSAL.

45

PROPOSAL 2: THE COMPENSATION PROPOSAL

Pursuant to Section 14A of the Exchange Act and Rule 14a-21(c) thereunder, NuStar is requesting the NuStar Common Unitholders approve, by a non-binding, advisory vote, the compensation that may be received by NuStar Managing GP’s named executive officers in connection with the Merger as disclosed in the section entitled “The Merger—Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger” including the footnotes, tables and associated narrative discussion.

The NuStar Managing GP Board unanimously recommends that the NuStar Common Unitholders approve the following resolution:

“RESOLVED, that the compensation that may be paid or become payable to NuStar Managing GP’s named executive officers that is based on or otherwise relates to the Merger, as disclosed pursuant to Item 402(t) of Regulation S-K in the table in the section of the proxy statement/prospectus entitled “The Merger—Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger,” including the associated footnotes, tables and narrative discussion and the agreements and plans pursuant to which such compensation may be paid or become payable, are hereby APPROVED.”

Vote Required for Approval

The Compensation Proposal is a vote separate and apart from the vote to approve and adopt the Merger Agreement, and approval of the Compensation Proposal is not a condition to the completion of the Merger. Accordingly, you may vote to approve the Compensation Proposal and vote not to approve and adopt the Merger Agreement and vice versa. Because the vote is advisory in nature only, it will not be binding on either NuStar or Sunoco. Accordingly, to the extent that NuStar or Sunoco is contractually obligated to pay the compensation, the compensation will be payable to the named executive officers, subject only to the conditions applicable thereto, if the Merger Agreement is approved and adopted and the Merger completed, regardless of the outcome of the Compensation Proposal.

Approval of the Compensation Proposal requires the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting, assuming a quorum is present. Abstentions will have the same effect as a vote “AGAINST” the Compensation Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Compensation Proposal.

Recommendation of the NuStar Managing GP Board

THE NUSTAR MANAGING GP BOARD UNANIMOUSLY RECOMMENDS THAT THE NUSTAR COMMON UNITHOLDERS VOTE “FOR” THE COMPENSATION PROPOSAL.

46

PROPOSAL 3: THE ADJOURNMENT PROPOSAL

NuStar is requesting the NuStar Common Unitholders approve the adjournment of the NuStar Special Meeting, if necessary, to solicit additional proxies in favor of the Merger Proposal, if (i) there are holders of an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum at such meeting or (ii) there are insufficient votes at the time of such adjournment to approve the Merger Proposal.

If, at the NuStar Special Meeting, (i) the number of NuStar Common Units represented and voting in favor of the Merger Proposal is insufficient to approve such proposal or (ii) there are an insufficient number of NuStar Common Units present online or by proxy at the NuStar Special Meeting to constitute a quorum, NuStar may move to adjourn the NuStar Special Meeting in order to enable the NuStar Managing GP Board to solicit additional proxies to obtain a quorum or for approval of the Merger Proposal.

Vote Required for Approval

The Adjournment Proposal is a vote separate and apart from the vote to approve and adopt the Merger Agreement, and approval of the Adjournment Proposal is not a condition to the completion of the Merger. Accordingly, you may vote to approve the Adjournment Proposal and vote not to approve and adopt the Merger Agreement and vice versa.

Approval of the Adjournment Proposal requires the affirmative vote of the holders of at least a majority of the outstanding NuStar Common Units present online or by proxy at the NuStar Special Meeting. Abstentions have the same effect as a vote “AGAINST” the Adjournment Proposal. Broker non-votes and failure of any NuStar Common Unitholder to submit a vote (e.g., by not submitting a proxy or not voting online) will have no effect on the Adjournment Proposal.

NuStar does not intend to call a vote on the Adjournment Proposal if a quorum is present and the Merger Proposal is approved at the NuStar Special Meeting.

Recommendation of the NuStar Managing GP Board

THE NUSTAR MANAGING GP BOARD UNANIMOUSLY RECOMMENDS THAT THE NUSTAR COMMON UNITHOLDERS VOTE “FOR” THE ADJOURNMENT PROPOSAL.

47

THE MERGER

This section of the proxy statement/prospectus describes the material aspects of the Merger. This section may not contain all of the information that is important to you. You should carefully read this entire proxy statement/prospectus and the documents attached hereto and incorporated by reference into this proxy statement/prospectus, including the full text of the Merger Agreement, a copy of which is attached to this proxy statement/prospectus as Annex A, for a more complete understanding of the Merger and the transactions contemplated thereby. In addition, important business and financial information about each of Sunoco and NuStar is included in or incorporated by reference into this proxy statement/prospectus and is included in the annexes hereto. Please see the section entitled “Where You Can Find More Information.”

General

NuStar is seeking the approval and adoption by NuStar Common Unitholders of the Merger Agreement that NuStar entered into on January 22, 2024 with Sunoco, Merger Sub, NuStar GP, NuStar Managing GP and Sunoco GP and the transactions contemplated thereby, including the Merger. Under the terms of the Merger Agreement, Merger Sub will be merged with and into NuStar (the “Merger,” and the effective time of the merger, the “Effective Time”), with NuStar surviving the Merger as the Surviving Entity and a subsidiary of Sunoco.

Pursuant to the Merger Agreement and by virtue of the Merger, (i) each NuStar Common Unit issued and outstanding immediately prior to the Effective Time (other than any Excluded Units (as defined below) and Sunoco Held Units (as defined below)) will be converted into and will thereafter represent the right to receive 0.400 of a Sunoco Common Unit, and, if applicable, cash in lieu of fractional units (the “Merger Consideration,” such ratio, the “Exchange Ratio” and the issuance of such Sunoco Common Units in connection with the Merger, the “Unit Issuance”); (ii) each NuStar Preferred Unit issued and outstanding immediately prior to the Effective Time will remain issued and outstanding from and after the Effective Time as a limited partnership interest of the Surviving Entity in the Merger, having the same terms as are applicable to such NuStar Preferred Unit immediately prior to the Effective Time, (iii) the general partner interest in NuStar issued and outstanding immediately prior to the Effective Time will remain issued and outstanding from and after the Effective Time as the general partnership interest of the Surviving Entity in the Merger and (iv) all NuStar Common Units owned immediately prior to the Effective Time by NuStar, Sunoco or Merger Sub (collectively, the “Excluded Units”), and any NuStar Common Units owned, immediately prior to the Effective Time, by a subsidiary of Sunoco (“Sunoco Held Units”), will remain issued and outstanding from and after the Effective Time as limited partnership interests of the Surviving Entity in the Merger having the same terms as applicable to NuStar Common Units immediately prior to the Effective Time.

In addition, prior to the Effective Time, NuStar will declare and pay to the NuStar Common Unitholders the Special Distribution of $0.212 per NuStar Common Unit.

Background of the Merger

The terms of the Merger are the result of arm’s-length negotiations between NuStar and Sunoco. The following is a summary of the events leading up to the execution of the Merger Agreement and the key meetings, negotiations, discussions and actions between NuStar and Sunoco and their respective advisors that preceded the public announcement of the Merger. All dates in this section are in 2024 unless otherwise indicated.

The NuStar Managing GP Board and management regularly review and assess NuStar’s performance, strategy, financial position and leverage, opportunities and risks in light of current business and economic conditions, as well as developments in the midstream sector (and among master limited partnerships), and across a range of scenarios and potential future industry developments. These regular reviews have, at the direction of the NuStar Managing GP Board, included evaluation of a variety of potential strategic transactions as well as review of the current NuStar business plan and the considerations associated with maintaining the status quo and

48

continuing to execute on NuStar’s business plan. As part of these reviews, the NuStar Managing GP Board has considered NuStar’s position in an industry that is undergoing dramatic changes, and investor focus in the sector on increased size, diversification of assets, consistent return of capital and cheaper access to capital. As part of these reviews, the NuStar Managing GP Board has also received periodic updates from management and certain of its advisors regarding the general landscape of mergers and acquisitions, potential acquirers and merger candidates.

From time to time, senior executives of the NuStar Managing GP, including Brad Barron, the Chairman, President and Chief Executive Officer of NuStar Managing GP, have had informal and preliminary conversations about potential strategic combinations and acquisition opportunities in the sector with senior executives of other companies in the sector. Mr. Barron updated the NuStar Managing GP Board regarding these interactions during meetings of the NuStar Managing GP Board.

On September 25, 2023, Joseph Kim, the President and Chief Executive Officer of Sunoco GP, contacted Mr. Barron to let him know that he planned to send Mr. Barron a proposal for Sunoco to acquire all of the issued and outstanding NuStar Common Units in an all-equity transaction at an exchange ratio of 0.455 of a Sunoco Common Unit for each NuStar Common Unit (the “September Sunoco Proposal”). Mr. Barron indicated that he would review and evaluate the September Sunoco Proposal. Following the discussion, Mr. Kim sent a letter to Mr. Barron setting forth the September Sunoco Proposal. The letter indicated, among other things, that Sunoco expected to be able to execute definitive agreements and announce a transaction in approximately four to six weeks if NuStar was willing to engage.

Later that day, Mr. Barron informed Dan Hill, the presiding lead director of the NuStar Managing GP Board, Amy Perry, Executive Vice President – Strategic Development and General Counsel of NuStar Managing GP, Danny Oliver, Executive Vice President – Business Development and Engineering of NuStar Managing GP, and Tom Shoaf, Executive Vice President and Chief Financial Officer of NuStar Managing GP, of the receipt of the September Sunoco Proposal and Mr. Barron’s conversation with Mr. Kim. Mr. Barron and Mr. Hill agreed that the NuStar Managing GP Board would discuss the September Sunoco Proposal in executive session following the next regularly scheduled Board meeting on October 25, 2023.

On October 3, 2023, Mr. Kim called Mr. Barron, and Mr. Barron indicated that NuStar needed time to review the September Sunoco Proposal, and that he planned to discuss the proposal with the NuStar Managing GP Board at its next regularly scheduled meeting, currently scheduled for October 25, 2023. Mr. Barron indicated he expected he would be in a position to provide Mr. Kim with the NuStar Managing GP Board’s initial reaction regarding the September Sunoco Proposal in early November 2023.

