UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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 11, 2017 (December 8, 2017)

Arch Coal, Inc.

(Exact name of registrant as specified in its charter)

CityPlace One
One CityPlace Drive, Suite 300
St. Louis, Missouri 63141

(Address, including zip code, of principal executive offices)

Registrant’s telephone number, including area code: (314) 994-2700

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:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in 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 o

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. o

Item 1.01 Entry into a Material Definitive Agreement.

On December 8, 2017, Arch Coal, Inc. (the “Company”) entered into a stock repurchase agreement (the “Stock Repurchase Agreement”) with certain investment funds affiliated with Monarch Alternative Capital LP (collectively, “Monarch”), pursuant to which the Company agreed to repurchase from Monarch 500,000 shares of the Company’s common stock at a purchase price of $83.03 per share, representing aggregate consideration of approximately $41.5 million. The Company intends to fund the repurchase with cash on hand.  The share repurchase would be made pursuant to, and would count toward, the Company’s existing share repurchase program.

The transaction is expected to close on or about December 14, 2017, subject to customary closing conditions.

A copy of the Stock Repurchase Agreement has been attached as Exhibit 10.1 to this Current Report on Form 8-K and is incorporated by reference herein. The foregoing description of the Stock Repurchase Agreement does not purport to be complete and is qualified in its entirety by reference to such Exhibit.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

The following exhibits are attached hereto and filed herewith.

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Signatures

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

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