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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-222049

JOINT PROXY STATEMENT AND PROSPECTUS

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

January 25, 2018

To the Stockholders of Vistra Energy Corp. and the Stockholders of Dynegy Inc.:

The board of directors (the “Vistra Energy Board”) of Vistra Energy Corp. (“Vistra Energy”) and the board of directors (the “Dynegy Board”) of Dynegy Inc. (“Dynegy”) each has approved an Agreement and Plan of Merger, dated as of October 29, 2017 (the “Merger Agreement”), by and between Vistra Energy and Dynegy, pursuant to which Dynegy will, subject to certain regulatory approvals, stockholder approvals and other customary closing conditions, merge with and into Vistra Energy (the “Merger”), with Vistra Energy continuing as the surviving corporation. The combined company resulting from the Merger will retain the name “Vistra Energy Corp.” and will continue to trade on the New York Stock Exchange (the “NYSE”) under the symbol “VST”.

Pursuant to the terms and subject to the conditions set forth in the Merger Agreement, at the effective time of the Merger, each outstanding share of common stock, par value $0.01 per share, of Dynegy (the “Dynegy Common Stock”) (other than those owned by Vistra Energy or any wholly owned subsidiary of Vistra Energy, or held in treasury by Dynegy or owned by any wholly owned subsidiary of Dynegy, which will be automatically cancelled and cease to exist) will be converted into the right to receive 0.652 newly issued, fully paid and nonassessable shares of common stock, par value $0.01 per share, of Vistra Energy (the “Vistra Energy Common Stock”).

Vistra Energy and Dynegy will each hold a special meeting of its stockholders.

Vistra Energy’s special meeting will be held at 1601 Bryan Street, 11th Floor, Dallas, Texas 75201 on March 2, 2018, at 9:00 a.m., Central Time. At the Vistra Energy special meeting, the holders of Vistra Energy Common Stock will be asked (a) to consider and vote on a proposal to adopt the Merger Agreement (the “Merger Proposal”), (b) to consider and vote on a proposal to approve the issuance of Vistra Energy Common Stock to the Dynegy stockholders (the “Stock Issuance”) in connection with the Merger as contemplated by the Merger Agreement (the “Stock Issuance Proposal”) and (c) to consider and vote on a proposal to approve the adjournment of the Vistra Energy special meeting, if necessary or appropriate, for the purpose of soliciting additional votes for the approval of the Merger Proposal and the Stock Issuance Proposal (the “Vistra Energy Adjournment Proposal”). The Vistra Energy Board recommends that holders of Vistra Energy Common Stock vote “FOR” the Merger Proposal, “FOR” the Stock Issuance Proposal, and “FOR” the Vistra Energy Adjournment Proposal.

Dynegy’s special meeting will be held at the Chase Center, 601 Travis Street, Houston, Texas 77002 on March 2, 2018, at 10:00 a.m., Central Time. At the Dynegy special meeting, the holders of Dynegy Common Stock will be asked (i) to consider and vote on the Merger Proposal, (ii) to consider and vote in an advisory capacity on compensation payable to executive officers of Dynegy in connection with the Merger (the “Dynegy Compensation Proposal”) and (iii) to consider and vote on a proposal to approve the adjournment of the Dynegy special meeting, if necessary or appropriate, for the purpose of soliciting additional votes for the approval of the Merger Proposal (the “Dynegy Adjournment Proposal”). The Dynegy Board unanimously recommends that holders of Dynegy Common Stock vote “FOR” the Merger Proposal, “FOR” the Dynegy Compensation Proposal and “FOR” the Dynegy Adjournment Proposal.

This joint proxy statement and prospectus provides you with detailed information about the special meetings of Vistra Energy and Dynegy, the Merger Agreement, the Merger and the other transactions contemplated by the

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Merger Agreement, including the Stock Issuance. A copy of the Merger Agreement is included as Annex A to this joint proxy statement and prospectus. Vistra Energy and Dynegy encourage you to read this joint proxy statement and prospectus, the Merger Agreement and the other annexes to this joint proxy statement and prospectus carefully and in their entirety. In particular, you should carefully consider the discussion in the section of this joint proxy statement and prospectus entitled “Risk Factors” beginning on page 35.

Your vote is very important, regardless of the number of shares you own. The Merger cannot be completed unless stockholders of both Vistra Energy and Dynegy approve certain proposals related to the Merger.

Whether or not you plan to attend the Vistra Energy special meeting or the Dynegy special meeting, as applicable, please submit a proxy to vote your shares as promptly as possible to make sure that your shares are represented at the Vistra Energy special meeting or Dynegy special meeting, as applicable. Please note that the failure to vote your Vistra Energy Common Stock or Dynegy Common Stock, as applicable, is the equivalent of a vote against the Merger Proposal.

Thank you in advance for your continued support.

Sincerely,

Curtis A. Morgan President and Chief Executive Officer Vistra Energy Corp.		Robert C. Flexon President and Chief Executive Officer Dynegy Inc.

Neither the U.S. Securities and Exchange Commission (the “SEC”) nor any state securities regulatory agency has approved or disapproved of the securities to be issued in connection with the Merger or passed upon the adequacy or accuracy of this joint proxy statement and prospectus. Any representation to the contrary is a criminal offense.

This joint proxy statement and prospectus is dated January 25, 2018, and is first being mailed to the stockholders of Vistra Energy and the stockholders of Dynegy on or about January 29, 2018.

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6555 Sierra Drive

Irving, Texas 75039

NOTICE OF SPECIAL MEETING TO VISTRA ENERGY STOCKHOLDERS

TO BE HELD ON MARCH 2, 2018

To the Stockholders of Vistra Energy:

A special meeting of stockholders of Vistra Energy Corp., a Delaware corporation (“Vistra Energy”), will be held at 1601 Bryan Street, 11th Floor, Dallas, Texas 75201 on March 2, 2018, starting at 9:00 a.m., Central Time, for the following purposes:

Vistra Energy will transact no other business at the Vistra Energy special meeting or any adjournment or postponement thereof. These items of business are described in the enclosed joint proxy statement and prospectus. The Vistra Energy board of directors (the “Vistra Energy Board”) has designated the close of business on January 19, 2018 as the record date for the purpose of determining the holders of shares of Vistra Energy’s common stock, par value $0.01 per share (the “Vistra Energy Common Stock”) who are entitled to receive notice of, and to vote at, the Vistra Energy special meeting and any adjournments or postponements of the special meeting, unless a new record date is fixed in connection with any adjournment or postponement of the special meeting. Only holders of record of Vistra Energy Common Stock at the close of business on the record date are entitled to notice of, and to vote at, the Vistra Energy special meeting and at any adjournment or postponement of the special meeting.

The Vistra Energy Board has (i) determined that it is in the best interest of Vistra Energy and the holders of Vistra Energy Common Stock to enter into the Merger Agreement, (ii) declared entry into the Merger Agreement to be advisable, (iii) authorized and approved Vistra Energy’s execution, delivery and performance of the Merger Agreement in accordance with its terms and Vistra Energy’s consummation of the transactions contemplated thereby, including the Merger and the Stock Issuance, (iv) directed that the adoption of the Merger Agreement and the approval of the Stock Issuance be submitted to a vote at a meeting of the holders of Vistra Energy Common Stock and (v) recommended that the holders of Vistra Energy Common Stock adopt the Merger Agreement and approve the Stock Issuance. The Vistra Energy Board recommends that holders of Vistra Energy Common Stock vote “FOR” the Merger Proposal, “FOR” the Stock Issuance Proposal and “FOR” the Vistra Energy Adjournment Proposal.

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Your vote is very important, regardless of the number of shares of Vistra Energy Common Stock you own. The Merger cannot be completed unless stockholders of both Vistra Energy and Dynegy approve certain proposals related to the Merger. Whether or not you plan to attend the Vistra Energy special meeting, please submit a proxy to vote your shares as promptly as possible to make sure that your shares are represented at the special meeting. Properly executed proxy cards with no instructions indicated on the proxy card will be voted “FOR” the Merger Proposal, “FOR” the Stock Issuance Proposal and “FOR” the Vistra Energy Adjournment Proposal. Even if you plan to attend the Vistra Energy special meeting in person, Vistra Energy requests that you complete, sign, date and return the enclosed proxy card in the accompanying envelope prior to the special meeting to ensure that your shares will be represented and voted at the special meeting if you are unable to attend.

You may also submit a proxy over the Internet using the Internet address on the enclosed proxy card or by telephone using the toll-free number on the enclosed proxy card. If you submit your proxy through the Internet or by telephone, you will be asked to provide the control number from the enclosed proxy card. If you are not a stockholder of record, but instead hold your shares in “street name” through a broker, bank, trust or other nominee, you must provide a proxy executed in your favor from your broker, bank, trust or other nominee in order to be able to vote in person at the special meeting.

If you do not vote on the Merger Proposal, it will have the same effect as a vote by you against the approval of the Merger Proposal.

If you attend the Vistra Energy special meeting, you may revoke your proxy and vote in person, even if you have previously returned your proxy card or submitted your proxy through the Internet or by telephone. If your Vistra Energy shares are held by a broker, bank, trust or other nominee, and you plan to attend the Vistra Energy special meeting, please bring to the special meeting your statement evidencing your beneficial ownership of your Vistra Energy shares. Please carefully review the instructions in the enclosed joint proxy statement and prospectus and the enclosed proxy card or the information forwarded by your broker, bank, trust or other nominee regarding each of these options.

January 25, 2018

Irving, Texas

By Order of the Vistra Energy Board

Cecily Small Gooch

Senior Vice President, Associate General Counsel, Chief Compliance Officer and Corporate Secretary

Vistra Energy Corp.

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601 Travis Street, Suite 1400

Houston, Texas 77002

NOTICE OF SPECIAL MEETING TO DYNEGY STOCKHOLDERS

TO BE HELD ON MARCH 2, 2018

To the Stockholders of Dynegy:

A special meeting of stockholders of Dynegy Inc., a Delaware corporation (“Dynegy”), will be held at the Chase Center, 601 Travis Street, Houston, Texas 77002 on March 2, 2018, starting at 10:00 a.m., Central Time, for the following purposes:

Dynegy will transact no other business at the Dynegy special meeting or any adjournment or postponement thereof. These items of business are described in the enclosed joint proxy statement and prospectus. The Dynegy board of directors (the “Dynegy Board”) has designated the close of business on January 19, 2018 as the record date for the purpose of determining the holders of shares of Dynegy’s common stock, par value $0.01 per share (the “Dynegy Common Stock”) who are entitled to receive notice of, and to vote at, the Dynegy special meeting and any adjournments or postponements of the special meeting, unless a new record date is fixed in connection with an adjournment or postponement of the special meeting. Only holders of record of Dynegy Common Stock at the close of business on the record date are entitled to notice of, and to vote at, the Dynegy special meeting and at any adjournment or postponement of the special meeting.

The Dynegy Board has unanimously (i) determined that it is in the best interest of Dynegy and holders of Dynegy Common Stock to enter into the Merger Agreement, (ii) declared entry into the Merger Agreement to be advisable, (iii) authorized and approved Dynegy’s execution, delivery and performance of the Merger Agreement in accordance with its terms and Dynegy’s consummation of the transactions contemplated thereby, including the Merger, (iv) directed that the adoption of the Merger Agreement be submitted to a vote at a meeting of the holders of Dynegy Common Stock and (v) recommended that the holders of Dynegy Common Stock adopt the Merger Agreement. The Dynegy Board unanimously recommends that holders of Dynegy Common Stock vote “FOR” the Merger Proposal, “FOR” the Dynegy Compensation Proposal and “FOR” the Dynegy Adjournment Proposal.

Your vote is very important, regardless of the number of shares of Dynegy Common Stock you own. The Merger cannot be completed unless stockholders of both Vistra Energy and Dynegy approve certain proposals related to the Merger. Whether or not you plan to attend the Dynegy special meeting, please submit a proxy to vote your shares as promptly as possible to make sure that your shares are represented

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at the special meeting. Properly executed proxy cards with no instructions indicated on the proxy card will be voted “FOR” the Merger Proposal, “FOR” the Dynegy Compensation Proposal and “FOR” the Dynegy Adjournment Proposal. Even if you plan to attend the Dynegy special meeting in person, Dynegy requests that you complete, sign, date and return the enclosed proxy card in the accompanying envelope prior to the special meeting to ensure that your shares will be represented and voted at the special meeting if you are unable to attend.