On October 4, 2023, Mr. Kim sent Mr. Barron a document outlining potential benefits of a combination of Sunoco and NuStar on the terms set forth in the September Sunoco Proposal including, among other things, increased scale and diversification, industry dynamics, cost of capital of the combined entity and the financial profile of the combined entity.

Prior to October 25, 2023, Mr. Barron called each member of the NuStar Managing GP Board to describe the September Sunoco Proposal and his discussions with Mr. Kim, which would be discussed at the next Board meeting.

On October 25, 2023, the NuStar Managing GP Board held a meeting. By invitation of the NuStar Managing GP Board, Ms. Perry was present at the meeting. At the meeting, Mr. Barron updated the NuStar Managing GP Board on the September Sunoco Proposal and his discussions with Mr. Kim regarding the September Sunoco Proposal. Mr. Barron and Ms. Perry discussed management’s preliminary views on the considerations associated with pursuing the September Sunoco Proposal further or any other potential strategic alternatives, including continuing to maintain the status quo. After discussion, the NuStar Managing GP Board authorized management to (i) further consider the potential merits of the September Sunoco Proposal and engage

49

an outside financial advisor (with the terms of such engagement subject to final review and approval of the NuStar Managing GP Board) to assist the NuStar Managing GP Board and management in its review of the September Sunoco Proposal, and (ii) negotiate and enter into a non-disclosure agreement with Sunoco to enable the exchange of additional information in order to permit the NuStar Managing GP Board and management to further evaluate the September Sunoco Proposal. Members of the NuStar Managing GP Board also asked Mr. Barron about the contemplated governance for the combined partnership and instructed him to inquire further regarding the proposed composition of the Sunoco GP Board following closing. 

On November 1, 2023, Sunoco reported its third quarter 2023 earnings results.

On November 2, 2023, NuStar reported its third quarter 2023 earnings results, and later that day, Mr. Barron called Mr. Kim to inform him that the NuStar Managing GP Board had met to discuss the September Sunoco Proposal and had authorized management to further consider the potential merits of the September Sunoco Proposal and engage an outside financial advisor. Mr. Barron and Mr. Kim also discussed the possibility of member(s) of the NuStar Managing GP Board joining the Sunoco GP Board following the closing; Mr. Kim indicated that the composition of the post-closing Sunoco GP Board would need to be discussed with the Sunoco GP Board.

On November 10, 2023, NuStar and Sunoco executed a non-disclosure agreement containing, among other terms, standstill restrictions binding on Sunoco and its representatives for a period ending on the earlier of entry into a definitive agreement with respect to the proposed transaction and May 10, 2025, including a restriction on Sunoco’s ability to request that NuStar amend or waive the standstill restriction.

During the period from close of trading on September 25, 2023 (i.e., the date of the September Sunoco Proposal) through the close of trading on November 10, 2023, the trading price of Sunoco Common Units on the NYSE increased 12.27% and the trading price of NuStar Common Units on the NYSE decreased 4.02%.

On November 13, 2023, Mr. Kim, Scott Grischow, Senior Vice President, Finance and Treasurer of Sunoco GP, Karl Fails, Chief Operations Officer of Sunoco GP, Mr. Barron, Ms. Perry, Mr. Shoaf and Mr. Oliver held a meeting in San Antonio, Texas to discuss financial due diligence matters with respect to each of the NuStar and Sunoco businesses and the potential transaction. At the end of the meeting, Mr. Kim indicated that due to the relative performance of the prices of Sunoco Common Units and NuStar Common Units since the September Sunoco Proposal, the exchange ratio set forth in the September Sunoco Proposal was no longer being proposed by Sunoco.

Following the meeting, later in the day on November 13, 2023, Mr. Kim called Mr. Barron to discuss the exchange ratio in the proposed transaction, and indicated that he believed the premium implied by the exchange ratio in the September Sunoco Proposal was too high based on the relative performance of the prices of Sunoco Common Units and NuStar Common Units since the September Sunoco Proposal. Mr. Barron indicated that, based on his conversations with the NuStar Managing GP Board, the premium implied by the agreed-upon exchange ratio would need to be substantial in order for NuStar to be willing to transact. After discussion, Mr. Kim and Mr. Barron agreed that the two parties would continue to explore the merits of a potential merger transaction, and would negotiate a potential exchange ratio at a later time.

Following the November 13, 2023 discussions, Mr. Barron called each member of the NuStar Managing GP Board and updated them regarding the status of discussions. Each director indicated to Mr. Barron his or her respective continued support for NuStar to continue to evaluate a potential merger transaction.

On November 16, 2023, Mr. Barron and Mr. Kim spoke to debrief regarding the November 13 meeting. During their discussion, Mr. Barron and Mr. Kim agreed to postpone any discussion on the composition of the Sunoco GP Board.

50

On November 20, 2023, Ms. Perry contacted representatives of Barclays to discuss the September Sunoco Proposal and the potential engagement of Barclays to assist in the review of a potential merger transaction with Sunoco.

On November 27, 2023, Ms. Perry informed Mr. Grischow that NuStar had contacted representatives of Barclays about potentially advising NuStar in connection with its review of a potential merger transaction with Sunoco.

On November 30, 2023, representatives of Truist, financial advisor to Sunoco, on behalf of Sunoco, sent representatives of Barclays, on behalf of NuStar, a list of financial due diligence requests.

Throughout the period between the NuStar Managing GP Board meeting on October 25, 2023 and December 14, 2023, Mr. Barron kept Mr. Hill apprised of the status of management’s review of a potential merger transaction and of discussions between representatives of NuStar and Sunoco.

On December 14, 2023, the NuStar Managing GP Board held a meeting. By invitation of the NuStar Managing GP Board, Ms. Perry, Jorge del Alamo, Senior Vice President—Chief Information Officer & Controller of NuStar Managing GP, and representatives of each of Barclays and Wachtell, Lipton, Rosen & Katz, counsel to NuStar (“Wachtell Lipton”), were present at the meeting. Mr. del Alamo began the meeting by reviewing with the NuStar Managing GP Board the NuStar unaudited prospective financial information. After discussion, the NuStar Managing GP Board approved the NuStar unaudited prospective financial information. Mr. Barron then provided an overview of developments with respect to a potential transaction with Sunoco since the October 25, 2023 meeting. Representatives of Wachtell Lipton provided an overview of the NuStar Managing GP Board’s duties, including in considering the September Sunoco Proposal. Representatives of Barclays reviewed with the NuStar Managing GP Board the current midstream market, NuStar’s current position in the market, a preliminary financial analysis of NuStar, strategic alternatives potentially available to NuStar (including continuing to maintain the status quo, continuing discussions with Sunoco, a sale of NuStar to another company or a sale of NuStar to a financial sponsor), a preliminary overview of Sunoco and potential options for NuStar’s response to the September Sunoco Proposal, including potential exchange ratios and the fact that Mr. Kim had indicated on November 13, 2023 that the exchange ratio included in the September Sunoco Proposal was no longer being offered by Sunoco. The NuStar Managing GP Board then discussed the September Sunoco Proposal, including the considerations associated with the September Sunoco Proposal (and potential exchange ratios in a transaction, noting there had been subsequent discussions with Sunoco regarding the exchange ratio after the September Sunoco Proposal) and of different strategies for further engaging with Sunoco, the considerations associated with pursuing a transaction with alternative parties and the considerations associated with maintaining the status quo. The NuStar Managing GP Board also discussed its view that, based upon their knowledge of the industry and the likely strategic and financial buyers of targets with similar characteristics as NuStar in the industry and discussion with representatives of Barclays and management, if NuStar were to pursue a merger transaction, Sunoco would be the most likely to pay the highest premium (net of taxes, if applicable) to NuStar Common Unitholders. After discussion, the NuStar Managing GP Board (i) authorized and instructed NuStar Managing GP’s senior management to continue to engage with Sunoco regarding a potential transaction and keep the NuStar Managing GP Board apprised on the status of discussions, (ii) approved the engagement of Barclays as NuStar’s financial advisor, subject to review and approval of the terms of the engagement and customary conflicts disclosures, and who were subsequently formally engaged through the execution of an engagement letter with NuStar on December 29, 2023 and (iii) formed a working group for efficiency purposes of the NuStar Managing GP Board comprised of Dan Bates, Mr. Hill and W. Grady Rosier (the “NuStar Board Working Group”) who Mr. Barron would keep apprised of, and from whom he would solicit input regarding, negotiation of the potential transaction with Sunoco in between meetings of the Board, in each case, subject to the approval of the full NuStar Managing GP Board.

On December 19, 2023, representatives of the senior management teams of each of Sunoco GP and the NuStar Managing GP, including Mr. Kim, Mr. Fails, Arnold Dodderer, General Counsel of Sunoco GP, Dylan

51

Bramhall, Group Chief Financial Officer for Energy Transfer GP and Sunoco GP, Mr. Grischow, Mr. Barron, Ms. Perry, Mr. Shoaf, Mr. Oliver and Mr. del Alamo held a meeting in Dallas, Texas to discuss business and financial due diligence matters with respect to each of the NuStar and Sunoco businesses and the potential transaction, including the NuStar unaudited prospective financial information and Sunoco management’s projections for the Sunoco business. Representatives of each of Truist and Barclays also attended this meeting.

On December 20, 2023, Mr. Barron called each member of the NuStar Board Working Group to update the group on the December 19, 2023 meeting with representatives of Sunoco.

On December 23, 2023, representatives of Weil, Gotshal & Manges LLP, counsel for Sunoco (“Weil”), sent an initial draft of the Merger Agreement to representatives of Wachtell Lipton, on behalf of NuStar, which, among other things, (i) provided that NuStar would not be permitted to terminate the Merger Agreement in order to accept a “superior proposal” unless the NuStar Common Unitholders had voted on and failed to approve the transaction (the “force the vote provision”), (ii) did not contain any commitments of Energy Transfer in connection with the transaction and (iii) contemplated the breakup fee that would be payable by NuStar under certain circumstances be equal to 4% of NuStar’s equity value implied by the transaction.

