UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of Earliest Event Reported): December 13, 2018

EXPRESS SCRIPTS HOLDING COMPANY

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code 314-996-0900

Not Applicable

Former name or former address, if changed since last report

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

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

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 7.01 Regulation FD Disclosure.

As previously announced, on March 8, 2018, Express Scripts Holding Company, a Delaware corporation (“Express Scripts”), entered into an Agreement and Plan of Merger (as amended, the “Merger Agreement”) with Cigna Corporation (“Cigna”), Halfmoon Parent, Inc., a Delaware corporation and a direct wholly owned subsidiary of Cigna (“Holdco”), Halfmoon I, Inc., a Delaware corporation and a direct wholly owned subsidiary of Holdco, and Halfmoon II, Inc., a Delaware corporation and a direct wholly owned subsidiary of Holdco, pursuant to which, subject to the conditions of the Merger Agreement, Holdco will acquire Express Scripts in a cash and stock transaction.

On December 13, 2018, the State of New York determined that a previously noticed hearing in that State was not required and issued its approval of the transaction. Also on December 13, 2018, the State of California issued its approval of the transaction. We continue to work with regulators in New Jersey, the one outstanding state where approval is required, and continue to expect that the transaction will close by the end of 2018, subject to the satisfaction of all closing conditions.

The information contained in this Current Report on Form 8-K under Item 7.01, is being furnished pursuant to Item 7.01 of Form 8-K and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section. The information contained in this Current Report on Form 8-K under Item 7.01, shall not be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, except as shall be expressly set forth by specific reference in such a filing.

Cautionary Notes on Forward Looking Statements

This communication contains statements which, to the extent they are not statements of historical or present fact, constitute “forward-looking statements” under the securities laws. These forward-looking statements are intended to provide Cigna management’s and/or Express Scripts management’s current expectations or plans for future operating and financial performance, based on assumptions currently believed to be valid. Forward-looking statements can be identified by the use of words such as “believe,” “expect,” “expectations,” “plans,” “strategy,” “prospects,” “estimate,” “project,” “target,” “anticipate,” “will,” “may,” “should,” “see,” “guidance,” “confident” and other words of similar meaning in connection with a discussion of future operating or financial performance. Forward-looking statements may include, among other things, statements relating to future sales, earnings, cash flow, results of operations, uses of cash, share repurchases and other measures of financial performance or potential future plans, strategies or transactions of Cigna or the combined company following consummation of the mergers, the anticipated benefits of the mergers, including estimated synergies, the expected timing of completion of the mergers, Cigna’s ability to obtain financing for the mergers and other statements that are not historical facts. All forward-looking statements involve risks, uncertainties and other factors that may cause actual results to differ materially from those expressed or implied in the forward-looking statements. For those statements, Cigna and Express Scripts claim the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995. Risks, uncertainties and other factors that could cause actual results to differ from these forward-looking statements include, but are not limited to, risks and uncertainties detailed in Cigna’s and Express Scripts’ periodic public filings with the SEC, including those discussed in the section entitled “Risk Factors” of the registration statement and in the sections entitled “Risk Factors” in Cigna’s Annual Report on Form 10-K for the year ended December 31, 2017, Cigna’s Quarterly Report on Form 10-Q for the period ended June 30, 2018, Express Scripts’ Annual Report on Form 10-K for the year ended December 31, 2017 and Express Scripts’ Quarterly Report on Form 10-Q for the period ended June 30, 2018, factors contained or incorporated by reference into such documents and in subsequent filings by Cigna and Express Scripts, and the following factors:

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There can be no assurance that the mergers or any other transaction described in this Current Report on Form 8-K will in fact be completed in the manner described or at all. Any forward-looking statement speaks only as of the date on which it is made, and Cigna and Express Scripts assume no obligation to update or revise such statement, whether as a result of new information, future events or otherwise, except as required by applicable law. Readers are cautioned not to place undue reliance on any of these forward-looking statements.

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SIGNATURE

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

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