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): March 21, 2016

MEDICAL PROPERTIES TRUST, INC.

MPT OPERATING PARTNERSHIP, L.P.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (205) 969-3755

N/A

(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:

On March 22, 2016, Medical Properties Trust, Inc. (the “Company” or “MPT”) issued a press release announcing the pending RegionalCare/Capella merger and related transactions, as described below under Item 8.01. A copy of the press release is furnished as Exhibit 99.1 hereto and incorporated herein by reference.

The information contained in this Item 7.01 is being “furnished” and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise. The information in this Item 7.01, including referenced materials posted to the Company’s website, shall not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933, as amended, or into any filing or other document pursuant to the Securities Exchange Act of 1934, as amended, except as otherwise expressly stated in any such filing.

On March 21, 2016, MPT and its affiliates entered into definitive agreements with RegionalCare Hospital Partners, Inc. (“RegionalCare”), an affiliate of certain funds managed by affiliates of Apollo Global Management, LLC (together with its consolidated subsidiaries, “Apollo”), under which MPT’s investment in the operations of Capella Healthcare, Inc. (“Capella”) will be merged with and into RegionalCare.

MPT is expected to receive net proceeds of approximately $550 million from this transaction. Under the terms of the agreements, MPT will receive approximately $390 million for its equity investment and loans made as part of the Capella transaction that closed on August 31, 2015. In addition, MPT will receive $210 million in prepayment of two mortgage loans for hospitals in Russellville, Arkansas, and Lawton, Oklahoma, that MPT made to subsidiaries of Capella in connection with the Capella transaction on August 31, 2015. The Company will retain an approximate $100 million loan for a hospital property in Olympia, Washington, that is expected to be converted to a sale and leaseback arrangement upon regulatory approval. Additionally, the Company and an Apollo affiliate will each invest up to $50 million in unsecured senior notes to be issued by RegionalCare.

MPT will maintain its ownership of five Capella hospitals in Hot Springs, Arkansas; Camden, South Carolina; Hartsville, South Carolina; Muskogee, Oklahoma; and McMinnville, Oregon.

Closing of the transaction, which is subject to customary closing conditions, is expected during the 2016 second quarter.

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SIGNATURES

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

Date: March 25, 2016

Date: March 25, 2016