On December 29, 2023, NuStar entered into an engagement letter with Barclays. Prior to entering into the engagement letter, Barclays provided NuStar with customary relationship disclosures, which included disclosures with respect to Sunoco and NuStar.

On January 1, representatives of Sunoco were granted access to a virtual data room being maintained on behalf of NuStar.

On January 2, representatives of NuStar were granted access to a virtual data room being maintained on behalf of Sunoco.

On January 4, Mr. Kim sent a letter to Mr. Barron (the “January 4 Sunoco Proposal”) setting forth a revised non-binding indication of interest for Sunoco to acquire all of the issued and outstanding NuStar Common Units in an all-equity transaction at an exchange ratio of 0.400 of a Sunoco Common Unit for each NuStar Common Unit. The January 4 Sunoco Proposal indicated, among other things, that Sunoco was targeting an announcement of the transaction on January 16.

Following receipt of the January 4 Sunoco Proposal, on January 4, Mr. Barron informed the NuStar Board Working Group of the receipt of the January 4 Sunoco Proposal. After discussion, the NuStar Board Working Group indicated that, subject to the review and approval of the full NuStar Managing GP Board, it was supportive of Mr. Barron and NuStar Managing GP management proceeding with its review and negotiation of a potential merger transaction based on the January 4 Sunoco Proposal.

Also on January 4, representatives of Truist, on behalf of Sunoco, and of Barclays, on behalf of NuStar, exchanged written due diligence request lists.

Also on January 4, Ms. Perry, Mr. Grischow and other representatives of NuStar and Sunoco held a meeting to further discuss each management team’s respective financial projections. Representatives of each of Barclays and Truist also attended this meeting.

On January 5, Mr. Barron called each member of the NuStar Managing GP Board (other than the members of the NuStar Board Working Group) to update them on the January 4 Sunoco Proposal.

Also on January 5, Ms. Perry, Mr. Grischow and other representatives of NuStar and Sunoco held a meeting to further discuss each management team’s respective financial projections. Representatives of each of Barclays and Truist also attended this meeting.

52

On January 8, Mr. Kim called Mr. Barron and inquired about NuStar’s expected timing for responding to the January 4 Sunoco Proposal. Mr. Barron indicated that he would discuss the January 4 Sunoco Proposal with the NuStar Managing GP Board later that week. Mr. Kim and Mr. Barron also discussed potential synergies and employee matters. During their discussion, Mr. Kim informed Mr. Barron that Sunoco was nearing an agreement to sell convenience stores in West Texas, New Mexico and Oklahoma and an agreement to acquire liquid fuels terminals in Amsterdam and Ireland.

On January 9, representatives of Wachtell Lipton, on behalf of NuStar, sent a revised draft of the Merger Agreement to representatives of Weil, on behalf of Sunoco, which, among other things, (i) rejected the proposed force the vote provision, (ii) included commitments of Energy Transfer in connection with the transactions (including negative covenants and commitments to cooperate with respect to regulatory matters) and (iii) contemplated the breakup fee that would be payable by NuStar under certain circumstances be equal to 2% of NuStar’s equity value implied by the transaction.

On January 10, Mr. Barron called Mr. Kim to discuss potential synergies and employee matters. During their discussion, Mr. Kim also provided Mr. Barron with an update on the status of the West Texas divestiture and the European liquid fuels terminals transaction.

On January 11, Sunoco issued a press release announcing that it had entered into an agreement to sell 204 convenience stores in West Texas, New Mexico and Oklahoma in the West Texas divestiture for approximately $1 billion and that it would acquire liquid fuels terminals in Amsterdam and Ireland.

Also on January 11, representatives of Truist, on behalf of Sunoco, and representatives of Barclays, on behalf of NuStar, discussed Sunoco’s contemplated financing plan in connection with the proposed transaction and potential financing terms Sunoco expected to obtain. Representatives of Barclays updated representatives of NuStar Managing GP management and Wachtell Lipton following the call.

Also on January 11, the NuStar Managing GP Board held a meeting. Ms. Perry and representatives of each of Barclays and Wachtell Lipton were present at the meeting. Prior to the meeting, Mr. Barron called each member of the NuStar Managing GP Board to provide the directors with an update on the status of management’s review of a potential merger transaction. Mr. Barron began the meeting by providing an overview of developments with respect to a potential merger transaction with Sunoco since the December 14, 2023 meeting, including the receipt of the January 4 Sunoco Proposal. Representatives of Barclays reviewed with the NuStar Managing GP Board the January 4 Sunoco Proposal, a preliminary financial analysis with respect to each of NuStar, Sunoco and the potential combination of NuStar and Sunoco and potential responses to the January 4 Sunoco Proposal. The participants of the meeting also discussed Sunoco’s announced West Texas divestiture and the European liquid fuels terminals transaction. In addition, during the discussion, representatives of Wachtell Lipton provided an overview of the status of negotiations of the Merger Agreement, including, among other things, the proposed force the vote provision. The NuStar Managing GP Board then discussed the January 4 Sunoco Proposal, including the considerations associated with the January 4 Sunoco Proposal and of different strategies for further engaging with Sunoco, the considerations associated with pursuing a transaction with alternative parties and the considerations associated with maintaining the status quo. The NuStar Managing GP Board also discussed its view that, based upon its knowledge of the industry and the likely strategic and financial buyers of targets with similar characteristics as NuStar in the industry and discussion with representatives of each of Barclays and management, if NuStar were to pursue a merger transaction, Sunoco would be the most likely to pay the highest premium (net of taxes, if applicable) to NuStar Common Unitholders. After discussion, the NuStar Managing GP Board authorized and instructed Mr. Barron to propose to Mr. Kim an increased exchange ratio of 0.410 of a Sunoco Common Unit for each NuStar Common Unit and the inclusion of a special distribution to be paid by NuStar prior to closing as part of the proposed merger consideration, which would be in an amount approximated to make NuStar Common Unitholders whole for one year of distribution dilution following closing of the merger (the “Special Distribution”). The NuStar Managing GP Board also approved the Sunoco unaudited prospective financial information, subject to adjustments to be made by NuStar Managing

53

GP’s management to take into account the West Texas divestiture and the European liquid fuels terminals transaction.

On January 12, Mr. Barron called Mr. Kim in order to reject the January 4 Sunoco Proposal and counter with an oral proposal (the “NuStar Counterproposal”) of an increased exchange ratio of 0.410 of a Sunoco Common Unit for each NuStar Common Unit and the inclusion of the Special Distribution. Mr. Barron also indicated that NuStar did not expect to be in position to announce a transaction prior to January 22, assuming Sunoco were to accept the NuStar Counterproposal. Mr. Kim indicated that he would discuss the NuStar Counterproposal with the Sunoco GP Board.

During the period from January 12 through the execution of the Merger Agreement, each of NuStar and Sunoco conducted additional due diligence on the other party through various calls and review of materials provided in the respective parties’ virtual data rooms and public filings.

On January 13, Mr. Kim called Mr. Barron to accept the proposed Special Distribution, in an amount of $0.212 per NuStar Common Unit, and to reject the proposed exchange ratio in the NuStar Counterproposal, instead proposing an exchange ratio of 0.400 of a Sunoco Common Unit for each NuStar Common Unit, consistent with the January 4 Sunoco Proposal. Mr. Barron indicated he would discuss Mr. Kim’s counterproposal (the “Sunoco Final Proposal”) with the NuStar Managing GP Board.

After their discussion, on January 13, Mr. Barron met with the NuStar Board Working Group to discuss the Sunoco Final Proposal. The NuStar Board Working Group indicated that, subject to the review and approval of the full NuStar Managing GP Board, it expected that the full NuStar Managing GP Board would likely be supportive of accepting the Sunoco Final Proposal.

After Mr. Barron met with the NuStar Board Working Group, he called Mr. Kim to discuss the Sunoco Final Proposal. Mr. Barron indicated that, subject to the ultimate approval of their respective boards of directors and the negotiation of definitive documentation, he believed the NuStar Managing GP Board would likely be supportive of a transaction on the terms outlined in the Sunoco Final Proposal. Mr. Kim indicated that he would discuss further with the Sunoco GP Board.

On January 13, representatives of Weil, on behalf of Sunoco, sent a revised draft of the Merger Agreement to representatives of Wachtell Lipton, on behalf of NuStar, which, among other things, (i) reinserted the force the vote provision, (ii) indicated Energy Transfer’s willingness to agree to make certain limited commitments in connection with the Merger to be set forth in a separate Support Agreement and (iii) contemplated the breakup fee that would be payable by NuStar under certain circumstances be equal to 3.5% of NuStar’s equity value implied by the transaction.

On January 15, representatives of Wachtell Lipton, on behalf of NuStar, and representatives of Weil, on behalf of Sunoco, had a call to negotiate open points in the Merger Agreement, including, among other things, the force the vote provision, potential commitments from Energy Transfer and the contemplated breakup fee.

On January 16, representatives of Truist, on behalf of Sunoco, and representatives of Barclays, on behalf of NuStar, discussed Sunoco’s contemplated financing plan in connection with the proposed transaction and potential financing terms Sunoco expected to obtain. Representatives of Barclays updated representatives of each of NuStar management and Wachtell Lipton following the call.

On January 17, representatives of Wachtell Lipton, on behalf of NuStar, sent a revised draft of the Merger Agreement to representatives of Weil, on behalf of Sunoco, which, among other things, (i) rejected the proposed force the vote provision, and (ii) contemplated the breakup fee that would be payable by NuStar under certain circumstances be equal to 3% of NuStar’s equity value implied by the transaction.

54

On January 18, representatives of Wachtell Lipton, on behalf of NuStar, sent an initial draft of NuStar’s disclosure schedules accompanying the Merger Agreement to representatives of Weil, on behalf of Sunoco.

