IMPORTANT ADDITIONAL INFORMATION AND WHERE TO FIND IT:
In connection with the proposed merger (the “Proposed Transaction”) between ONEOK and Magellan, ONEOK intends to file with the Securities and
Exchange Commission (the “SEC”) a registration statement on Form S-4 (the “Registration Statement”) to register the shares of ONEOK’s common stock to be issued in connection with the
Proposed Transaction. The Registration Statement will include a document that serves as a prospectus of ONEOK and joint proxy statement of ONEOK and Magellan (the “joint proxy statement/prospectus”), and each party will file other
documents regarding the Proposed Transaction with the SEC. INVESTORS AND SECURITY HOLDERS OF ONEOK AND MAGELLAN ARE URGED TO CAREFULLY AND THOROUGHLY READ, WHEN THEY BECOME AVAILABLE, THE REGISTRATION STATEMENT, THE JOINT PROXY
STATEMENT/PROSPECTUS, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND OTHER RELEVANT DOCUMENTS FILED BY ONEOK AND MAGELLAN WITH THE SEC BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT ONEOK AND MAGELLAN, THE PROPOSED TRANSACTION,
THE RISKS RELATED THERETO AND RELATED MATTERS.
After the Registration Statement has been declared effective, a definitive joint proxy
statement/prospectus will be mailed to shareholders of ONEOK and unitholders of Magellan. Investors will be able to obtain free copies of the Registration Statement and the joint proxy statement/prospectus, as each may be amended from time to time,
and other relevant documents filed by ONEOK and Magellan with the SEC (when they become available) through the website maintained by the SEC at www.sec.gov. Copies of documents filed with the SEC by ONEOK, including the joint proxy
statement/prospectus (when available), will be available free of charge from ONEOK’s website at www.oneok.com under the “Investors” tab. Copies of documents filed with the SEC by Magellan, including the joint proxy
statement/prospectus (when available), will be available free of charge from Magellan’s website at www.magellanlp.com under the “Investors” tab.
PARTICIPANTS IN THE SOLICITATION:
ONEOK and
certain of its directors, executive officers and other members of management and employees, Magellan, and certain of the directors, executive officers and other members of management and employees of Magellan GP, LLC, which manages the business and
affairs of Magellan, may be deemed to be participants in the solicitation of proxies from ONEOK’s shareholders and the solicitation of proxies from Magellan’s unitholders, in each case with respect to the Proposed Transaction. Information
about ONEOK’s directors and executive officers is available in ONEOK’s Annual Report on Form 10-K for the 2022 fiscal year filed with the SEC on February 28, 2023, and its definitive proxy
statement for the 2023 annual meeting of stockholders filed with the SEC on April 5, 2023, and in the joint proxy statement/prospectus (when available). Information about Magellan’s directors and executive officers is available in its
Annual Report on Form 10-K for the 2022 fiscal year and its definitive proxy statement for the 2023 annual meeting of unitholders, each filed with the SEC on February 21, 2023, and the joint proxy
statement/prospectus (when available). Other information regarding the participants in the solicitations and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the Registration Statement,
the joint proxy statement/prospectus and other relevant materials to be filed with the SEC regarding the Proposed Transaction when they become available. Shareholders of ONEOK, unitholders of Magellan, potential investors and other readers should
read the joint proxy statement/prospectus carefully when it becomes available before making any voting or investment decisions.
NO OFFER OR
SOLICITATION:
This communication is not intended to and shall not constitute an offer to sell or the solicitation of an offer to sell or the
solicitation of an offer to buy any securities or a solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or
qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.
FORWARD-LOOKING STATEMENTS:
This communication
contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of
historical fact, included in this communication that address activities, events or developments that ONEOK or Magellan expects, believes or anticipates will or may occur in the future are forward-looking statements. Words such as
“estimate,” “project,” “predict,” “believe,” “expect,” “anticipate,” “potential,” “create,” “intend,” “could,” “would,” “may,”
“plan,” “will,” “guidance,” “look,” “goal,” “future,” “build,” “focus,” “continue,” “strive,” “allow” or the negative of such terms or
other variations thereof and words and terms of similar substance used in connection with any discussion of future plans, actions, or events identify forward-looking statements. However, the absence of these words does not mean that the statements
are not forward-looking. These forward-looking statements include, but are not limited to, statements regarding the Proposed Transaction, the expected closing of the Proposed Transaction and the timing thereof and as adjusted descriptions of the
post-Transaction company and its operations, strategies and plans, integration, debt levels and leverage ratio, capital expenditures, cash flows and anticipated uses thereof, synergies, opportunities and anticipated future performance, including
maintaining current ONEOK management, enhancements to investment-grade credit profile, an expected accretion to earnings and free cash flow, dividend payments and potential share repurchases, increase in value of tax attributes and expected impact
on EBITDA. Information adjusted for the Proposed Transaction should not be considered a forecast of future results. There are a number of risks and uncertainties that could cause actual results to differ materially from the forward-looking
statements included in this communication. These include the risk that ONEOK’s and Magellan’s businesses will not be integrated successfully; the risk that cost savings, synergies and growth from the Proposed Transaction may not be fully
realized or may take longer to realize than expected; the risk that the credit ratings of the combined company or its subsidiaries may be different from what the companies expect; the possibility that shareholders of ONEOK may not approve the
issuance of new shares of ONEOK common stock in the Proposed Transaction or that shareholders of ONEOK or unitholders of Magellan may not approve the Proposed Transaction; the risk that a condition to closing of the Proposed Transaction may not be
satisfied, that either party may terminate the Merger Agreement or that the closing of the Proposed Transaction might be delayed or not occur at all; potential adverse reactions or changes to business or employee relationships, including those
resulting from the announcement or completion of the Proposed Transaction; the parties do not receive regulatory approval of the Proposed Transaction; the occurrence
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