UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (date of earliest event reported): August 1, 2018

ENERGY TRANSFER PARTNERS, L.P.

(Exact name of registrant as specified in its charter)

8111 Westchester Drive, Suite 600

Dallas, Texas 75225

(Address of principal executive office) (Zip Code)

(214) 981-0700

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company    ☐

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 13(a) of the Exchange Act.    ☐

On August 1, 2018, Energy Transfer Partners, L.P. (“ETP”) and Energy Transfer Equity, L.P. (“ETE”) issued a press release announcing their entry into a definitive merger agreement pursuant to which a wholly owned subsidiary of ETE will merge with and into ETP, with ETP continuing as the surviving entity and a subsidiary of ETE. Under the terms of the definitive merger agreement, holders of ETP common units (other than ETE and its subsidiaries) will receive 1.28 common units of ETE in exchange for each ETP common unit and ETE’s incentive distribution rights in ETP will be cancelled. The full text of the press release is included as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated into this Item 7.01 by reference.

ETP has posted to its corporate website an investor presentation related to the transactions contemplated by the merger agreement, which is included as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated into this Item 7.01 by reference.

In accordance with General Instruction B.2 of Form 8-K, the information set forth in this Item 7.01 and the attached Exhibit 99.1 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended.

To the extent required, the information included in Item 7.01 of this Form 8-K is incorporated into this Item 8.01.

Cautionary Statement Regarding Forward-Looking Statements

This report includes “forward-looking” statements. Forward-looking statements are identified as any statement that does not relate strictly to historical or current facts. Statements using words such as “anticipate,” “believe,” “intend,” “project,” “plan,” “expect,” “continue,” “estimate,” “goal,” “forecast,” “may” or similar expressions help identify forward-looking statements. ETE and ETP cannot give any assurance that expectations and projections about future events will prove to be correct. Forward-looking statements are subject to a variety of risks, uncertainties and assumptions. These risks and uncertainties include the risks that the proposed transaction may not be consummated or the benefits contemplated therefrom may not be realized. Additional risks include: the ability to obtain requisite regulatory and unitholder approval and the satisfaction of the other conditions to the consummation of the proposed transaction, the potential impact of the announcement or consummation of the proposed transaction on relationships, including with employees, suppliers, customers, competitors and credit rating agencies, and the ability to achieve revenue, DCF and EBITDA growth, and volatility in the price of oil, natural gas, and natural gas liquids. Actual results and outcomes may differ materially from those expressed in such forward-looking statements. These and other risks and uncertainties are discussed in more detail in filings made by ETE and ETP with the Securities and Exchange Commission (the “SEC”), which are available to the public. ETE and ETP undertake no obligation to update publicly or to revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Additional Information and Where to Find It

SECURITY HOLDERS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND THE REGISTRATION STATEMENT REGARDING THE TRANSACTION CAREFULLY WHEN IT BECOMES AVAILABLE. These documents (when they become available), and any other documents filed by ETE or ETP with the SEC, may be obtained free of charge at the SEC’s website, at www.sec.gov. In addition, investors and security holders will be able to obtain free copies of the registration statement and the proxy statement/prospectus by phone, e-mail or written request by contacting the investor relations department of ETE or ETP at: 8111 Westchester Drive, Dallas, TX 75225, Attention: Investor Relations, Email: InvestorRelations@energytransfer.com.

Participants in the Solicitation

ETE, ETP and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies in connection with the proposed merger. Information regarding the directors and executive officers of ETE is contained in ETE’s Form 10-K for the year ended December 31, 2017, which was filed with the SEC on February 23, 2018. Information regarding the directors and executive officers of ETP is contained in ETP’s Form 10-K for the year ended December 31, 2017, which was filed with the SEC on February 23, 2018. Additional information regarding the interests of participants in the solicitation of proxies in connection with the proposed merger will be included in the proxy statement/prospectus.

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(d) Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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