On January 18, Mr. Kim called Mr. Barron and indicated that, subject to the ultimate approval of their respective boards of directors and the negotiation of definitive documentation, he believed the Sunoco GP Board would be supportive of a transaction on the terms outlined in the Sunoco Final Proposal. Mr. Kim indicated that the Sunoco GP Board was scheduled to meet on January 21 to consider approval of the transaction.

Beginning on January 18 through the execution of the Merger Agreement, Mr. Barron, Ms. Perry, Mr. Kim, Mr. Dodderer and representatives of each of Wachtell Lipton and Weil (and different subsets of that group) participated in calls to discuss and negotiate open points relating to employee matters in the Merger Agreement and related disclosure schedules, including, among other things employee severance and retention provisions.

On January 19, Mr. Barron, Mr. Kim and James Wright, Executive Vice President, General Counsel & Chief Compliance Officer of Energy Transfer GP, participated in several calls to discuss the proposed commitments to be made by Energy Transfer in connection with the Merger.

Also on January 19, representatives of Wachtell Lipton, on behalf of NuStar, sent representatives of Weil, on behalf of Sunoco, an initial draft of the Support Agreement.

Also on January 19, representatives of Weil, on behalf of Sunoco, sent representatives of Wachtell Lipton, on behalf of NuStar, a revised draft of the Merger Agreement, which, among other things, (i) accepted the deletion of the force the vote provision and (ii) accepted NuStar’s proposal that the breakup fee that would be payable by NuStar under certain circumstances be equal to 3% of NuStar’s equity value implied by the transaction.

On January 20, Mr. Kim and Mr. Wright discussed further the proposed commitments to be made by Energy Transfer in connection with the Merger.

Also on January 20, representatives of Weil, on behalf of Sunoco, sent an initial draft of Sunoco’s disclosure schedules accompanying the Merger Agreement to representatives of Wachtell Lipton, on behalf of NuStar.

On January 21, the NuStar Managing GP Board held a meeting. Ms. Perry and representatives of each of Barclays and Wachtell Lipton were present at the meeting. Mr. Barron began the meeting by providing an overview of developments with respect to a potential transaction with Sunoco since the January 12 meeting, including Sunoco’s response to the NuStar Counterproposal (i.e., the Sunoco Final Proposal). Representatives of Wachtell Lipton reminded the NuStar Managing GP Board of their duties, including with respect to the potential transaction with Sunoco, and provided an overview of the terms of the Merger Agreement, Support Agreement and the amendment to the NuStar Partnership Agreement. Representatives of Barclays reviewed its financial analyses of NuStar, Sunoco and the combined entity and delivered an oral opinion, subsequently confirmed by delivery of a written opinion, to the effect that, as of such date, and based upon and subject to the factors, procedures, assumptions, qualifications and limitations set forth in its opinion, the Merger Consideration and Special Distribution to be offered to NuStar Common Unitholders (other than holders of Excluded Units and Sunoco Held Units) in the Merger are fair, from a financial point of view, to such holders. After discussion, the NuStar Managing GP Board unanimously, on behalf of the NuStar Managing GP, in its own capacity and in its capacity as the general partner of the NuStar GP, and on behalf of the NuStar GP, (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of NuStar and its unitholders, (ii) approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger, (iii) approved the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended approval and adoption of the Merger Agreement by the NuStar Common Unitholders and (v) directed that the Merger Agreement be submitted to the NuStar Common Unitholders for approval and adoption.

55

Following the meeting of the NuStar Managing GP Board, through the morning of January 22, members of the respective management teams of the NuStar Managing GP, Sunoco GP and Energy Transfer GP and representatives of Wachtell Lipton and Weil finalized the Merger Agreement, related disclosure schedules, Support Agreement and all ancillary materials, including agreement that one mutually agreed member of the NuStar Managing GP Board would be added to the Sunoco GP Board at the Closing.

On the morning of January 22, NuStar and Sunoco issued a joint press release announcing the execution of the Merger Agreement.

Recommendation of the NuStar Managing GP Board and Reasons for the Merger

On January 21, 2024, the NuStar Managing GP Board unanimously, on behalf of the NuStar Managing GP, in its own capacity and in its capacity as the general partner of NuStar GP, and on behalf of NuStar GP, (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are in the best interests of NuStar and its unitholders, (ii) approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger, (iii) approved the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, (iv) recommended approval and adoption of the Merger Agreement by the NuStar Common Unitholders and (v) directed that the Merger Agreement be submitted to the NuStar Common Unitholders for approval and adoption. The NuStar Managing GP Board unanimously recommends that NuStar Common Unitholders vote “FOR” the Merger Proposal, “FOR” the Compensation Proposal and “FOR” the Adjournment Proposal.

In the course of reaching its determinations and recommendations, the NuStar Managing GP Board reviewed and discussed a significant amount of information and consulted with members of the NuStar Managing GP’s senior management and NuStar’s outside legal and financial advisors. The following are some of the significant factors that supported the NuStar Managing GP Board’s determination to approve the execution, delivery and performance of the Merger Agreement and recommend adoption and approval of the Merger Agreement by the NuStar Common Unitholders (which are presented below in no particular order and are not exhaustive):

The NuStar Managing GP Board’s belief that the expected business, assets, financial condition, results of operations, business plan and prospects of NuStar and Sunoco as combined businesses would be superior together than those of NuStar on a standalone basis.

56

Value and Composition of the Consideration.

57

Synergies and Strategic Considerations.

Opinion of Financial Advisor.

Due Diligence.

Likelihood of Completion of the Transaction.

58

Terms of the Merger Agreement.

The NuStar Managing GP Board also considered and balanced against the potentially positive factors with a number of uncertainties, risks and other countervailing factors in its deliberations concerning the Merger and the Merger Agreement, including the following (not necessarily presented in order of relative importance):

59

60

After taking into account the factors set forth above, as well as others, the NuStar Managing GP Board concluded that the risks, uncertainties, restrictions and potentially negative factors associated with the transaction were outweighed by the potential benefits of the transaction to NuStar Common Unitholders.

The foregoing discussion of factors considered by the NuStar Managing GP Board is not intended to be exhaustive but summarizes the material factors considered by the NuStar Managing GP Board. In light of the variety of factors considered in connection with their evaluation of the Merger Agreement and the Merger, the NuStar Managing GP Board did not find it practicable to, and did not, quantify, rank or otherwise assign relative weights to the specific factors considered in reaching their determinations and recommendations. Moreover, each member of the NuStar Managing GP Board applied his or her own personal business judgment to the process and may have given different weight to different factors. The NuStar Managing GP Board based its recommendation on the totality of the information presented, including thorough discussions with, and questioning of, the NuStar Managing GP’s senior management and outside legal and financial advisors.

In considering the recommendation of the NuStar Managing GP Board to approve and adopt the Merger Agreement, NuStar Common Unitholders should be aware that the executive officers and directors of the NuStar Managing GP have certain interests in the transaction that may be different from, or in addition to, the interests of NuStar Common Unitholders generally. See the section entitled “—Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger.”

It should be noted that this explanation of the reasoning of the NuStar Managing GP Board and certain information presented in this section is forward-looking in nature and should be read in light of the factors set forth in the section entitled “Cautionary Statement Regarding Forward-Looking Statements.”

61

Opinion of NuStar’s Financial Advisor

NuStar engaged Barclays to act as its financial advisor with respect to pursuing strategic alternatives for NuStar, including a possible sale of NuStar, pursuant to an engagement letter dated December 29, 2023. On January 21, 2024, Barclays rendered its oral opinion (which was subsequently confirmed in writing on January 22, 2024) to the NuStar Managing GP Board that, as of such date and based upon and subject to the qualifications, limitations and assumptions stated in its opinion, the Merger Consideration to be offered to NuStar Common Unitholders (other than holders of Excluded Units and Sunoco Held Units) in the Merger and the Special Distribution to be paid to NuStar Common Unitholders prior to the Effective Time is fair, from a financial point of view, to such holders.

The full text of Barclays’ written opinion, dated as of January 22, 2024, is attached as Annex C to this proxy statement/prospectus. Barclays’ written opinion sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations upon the review undertaken by Barclays in rendering its opinion. You are encouraged to read the opinion carefully in its entirety. The following is a summary of Barclays’ opinion and the methodology that Barclays used to render its opinion. This summary is qualified in its entirety by reference to the full text of the opinion.

Barclays’ opinion, the issuance of which was approved by Barclays’ Valuation and Fairness Opinion Committee, is addressed to the NuStar Managing GP Board, addresses only the fairness, from a financial point of view, of the Merger Consideration to be offered to NuStar Common Unitholders (other than holders of Excluded Units and Sunoco Held Units) in the Merger and the Special Distribution to be paid to NuStar Common Unitholders prior to the Effective Time and does not constitute a recommendation to any NuStar Common Unitholder as to how such NuStar Common Unitholder should vote with respect to the Merger or any other matter. The terms of the Merger were determined through arm’s-length negotiations between NuStar and Sunoco and were unanimously approved by the NuStar Managing GP Board. Barclays did not recommend any specific form of consideration to NuStar or that any specific form of consideration constituted the only appropriate consideration for the Merger. Barclays was not requested to address, and its opinion does not in any manner address, NuStar’s underlying business decision to proceed with or effect the Merger, the likelihood of the consummation of the Merger or the relative merits of the Merger as compared to any other transaction or business strategy in which NuStar may engage. In addition, Barclays expressed no opinion on, and its opinion does not in any manner address, (i) the fairness of the amount or the nature of (x) any compensation to any officers, directors or employees of any parties to the Merger, or any class of such persons, relative to the Merger Consideration to be offered to NuStar Common Unitholders (other than holders of Excluded Units and Sunoco Held Units) in the Merger and the Special Distribution to be paid to NuStar Common Unitholders prior to the Effective Time or (y) any portion or aspect of the Merger to any one class or group of NuStar’s or any other person’s equity security holders vis-à-vis any other class or group of NuStar’s or any other person’s security holders (including NuStar Preferred Unitholders, holders of the general partner interest in NuStar, holders of Excluded Units and holders of Sunoco Held Units and including the allocation of any consideration amongst or within such classes or groups of security holders), (ii) the fairness of any portion or aspect of the Merger to the holders of any class of securities, creditors or other consistencies of NuStar or any other person, or to any other person, other than the fairness, from a financial point of view, of the Merger Consideration to be offered to NuStar Common Unitholders (other than holders of Excluded Units and Sunoco Held Units) in the Merger and the Special Distribution to be paid to NuStar Common Unitholders prior to the Effective Time, (iii) the Subsidiary Transaction or (iv) the Redemptions. No limitations were imposed by the NuStar Managing GP Board upon Barclays with respect to the investigations made or procedures followed by it in rendering its opinion.