You may also submit a proxy over the Internet using the Internet address on the enclosed proxy card or by telephone using the toll-free number on the enclosed proxy card. If you submit your proxy through the Internet or by telephone, you will be asked to provide the control number from the enclosed proxy card. If you are not a stockholder of record, but instead hold your shares in “street name” through a broker, bank, trust or other nominee, you must provide a proxy executed in your favor from your broker, bank, trust or other nominee in order to be able to vote in person at the special meeting.

If you do not vote on the Merger Proposal, it will have the same effect as a vote by you against the approval of the Merger Proposal.

If you attend the Dynegy special meeting, you may revoke your proxy and vote in person, even if you have previously returned your proxy card or submitted your proxy through the Internet or by telephone. If your Dynegy shares are held by a broker, bank, trust or other nominee, and you plan to attend the Dynegy special meeting, please bring to the special meeting your statement evidencing your beneficial ownership of your Dynegy shares. Please carefully review the instructions in the enclosed joint proxy statement and prospectus and the enclosed proxy card or the information forwarded by your broker, bank, trust or other nominee regarding each of these options.

January 25, 2018

Houston, Texas

By Order of the Dynegy Board

Pat Wood III

Chairman of the Dynegy Board

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ADDITIONAL INFORMATION

This joint proxy statement and prospectus incorporates important business and financial information about Dynegy from other documents that are not included in or delivered with this joint proxy statement and prospectus. This information is available to you without charge upon your request. You can obtain the documents incorporated by reference into this joint proxy statement and prospectus by requesting them from Dynegy as follows:

MacKenzie Partners, Inc.

105 Madison Avenue

New York, NY 10016

Toll Free: (800) 322-2885

Email: proxy@mackenziepartners.com

or

601 Travis Street, Suite 1400

Houston, Texas 77002

Telephone: (713) 507-6466

Attention: Investor Relations

If you would like to request any of the Dynegy documents that are incorporated by reference into this joint proxy statement and prospectus, please do so by February 23, 2018 in order to receive them before the Vistra Energy special meeting and the Dynegy special meeting.

Investors may also consult Vistra Energy’s or Dynegy’s website for more information concerning the Merger and other related transactions described in this joint proxy statement and prospectus. Vistra Energy’s website is www.vistraenergy.com. Dynegy’s website is www.dynegy.com. Each company’s public filings are also available at www.sec.gov. The information contained on Vistra Energy’s and Dynegy’s websites is not part of this joint proxy statement and prospectus. The references to Vistra Energy’s and Dynegy’s websites are intended to be inactive textual references only.

For more information, see “Where You Can Find More Information and Incorporation by Reference” beginning on page 309.

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ABOUT THIS JOINT PROXY STATEMENT AND PROSPECTUS

This joint proxy statement and prospectus, which forms part of a registration statement on Form S-4 (Registration Statement No. 333-222049) filed by Vistra Energy with the SEC constitutes a prospectus of Vistra Energy for purposes of the Securities Act of 1933, as amended (the “Securities Act”), with respect to the offering and sale of Vistra Energy Common Stock to be issued to holders of Dynegy Common Stock pursuant to the Merger Agreement, as such agreement may be amended or modified from time to time. This joint proxy statement and prospectus also constitutes a proxy statement for Vistra Energy and Dynegy, respectively, for purposes of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and Delaware law. In addition, it constitutes a notice of special meeting to the Vistra Energy stockholders with respect to the Vistra Energy special meeting and a notice of special meeting to the Dynegy stockholders with respect to the Dynegy special meeting.

You should rely only on the information contained in or incorporated by reference into this joint proxy statement and prospectus. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this joint proxy statement and prospectus. This joint proxy statement and prospectus is dated January 25, 2018, and you should not assume that the information contained in, or incorporated by reference into, this joint proxy statement and prospectus is accurate as of any date other than that date (or, in the case of documents incorporated by reference, their respective dates). Neither the mailing of this joint proxy statement and prospectus to Vistra Energy’s stockholders or Dynegy’s stockholders nor the Stock Issuance pursuant to the Merger Agreement will create any implication to the contrary.

Certain industry and market data and other statistical information used throughout this joint proxy statement and prospectus are based on independent industry publications, government publications, reports by market research firms or other published independent sources, including certain data published by ERCOT, the PUCT and NYMEX. Neither Vistra Energy nor Dynegy commissioned any of these publications, reports or other sources.

Some Vistra Energy-related data is also based on good faith estimates, which are derived from Vistra Energy’s review of internal surveys, as well as the independent sources listed above. Industry publications, reports and other sources generally state that they have obtained information from sources believed to be reliable, but do not guarantee the accuracy and completeness of such information. While Vistra Energy and Dynegy believe that each of these publications, reports and other sources is reliable, neither party has independently investigated or verified the information contained or referred to therein or makes any representation as to the accuracy or completeness of such information. Forecasts are particularly likely to be inaccurate, especially over long periods of time, and what assumptions were used in preparing such forecasts are often unknown. Statements regarding industry and market data and other statistical information used throughout this joint proxy statement involve risks and uncertainties and are subject to change based on various factors, including those discussed under the headings “Cautionary Statement Regarding Forward-Looking Statements” and “Risk Factors.”

This joint proxy statement and 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 in which or to any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Information contained in this joint proxy statement and prospectus regarding Vistra Energy has been provided by Vistra Energy and information contained in this joint proxy statement and prospectus regarding Dynegy has been provided by Dynegy.

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DEFINED TERMS

Unless stated otherwise, when the following terms and abbreviations appear in the text of this joint proxy statement and prospectus, they have the meanings indicated below:

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QUESTIONS AND ANSWERS

The following questions and answers are intended to address briefly some commonly asked questions regarding the Merger Agreement, the Merger, the Stock Issuance and the other transactions contemplated by the Merger Agreement. Vistra Energy and Dynegy urge you to read carefully this entire joint proxy statement and prospectus, including the annexes and the other documents referred to or incorporated by reference into this joint proxy statement and prospectus, because the information in this section does not provide all of the information that might be important to you.

About the Merger

For Vistra Energy Stockholders

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Vistra Energy will transact no other business at the Vistra Energy special meeting or any adjournment or postponement thereof.

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For the Stock Issuance Proposal, you may vote “FOR,” “AGAINST” or “ABSTAIN.” For purposes of the Stock Issuance Proposal, provided a quorum is present, a failure to vote, or a failure to instruct your bank, broker, trust or other nominee to vote, will have no effect on the outcome of a vote on the Stock Issuance Proposal. Under the NYSE rules, an abstention from voting will be considered as a vote cast and, accordingly, will have the same effect as a vote “AGAINST” the Stock Issuance Proposal.

For the Vistra Energy Adjournment Proposal, you may vote “FOR,” “AGAINST” or “ABSTAIN.” For purposes of the Vistra Energy Adjournment Proposal, provided a quorum is present, a failure to vote, or a failure to instruct your bank, broker, trust or other nominee to vote, will have no effect on the outcome of a vote on the Vistra Energy Adjournment Proposal. An abstention from voting will have the same effect as a vote “AGAINST” the Vistra Energy Adjournment Proposal.

Properly executed proxy cards with no instructions indicated on the proxy card will be voted “FOR” the Merger Proposal, “FOR” the Stock Issuance Proposal and “FOR” the Vistra Energy Adjournment Proposal.

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To submit your proxy by telephone, dial the toll-free telephone number set forth on the enclosed proxy card using a touch tone phone and follow the recorded instructions. You will be asked to provide the control number from the enclosed proxy card.

To submit your proxy through the Internet, visit the website set forth on the enclosed proxy card. You will be asked to provide the control number from the enclosed proxy card.

Your proxy card will indicate the deadline for submitting proxies by telephone or through the Internet.

To submit your proxy by mail, complete, date and sign the enclosed proxy card and return it as promptly as practicable in the enclosed prepaid envelope. If you sign and return your proxy card, but do not mark the boxes showing how you wish to vote, your shares will be voted “FOR” the Merger Proposal, “FOR” the Stock Issuance Proposal and “FOR” the Vistra Energy Adjournment Proposal.

Stockholders of record will be able to vote in person at the Vistra Energy special meeting. If you intend to vote in person, please bring proper identification, together with proof that you are a record owner of shares. If you are not a stockholder of record, but instead hold your shares in “street name” through a broker, bank, trust or other nominee, you must provide a proxy executed in your favor from your broker, bank, trust or other nominee in order to be able to vote in person at the Vistra Energy special meeting. For more information, please read the question and answer referencing “street name” shares below.

Your attendance at the Vistra Energy special meeting does not automatically revoke your previously submitted proxy. If you have instructed your broker, bank, trust or other nominee to vote your shares, the options described above for revoking your proxy do not apply. Instead, you must follow the directions provided by your broker, bank, trust or other nominee to change your vote.

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For Dynegy Stockholders

Dynegy will transact no other business at the Dynegy special meeting or any adjournment or postponement thereof.

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For the Dynegy Compensation Proposal, you may vote “FOR,” “AGAINST” or “ABSTAIN.” For purposes of the Dynegy Compensation Proposal, provided a quorum is present, a failure to vote, or a failure to instruct your bank, broker, trust or other nominee to vote, will have no effect on the outcome of a vote on the Dynegy Compensation Proposal. An abstention from voting will have the same effect as a vote “AGAINST” the Dynegy Compensation Proposal.

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For the Dynegy Adjournment Proposal, you may vote “FOR,” “AGAINST” or “ABSTAIN.” For purposes of the Dynegy Adjournment Proposal, provided a quorum is present, a failure to vote, or a failure to instruct your bank, broker, trust or other nominee to vote, will have no effect on the outcome of a vote on the Dynegy Adjournment Proposal. An abstention from voting will have the same effect as a vote “AGAINST” the Dynegy Adjournment Proposal.

Properly executed proxy cards with no instructions indicated on the proxy card will be voted “FOR” the Merger Proposal, “FOR” the Dynegy Compensation Proposal and “FOR” the Dynegy Adjournment Proposal.

To submit your proxy by telephone, dial the toll-free telephone number set forth on the enclosed proxy card using a touch tone phone and follow the recorded instructions. You will be asked to provide the control number from the enclosed proxy card.

To submit your proxy through the Internet, visit the website set forth on the enclosed proxy card. You will be asked to provide the control number from the enclosed proxy card.

Your proxy card will indicate the deadline for submitting proxies by telephone or through the Internet.

To submit your proxy by mail, complete, date and sign the enclosed proxy card and return it as promptly as practicable in the enclosed prepaid envelope. If you sign and return your proxy card, but do not mark the boxes showing how you wish to vote, your shares will be voted “FOR” the Merger Proposal, “FOR” the Dynegy Compensation Proposal and “FOR” the Dynegy Adjournment Proposal.

Stockholders of record will be able to vote in person at the Dynegy special meeting. If you intend to vote in person, please bring proper identification, together with proof that you are a record owner of shares. If you are not a stockholder of record, but instead hold your shares in “street name” through a broker, bank, trust or other nominee, you must provide a proxy executed in your favor from your broker, bank, trust or other nominee in order to be able to vote in person at the Dynegy special meeting. For more information, please read the question and answer referencing “street name” shares below.

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Your attendance at the Dynegy special meeting does not automatically revoke your previously submitted proxy. If you have instructed your broker, bank, trust or other nominee to vote your shares, the options described above for revoking your proxy do not apply. Instead, you must follow the directions provided by your broker, bank, trust or other nominee to change your vote.

For Both Vistra Energy Stockholders and Dynegy Stockholders

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The particular consequences of the Merger to each Dynegy stockholder depend on such stockholder’s particular facts and circumstances. Dynegy stockholders should consult their tax advisors to understand fully the consequences to them of the Merger given their specific circumstances. For more information, see “Material U.S. Federal Income Tax Consequences” beginning on page 161.

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RISK FACTORS

In addition to other information included elsewhere in this joint proxy statement and prospectus and in the annexes to this joint proxy statement and prospectus, including the matters addressed in the section entitled “Cautionary Statement Regarding Forward-Looking Statements” beginning on page 61, you should carefully consider the following risk factors in deciding whether to vote for the proposals set forth in this joint proxy statement and prospectus. You should also read and consider the other information in this joint proxy statement and prospectus and the other documents incorporated by reference into this joint proxy statement and prospectus. Please also see “Where You Can Find More Information and Incorporation by Reference” on page 309.

Risks Related to the Merger

The Merger is subject to a number of conditions which, if not satisfied or waived in a timely manner, would delay the Merger or adversely impact the ability of Vistra Energy and Dynegy to complete the Merger on the terms set forth in the Merger Agreement or at all.