In arriving at its opinion, Barclays, among other things:

62

In arriving at its opinion, Barclays assumed and relied upon the accuracy and completeness of the financial and other information used by Barclays without any independent verification of such information (and had not assumed responsibility or liability for any independent verification of such information). Barclays also relied upon the assurances of management of NuStar Managing GP and Sunoco that they were not aware of any facts or circumstances that would make such information inaccurate or misleading. With respect to the NuStar unaudited prospective financial information, the Sunoco standalone projections and the Sunoco pro forma projections, upon the advice of NuStar, Barclays assumed that (i) such projections were reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of NuStar Managing GP as to the future financial performance of NuStar, Sunoco and the combined partnership, respectively, and (ii) NuStar, Sunoco and the combined partnership, respectively, will or would (as applicable) perform substantially in accordance with such projections. Furthermore, upon the advice of NuStar, Barclays assumed that the amounts and timing of

63

the Synergies Estimates were reasonable and that the Synergies Estimates would be realized in accordance with such estimates. In arriving at its opinion, Barclays assumed no responsibility for and expressed no view as to any such projections or estimates or the assumptions on which they were based. In arriving at its opinion, Barclays did not conduct a physical inspection of the properties and facilities of NuStar or Sunoco and did not make or obtain any evaluations or appraisals of the assets or liabilities of NuStar or Sunoco. In addition, Barclays was not authorized by NuStar to solicit, and did not solicit, any indications of interest from any third party with respect to the purchase of all or a part of NuStar’s business. Barclays’ opinion was necessarily based upon market, economic and other conditions as they existed on, and could be evaluated as of, January 22, 2024. Barclays assumed no responsibility for updating or revising its opinion based on events or circumstances that may have occurred after January 22, 2024. In addition, Barclays expressed no opinion as to the prices at which either the NuStar Common Units or Sunoco Common Units would trade following the announcement or consummation of the Merger. Barclays’ opinion should not be viewed as providing any assurance that market value of the Sunoco Common Units to be held by NuStar Common Unitholders after the consummation of the Merger will be in excess of the market value of NuStar Common Units owned by such NuStar Common Unitholders at any time prior to the announcement or consummation of the Merger.

Barclays assumed the accuracy of the representations and warranties contained in the Merger Agreement and all the agreements related thereto in all respects material to its analysis. Barclays also assumed, upon the advice of NuStar, that all material governmental, regulatory and third-party approvals, consents and releases for the Merger would be obtained within the constraints contemplated by the Merger Agreement and that the Merger will be consummated in accordance with the terms of the Merger Agreement without waiver, modification or amendment of any material term, condition or agreement thereof. Barclays did not express any opinion as to any tax or other consequences that might result from the Merger, nor did Barclays’ opinion address any legal, tax, regulatory or accounting matters, as to which Barclays understood NuStar had obtained such advice as it deemed necessary from qualified professionals.

In connection with rendering its opinion, Barclays performed certain financial, comparative and other analyses as summarized below. In arriving at its opinion, Barclays did not ascribe a specific range of values to the NuStar Common Units or the Sunoco Common Units but rather made its determination as to the fairness, from a financial point of view, to NuStar Common Unitholders of the Merger Consideration to be offered to such holders (other than holders of Excluded Units and Sunoco Held Units) in the Merger and the Special Distribution to be paid to such holders prior to the Effective Time on the basis of various financial and comparative analyses. The preparation of a fairness opinion is a complex process and involves various determinations as to the most appropriate and relevant methods of financial and comparative analyses and the application of those methods to the particular circumstances. Therefore, a fairness opinion is not readily susceptible to summary description.

In arriving at its opinion, Barclays did not attribute any particular weight to any single analysis or factor considered by it but rather made qualitative judgments as to the significance and relevance of each analysis and factor relative to all other analyses and factors performed and considered by it and in the context of the circumstances of the particular transaction. Accordingly, Barclays believes that its analyses must be considered as a whole, as considering any portion of such analyses and factors, without considering all analyses and factors as a whole, could create a misleading or incomplete view of the process underlying its opinion.

Summary of Material Financial Analyses

The following is a summary of the material financial analyses used by Barclays in preparing its opinion to the NuStar Managing GP Board.

Each of these methodologies was used to generate reference per unit equity value ranges for NuStar Common Units and reference per unit equity value ranges for Sunoco Common Units. The reference per unit equity value ranges were then also used to generate implied exchange ratios for each of these methodologies. For purposes of its analyses, Barclays looked at the Exchange Ratio of 0.400x of a Sunoco Common Unit for each

64

NuStar Common Unit in the Merger plus the $0.212 per NuStar Common Unit pursuant to the Special Distribution to determine an implied equity value of $24.00 per NuStar Common Unit for the Merger (the “Merger Unit Price”) based on the closing price of Sunoco Common Units at market close on January 19, 2024. For each of these methodologies, the implied equity value ranges for NuStar Common Units were compared to the Merger Unit Price and the implied exchange ratios were compared to the Exchange Ratio.

The summary of Barclays’ analyses and reviews provided below is not a complete description of the analyses and reviews underlying Barclays’ opinion. The preparation of a fairness opinion is a complex process involving various determinations as to the most appropriate and relevant methods of analysis and review and the application of those methods to particular circumstances, and, therefore, is not readily susceptible to summary description.

For the purposes of its analyses and reviews, Barclays made numerous assumptions with respect to industry performance, general business, economic, market and financial conditions and other matters, many of which are beyond the control of NuStar, Sunoco, Barclays or any other parties to the proposed transaction. No company, business or transaction considered in Barclays’ analyses and reviews is identical to NuStar, Sunoco, Merger Sub, NuStar GP, NuStar Managing GP, Sunoco GP or the Merger, and an evaluation of the results of those analyses and reviews is not entirely mathematical. Rather, the analyses and reviews involve complex considerations and judgments concerning financial and operating characteristics and other factors that could affect the acquisition, public trading or other values of the companies, businesses or transactions considered in Barclays’ analyses and reviews. None of NuStar, Sunoco, Merger Sub, NuStar GP, NuStar Managing GP, Sunoco GP, Barclays or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses and reviews and the ranges of valuations resulting from any particular analysis or review are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of companies, businesses or securities do not purport to be appraisals or reflect the prices at which the companies, businesses or securities may actually be sold. Accordingly, the estimates used in, and the results derived from, Barclays’ analyses and reviews are inherently subject to substantial uncertainty.

The summary of the financial analyses and reviews provided below includes information presented in tabular format. In order to fully understand the financial analyses and reviews used by Barclays, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses and reviews. Considering the data in the tables below without considering the full description of the analyses and reviews, including the methodologies and assumptions underlying the analyses and reviews, could create a misleading or incomplete view of Barclays’ analyses and reviews.

Throughout the summary of material financial analyses the term “EBITDA,” as used in connection with Barclays’ various financial analyses, means the relevant company’s estimated earnings before interest, taxes, depreciation and amortization and certain other noncash items.

Selected Comparable Company Analysis – NuStar

In order to assess how the public market values units of similar publicly traded companies and to provide a range of relative implied equity values per NuStar Common Unit by reference to those companies, which could then be used to calculate implied exchange ratio ranges, Barclays reviewed and compared specific financial and operating data relating to NuStar with selected companies that Barclays, based on its experience in the midstream industry, deemed comparable to NuStar.

The selected comparable companies with respect to NuStar were:

65

Barclays calculated and compared various financial multiples and ratios of NuStar and the selected comparable companies. As part of its selected comparable company analysis, Barclays calculated and analyzed each company’s enterprise value, or EV, as a multiple of its calendar year 2024 and 2025 estimated EBITDA. The EV of each company was obtained by adding its short- and long-term debt to the sum of the market value of its fully diluted equity value, the market value of the general partner equity value, if applicable, the value of any preferred stock (at liquidation value) and, if applicable, the book value of any minority interest, and subtracting its cash and cash equivalents. All of these calculations for the comparable companies (except in the case of Sunoco’s EV, which was based on or provided by, as applicable, the Sunoco standalone projections or NuStar Managing GP’s management) were performed and based on publicly available financial data (including FactSet, Bloomberg and Wall Street research) and closing prices, as of January 19, 2024, the last trading date prior to the delivery of Barclays’ opinion. The results of this selected comparable company analysis are summarized below:

Barclays selected the comparable companies listed above because their businesses and operating profiles are reasonably similar to that of NuStar. However, because no selected comparable company is exactly the same as NuStar, Barclays believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected comparable company analysis. Accordingly, Barclays also made qualitative judgments concerning differences between the business, financial and operating characteristics and prospects of NuStar and the selected comparable companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis. These qualitative judgments related primarily to the differing sizes, growth prospects, profitability levels and degree of operational risk between NuStar and the companies included in the selected company analysis. Based upon these judgments, Barclays selected (i) a range of 8.5x to 9.5x multiples of 2024 estimated EBITDA and applied such range to NuStar’s 2024 estimated EBITDA, as set out in the NuStar unaudited prospective financial information, and (ii) a range of 8.0x to 9.0x multiples of 2025 estimated EBITDA and applied such range to NuStar’s 2025 estimated EBITDA, as set out in the NuStar unaudited prospective financial information, to calculate a range of implied prices per NuStar Common Unit of $15.50 to $22.50.

Barclays noted that on the basis of the selected comparable company analysis, the Merger Unit Price of $24.00 per NuStar Common Unit was above the range of implied values per share calculated by Barclays’ selected comparable company analysis.

Selected Comparable Company Analysis – Sunoco

In order to assess how the public market values units of similar publicly traded companies and to provide a range of relative implied equity values per Sunoco Common Unit by reference to those companies, which could then be used to calculate implied exchange ratio ranges, Barclays reviewed and compared specific financial and operating data relating to Sunoco with selected companies that Barclays, based on its experience in the midstream industry, deemed comparable to Sunoco.

The selected comparable companies with respect to Sunoco were:

66

Barclays calculated and compared various financial multiples and ratios of Sunoco and the selected comparable companies. As part of its selected comparable company analysis, Barclays calculated and analyzed each company’s EV as a multiple of its calendar year 2024 EBITDA. The EV of each company was obtained by adding its short- and long-term debt to the sum of the market value of its fully diluted equity value, the market value of the general partner equity value, if applicable, the value of any preferred stock (at liquidation value) and, if applicable, the book value of any minority interest, and subtracting its cash and cash equivalents. All of these calculations, for the comparable companies (except in the case of NuStar’s EV, which was based on or provided by, as applicable, the NuStar unaudited prospective financial information or NuStar Managing GP’s management) were performed and based on publicly available financial data (including FactSet, Bloomberg and Wall Street research) and closing prices, as of January 19, 2024, the last trading date prior to the delivery of Barclays’ opinion. The results of this selected comparable company analysis are summarized below:

Barclays selected the comparable companies listed above because their businesses and operating profiles are reasonably similar to that of Sunoco. However, because no selected comparable company is exactly the same as Sunoco, Barclays believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected comparable company analysis. Accordingly, Barclays also made qualitative judgments concerning differences between the business, financial and operating characteristics and prospects of Sunoco and the selected comparable companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis. These qualitative judgments related primarily to the differing sizes, growth prospects, profitability levels and degree of operational risk between Sunoco and the companies included in the selected company analysis. Based upon these judgments, Barclays selected a range of 9.0x to 10.0x multiples of 2024 estimated EBITDA and applied such range to Sunoco’s 2024 estimated EBITDA as set out in the Sunoco standalone projections, to calculate a range of implied prices per Sunoco Common Unit of $51.25 to $62.00.

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of 0.250x to 0.439x Sunoco Common Units for each NuStar Common Unit. Barclays noted that the Exchange Ratio falls within the range of implied exchange ratios calculated by Barclays’ selected comparable company analysis.

67

Selected Precedent Transaction Analysis – NuStar

Barclays reviewed and compared the purchase prices and financial multiples paid in selected other transactions that Barclays, based on its experience with merger and acquisition transactions, deemed relevant. Barclays chose such transactions based on, among other things, the similarity of the applicable target companies in the transactions to NuStar with respect to the size, mix, margins and other characteristics of their businesses. The following tables set forth the transactions analyzed based on such characteristics:

Corporate Midstream Transactions

Logistics MLP Buy-Ins Transactions

As part of its selected precedent transactions analysis, for each of the selected transactions for which public information was available, Barclays calculated and analyzed the EV to estimated EBITDA for FY+1. The results of the selected precedent transactions analysis are summarized below:

Corporate Midstream Transactions

Logistics MLP Buy-Ins Transactions

The reasons for and the circumstances surrounding each of the selected precedent transactions analyzed were diverse and there are inherent differences in the business, operations, financial conditions and prospects of NuStar and the companies included in the selected precedent transaction analysis. Accordingly, Barclays believed that a purely quantitative selected precedent transaction analysis would not be particularly meaningful in the context of considering the proposed transaction. Barclays therefore made qualitative judgments concerning differences between the characteristics of the selected precedent transactions and the proposed transaction that

68

would affect the acquisition values of the selected target companies and NuStar. Based upon these judgments, Barclays selected a range of 8.5x to 10.0x multiples of FY+1 estimated EBITDA and applied such range to NuStar’s FY+1 estimated EBITDA, as set out in the NuStar unaudited prospective financial information, to calculate a range of implied prices per NuStar Common Unit of $17.00 to $25.25.

Barclays noted that on the basis of the selected precedent transaction analysis, the Merger Unit Price of $24.00 per NuStar Common Unit was within the range of implied values per share calculated by the selected precedents transaction analysis.

Selected Precedent Transaction Analysis – Sunoco

Barclays reviewed and compared the purchase prices and financial multiples paid in selected other transactions that Barclays, based on its experience with merger and acquisition transactions, deemed relevant. Barclays chose such transactions based on, among other things, the similarity of the applicable target companies in the transactions to Sunoco with respect to the size, mix, margins and other characteristics of their businesses. The following table sets forth the transactions analyzed based on such characteristics:

Corporate Midstream Transactions

As part of its selected precedent transactions analysis, for each of the selected transactions for which public information was available, Barclays calculated and analyzed the EV to estimated EBITDA for FY+1. The results of the selected precedent transactions analysis are summarized below:

Corporate Midstream Transactions

The reasons for and the circumstances surrounding each of the selected precedent transactions analyzed were diverse and there are inherent differences in the business, operations, financial conditions and prospects of Sunoco and the companies included in the selected precedent transaction analysis. Accordingly, Barclays believed that a purely quantitative selected precedent transaction analysis would not be particularly meaningful in the context of considering the proposed transaction. Barclays therefore made qualitative judgments concerning differences between the characteristics of the selected precedent transactions and the proposed transaction that would affect the acquisition values of the selected target companies and Sunoco. Based upon these judgments, Barclays selected a range of 9.5x to 11.0x multiples of FY+1 estimated EBITDA and applied such range to Sunoco’s FY+1 estimated EBITDA as set out in the Sunoco standalone projections to calculate a range of implied prices per Sunoco Common Unit of $56.75 to $73.00.

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of 0.233x to 0.445x Sunoco Common Units for each NuStar Common

69

Unit. Barclays noted that the Exchange Ratio falls within the range of implied exchange ratios calculated by Barclays’ selected precedent transactions analysis.

Discounted Cash Flow Analysis – NuStar

In order to estimate the present value of NuStar Common Units, Barclays performed a discounted cash flow analysis of NuStar. A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset by calculating the “present value” of estimated future cash flows of the asset. “Present value” refers to the current value of future cash flows or amounts and is obtained by discounting those future cash flows or amounts by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

To calculate the estimated EV of NuStar using the discounted cash flow method, Barclays added (i) NuStar’s projected after-tax unlevered free cash flows for calendar years 2024 through 2028 based on the NuStar unaudited prospective financial information to (ii) the “terminal value” of NuStar as of December 31, 2028, and discounted such amount to its present value using a range of selected discount rates. The after-tax unlevered free cash flows were calculated by adding to distributable cash flow preferred distributions and interest expense and subtracting growth capital expenditures and adjusting for certain other noncash items. The residual value of NuStar at the end of the forecast period, or “terminal value,” was estimated by selecting a range of terminal value multiples based on EBITDA for the period ending December 31, 2028 of 7.0x to 9.0x, which was derived by analyzing the results from the selected comparable company analysis and precedent transaction analysis and applying such range to NuStar’s 2028 estimated EBITDA, as set out in the NuStar unaudited prospective financial information. The range of after-tax discount rates of 8.5% to 10.0% was selected based on an analysis of the weighted average cost of capital of NuStar and the comparable companies. Barclays then calculated a range of implied prices per NuStar Common Unit by subtracting estimated net debt and preferred equity, each as of December 31, 2023, from the estimated EV using the discounted cash flow method and dividing such amount by the fully diluted number of NuStar Common Units. This analysis implied a range of prices per NuStar Common Unit of $19.00 to $27.75.

Barclays noted that on the basis of the discounted distributable cash flow analysis, the Merger Unit Price of $24.00 per NuStar Common Unit was within the range of implied values per share calculated by the discounted distributable cash flow analysis.

Discounted Cash Flow Analysis – Sunoco

In order to estimate the present value of Sunoco Common Units, Barclays performed a discounted cash flow analysis of Sunoco.

To calculate the estimated EV of Sunoco using the discounted cash flow method, Barclays added (i) Sunoco’s projected after-tax unlevered free cash flows for calendar years 2024 through 2028 based on the Sunoco standalone projections to (ii) the terminal value of Sunoco as of December 31, 2028, and discounted such amount to its present value using a range of selected discount rates. The after-tax unlevered free cash flows were calculated by adding to distributable cash flow interest expense and subtracting growth capital expenditures. The terminal value was estimated by selecting a range of terminal value multiples based on EBITDA for the period ending December 31, 2028 of 8.5x to 9.5x, which was derived by analyzing the results from the selected comparable company analysis and precedent transaction analysis and applying such range to Sunoco’s 2028 estimated EBITDA, as set out in the Sunoco standalone projections. The range of after-tax discount rates of 8.0% to 9.0% was selected based on an analysis of the weighted average cost of capital of Sunoco and the comparable companies. Barclays then calculated a range of implied prices per Sunoco Common Unit by subtracting estimated net debt, as of December 31, 2023, and the market value of the general partner equity value from the estimated EV using the discounted cash flow method and dividing such amount by the fully diluted number of units of Sunoco. This analysis implied a range of prices per Sunoco Common Unit of $53.25 to $65.50.

70

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of (i) 0.290x to 0.521x Sunoco Common Units for each NuStar Common Unit (excluding synergies) and (ii) 0.248x to 0.439x Sunoco Common Units for each NuStar Common Unit (with the implied reference equity value per unit range for Sunoco adjusted to include synergies based on the Synergies Estimates). Barclays noted that the Exchange Ratio falls within each range of the implied exchange ratios calculated by Barclays’ discounted distributable cash flow analysis.