The completion of the Merger is subject to the satisfaction or waiver of a number of conditions. For example, before the Merger may be completed, both Vistra Energy stockholders and Dynegy stockholders must approve the Merger Proposal. In addition, various filings must be made with the FERC and certain other regulatory, antitrust and other authorities in the United States, including the PUCT, the NYPSC, the U.S. Department of Justice (“DOJ”) and the Federal Trade Commission (“FTC”). These governmental authorities may impose conditions on the completion, or require changes to the terms, of the Merger, including restrictions or conditions on the business, operations or financial performance of the combined company following completion of the Merger. These conditions or changes, including potential litigation brought in connection with the Merger, could have the effect of delaying completion of the Merger or imposing additional costs on or limiting the revenues of the combined company following the Merger, or could cause the combined company not to realize the anticipated benefits of the Merger, any of which could have a material adverse effect on the financial condition, results of operations and cash flows of the combined company and/or cause either Dynegy or Vistra Energy to abandon the Merger. These conditions or changes could also have the effect of causing the Merger to be consummated on terms different than those contemplated by the Merger Agreement or causing the Merger to fail to be consummated.

If Vistra Energy and Dynegy are unable to complete the Merger, they still will incur and will remain liable for significant transaction costs, including legal, accounting, filing, printing and other costs relating to the Merger. Also, depending upon the reasons for not completing the Merger, Vistra Energy may be required to pay Dynegy a termination fee of $100 million or reimburse its expenses up to $22 million, or Dynegy may be required to pay Vistra Energy a termination fee of $87 million or reimburse its expenses up to $22 million. For more information on the termination fees and/or expenses potentially payable by Vistra Energy and Dynegy, see “The Merger Agreement—Termination of the Merger Agreement.” If such a termination fee is payable, the payment of this fee could have a material adverse effect on the financial condition, results of operations and cash flows of Vistra Energy or Dynegy, as applicable.

Failure to consummate the Merger as currently contemplated or at all could adversely affect the price of Vistra Energy Common Stock or Dynegy Common Stock and the future business and financial results of Vistra Energy or Dynegy.

The completion of the Merger is subject to the satisfaction or waiver of a number of conditions. Vistra Energy and Dynegy cannot guarantee when or if these conditions will be satisfied or that the Merger will be successfully completed. If the Merger is not consummated, or is consummated on different terms than as contemplated by the Merger Agreement, Vistra Energy and Dynegy could be adversely affected and subject to a variety of risks associated with the failure to consummate the Merger, or to consummate the Merger as contemplated by the Merger Agreement, including:

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Any delay in the consummation of the Merger, any uncertainty about the consummation of the Merger on terms other than those contemplated by the Merger Agreement and any failure to consummate the Merger could adversely affect the business, financial results and stock price of Vistra Energy and/or Dynegy.

Vistra Energy and Dynegy will be subject to business uncertainties and contractual restrictions while the Merger is pending that could adversely affect their financial results.

Uncertainty about the effect of the Merger on employees, customers and suppliers may have an adverse effect on Vistra Energy’s and/or Dynegy’s business. These uncertainties may impair each company’s ability to attract, retain and motivate key personnel until the Merger is completed and for a period of time thereafter, and could cause customers, suppliers and others that deal with Vistra Energy and/or Dynegy to seek to change existing business relationships.

If, despite Vistra Energy’s and Dynegy’s retention and recruiting efforts, key employees depart or prospective employees fail to accept employment with them for any reason, including because of issues relating to the uncertainty and difficulty of integration or a desire not to remain with the combined company, the operations and financial results of Vistra Energy and/or Dynegy could be affected.

The pursuit of the Merger and the preparation for the integration of Dynegy into Vistra Energy may place a significant burden on management and internal resources. The diversion of management attention away from ongoing business concerns and any difficulties encountered in the transition and integration process could affect the business, and financial condition, results of operations and cash flows of Vistra Energy and/or Dynegy.

In addition, Vistra Energy and Dynegy are restricted under the Merger Agreement, without obtaining the other party’s consent, from taking certain other specified actions until the Merger occurs or the Merger Agreement terminates. These restrictions may prevent Vistra Energy and Dynegy from pursuing otherwise attractive business opportunities and making other changes to their businesses prior to completion of the Merger or termination of the Merger Agreement.

Because the market prices of shares of Vistra Energy Common Stock and shares of Dynegy Common Stock will fluctuate and the Exchange Ratio is fixed, the market value of the merger consideration at the date of the closing may vary significantly from the date the Merger Agreement was executed, the date of this joint proxy statement and prospectus and the dates of Vistra Energy’s special meeting and Dynegy’s special meeting.

Upon completion of the Merger, subject to certain exceptions, each outstanding share of Dynegy Common Stock will be converted into the right to receive 0.652 of a share of Vistra Energy Common Stock. The number of shares of Vistra Energy Common Stock to be issued pursuant to the Merger Agreement for each share of Dynegy Common Stock is fixed and will not change to reflect changes in the market price of Vistra Energy

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Common Stock or Dynegy Common Stock. Because the Exchange Ratio is fixed, the market value of the Vistra Energy Common Stock issued in connection with the Merger and/or the Dynegy Common Stock surrendered in connection with the Merger may be significantly higher or lower than the values of those shares on the date the Merger Agreement was signed, the date of this joint proxy statement and prospectus, the dates of Vistra Energy’s special meeting and Dynegy’s special meeting to consider the Merger Proposal or other earlier dates. Stock price changes may result from market assessment of the likelihood that the Merger will be completed, changes in the business, operations or prospects of Vistra Energy or Dynegy prior to or following the Merger, litigation or regulatory considerations, general business, market, industry or economic conditions and other factors both within and beyond the control of Vistra Energy and Dynegy. Neither Vistra Energy nor Dynegy is permitted to terminate the Merger Agreement because of changes in the market price of either company’s common stock.

The Merger Agreement contains provisions that limit the ability of Vistra Energy and Dynegy to pursue alternatives to the Merger, which could discourage a potential competing acquirer of Vistra Energy or Dynegy from making a favorable alternative transaction proposal and, in certain circumstances, could require Vistra Energy to pay a termination fee to Dynegy or Dynegy to a pay a termination fee to Vistra Energy.

Under the Merger Agreement, Vistra Energy and Dynegy are restricted from entering into alternative transactions to the Merger. Unless and until the Merger Agreement is terminated, subject to specified exceptions, Vistra Energy and Dynegy are restricted from soliciting, initiating, seeking or knowingly encouraging or facilitating, or engaging in any discussions or negotiations with any person regarding, any alternative proposal or any inquiry, proposal or indication of interest that would reasonably be expected to lead to an alternative proposal. While the Vistra Energy Board and the Dynegy Board are permitted to change their respective recommendations to stockholders prior to the applicable special meeting under certain circumstances, namely if one party to the Merger Agreement is in receipt of an unsolicited superior proposal or a certain unforeseeable, material intervening event has occurred, before that party’s board of directors changes its recommendation to stockholders in such circumstances, it must give the other party the opportunity to make a revised proposal. Vistra Energy and Dynegy may terminate the Merger Agreement and enter into an agreement with respect to an unsolicited superior proposal only if specified conditions have been satisfied, including compliance with the provisions of the Merger Agreement restricting solicitation of alternative proposals and requiring payment of a termination fee in certain circumstances. These provisions could discourage a third party that may have an interest in acquiring all or a significant part of Vistra Energy or Dynegy from considering or proposing such an acquisition, even if such third party were prepared to pay consideration with a higher per share cash or market value than the market value proposed to be received or realized in the Merger, or could result in a potential competing acquirer proposing to pay a lower price than it would otherwise have proposed to pay because of the added expense of the termination fee that may become payable in certain circumstances. As a result of these restrictions, Vistra Energy and Dynegy may not be able to enter into an agreement with respect to a more favorable alternative transaction without incurring potentially significant liabilities in respect of the Merger.

If the Merger Agreement is terminated because the Vistra Energy Board changes its recommendation to stockholders or Vistra Energy enters into a definitive agreement for an unsolicited superior proposal, Vistra Energy will be required to pay Dynegy a termination fee of $100 million. If the Merger Agreement is terminated because the Dynegy Board changes its recommendation to stockholders or Dynegy enters into a definitive agreement for an unsolicited superior proposal, Dynegy will be required to pay Vistra Energy a termination fee of $87 million. For more information on the termination fees and/or expenses potentially payable by Vistra Energy and Dynegy, see “The Merger Agreement—Termination of the Merger Agreement.” If such a termination fee is payable, the payment of this fee could have a material adverse effect on the financial condition, results of operations and cash flows of Vistra Energy or Dynegy, as applicable.

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Holders of Vistra Energy Common Stock and Dynegy Common Stock will have a reduced ownership and voting interest in the combined company after the Merger and will exercise less influence over management of the combined company.

Upon completion of the Merger, continuing holders of Vistra Energy Common Stock are expected to own 79% of the combined company’s fully diluted equity and former holders of Dynegy Common Stock are expected to own the remaining 21% of the combined company’s fully diluted equity. Stockholders of Vistra Energy and Dynegy currently have the right to vote for their respective boards of directors and on other matters affecting the applicable company. When the Merger occurs, each Dynegy stockholder will receive 0.652 shares of Vistra Energy Common Stock per share of Dynegy Common Stock, resulting in a percentage ownership of the combined company that is smaller than the Dynegy stockholders’ percentage ownership of Dynegy prior to the Merger. Correspondingly, each Vistra Energy stockholder will remain a stockholder in Vistra Energy with a percentage ownership of the combined company that is smaller than the stockholder’s percentage ownership of Vistra Energy prior to the Merger. As a result of these reduced ownership percentages, current stockholders of Vistra Energy and Dynegy may have less influence on the management and policies of the combined company than they now have with respect to Vistra Energy and Dynegy, respectively, on a standalone basis.

The Merger will result in changes to the board of directors that may affect the strategy and operations of the combined company.

In connection with the consummation of the Merger, the board of directors of the combined company will be expanded to consist of eleven members, which is expected to be comprised of all eight members of the Vistra Energy Board and three members from the Dynegy Board (provided such directors are willing to serve on the board of the combined company). This new composition of the board of directors may affect the combined company’s business strategy and operating decisions following the completion of the Merger.

If the Merger is not consummated by the End Date, Vistra Energy or Dynegy may terminate the Merger Agreement in certain circumstances.

Either Vistra Energy or Dynegy may terminate the Merger Agreement under certain circumstances, including, if the Merger has not been consummated by the End Date (which is April 29, 2019, unless extended pursuant to the terms of the Merger Agreement). However, this termination right will not be available to a party if that party failed to perform or comply in all material respects with its obligations under the Merger Agreement and that failure was the principal cause of the failure to consummate the Merger by such date.

An adverse judgment in any litigation challenging the Merger may prevent the Merger from becoming effective or from becoming effective within the expected timeframe.

It is possible that Vistra Energy stockholders or Dynegy stockholders may file lawsuits challenging the Merger or the other transactions contemplated by the Merger Agreement, which may name Vistra Energy, the Vistra Energy Board, Dynegy and/or the Dynegy Board as defendants. The outcome of such lawsuits cannot be assured, including the amount of costs associated with defending these claims or any other liabilities that may be incurred in connection with the litigation of these claims. If plaintiffs are successful in obtaining an injunction prohibiting the parties from completing the Merger on the agreed-upon terms, such an injunction may delay the consummation of the Merger in the expected timeframe, or may prevent the Merger from being consummated altogether. Whether or not any plaintiff’s claim is successful, this type of litigation may result in significant costs and divert management’s attention and resources, which could adversely affect the operation of Vistra Energy’s and Dynegy’s business.

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The unaudited pro forma condensed combined consolidated financial information included elsewhere in this joint proxy statement and prospectus are not intended to be representative of the combined company’s results after the Merger, and accordingly, you have limited financial information on which to evaluate the combined company following the Merger.

The unaudited pro forma condensed combined consolidated financial information included elsewhere in this joint proxy statement and prospectus has been presented for informational purposes only and is not intended to be indicative of the financial position or results of operations that actually would have occurred had the Merger been completed as of the dates indicated, nor is it indicative of the future operating results or financial position of the combined company following the Merger. The unaudited pro forma condensed combined consolidated financial information does not reflect future events that may occur after the Merger. The unaudited pro forma condensed combined consolidated financial information presented elsewhere in this joint proxy statement and prospectus is based in part on certain assumptions regarding the Merger that Vistra Energy and Dynegy believe are reasonable under the circumstances. Neither Vistra Energy nor Dynegy can assure you that the assumptions will prove to be accurate over time.

Following the Merger, the combined company may be unable to integrate Vistra Energy’s business and Dynegy’s business successfully and realize the anticipated synergies and other expected benefits of the Merger on the anticipated timeframe or at all.