Distribution Discount Analysis – NuStar

In order to estimate the present value of NuStar Common Units, Barclays performed a distribution discount analysis of NuStar. A distribution discount analysis is a valuation methodology used to derive a valuation of an entity by calculating the “present value” of estimated distributions of the entity. “Present value” refers to the current value of future distributions and is obtained by discounting those future distributions by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

To calculate the estimated present value of NuStar Common Units, Barclays added (i) the estimated distributions expected to be paid by NuStar Common Unitholders during the calendar years 2024 through 2028 based on the NuStar unaudited prospective financial information to (ii) the “terminal value” per NuStar Common Unit on December 31, 2028 and discounted such amount to its present value using a range of selected discount rates. The residual value of NuStar at the end of the forecast period, or “terminal value,” was calculated by dividing NuStar’s 2029 estimated distribution per unit by the difference of (i) the discount rate and (ii) the estimated long-term growth rate for NuStar distributions. In connection with this analysis, Barclays assumed (i) a coverage ratio range of 1.50x to NuStar’s status quo coverage ratio based on the NuStar unaudited prospective financial information, (ii) a range of discount rates of 10.5% to 11.5% that was selected based on an analysis of the cost of equity of NuStar and the comparable companies and (iii) a 0.0% long-term growth rate. Based upon these assumptions, Barclays calculated a range of implied prices per NuStar Common Unit of $14.25 to $26.50.

Barclays noted that on the basis of the distribution discount analysis, the Merger Unit Price was within the range of implied values per share calculated by the distribution discount analysis.

Distribution Discount Analysis – Sunoco

In order to estimate the present value of Sunoco Common Units, Barclays performed a distribution discount analysis of Sunoco.

To calculate the estimated present value of Sunoco Common Units, Barclays added (i) the estimated distributions expected to be paid by Sunoco to holders of Sunoco Common Units (net of general partner distributions through Sunoco’s incentive distribution rights waterfall) during the calendar years 2024 through 2028 based on the Sunoco standalone projections to (ii) the estimated “terminal value” per Sunoco Common Unit on December 31, 2028 and discounted such amount to its present value using a range of selected discount rates. The residual value of Sunoco at the end of the forecast period, or “terminal value,” was calculated by dividing Sunoco’s 2029 estimated distribution per unit by the difference of (i) the discount rate and (ii) the estimated long-term growth rate for Sunoco distributions. In connection with this analysis, Barclays assumed (i) a coverage ratio range of 1.25x to 1.75x, (ii) a range of discount rates of 9.5% to 10.5% that was selected based on an analysis of the cost of equity of Sunoco and the comparable companies and (iii) a 1.5% to 2.5% long-term growth rate. Based upon these assumptions, Barclays calculated a range of implied prices per Sunoco Common Unit of $43.00 to $61.00.

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of (i) 0.234x to 0.616x Sunoco Common Units for each NuStar Common Unit (excluding synergies) and (ii) 0.198x to 0.501x Sunoco Common Units for each NuStar Common Unit (with

71

the implied reference equity value per unit range for Sunoco adjusted to include synergies based on the Synergies Estimates). Barclays noted that the Exchange Ratio falls within each range of the implied exchange ratios calculated by Barclays’ distribution discount analysis.

Sponsor Acquisition Analysis

Barclays performed a sponsor acquisition analysis in order to ascertain a price for NuStar Common Units that might be achieved in a leveraged buyout transaction with a financial buyer using a debt capital structure consistent with the proposed transaction and based upon current market conditions. Barclays assumed the following in its analysis: (i) the existing capital structure, as of the date of Barclays’ opinion, will roll into the pro forma combined partnership, (ii) an equity investment that would achieve a rate of return of approximately 14.0% to 18.0% over five years and (iii) a projected EBITDA terminal value multiple of 7.0x to 9.0x for December 31, 2028. Based upon these assumptions, Barclays calculated a range of implied prices per NuStar Common Unit of $15.50 to $23.50.

Barclays noted that on the basis of the sponsor acquisition analysis, the Merger Unit Price was above the range of implied values per share calculated by the sponsor acquisition analysis.

Other Factors

Barclays also reviewed and considered other factors that were not considered part of its financial analyses in connection with rendering its advice, but were references for informational purposes, including, among other things, the Equity Research Price Targets Analysis, Historical Unit Price Analysis, Transaction Premium Analysis and Pro Forma Merger Consequences Analysis described below.

Equity Research Price Targets Analysis

Barclays reviewed publicly available one-year forward price targets for the NuStar Common Units prepared and published by equity research firms that covered NuStar as of January 19, 2024. The price targets published by the equity research firms did not necessarily reflect current market trading prices for the NuStar Common Units. Barclays noted that the range of low to high one-year forward unit price targets as of January 19, 2024 was $17.00 to $20.00.

Barclays reviewed publicly available one-year forward price targets for the Sunoco Common Units prepared and published by equity research firms that covered Sunoco as of January 19, 2024. The price targets published by the equity research firms did not necessarily reflect current market trading prices for the Sunoco Common Units. Barclays noted that the range of low to high one-year forward unit price targets as of January 19, 2024 was $54.00 to $65.00.

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of 0.262x to 0.370x Sunoco Common Units for each NuStar Common Unit.

Historical Unit Price Analysis

To illustrate the trend in the historical trading prices of NuStar Common Units, Barclays considered historical data with regard to the trading prices of NuStar Common Units for the 52-week period from January 19, 2023 to January 19, 2024. Barclays noted that, during this period, the closing price of NuStar Common Units ranged from $14.41 to $19.32.

To illustrate the trend in the historical trading prices of Sunoco Common Units, Barclays considered historical data with regard to the trading prices of Sunoco Common Units for the 52-week period from January 19, 2023 to January 19, 2024. Barclays noted that, during this period, the closing price of Sunoco Common Units ranged from $40.81 to $63.96.

72

Using the implied reference equity value per unit ranges for each of NuStar and Sunoco, Barclays derived a reference implied exchange ratio range of 0.225x to 0.473x Sunoco Common Units for each NuStar Common Unit.

Transaction Premium Analysis

In order to assess the premium offered to the NuStar Common Unitholders in the Merger relative to the premiums offered to equity holders in other transactions, Barclays reviewed the premium paid in selected transactions in the midstream industry since January 1, 2018. For each transaction, Barclays calculated the premium per unit paid by the acquirer by comparing the announced transaction value per unit to the target company’s historical average unit price during the following periods: (i) one trading day prior to announcement, (ii) 30 calendar days prior to announcement and (iii) 60 calendar days prior to announcement. The results of this transaction premium analysis are summarized below:

The reasons for and the circumstances surrounding each of the transactions analyzed in the transaction premium analysis were diverse and there are inherent differences in the business, operations, financial conditions and prospects of NuStar and the companies included in the transaction premium analysis. Accordingly, Barclays believed that a purely quantitative transaction premium analysis would not be particularly meaningful in the context of considering the proposed transaction. Barclays therefore made qualitative judgments concerning the differences between the characteristics of the selected transactions and the proposed transaction that would affect the acquisition values of the target companies and NuStar. Based upon these judgments, Barclays selected a range of 5.0% to 30.0% to the closing price of NuStar Common Units on January 19, 2024 to calculate a range of implied prices per share of NuStar of $19.00 to $23.25.

Pro Forma Merger Consequences Analysis

Barclays reviewed and analyzed the pro forma impact of the Merger on projected distributable cash flow and distributions of the combined partnership for each of 2024 and 2025. Barclays performed this analysis based on the NuStar unaudited prospective financial information, Sunoco standalone projections and Sunoco pro forma projections. Barclays noted that the pro forma per unit distributable cash flow for the combined partnership would be accretive to Sunoco standalone in each of 2024 and 2025, respectively, and would be dilutive to NuStar standalone in each of 2024 and 2025, respectively. Barclays also noted that the pro forma distribution per unit for the combined partnership would be dilutive to NuStar standalone in each of 2024 and 2025.

General

Barclays is an internationally recognized investment banking firm and, as part of its investment banking activities, is regularly engaged in the valuation of businesses and their securities in connection with mergers and acquisitions, investments for passive and control purposes, negotiated underwritings, competitive bids, secondary distributions of listed and unlisted securities, private placements and valuations for estate, corporate and other purposes. The NuStar Managing GP Board selected Barclays because of its familiarity with NuStar and Sunoco and because of Barclays’ qualifications, reputation and experience in the valuation of businesses and securities in connection with mergers and acquisitions generally, as well as substantial experience in transactions comparable to the Merger.

Barclays is acting as financial advisor to NuStar in connection with the Merger. As compensation for its services in connection with the Merger, NuStar paid Barclays a fee of $4 million upon the delivery of Barclays’

73

opinion, which is referred to as the “Opinion Fee.” The Opinion Fee was not contingent upon the conclusion of Barclays’ opinion or the consummation of the Merger. Additional compensation of $37 million will be payable on completion of the Merger against which the amounts paid for the Opinion Fee will be credited. In addition, NuStar has agreed to reimburse Barclays for a portion of its reasonable out-of-pocket expenses incurred in connection with the Merger and to indemnify Barclays for certain liabilities that may arise out of its engagement by NuStar and the rendering of Barclays’ opinion. Barclays has performed various investment banking services for NuStar, Sunoco and/or their respective affiliates in the past, and expects to perform such services in the future, and has received, and expects to receive, customary fees for such services. Specifically, in the past two years, Barclays has performed the following investment banking and financial services: (i) for NuStar, (a) having acted as lead book-running manager on NuStar’s registered offering of NuStar Common Units in August 2023 and (b) having participated as a lender under NuStar’s existing credit facilities; and (ii) for Sunoco, (a) having acted as initial purchaser on Sunoco’s offering of senior notes in September 2023 and (b) having participated as joint lead arranger and joint bookrunner on Sunoco’s amendment to its credit facility in April 2022. During the period beginning January 1, 2022 through the date of rendering its opinion, the aggregate amount of fees that Barclays received from NuStar and Sunoco for the investment banking and financial services was approximately $2.8 million and less than $0.5 million, respectively. In addition, Barclays and its affiliates in the past have provided, currently are providing, or in the future may provide, investment banking services to Energy Transfer, and certain of its affiliates and have received or in the future may receive customary fees for rendering such services, including having acted or acting as arranger, bookrunner and/or lender for Energy Transfer and certain of its affiliates in connection with certain financing transactions.