The Merger involves the combination of two companies that currently operate as independent public companies. The combined company expects to benefit from certain cost savings and operating efficiencies, some of which will take time to realize. The combined company will be required to devote significant management attention and resources to the integration of Vistra Energy’s and Dynegy’s business practices and operations. The potential difficulties the combined company may encounter in the integration process include the following:

For all these reasons, you should be aware that it is possible that the integration process could result in the distraction of the combined company’s management, the disruption of the combined company’s ongoing business or inconsistencies in its operations, services, standards, controls, policies and procedures, any of which could adversely affect the combined company’s ability to maintain relationships with operators, vendors and employees, to achieve the anticipated benefits of the Merger, or could otherwise materially and adversely affect its business and financial results.

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The Merger will combine two companies that are currently affected by developments in the electric utility industry, including changes in regulation and increased competition. A failure to adapt to the changing regulatory environment after the Merger could adversely affect the stability of the combined company’s earnings and could result in the erosion of its market positions, revenues and profits.

Because Vistra Energy, Dynegy and their respective subsidiaries are regulated in the U.S. at the federal level and in several states, the two companies have been and will continue to be affected by legislative and regulatory developments. After the Merger, the combined company and/or its subsidiaries will be subject in the U.S. to extensive federal regulation as well as to state regulation in the states in which the combined company will operate. The costs and burdens associated with complying with these regulatory jurisdictions may have a material adverse effect on the combined company. Moreover, potential legislative changes, regulatory changes or otherwise may create greater risks to the stability of the combined company’s earnings generally. If the combined company is not responsive to these changes, it could suffer erosion in market position, revenues and profits as competitors gain access to its service territories.

Certain directors and executive officers of Vistra Energy and Dynegy have interests in the Merger that are different from, or in addition to, those of other Vistra Energy and Dynegy stockholders, which could have influenced their decisions to support or approve the Merger.

Vistra Energy and Dynegy stockholders should recognize that certain directors and executive officers of Vistra Energy and Dynegy have interests in the Merger that differ from, or that are in addition to, their interests as stockholders of Vistra Energy and Dynegy. These interests include, among others, continued service as a director or an executive officer of the combined company, the accelerated vesting of certain equity awards and/or severance benefits as a result of termination of employment in connection with the Merger. These interests, among others, may influence the directors and executive officers of Vistra Energy and/or Dynegy to approve and/or recommend Merger-related proposals. The Vistra Energy Board and the Dynegy Board were aware of and considered these interests at the time each approved the Merger Agreement. See “The Merger—Interests of Vistra Energy’s Directors and Executive Officers in the Merger” beginning on page 125 and “The Merger—Interests of Dynegy’s Directors and Executive Officers in the Merger” beginning on page 126.

The shares of Vistra Energy Common Stock to be received by Dynegy stockholders as a result of the Merger will have different rights from the shares of Dynegy Common Stock.

Upon completion of the Merger, Dynegy stockholders will become Vistra Energy stockholders and their rights as stockholders will be governed by Vistra Energy’s certificate of incorporation and bylaws. Certain of the rights associated with Vistra Energy Common Stock are different from the rights associated with Dynegy Common Stock. Please see “Comparison of Rights of Vistra Energy Stockholders and Dynegy Stockholders” beginning on page 288 for a discussion of the different rights associated with Vistra Energy Common Stock.

The combined company will have a significant amount of indebtedness. As a result, it may be more difficult for the combined company to pay or refinance its debts or take other actions, and the combined company may need to divert its cash flow from operations to debt service payments.

The combined company will have substantial indebtedness following completion of the Merger. In addition, subject to the limits contained in the documents governing such indebtedness, the combined company may be able to incur substantial additional debt from time to time to finance working capital, capital expenditures, investments or acquisitions, or for other purposes. If the combined company does so, the risks related to its high level of debt could intensify. The amount of such indebtedness could have material adverse consequences for the combined company, including:

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Moreover, to respond to competitive challenges, the combined company may be required to raise substantial additional capital to execute its business strategy. The combined company’s ability to arrange additional financing will depend on, among other factors, its financial position and performance, as well as prevailing market conditions and other factors beyond its control. Even if the combined company is able to obtain additional financing, its credit ratings could be adversely affected, which could raise its borrowing costs and limit its future access to capital and its ability to satisfy its obligations under its indebtedness.

The terms of the credit agreements governing the combined company’s two separate credit facilities will restrict its current and future operations, particularly the combined company’s ability to respond to changes or to take certain actions.

The combined company is expected to operate under two separate credit facilities, each with its own set of restrictive covenants. These restrictive covenants may limit the combined company’s ability to engage in acts that may be in the combined company’s long-term best interest, including restrictions on its ability to enter into intercompany business and financial transactions and arrangements, and therefore may prevent the combined company from fully realizing the potential benefits of the Merger. Additionally, the combined company’s ability to comply with the financial and other covenants contained in its debt instruments may be affected by changes in economic or business conditions or other events beyond its control.

A breach of the covenants and restrictions under the credit agreements governing the combined company’s credit facilities could result in an event of default under the applicable indebtedness. If the combined company experiences such a default, it may be required to take actions such as reducing or delaying capital expenditures, selling assets, restructuring or refinancing all or part of its existing debt, or seeking additional equity capital. The combined company may not be able to effect any such alternative measures, if necessary, on commercially reasonable terms or at all and, even if successful, those alternative actions may not allow the combined company to meet its scheduled debt service obligations. As a result of these restrictions, the combined company may be:

These restrictions may affect the combined company’s ability to grow in accordance with its strategy. In addition, the combined company’s financial results, its substantial indebtedness and credit ratings could adversely affect the availability and terms of its financing.

The combined company is expected to incur substantial expenses related to the Merger and the integration of Vistra Energy and Dynegy.

The combined company is expected to incur substantial expenses in connection with the Merger and the integration of Vistra Energy and Dynegy. There are a large number of processes, policies, procedures, operations, technologies and systems at each company that must be integrated, including purchasing, accounting and finance, sales, payroll, pricing, revenue management, commercial operations, risk management, marketing and employee benefits. While Vistra Energy and Dynegy have assumed that a certain level of expenses would be incurred, there are many factors beyond their control that could affect the total amount or the timing of the integration expenses.

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Moreover, many of the expenses that will be incurred are, by their nature, difficult to estimate accurately. These expenses could, particularly in the near term, exceed the savings that the combined company expects to achieve from the elimination of duplicative expenses and the realization of economies of scale and cost savings. These integration expenses likely will result in the combined company taking significant charges against earnings following the completion of the Merger, and the amount and timing of such charges are uncertain at present.

Risks Related to Vistra Energy

Vistra Energy’s revenues, results of operations and operating cash flows generally are negatively impacted by decreases in market prices for electricity.

Vistra Energy is not guaranteed any rate of return on capital investments in its businesses. Vistra Energy conducts integrated power generation and retail electricity activities, focusing on power generation, wholesale electricity sales and purchases, retail sales of electricity and services to end users and commodity risk management. Its wholesale and retail businesses are to some extent countercyclical in nature, particularly for the wholesale power and ancillary services supplied to the retail business. However, Vistra Energy does have a wholesale power position that exceeds the overall load requirements of its retail business and is subject to wholesale power price moves. As a result, Vistra Energy’s revenues, results of operations and operating cash flows depend in large part upon wholesale market prices for electricity, natural gas, uranium, lignite, coal, fuel and transportation in its regional market and other competitive markets and upon prevailing retail electricity rates, which may be impacted by, among other things, actions of regulatory authorities. Market prices may fluctuate substantially over relatively short periods of time. Demand for electricity can fluctuate dramatically, creating periods of substantial under- or over-supply. Over-supply can also occur as a result of the construction of new power plants, as Vistra Energy has observed in recent years. During periods of over-supply, electricity prices might be depressed. Also, at times there may be political pressure, or pressure from regulatory authorities with jurisdiction over wholesale and retail energy commodity and transportation rates, to impose price limitations, bidding rules and other mechanisms to address volatility and other issues in these markets.

Some of the fuel for Vistra Energy’s generation facilities is purchased under short-term contracts. Fuel costs (including diesel, natural gas, lignite, coal and nuclear fuel) may be volatile, and the wholesale price for electricity may not change at the same rate as changes in fuel costs. In addition, it purchases and sells natural gas and other energy related commodities, and volatility in these markets may affect costs incurred in meeting obligations.

Volatility in market prices for fuel and electricity may result from, among other factors:

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All of Vistra Energy’s generation facilities are currently located in the ERCOT market, a market with limited interconnections to other markets. The price of electricity in the ERCOT market is typically set by natural gas-fueled generation facilities, with wholesale electricity prices generally tracking increases or decreases in the price of natural gas. A substantial portion of its supply volumes in 2016 and the nine months ended September 30, 2017 were produced by its nuclear-, lignite- and coal-fueled generation assets. Natural gas prices have generally trended downward since mid- 2008 (from $11.12 per MMBtu in mid-2008 to $3.11 per MMBtu for the average settled price for the year ended December 31, 2017). Furthermore, in recent years, natural gas supply has outpaced demand primarily as a result of development and expansion of hydraulic fracturing in natural gas extraction, and the supply/demand imbalance has resulted in historically low natural gas prices. Because Vistra Energy’s baseload generating units and a substantial portion of its load following generating units are nuclear-, lignite- and coal-fueled, Vistra Energy’s results of operations and operating cash flows have been negatively impacted by the effect of low natural gas prices on wholesale electricity prices without a significant decrease in its operating cost inputs. Various industry experts expect this supply/demand imbalance to persist for a number of years, thereby depressing natural gas prices for a long-term period. As a result, the financial results from, and the value of, Vistra Energy’s generation assets could remain depressed or could materially decrease in the future unless natural gas prices rebound materially.

Wholesale electricity prices also track ERCOT market heat rates, which can be affected by a number of factors, including generation availability and the efficiency of the marginal supplier (generally natural gas-fueled generation facilities) in generating electricity. Vistra Energy’s market heat rate exposure is impacted by changes in the availability of generating resources, such as additions and retirements of generation facilities, and the mix of generation assets in ERCOT. For example, increasing renewable (wind and solar) generation capacity generally depresses market heat rates. Additionally, construction of more efficient generation capacity also depresses market heat rates. Decreases in market heat rates decrease the value of all of Vistra Energy’s generation assets because lower market heat rates generally result in lower wholesale electricity prices. Even though market heat rates have generally increased over the past several years, wholesale electricity prices have declined due to the greater effect of falling natural gas prices. As a result, the financial results from, and the value of, Vistra Energy’s nuclear-, lignite- and coal-fueled generation assets could significantly decrease in profitability and value and its financial condition and results of operations may be negatively impacted if ERCOT market heat rates decline.

Vistra Energy recently announced the retirement of its Big Brown, Sandow and Monticello units. A sustained decrease in the financial results from, or the value of, Vistra Energy’s generation units ultimately could result in the retirement or idling of certain other generation units. In recent years, Vistra Energy has operated certain of its lignite- and coal-fueled generation assets only during parts of the year that have higher electricity demand and, therefore, higher related wholesale electricity prices.

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Vistra Energy’s assets or positions cannot be fully hedged against changes in commodity prices and market heat rates, and hedging transactions may not work as planned or hedge counterparties may default on their obligations.

Vistra Energy’s hedging activities do not fully protect it against the risks associated with changes in commodity prices, most notably electricity and natural gas prices, because of the expected useful life of its generation assets and the size of its position relative to the duration of available markets for various hedging activities. Generally, commodity markets that Vistra Energy participate in to hedge its exposure to ERCOT electricity prices and heat rates have limited liquidity after two to three years. Further, Vistra Energy’s ability to hedge its revenues by utilizing cross-commodity hedging strategies with natural gas hedging instruments is generally limited to a duration of four to five years. To the extent Vistra Energy has unhedged positions, fluctuating commodity prices and/or market heat rates can materially impact its results of operations, cash flows, liquidity and financial condition, either favorably or unfavorably.

To manage its financial exposure related to commodity price fluctuations, Vistra Energy routinely enters into contracts to hedge portions of purchase and sale commitments, fuel requirements and inventories of natural gas, lignite, coal, diesel fuel, uranium and refined products, and other commodities, within established risk management guidelines. As part of this strategy, Vistra Energy routinely utilizes fixed-price forward physical purchase and sale contracts, futures, financial swaps and option contracts traded in over-the-counter markets or on exchanges. Although Vistra Energy devotes a considerable amount of time and effort to the establishment of risk management procedures, as well as the ongoing review of the implementation of these procedures, the procedures in place may not always function as planned and cannot eliminate all the risks associated with these activities. For example, Vistra Energy hedges the expected needs of its wholesale and retail customers, but unexpected changes due to weather, natural disasters, consumer behavior, market constraints or other factors could cause it to purchase electricity to meet unexpected demand in periods of high wholesale market prices or resell excess electricity into the wholesale market in periods of low prices. As a result of these and other factors, risk management decisions may have a material adverse effect on Vistra Energy.

Based on economic and other considerations, Vistra Energy may not be able to, or it may decide not to, hedge the entire exposure of its operations from commodity price risk. To the extent Vistra Energy does not hedge against commodity price risk and applicable commodity prices change in ways adverse to it, Vistra Energy could be materially and adversely affected. To the extent Vistra Energy does hedge against commodity price risk, those hedges may ultimately prove to be ineffective.

With the tightening of credit markets that began in 2008 and the expansion of regulatory oversight through various financial reforms, there has been a decline in the number of market participants in the wholesale energy commodities markets, resulting in less liquidity, particularly in the ERCOT electricity market. Notably, participation by financial institutions and other intermediaries (including investment banks) in such markets has declined. Extended declines in market liquidity could adversely affect Vistra Energy’s ability to hedge its financial exposure to desired levels.

To the extent Vistra Energy engages in hedging and risk management activities, it is exposed to the credit risk that counterparties that owe it money, energy or other commodities as a result of these activities will not perform their obligations to Vistra Energy. Should the counterparties to these arrangements fail to perform, Vistra Energy could be forced to enter into alternative hedging arrangements or honor the underlying commitment at then-current market prices. In such event, Vistra Energy could incur losses or forgo expected gains in addition to amounts, if any, already paid to the counterparties. ERCOT market participants are also exposed to risks that another ERCOT market participant may default on its obligations to pay ERCOT for electricity or services taken, in which case such costs, to the extent not offset by posted security and other protections available to ERCOT, may be allocated to various non-defaulting ERCOT market participants, including Vistra Energy.

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Vistra Energy’s results of operations and financial condition could be materially and adversely affected if energy market participants continue to construct additional generation facilities (i.e., new-build) in ERCOT despite relatively low power prices in ERCOT and such additional generation capacity results in a reduction in wholesale power prices.

Given the overall attractiveness of ERCOT and certain tax benefits associated with renewable energy, among other matters, energy market participants have continued to construct new generation facilities (i.e., new-build) in ERCOT despite relatively low wholesale power prices. If this market dynamic continues, Vistra Energy’s results of operations and financial condition could be materially and adversely affected if such additional generation capacity results in an over-supply of electricity in ERCOT that causes a reduction in wholesale power prices in ERCOT.

Vistra Energy’s liquidity needs could be difficult to satisfy, particularly during times of uncertainty in the financial markets or during times of significant fluctuation in commodity prices, and Vistra Energy may be unable to access capital on favorable terms or at all in the future, which could have a material adverse effect on Vistra Energy. Vistra Energy currently maintains non-investment grade credit ratings that could negatively affect its ability to access capital on favorable terms or result in higher collateral requirements, particularly if its credit ratings were to be downgraded in the future.

Vistra Energy’s businesses are capital intensive. In general, Vistra Energy relies on access to financial markets and credit facilities as a significant source of liquidity for its capital requirements and other obligations not satisfied by cash-on-hand or operating cash flows. The inability to raise capital or to access credit facilities, particularly on favorable terms, could adversely impact Vistra Energy’s liquidity and its ability to meet its obligations or sustain and grow its businesses and could increase capital costs and collateral requirements, any of which could have a material adverse effect on Vistra Energy.

Vistra Energy’s access to capital and the cost and other terms of acquiring capital are dependent upon, and could be adversely impacted by, various factors, including:

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In addition, Vistra Energy currently maintains non-investment grade credit ratings. As a result, Vistra Energy may not be able to access capital on terms (financial or otherwise) as favorable as companies that maintain investment grade credit ratings or Vistra Energy may be unable to access capital at all at times when the credit markets tighten. In addition, its non-investment grade credit ratings may result in counterparties requesting collateral support (including cash or letters of credit) in order to enter into transactions with Vistra Energy.

A downgrade in long-term debt ratings generally causes borrowing costs to increase and the potential pool of investors to shrink, and could trigger liquidity demands pursuant to contractual arrangements. Future transactions by Vistra Energy or any of its subsidiaries, including the issuance of additional debt, could result in a temporary or permanent downgrade in its credit ratings.

The Vistra Operations Credit Facilities impose restrictions on it and any failure to comply with these restrictions could have a material adverse effect on Vistra Energy.

The Vistra Operations Credit Facilities contain restrictions that could adversely affect Vistra Energy by limiting its ability to plan for, or react to, market conditions or to meet its capital needs and could result in an event of default under the Vistra Operations Credit Facilities. The Vistra Operations Credit Facilities contain events of default customary for financings of this type. If Vistra Energy fails to comply with the covenants in the Vistra Operations Credit Facilities and is unable to obtain a waiver or amendment, or a default exists and is continuing, the lenders under such agreements could give notice and declare outstanding borrowings thereunder immediately due and payable. Any such acceleration of outstanding borrowings could have a material adverse effect on Vistra Energy.

Certain of Vistra Energy’s obligations are required to be secured by letters of credit or cash, which increase its costs. If Vistra Energy is unable to provide such security, it may restrict its ability to conduct its business, which could have a material adverse effect on Vistra Energy.

Vistra Energy undertakes certain hedging and commodity activities and enters into certain financing arrangements with various counterparties that require cash collateral or the posting of letters of credit which are at risk of being drawn down in the event Vistra Energy defaults on its obligations. Vistra Energy currently uses margin deposits, prepayments and letters of credit as credit support for commodity procurement and risk management activities. Future cash collateral requirements may increase based on the extent of its involvement in standard contracts and movements in commodity prices, and also based on its credit ratings and the general perception of creditworthiness in the markets in which Vistra Energy operate. In the case of commodity arrangements, the amount of such credit support that must be provided typically is based on the difference between the price of the commodity in a given contract and the market price of the commodity. Significant movements in market prices can result in its being required to provide cash collateral and letters of credit in very large amounts. The effectiveness of Vistra Energy’s strategy may be dependent on the amount of collateral available to enter into or maintain these contracts, and liquidity requirements may be greater than it anticipates or will be able to meet. Without a sufficient amount of working capital to post as collateral, Vistra Energy may not be able to manage price volatility effectively or to implement its strategy. An increase in the amount of letters of credit or cash collateral required to be provided to its counterparties may have a material adverse effect on Vistra Energy.

Vistra Energy may not be able to complete future acquisitions or successfully integrate future acquisitions into its business, which could result in unanticipated expenses and losses.

As part of Vistra Energy’s growth strategy, it has pursued acquisitions and may continue to do so. Vistra Energy’s ability to continue to implement this component of its growth strategy will be limited by its ability to

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identify appropriate acquisition or joint venture candidates and its financial resources, including available cash and access to capital. Any expense incurred in completing acquisitions or entering into joint ventures, the time it takes to integrate an acquisition or Vistra Energy’s failure to integrate acquired businesses successfully could result in unanticipated expenses and losses. Furthermore, Vistra Energy may not be able to fully realize the anticipated benefits from any future acquisitions or joint ventures it may pursue. In addition, the process of integrating acquired operations into its existing operations may result in unforeseen operating difficulties and expenses and may require significant financial resources that would otherwise be available for the execution of its business strategy.

Vistra Energy may be responsible for U.S. federal and state income tax liabilities that relate to the PrefCo Preferred Stock Sale and Spin-Off.

Pursuant to the Tax Matters Agreement, the parties thereto have agreed to take certain actions and refrain from taking certain actions in order to preserve the intended tax treatment of the Spin-Off and to indemnify the other parties to the extent a breach of such covenant results in additional taxes to the other parties. If Vistra Energy breaches such a covenant (or, in certain circumstances, if its stockholders or creditors of its Predecessor take or took certain actions that result in the intended tax treatment of the Spin-Off not to be preserved), Vistra Energy may be required to make substantial indemnification payments to the other parties to the Tax Matters Agreement.

The Tax Matters Agreement also allocates the responsibility for taxes for periods prior to the Spin-Off between EFH Corp. and Vistra Energy. For periods prior to the Spin-Off, (i) Vistra Energy is generally required to reimburse EFH Corp. with respect to any taxes paid by EFH Corp. that are attributable to Vistra Energy and (ii) EFH Corp. is generally required to reimburse Vistra Energy with respect to any taxes paid by Vistra Energy that are attributable to EFH Corp.

Vistra Energy is also required to indemnify EFH Corp. against certain taxes in the event the IRS or another taxing authority successfully challenges the amount of gain relating to the PrefCo Preferred Stock Sale or the amount or allowance of EFH Corp.’s net operating loss deductions.

Vistra Energy’s indemnification obligations to EFH Corp. are not limited by any maximum amount. If Vistra Energy is required to indemnify EFH Corp. or such other persons under the circumstances set forth in the Tax Matters Agreement, Vistra Energy may be subject to substantial liabilities.

Vistra Energy is required to pay the holders of TRA Rights for certain tax benefits, which amounts are expected to be substantial.

On the Plan Effective Date, Vistra Energy entered into the Tax Receivable Agreement with American Stock Transfer & Trust Company, LLC, as the transfer agent. Pursuant to the Tax Receivable Agreement, Vistra Energy issued beneficial interests in the rights to receive payments under the Tax Receivable Agreement (the “TRA Rights”) to the first lien creditors of its Predecessor to be held in escrow for the benefit of the first lien creditors of its Predecessor entitled to receive such TRA Rights under the Plan of Reorganization. Vistra Energy’s pro forma financial statements included elsewhere in this joint proxy statement and prospectus reflect a liability of $708 million related to these future payment obligations. This amount is based on certain assumptions as described more fully in the notes to the pro forma financial statements, including assumptions on the current corporate tax rates remaining unchanged, and the actual payments made under the Tax Receivable Agreement could materially exceed this estimate.

The Tax Receivable Agreement provides for the payment by Vistra Energy to the holders of TRA Rights of 85% of the amount of cash savings, if any, in U.S. federal, state and local income tax that Vistra Energy and its subsidiaries actually realize as a result of its use of (a) the tax basis step-up attributable to the PrefCo Preferred Stock Sale, (b) the entire tax basis of the assets acquired as a result of the purchase and sale agreement, dated as

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of November 25, 2015 by and between La Frontera Ventures, LLC and Luminant, and (c) tax benefits related to imputed interest deemed to be paid by it as a result of payments under the Tax Receivable Agreement. The amount and timing of any payments under the Tax Receivable Agreement will vary depending upon a number of factors, including the amount and timing of the taxable income Vistra Energy generates in the future and the tax rate then applicable, its use of loss carryovers and the portion of its payments under the Tax Receivable Agreement constituting imputed interest.

Although Vistra Energy is not aware of any issue that would cause the IRS to challenge the tax benefits that are the subject of the Tax Receivable Agreement, recipients of the payments under the Tax Receivable Agreement will not be required to reimburse Vistra Energy for any payments previously made if such tax benefits are subsequently disallowed. As a result, in such circumstances, Vistra Energy could make payments under the Tax Receivable Agreement that are greater than its actual cash tax savings and may not be able to recoup those payments, which could adversely affect its liquidity.

Because Vistra Energy is a holding company with no operations of its own, its ability to make payments under the Tax Receivable Agreement is dependent on the ability of its subsidiaries to make distributions to it. To the extent that Vistra Energy is unable to make payments under the Tax Receivable Agreement because of the inability of its subsidiaries to make distributions to it for any reason, such payments will be deferred and will accrue interest until paid, which could adversely affect Vistra Energy’s results of operations and could also affect its liquidity in periods in which such payments are made.

The payments Vistra Energy will be required to make under the Tax Receivable Agreement could be substantial.

Vistra Energy may be required to make an early termination payment to the holders of TRA Rights under the Tax Receivable Agreement.

The Tax Receivable Agreement provides that, in the event that Vistra Energy breaches any of its material obligations under the Tax Receivable Agreement, or upon certain mergers, asset sales, or other forms of business combination or certain other changes of control, the transfer agent under the Tax Receivable Agreement may treat such event as an early termination of the Tax Receivable Agreement, in which case Vistra Energy would be required to make an immediate payment to the holders of the TRA Rights equal to the present value (at a discount rate equal to LIBOR plus 100 basis points) of the anticipated future tax benefits based on certain valuation assumptions.

As a result, upon any such breach or change of control, Vistra Energy could be required to make a lump sum payment under the Tax Receivable Agreement before it can realize any actual cash tax savings and such lump sum payment could be greater than its future actual cash tax savings.