Barclays and its affiliates engage in a wide range of businesses from investment and commercial banking, lending, asset management and other financial and non-financial services. In the ordinary course of its business, Barclays and affiliates may actively trade and effect transactions in the equity, debt and/or other securities (and any derivatives thereof) and financial instruments (including loans and other obligations) of NuStar, Sunoco, Energy Transfer and/or their respective affiliates for its own account and for the accounts of its customers and, accordingly, may at any time hold long or short positions and investments in such securities and financial instruments.

Interests of NuStar Managing GP’s Directors and Executive Officers in the Merger

In considering the recommendation of the NuStar Managing GP Board that NuStar Common Unitholders approve the Merger and vote in favor of the Merger Proposal and the Merger-related Compensation Proposal, NuStar Common Unitholders should be aware that the executive officers and directors of NuStar have certain interests in the Merger that are or may be different from, or in addition to, the interests of NuStar Common Unitholders generally. The NuStar Managing GP Board was aware of these interests and considered them, among other matters, in evaluating and approving the Merger Agreement, and in making its recommendation that NuStar Common Unitholders adopt the Merger Agreement.

These interests are described in more detail below. The Merger will be a “change of control” for purposes of the NuStar executive compensation plans and agreements described below.

For purposes of this disclosure, the named executive officers of NuStar are Bradley C. Barron, President and Chief Executive Officer, Thomas R. Shoaf, Executive Vice President and Chief Financial Officer, Mary Rose Brown, Executive Vice President and Chief Administrative Officer, Amy L. Perry, Executive Vice President—Strategic Development and General Counsel, and Daniel S. Oliver, Executive Vice President—Business Development and Engineering. NuStar’s executive officer who is not a named executive officer for purposes of the discussion below is Jorge A. del Alamo, Senior Vice President—Chief Information Officer and Controller.

74

Certain Assumptions

Except as otherwise specifically noted, for purposes of quantifying the potential payments and benefits described in this section, the following assumptions were used:

The amounts indicated below are estimates based on multiple assumptions (including the assumptions described above) that may or may not actually occur or be accurate on the relevant date, and do not reflect certain compensation actions that may occur before completion of the Merger. Accordingly, the actual amounts received may differ materially from the estimates set forth below.

Treatment of NuStar Equity Awards

NuStar Restricted Unit Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Restricted Unit Award will become fully vested and will be cancelled and converted into the right to receive (i) a number of Sunoco Common Units equal to the product of (A) the number of NuStar Common Units subject to such NuStar Restricted Unit Award immediately prior to the Effective Time, multiplied by (B) the Exchange Ratio and (ii) a cash payment equal to the product of (A) the number of NuStar Common Units subject to such NuStar Restricted Unit Award immediately prior to the Effective Time multiplied by (B) the per-unit amount of the Special Distribution.

NuStar Performance Cash Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Performance Cash Award will become fully vested and will be cancelled and converted into the right to receive an amount in cash equal to 200% of the target amount of cash pursuant to such NuStar Performance Cash Award, except that for each NuStar Performance Cash Award that constitutes a carry forward award, the cash amount will equal 100% of the target amount.

NuStar Time-Vesting Cash Awards. At the Effective Time, pursuant to the terms of the applicable NuStar LTIP and the terms of the Merger Agreement, each NuStar Time-Vesting Cash Award will become fully vested and will be cancelled and converted into the right to receive an amount in cash equal to 100% of the amount of cash subject to such NuStar Time-Vesting Cash Award.

See the section entitled “—Quantification of Payments and Benefits to NuStar’s Named Executive Officers” below for an estimate of the value of each NuStar named executive officer’s unvested NuStar equity awards. Based on the relevant assumptions described above under “—Certain Assumptions,” the estimated aggregate amounts that would become vested and payable at the Effective Time to NuStar’s executive officer who is not a named executive officer in respect of such officer’s unvested NuStar LTI Awards prior to the date of the Merger Agreement is as follows: unvested NuStar Restricted Stock Unit Awards (taking into account the Special Distribution)—$1,017,237; unvested NuStar Performance Cash Awards (including carry forward awards)—$244,616 (based on the payout percentage specified in the Merger Agreement); and unvested Time-Vesting Cash Awards—$177,450. Based on the relevant assumptions described above under “—Certain Assumptions,” the estimated collective value of unvested NuStar Restricted Stock Unit Awards (taking into account the Special Distribution) held by all nine non-employee directors of NuStar that would become vested and payable at the Effective Time is $2,964,720.

75

Change of Control Severance Agreements

NuStar has entered into Change of Control Severance Agreements with each of its executive officers (each, a “CIC Agreement”). Under these CIC Agreements, each NuStar executive officer will be eligible for severance benefits upon a termination of employment other than for “cause,” death, or disability or a resignation by the executive officer for “good reason,” (as such terms are defined in the CIC Agreements) in each case, on or within three years following a change of control of NuStar.

The severance payments and benefits under each CIC Agreement are as follows:

(i) the product of (a) the higher of (1) the executive’s highest bonus earned under the annual incentive bonus plan of NuStar for the last three full fiscal years prior to the date of the change of control (or for a lesser number of full fiscal years prior to the date of the change of control for which the executive was eligible to earn this bonus, and annualized in the case of any pro rata bonus earned for a partial fiscal year) and (2) the annual bonus paid or payable for the most recently completed fiscal year during the employment period under the CIC Agreement, if any (such higher amount, the “Highest Annual Bonus”), and (b) a fraction with a numerator equal to the number of days in the current fiscal year through the executive officer’s employment termination date and a denominator of 365;

(ii) an amount equal to the product of (a) three for Mr. Barron; two and one-half for Mr. Shoaf, Ms. Brown, Ms. Perry and Mr. Oliver; and two for Mr. del Alamo (in each case, the “Severance Multiple”) and (b) the sum of the executive officer’s (1) annual base salary and (2) Highest Annual Bonus;

(iii) the amount of the excess of (a) the actuarial equivalent of the executive’s benefit under NuStar’s or an affiliate’s qualified defined benefit retirement plan (the “Retirement Plan”) and any excess or supplemental retirement plan in which the executive participates (collectively, the “SERP”) that the executive would have received if the executive’s employment had continued for a number of years equal to the Severance Multiple, over (b) the actuarial equivalent of the Executive’s actual benefit (paid or payable), if any, under the Retirement Plan and the SERP as of the executive officer’s employment termination date;

(iv) the amount of the sum of NuStar’s or an affiliate’s (as applicable) matching or other contributions under the qualified defined contribution plans and any excess or supplemental defined contribution plans in which the executive officer participates that the executive officer would have received if the executive officer’s employment had continued for a number of years equal to the Severance Multiple;

(v) if the executive officer experiences a termination in anticipation of a change in control that results in forfeiture of outstanding unvested equity awards that would have otherwise vested had the executive remained continuously employed through the date of a change of control, an amount equal to the amount the executive officer would have been entitled to receive with respect to the vesting of these forfeited awards if the awards had remained outstanding and vested on the date of the change of control; and

(vi) for a number of years equal to the Severance Multiple after the executive officer’s employment termination date, continued benefits for the executive officer and the executive officer’s family at least equal to, and at the same cost to the executive officer and/or the executive officer’s family, as those that would have been provided if the executive officer’s employment had not been terminated or, if more favorable to the executive officer, as in effect generally at any time thereafter with respect to other peer executives of NuStar or an affiliate and their families.

Under the terms of the CIC Agreement, if any change in control related payment or benefit is determined to be subject to an excise tax under Section 4999 of the Code, the executive officer is entitled to receive an additional payment to make the executive officer whole for the incremental tax cost of the payment or benefit. However, if it is determined that the value of all payments to the executive officer does not exceed 110% of the

76

executive officer’s safe harbor amount for purposes of Section 280G of the Code, then the additional make-whole payment will not be made and instead the amount of the change in control payments and benefits payable to the executive officer will be reduced so that the excise tax does not apply.

Each executive officer’s receipt and/or retention of the payments and benefits under the CIC Agreement are contingent on the executive officer timely executing and not revoking a release of claims against NuStar. Each executive officer is also bound by a confidentiality covenant after termination of employment.

Quantification

See the section entitled “—Quantification of Payments and Benefits to NuStar’s Named Executive Officers” below for the estimated severance amounts for each named executive officer. Based on the assumptions described above under “—Certain Assumptions,” the estimated cash severance (including prorated bonus) that would be payable to the one executive officer who is not a named executive officer is $1,431,895 (of which $1,384,800 is the estimated cash severance amount and $47,095 is the estimated prorated bonus amount) and the estimated make-whole payment that would be payable to such individual is $0.

Prorated Annual Bonus for the Year of Closing

NuStar and Sunoco have agreed that on or about the Effective Time, Sunoco will pay to each individual who is employed by NuStar or a subsidiary immediately before the Effective Time (including each executive officer) a prorated bonus equal to the employee’s target annual cash compensation opportunity for the year in which the Effective Time occurs, prorated to reflect the portion of the year elapsed prior to the Effective Time. It is intended that this prorated bonus would be provided without duplication of any prorated bonus that is due as part of the severance benefits under a CIC Agreement for an executive officer who has a qualifying termination at or after the Effective Time and during the same year in which the Effective Time occurs.

Quantification of Payments and Benefits to NuStar’s Named Executive Officers

The information set forth below regarding the compensation of each of NuStar’s named executive officers that is based on or otherwise relates to the Merger is provided in accordance with Item 402(t) of Regulation S-K.

Except as otherwise specifically noted, the disclosure below uses the relevant assumptions described above under “—Certain Assumptions.”

The amounts indicated below are estimates based on multiple assumptions (including the assumptions described above) that may or may not actually occur or be accurate on the relevant date, and do not reflect certain compensation actions that may occur before completion of the Merger. Accordingly, the actual amounts received by our named executive officers may differ materially from the estimates set forth below.

77