The aggregate amount of these accelerated payments could be materially more than Vistra Energy’s estimated liability for payments made under the Tax Receivable Agreement set forth in its pro forma financial statements. Based on this estimation, Vistra Energy’s obligations under the Tax Receivable Agreement could have a substantial negative impact on its liquidity.

Vistra Energy is potentially liable for U.S. income taxes of the entire EFH Corp. consolidated group for all taxable years in which Vistra Energy was a member of such group.

Prior to the Spin-Off, EFH Corporate Services Company, EFH Properties Company and certain other subsidiary corporations were included in the consolidated U.S. federal income tax group of which EFH Corp. was the common parent (the “EFH Corp. Consolidated Group”). In addition, pursuant to the private letter ruling from the IRS that Vistra Energy received in connection with the Spin-Off, Vistra Energy will be considered a member of the EFH Corp. Consolidated Group immediately prior to the Spin-Off. Under U.S. federal income tax

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laws, any corporation that is a member of a consolidated group at any time during a taxable year is severally liable for the group’s entire U.S. federal income tax liability for the entire taxable year. In addition, entities that are disregarded for U.S. federal income tax purposes may be liable as successors under common law theories or under certain regulations to the extent corporations transferred assets to such entities or merged or otherwise consolidated into such entities, whether under state law or purely as a matter of U.S. federal income tax law. Thus, notwithstanding any contractual rights to be reimbursed or indemnified by EFH Corp. pursuant to the Tax Matters Agreement, to the extent EFH Corp. or other members of the EFH Corp. Consolidated Group fail to make any U.S. federal income tax payments required of them by law in respect of taxable years for which Vistra Energy or any subsidiary noted above was a member of the EFH Corp. Consolidated Group, Vistra Energy or such subsidiary may be liable for the shortfall. At such time, Vistra Energy may not have sufficient cash on hand to satisfy such payment obligation.

Vistra Energy’s ability to claim a portion of depreciation deductions may be limited for a period of time.

Under the Code, a corporation’s ability to utilize certain tax attributes, including depreciation, may be limited following an ownership change if the corporation’s overall asset tax basis exceeds the overall fair market value of its assets (after making certain adjustments). The Spin-Off resulted in an ownership change for Vistra Energy and it is expected that the overall tax basis of Vistra Energy’s assets may have exceeded the overall fair market value of its assets at such time. As a result, there may be a limitation on Vistra Energy’s ability to claim a portion of its depreciation deductions for a five-year period. This limitation could have a material impact on its tax liabilities and on its obligations under the Tax Receivable Agreement. In addition, any future ownership change of Vistra Energy following Emergence could likewise result in additional limitations on its ability to use certain tax attributes existing at the time of any such ownership change and have an impact on its tax liabilities and on its obligations under the Tax Receivable Agreement.

Vistra Energy’s businesses are subject to ongoing complex governmental regulations and legislation that have impacted, and may in the future impact, its businesses, results of operations, liquidity and financial condition.

Vistra Energy’s businesses operate in changing market environments influenced by various state and federal legislative and regulatory initiatives regarding the restructuring of the energy industry, including competition in power generation and sale of electricity. Although Vistra Energy attempts to comply with changing legislative and regulatory requirements, there is a risk that Vistra Energy will fail to adapt to any such changes successfully or on a timely basis.

Vistra Energy’s businesses are subject to numerous state and federal laws (including PURA, the Federal Power Act, the Atomic Energy Act, the Public Utility Regulatory Policies Act of 1978, the Clean Air Act (“CAA”), the Energy Policy Act of 2005 and the Dodd-Frank Wall Street Reform and Consumer Protection Act), changing governmental policy and regulatory actions (including those of the PUCT, the NERC, the TRE, the RCT, the TCEQ, the FERC, the MSHA, the EPA, the NRC and CFTC and the rules, guidelines and protocols of ERCOT with respect to various matters, including, but not limited to, market structure and design, operation of nuclear generation facilities, construction and operation of other generation facilities, development, operation and reclamation of lignite mines, recovery of costs and investments, decommissioning costs, market behavior rules, present or prospective wholesale and retail competition and environmental matters. Vistra Energy, along with other market participants, are subject to electricity pricing constraints and market behavior and other competition-related rules and regulations under PURA that are administered by the PUCT and ERCOT. Changes in, revisions to, or reinterpretations of, existing laws and regulations may have a material adverse effect on Vistra Energy. Further, in the future, Vistra Energy could expand its business, through acquisitions or otherwise, to geographic areas outside of Texas and the ERCOT market (e.g. such as through the Merger). Such expansion would subject it to additional state regulatory requirements that could have material adverse effect on Vistra Energy.

The Texas Legislature meets every two years. The next regular legislative session is scheduled to begin in January 2019. However, at any time the governor of Texas may convene a special session of the legislature.

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During any regular or special session, bills may be introduced that, if adopted, could materially and adversely affect its businesses, results of operations, liquidity and financial condition.

Vistra Energy is required to obtain, and to comply with, government permits and approvals.

Vistra Energy is required to obtain, and to comply with, numerous permits and licenses from federal, state and local governmental agencies. The process of obtaining and renewing necessary permits and licenses can be lengthy and complex and can sometimes result in the establishment of conditions that make the project or activity for which the permit or license was sought unprofitable or otherwise unattractive. In addition, such permits or licenses may be subject to denial, revocation or modification under various circumstances. Failure to obtain or comply with the conditions of permits or licenses, or failure to comply with applicable laws or regulations, may result in the delay or temporary suspension of Vistra Energy’s operations and electricity sales or the curtailment of its delivery of electricity to its customers and may subject it to penalties and other sanctions. Although various regulators routinely renew existing permits and licenses, renewal of Vistra Energy’s existing permits or licenses could be denied or jeopardized by various factors, including (a) failure to provide adequate financial assurance for closure, (b) failure to comply with environmental, health and safety laws and regulations or permit conditions, (c) local community, political or other opposition and (d) executive, legislative or regulatory action.

Vistra Energy’s inability to procure and comply with the permits and licenses required for its operations, or the cost to Vistra Energy of such procurement or compliance, could have a material adverse effect on Vistra Energy. In addition, new environmental legislation or regulations, if enacted, or changed interpretations of existing laws, may cause routine maintenance activities at Vistra Energy’s facilities to need to be changed in order to avoid violating applicable laws and regulations or elicit claims that historical routine maintenance activities at its facilities violated applicable laws and regulations. In addition to the possible imposition of fines in the case of any such violations, Vistra Energy may be required to undertake significant capital investments in emissions control technology and obtain additional operating permits or licenses, which could have a material adverse effect on Vistra Energy.

Vistra Energy’s cost of compliance with existing and new environmental laws could have a material adverse effect on Vistra Energy.

Vistra Energy is subject to extensive environmental regulation by governmental authorities, including the EPA and the TCEQ. Vistra Energy may incur significant additional costs beyond those currently contemplated to comply with these regulatory requirements. If Vistra Energy fails to comply with these regulatory requirements, it could be subject to civil or criminal liabilities and fines. Existing environmental regulations could be revised or reinterpreted, new laws and regulations could be adopted or become applicable to Vistra Energy or its facilities, and future changes in environmental laws and regulations could occur, including potential regulatory and enforcement developments related to air emissions, all of which could result in significant additional costs beyond those currently contemplated to comply with existing requirements. Any of the foregoing could have a material adverse effect on Vistra Energy.

The EPA has recently finalized or proposed several regulatory actions establishing new requirements for control of certain emissions from sources, including electricity generation facilities. In the future, the EPA may also propose and finalize additional regulatory actions that may adversely affect Vistra Energy’s existing generation facilities or its ability to cost-effectively develop new generation facilities. There is no assurance that the currently installed emissions control equipment at Vistra Energy’s lignite, coal and/or natural gas-fueled generation facilities will satisfy the requirements under any future EPA or TCEQ regulations. Some of the recent regulatory actions and proposed actions, such as the EPA’s Regional Haze Federal Implementation Plans (FIP) for reasonable progress and best available retrofit technology (BART), could require Vistra Energy to install significant additional control equipment, resulting in potentially material costs of compliance for its generation units, including capital expenditures, higher operating and fuel costs and potential production curtailments if the rules take effect as proposed or finalized. These costs could have a material adverse effect on Vistra Energy.

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Vistra Energy may not be able to obtain or maintain all required environmental regulatory approvals. If there is a delay in obtaining any required environmental regulatory approvals, if Vistra Energy fails to obtain, maintain or comply with any such approval or if an approval is retroactively disallowed or adversely modified, the operation of its generation facilities could be stopped, disrupted, curtailed or modified or become subject to additional costs. Any such stoppage, disruption, curtailment, modification or additional costs could have a material adverse effect on Vistra Energy.

In addition, Vistra Energy may be responsible for any on-site liabilities associated with the environmental condition of facilities that it has acquired, leased or developed, regardless of when the liabilities arose and whether they are now known or unknown. In connection with certain acquisitions and sales of assets, Vistra Energy may obtain, or be required to provide, indemnification against certain environmental liabilities. Another party could, depending on the circumstances, assert an environmental claim against Vistra Energy or fail to meet its indemnification obligations to Vistra Energy.

Vistra Energy could be materially and adversely affected if current regulations are implemented or if new federal or state legislation or regulations are adopted to address global climate change, or if Vistra Energy is subject to lawsuits for alleged damage to persons or property resulting from GHG emissions.

There is a concern nationally and internationally about global climate change and how GHG emissions, such as CO₂, contribute to global climate change. Over the last several years, the United States Congress has considered and debated, and President Obama’s administration previously discussed, several proposals intended to address climate change using different approaches, including a cap on carbon emissions with emitters allowed to trade unused emission allowances (cap-and-trade), a tax on carbon or GHG emissions, incentives for the development of low-carbon technology and federal renewable portfolio standards. The EPA has also finalized regulations under the CAA Act to limit CO₂ emissions from existing generating units, referred to as the Clean Power Plan. While currently the subject of a legal challenge, if implemented as finalized, the Clean Power Plan would require the closure of a significant number of coal-fueled electric generating units nationwide and in Texas. In addition, a number of federal court cases have been filed in recent years asserting damage claims related to GHG emissions, and the results in those proceedings could establish adverse precedent that might apply to companies (including it) that produce GHG emissions. Vistra Energy could be materially and adversely affected if new federal and/or state legislation or regulations are adopted to address global climate change, if the Clean Power Plan is implemented as finalized or if Vistra Energy is subject to lawsuits for alleged damage to persons or property resulting from GHG emissions.

The availability and cost of emission allowances could adversely impact Vistra Energy’s costs of operations.

Vistra Energy is required to maintain, through either allocations or purchases, sufficient emission allowances for SO₂ and NO_x to support its operations in the ordinary course of operating its power generation facilities. These allowances are used to meet the obligations imposed on Vistra Energy by various applicable environmental laws. If Vistra Energy’s operational needs require more than its allocated allowances, Vistra Energy may be forced to purchase such allowances on the open market, which could be costly. If Vistra Energy is unable to maintain sufficient emission allowances to match its operational needs, Vistra Energy may have to curtail its operations so as not to exceed its available emission allowances, or install costly new emission controls. As Vistra Energy uses the emission allowances that it has purchased on the open market, costs associated with such purchases will be recognized as operating expense. If such allowances are available for purchase, but only at significantly higher prices, the purchase of such allowances could materially increase Vistra Energy’s costs of operations in the affected markets.

Luminant’s mining operations are subject to RCT oversight.

Vistra Energy currently owns and operates through Luminant 11 surface lignite coal mines in Texas to provide fuel for its electricity generation facilities. The RCT, which exercises broad authority to regulate

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reclamation activity, reviews on an ongoing basis whether Luminant is compliant with RCT rules and regulations and whether it has met all of the requirements of its mining permits. Any new rules and regulations adopted by the RCT or the Department of Interior Office of Surface Mining, which also regulates mining activity nationwide, or any changes in the interpretation of existing rules and regulations, could result in higher compliance costs or otherwise adversely affect Vistra Energy’s financial condition or cause a revocation of a mining permit. Any revocation of a mining permit would mean that Luminant would no longer be allowed to mine lignite at the applicable mine to serve its generation facilities. In addition, Luminant’s mining reclamation obligations are secured by a first lien on its assets which is pari passu with the Vistra Operations Credit Facilities (but which would be paid first, up to $975 million, upon any liquidation of Vistra Operations Company LLC’s (“Vistra Operations”) assets). The RCT could, at any time, require that Luminant’s mining reclamation obligations be secured by cash or letters of credit in lieu of such first lien. Any failure to provide any such cash or letter of credit collateral could result in Luminant no longer being able to mine lignite. Any such event could have a material adverse effect on Vistra Energy.

Luminant’s lignite mining reclamation activity will require significant resources as existing and retired mining operations are reclaimed over the next several years.

In conjunction with Luminant’s recent announcements to retire several power generation assets and related mining operations, along with the continuous reclamation activity at its continuing mining operations for its mines related to the Oak Grove and Martin Lake generation assets, Luminant is expected to spend a significant amount of money, internal resources and time to complete the required reclamation activities. For the next five years, Vistra Energy is projected to spend up to $400 million (on a nominal basis) to achieve its reclamation objectives across all of its mining operations.

Litigation, legal proceedings, regulatory investigations or other administrative proceedings could expose Vistra Energy to significant liabilities and reputation damage that could have a material adverse effect on Vistra Energy.

Vistra Energy is involved in the ordinary course of business in a number of lawsuits involving, among other matters, employment, commercial, and environmental issues, and other claims for injuries and damages. Vistra Energy evaluates litigation claims and legal proceedings to assess the likelihood of unfavorable outcomes and to estimate, if possible, the amount of potential losses. Based on these evaluations and estimates, when required by applicable accounting rules, Vistra Energy establishes reserves and discloses the relevant litigation claims or legal proceedings, as appropriate. These evaluations and estimates are based on the information available to management at the time and involve a significant amount of judgment. Actual outcomes or losses may differ materially from current evaluations and estimates. The settlement or resolution of such claims or proceedings may have a material adverse effect on Vistra Energy. Vistra Energy uses appropriate means to contest litigation threatened or filed against it, but the litigation environment poses a significant business risk.

Vistra Energy is also involved in the ordinary course of business in regulatory investigations and other administrative proceedings, and Vistra Energy is exposed to the risk that it may become the subject of additional regulatory investigations or administrative proceedings. While Vistra Energy cannot predict the outcome of any regulatory investigation or administrative proceeding, any such regulatory investigation or administrative proceeding could result in it incurring material penalties and/or other costs and have a materially adverse effect on Vistra Energy.

The REP certification of Vistra Energy’s retail operation is subject to PUCT review.

The PUCT may at any time initiate an investigation into whether Vistra Energy’s retail operation complies with certain PUCT rules and whether it has met all of the requirements for REP certification, including financial requirements. Any removal or revocation of a REP certification would mean that Vistra Energy would no longer be allowed to provide electricity service to retail customers. Such decertification could have a material adverse

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effect on Vistra Energy. Moreover, any capital or other expenditures that Vistra Energy is required by the PUCT to undertake in order to achieve or maintain any such compliance could also have a material adverse effect on Vistra Energy.

Vistra Energy’s retail operations are subject to significant competition from other REPs, which could result in a loss of existing customers and the inability to attract new customers.

Vistra Energy operates in a very competitive retail market and, as a result, its retail operation faces significant competition for customers. Vistra Energy believes its TXU Energy^TM brand is viewed favorably in the retail electricity markets in which it operates, but despite Vistra Energy’s commitment to providing superior customer service and innovative products, customer sentiment toward its brand, including by comparison to its competitors’ brands, depends on certain factors beyond its control. For example, competitor REPs may offer lower electricity prices and other incentives, which, despite Vistra Energy’s long-standing relationship with many customers, may attract customers away from it. If Vistra Energy is unable to successfully compete with competitors in the retail market it is possible its retail customer counts could continue to decline, which could have a material adverse effect on Vistra Energy.

As Vistra Energy tries to grow its retail business and operate its business strategy, Vistra Energy competes with various other REPs that may have certain advantages over it. For example, in new markets, Vistra Energy’s principal competitor for new customers may be the incumbent REP, which has the advantage of long-standing relationships with its customers, including well-known brand recognition. In addition to competition from the incumbent REP, Vistra Energy may face competition from a number of other energy service providers, other energy industry participants, or nationally branded providers of consumer products and services who may develop businesses that will compete with Vistra Energy. Some of these competitors or potential competitors may be larger than Vistra Energy is or have greater resources or access to capital than Vistra Energy has. If there is inadequate potential margin in retail electricity markets with substantial competition to overcome the adverse effect of relatively high customer acquisition costs in such markets, it may not be profitable for Vistra Energy to compete in these markets.

Vistra Energy’s retail operations rely on the infrastructure of local utilities or independent transmission system operators to provide electricity to, and to obtain information about, its customers. Any infrastructure failure could negatively impact customer satisfaction and could have a material adverse effect on Vistra Energy.

Vistra Energy’s retail operations depend on transmission and distribution facilities owned and operated by unaffiliated utilities to deliver the electricity that Vistra Energy sells to its customers. If transmission capacity is inadequate, its ability to sell and deliver electricity may be hindered and Vistra Energy may have to forgo sales or buy more expensive wholesale electricity than is available in the capacity-constrained area. For example, during some periods, transmission access is constrained in some areas of the Dallas-Fort Worth metroplex, where Vistra Energy has a significant number of customers. The cost to provide service to these customers may exceed the cost to provide service to other customers, resulting in lower operating margins. In addition, any infrastructure failure that interrupts or impairs delivery of electricity to Vistra Energy’s customers could negatively impact customer satisfaction with its service. Any of the foregoing could have a material adverse effect on Vistra Energy.

Vistra Energy may suffer material losses, costs and liabilities due to ownership and operation of the Comanche Peak nuclear generation facility.

Vistra Energy owns and operates a nuclear generation facility in Glen Rose, Texas (the “Comanche Peak Facility”). The ownership and operation of a nuclear generation facility involves certain risks. These risks include:

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The prolonged unavailability of the Comanche Peak Facility could have a material adverse effect on Vistra Energy’s results of operation, cash flows, financial position and reputation. The following are among the more significant related risks:

The operation and maintenance of power generation facilities and related mining operations involve significant risks that could adversely affect Vistra Energy’s results of operations, liquidity and financial condition.

The operation and maintenance of power generation facilities and related mining operations involve many risks, including, as applicable, start-up risks, breakdown or failure of facilities, operator error, lack of sufficient

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capital to maintain the facilities, the dependence on a specific fuel source or the impact of unusual or adverse weather conditions or other natural events, or terrorist attacks, as well as the risk of performance below expected levels of output, efficiency or reliability, the occurrence of any of which could result in substantial lost revenues and/or increased expenses. A significant number of Vistra Energy’s facilities were constructed many years ago. In particular, older generating equipment, even if maintained in accordance with good engineering practices, may require significant capital expenditures to operate at peak efficiency or reliability. The risk of increased maintenance and capital expenditures arises from (a) increased starting and stopping of generation equipment due to the volatility of the competitive generation market and the prospect of continuing low wholesale electricity prices that may not justify sustained or year-round operation of all its generation facilities, (b) any unexpected failure to generate power, including failure caused by equipment breakdown or unplanned outage (whether by order of applicable governmental regulatory authorities, the impact of weather events or natural disasters or otherwise), (c) damage to facilities due to storms, natural disasters, wars, terrorist or cyber/data security acts and other catastrophic events and (d) the passage of time and normal wear and tear. Further, Vistra Energy’s ability to successfully and timely complete routine maintenance or other capital projects at its existing facilities is contingent upon many variables and subject to substantial risks. Should any such efforts be unsuccessful, Vistra Energy could be subject to additional costs or losses and write downs of its investment in the project.

Vistra Energy cannot be certain of the level of capital expenditures that will be required due to changing environmental and safety laws and regulations (including changes in the interpretation or enforcement thereof), needed facility repairs and unexpected events (such as natural disasters or terrorist or cyber/data security attacks). The unexpected requirement of large capital expenditures could have a material adverse effect on Vistra Energy.

In addition, if any of Vistra Energy’s generation facilities experiences unplanned outages, whether because of equipment breakdown or otherwise, Vistra Energy may be required to procure replacement power at spot market prices in order to fulfill contractual commitments. If Vistra Energy does not have adequate liquidity to meet margin and collateral requirements, Vistra Energy may be exposed to significant losses, may miss significant opportunities and may have increased exposure to the volatility of spot markets, which could have a material adverse effect on Vistra Energy.

Vistra Energy’s employees, contractors, customers and the general public may be exposed to a risk of injury due to the nature of its operations.

Vistra Energy’s employees and contractors work in, and customers and the general public may be exposed to, potentially dangerous environments at or near its operations. As a result, employees, contractors, customers and the general public are at risk for serious injury, including loss of life. Significant examples of such risks include nuclear accidents, dam failure, gas explosions, mine area collapses and other dangerous incidents.

The occurrence of any one of these events may result in Vistra Energy being named as a defendant in lawsuits asserting claims for substantial damages, including for environmental cleanup costs, personal injury and property damage and fines and/or penalties. Vistra Energy maintains an amount of insurance protection that Vistra Energy considers adequate, but Vistra Energy cannot provide any assurance that its insurance will be sufficient or effective under all circumstances and against all hazards or liabilities to which Vistra Energy may be subject and, even if Vistra Energy does have insurance coverage for a particular circumstance, Vistra Energy may be subject to a large deductible and maximum cap. Further, due to rising insurance costs and changes in the insurance markets, Vistra Energy cannot provide any assurance that its insurance coverage will continue to be available at all or at rates or on terms similar to those presently available. Any losses not covered by insurance could have a material adverse effect on Vistra Energy.

Vistra Energy may be materially and adversely affected by the effects of extreme weather conditions and seasonality.

Vistra Energy may be materially affected by weather conditions and its businesses may fluctuate substantially on a seasonal basis as the weather changes. In addition, Vistra Energy could be subject to the effects

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of extreme weather conditions, including sustained cold or hot temperatures, hurricanes, storms or other natural disasters, which could stress its generation facilities and result in outages, destroy its assets and result in casualty losses that are not ultimately offset by insurance proceeds, and could require increased capital expenditures or maintenance costs, including supply chain costs.

Moreover, an extreme weather event could cause disruption in service to customers due to downed wires and poles or damage to other operating equipment, which could result in Vistra Energy foregoing sales of electricity and lost revenue. Similarly, an extreme weather event might affect the availability of generation and transmission capacity, limiting Vistra Energy’s ability to source or deliver power where it is needed or limit its ability to source fuel for its plants (including due to damage to rail or natural gas pipeline infrastructure). Additionally, extreme weather may result in unexpected increases in customer load, requiring Vistra Energy’s retail operation to procure additional electricity supplies at wholesale prices in excess of customer sales prices for electricity. These conditions, which cannot be reliably predicted, could have adverse consequences by requiring Vistra Energy to seek additional sources of electricity when wholesale market prices are high or to sell excess electricity when market prices are low, which could have a material adverse effect on Vistra Energy.

Changes in technology or increased electricity conservation efforts may reduce the value of Vistra Energy’s generation facilities and may otherwise have a material adverse effect on Vistra Energy.

Technological advances have improved, and are likely to continue to improve, for existing and alternative methods to produce and store power, including gas turbines, wind turbines, fuel cells, micro turbines, photovoltaic (solar) cells, batteries and concentrated solar thermal devices, along with improvements in traditional technologies. Such technological advances have reduced, and are expected to continue to reduce, the costs of power production or storage to a level that will enable these technologies to compete effectively with traditional generation facilities. Consequently, the value of Vistra Energy’s more traditional generation assets could be significantly reduced as a result of these competitive advances, which could have a material adverse effect on Vistra Energy. In addition, changes in technology have altered, and are expected to continue to alter, the channels through which retail customers buy electricity (i.e., self-generation or distributed-generation facilities). To the extent self-generation facilities become a more cost-effective option for ERCOT customers, Vistra Energy’s financial condition, operating cash flows and results of operations could be materially and adversely affected.

Technological advances in demand-side management and increased conservation efforts have resulted, and are expected to continue to result, in a decrease in electricity demand. A significant decrease in electricity demand in ERCOT as a result of such efforts would significantly reduce the value of Vistra Energy’s generation assets. Certain regulatory and legislative bodies have introduced or are considering requirements and/or incentives to reduce power consumption. Effective power conservation by its customers could result in reduced electricity demand or significantly slow the growth in such demand. Any such reduction in demand could have a material adverse effect on Vistra Energy. Furthermore, Vistra Energy may incur increased capital expenditures if Vistra Energy is required to increase investment in conservation measures.

Attacks on Vistra Energy’s infrastructure that breach cyber/data security measures could expose it to significant liabilities and reputation damage and disrupt business operations, which could have a material adverse effect on Vistra Energy.

Much of Vistra Energy’s information technology infrastructure is connected (directly or indirectly) to the internet. There have been numerous attacks on government and industry information technology systems through the internet that have resulted in material operational, reputation and/or financial costs. While Vistra Energy has controls in place designed to protect its infrastructure and Vistra Energy is not aware of any significant breaches in the past, a breach of cyber/data security measures that impairs its information technology infrastructure could disrupt normal business operations and affect its ability to control its generation assets, access retail customer information and limit communication with third parties. Any loss of confidential or proprietary data through a

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breach could adversely affect Vistra Energy’s reputation, expose it to material legal or regulatory claims and impair its ability to execute its business strategy, which could have a material adverse effect on Vistra Energy.

As part of the continuing development of new and modified reliability standards, the FERC has approved changes to its Critical Infrastructure Protection reliability standards and has established standards for assets identified as “critical cyber assets.” Under the Energy Policy Act of 2005, the FERC can impose penalties (up to $1 million per day, per violation) for failure to comply with mandatory electric reliability standards, including standards to protect the power system against potential disruptions from cyber/data and physical security breaches.

Further, Vistra Energy’s retail business requires access to sensitive customer data in the ordinary course of business. Examples of sensitive customer data are names, addresses, account information, historical electricity usage, expected patterns of use, payment history, credit bureau data, credit and debit card account numbers, drivers’ license numbers, social security numbers and bank account information. Vistra Energy’s retail business may need to provide sensitive customer data to vendors and service providers who require access to this information in order to provide services, such as call center operations, to the retail business. If a significant breach were to occur, the reputation of its retail business may be adversely affected, customer confidence may be diminished, and Vistra Energy’s retail business may be subject to substantial legal or regulatory claims, any of which may contribute to the loss of customers and have a material adverse effect on Vistra Energy.

The loss of the services of Vistra Energy’s key management and personnel could adversely affect its ability to successfully operate its businesses.

Vistra Energy’s future success will depend on its ability to continue to attract and retain highly qualified personnel. Vistra Energy competes for such personnel with many other companies, in and outside of its industry, government entities and other organizations. Vistra Energy may not be successful in retaining current personnel or in hiring or retaining qualified personnel in the future. Its failure to attract highly qualified new personnel or retain highly qualified existing personnel could have an adverse effect on Vistra Energy’s ability to successfully operate its businesses.

Vistra Energy could be materially and adversely impacted by strikes or work stoppages by its unionized employees.

As of December 31, 2017, Vistra Energy had 1,628 employees covered by collective bargaining agreements. Such collective bargaining agreements expired on March 31, 2017, but remain effective pursuant to evergreen provisions unless and until terminated on prior notice by either party. Vistra Energy is currently negotiating new collective bargaining agreements with all three of its local unions. In the event that its union employees strike, participate in a work stoppage or slowdown or engage in other forms of labor strife or disruption, Vistra Energy would be responsible for procuring replacement labor or it could experience reduced power generation or outages. Vistra Energy’s ability to procure such labor is uncertain. Strikes, work stoppages or the inability to negotiate future collective bargaining agreements on favorable terms or at all could have a material adverse effect on Vistra Energy.

Vistra Energy is a holding company and its ability to obtain funds from its subsidiaries is structurally subordinated to existing and future liabilities and preferred equity of its subsidiaries.

Vistra Energy is a holding company that does not conduct any business operations of its own. As a result, Vistra Energy’s cash flows and ability to meet its obligations are largely dependent upon the operating cash flows of Vistra Energy’s subsidiaries and the payment of such operating cash flows to Vistra Energy in the form of dividends, distributions, loans or otherwise. These subsidiaries are separate and distinct legal entities from Vistra Energy and have no obligation (other than any existing contractual obligations) to provide Vistra Energy with funds to satisfy its obligations. Any decision by a subsidiary to provide Vistra Energy with funds to satisfy

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its obligations, including those under the Tax Receivable Agreement, whether by dividends, distributions, loans or otherwise, will depend on, among other things, such subsidiary’s results of operations, financial condition, cash flows, cash requirements, contractual prohibitions and other restrictions, applicable law and other factors. The deterioration of income from, or other available assets of, any such subsidiary for any reason could limit or impair its ability to pay dividends or make other distributions to Vistra Energy.

Vistra Energy may not pay any dividends on its common stock in the future.

Vistra Energy has no present intention to pay cash dividends on its common stock. Any determination to pay dividends to holders of its common stock in the future will be at the sole discretion of the Vistra Energy Board and will depend upon many factors, including Vistra Energy’s historical and anticipated financial condition, cash flows, liquidity and results of operations, capital requirements, market conditions, its growth strategy and the availability of growth opportunities, contractual prohibitions and other restrictions with respect to the payment of dividends, applicable law and other factors that the Vistra Energy Board deems relevant.

A small number of stockholders could be able to significantly influence Vistra Energy’s business and affairs.

The three largest groups of stockholders of Vistra Energy, affiliates of Apollo Management Holdings L.P. (collectively, the “Apollo Entities”), affiliates of Brookfield Asset Management Private Institutional Capital Adviser (Canada), L.P. (collectively, the “Brookfield Entities”), and affiliates of Oaktree Capital Management, L.P. (collectively, the “Oaktree Entities,” and together with the Apollo Entities and the Brookfield Entities, the “Vistra Energy Principal Stockholders”), all of which were first lien creditors of its Predecessor prior to Emergence, collectively currently own approximately 39% of Vistra Energy Common Stock outstanding. Large holders such as the Vistra Energy Principal Stockholders may be able to affect matters requiring approval by holders of Vistra Energy Common Stock, including the election of directors and the approval of any strategic transactions. The Vistra Energy Principal Stockholders entered into the Vistra Energy Stockholder Support Agreement in connection with the Merger pursuant to which they have agreed, subject to certain circumstances, to vote their shares of Vistra Energy Common Stock in favor of the Merger Proposal and the Stock Issuance Proposal. See “Agreements Related to the Merger—The Merger Support Agreements” beginning on page 158 for more information. Furthermore, pursuant to the terms of Stockholders Agreements entered into with each of the Vistra Energy Principal Stockholders, each Vistra Energy Principal Stockholder is entitled to designate one director to serve on the Vistra Energy Board as a Class III director for so long as it beneficially owns, in the aggregate, at least 22,500,000 shares of Vistra Energy Common Stock. It is expected that each Vistra Energy Principal Stockholder will own enough equity in the combined company that each will still have a representative on the combined company’s board of directors. See “Information About Vistra Energy—Certain Relationships and Related Party Transactions—Stockholder’s Agreements” beginning on page 273 for more information.

Conflicts of interest may arise because some members of the Vistra Energy Board are representatives of the Vistra Energy Principal Stockholders.

The Vistra Energy Principal Stockholders could invest in entities that directly or indirectly compete with Vistra Energy. As a result of these relationships, when conflicts arise between the interests of the Vistra Energy Principal Stockholders or their affiliates and the interests of other stockholders, members of the Vistra Energy Board that are representatives of the Vistra Energy Principal Stockholders may not be disinterested. Neither the Vistra Energy Principal Stockholders nor the representatives of the Vistra Energy Principal Stockholders on the Vistra Energy Board, by the terms of the Vistra Energy certificate of incorporation, are required to offer Vistra Energy any transaction opportunity of which they become aware and could take any such opportunity for themselves or offer it to their other affiliates, unless such opportunity is expressly offered to them solely in their capacity as members of the Vistra Energy Board.

Additionally, pursuant to the Oaktree Letter Agreement described in “Agreements Related to the Merger—The Oaktree Letter Agreement” beginning on page 158, affiliates of Oaktree commit to use commercially reasonable efforts to divest a portion of their shares of Vistra Energy Common Stock or Dynegy Common Stock,

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but are not obligated to consummate such divestment other than at prices per share of Dynegy Common Stock or Vistra Energy Common Stock determined from time to time in Oaktree’s sole and absolute discretion to be adequate. The Vistra Energy Stockholder Support Agreement provides that if affiliates of Oaktree have not sold the number of shares of Vistra Energy Common Stock or Dynegy Common Stock contemplated in the Oaktree Letter Agreement, then Dynegy will purchase shares of Dynegy Common Stock from such affiliates of Oaktree so that the target ownership level is met. Such purchase will be consummated immediately prior to the closing of the Merger and will be for a cash purchase price of $13.24 per share.

Vistra Energy is unable to take certain actions because such actions could jeopardize the intended tax treatment of the Spin-Off, and such restrictions could be significant.

The Tax Matters Agreement prohibits Vistra Energy from taking certain actions that could reasonably be expected to undermine the intended tax treatment the Spin-Off or to jeopardize the conclusions of the IRS private letter ruling Vistra Energy received in connection with the Spin-Off or opinions of counsel received by Vistra Energy or EFH Corp. In particular, for two years after the Spin-Off, Vistra Energy may not:

Nevertheless, Vistra Energy is permitted to take any of the actions described above if (a) it obtains written consent from EFH Corp., (b) such action or transaction is described in or otherwise consistent with the facts in the private letter ruling Vistra Energy obtained from the IRS in connection with the Spin- Off, (c) Vistra Energy obtains a supplemental private letter ruling from the IRS or (d) Vistra Energy obtains an unqualified opinion of a nationally recognized law or accounting firm that is reasonably acceptable to EFH Corp. that the action will not affect the intended tax treatment of the Spin-Off.

The covenants and other limitations with respect to the Tax Matters Agreement may limit Vistra Energy’s ability to undertake certain transactions that would otherwise be value-maximizing.

Provisions in the certificate of incorporation and bylaws and the Tax Receivable Agreement might discourage, delay or prevent a change in control of Vistra Energy or changes in its management and therefore depress the market price of Vistra Energy Common Stock.

The certificate of incorporation and bylaws of Vistra Energy, and the Tax Receivable Agreement contain provisions that could depress the market price of Vistra Energy Common Stock by acting to discourage, delay or prevent a change in control of Vistra Energy or changes in its management that stockholders may deem advantageous. These provisions are in its bylaws:

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In addition, the Tax Receivable Agreement provides that upon certain mergers, asset sales or other forms of business combination or certain other changes of control, the transfer agent under the Tax Receivable Agreement may treat such event as an early termination of the Tax Receivable Agreement, in which case Vistra Energy would be required to make a lump-sum payment under the Tax Receivable Agreement, which could be significant. This payment obligation may discourage potential buyers from acquiring Vistra Energy.

Risks Related to Dynegy

Dynegy is, and will continue to be, subject to the risks described in Part I, Item 1A in Dynegy’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016 and the risks described in Part II, Item IA in Dynegy’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, as filed with the SEC and incorporated by reference into this joint proxy statement and prospectus. See “Where You Can Find More Information and Incorporation by Reference” on page 309.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This joint proxy statement and prospectus and the annexes to this joint proxy statement and prospectus contain forward looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act and Section 21E of the Exchange Act.

These forward-looking statements are predictions and generally can be identified by use of statements that include phrases such as “may,” “believe,” “expect,” “anticipate,” “intend,” “estimate,” “project,” “target,” “goal,” “plan,” “should,” “will,” “predict,” “potential,” “likely,” or other words, phrases or expressions of similar import, or the negative or other words or expressions of similar meaning, and statements regarding the anticipated consequences and benefits of the Merger or the other transactions contemplated by the Merger Agreement or the future financial condition, results of operations and business of Vistra Energy, Dynegy or the combined company.

Without limiting the generality of the preceding sentence, certain information contained in the sections “The Merger—Background of the Merger,” “The Merger—The Recommendation of the Vistra Energy Board and Its Reasons for the Merger,” “The Merger—Dynegy’s Reasons for the Merger; Recommendation of the Dynegy Board,” “The Merger—Certain Vistra Energy Unaudited Prospective Financial Information,” and “The Merger—Certain Dynegy Unaudited Prospective Financial Information” constitute forward-looking statements.

The management teams of each of Vistra Energy and Dynegy base these forward-looking statements on particular assumptions that they have made in light of their industry experience, as well as their perception of historical trends, current conditions, expected future developments and other factors that they believe are appropriate under the circumstances. The forward-looking statements are necessarily estimates reflecting the judgment of Vistra Energy’s and Dynegy’s respective management teams and involve a number of known and unknown risks, uncertainties and other factors, many of which are difficult to predict or beyond Vistra Energy’s and Dynegy’s control, which may cause actual results, performance, or achievements of Vistra Energy, Dynegy or the combined company to be materially different from those expressed or implied by the forward-looking statements. In addition to other factors and matters contained in this joint proxy statement and prospectus, including those disclosed under “Risk Factors” beginning on page 35, these forward-looking statements are subject to risks, uncertainties and other factors, including, among others: