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): September 13, 2013

MEDICAL PROPERTIES TRUST, INC.

MPT OPERATING PARTNERSHIP, L.P.

(Exact Name of Registrant as Specified in Charter)

Commission File Number 001-32559

(205) 969-3755

(Registrant’s telephone number, including area code)

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:

Item 1.01. Entry into a Material Definitive Agreement.

On September 13, 2013, affiliates of Medical Properties Trust, Inc. (the “Company”) entered into an agreement to acquire 11 rehabilitation facilities in the Federal Republic of Germany from RHM Klinik-und Altenheimbetriebe GmbH & Co. KG (“RHM”) for an aggregate purchase price, including payment by the Company of approximately €9.0 million in applicable transfer taxes, of €184.0 million (plus a commitment to provide up to €10.0 million in financing for the construction of additions to the facilities within the next two years). Each of the facilities will be leased back to RHM under a master lease providing for a term of 27 years and for annual rent increases of 2.0 % from 2015 through 2017, and of 0.5 % thereafter. On December 31, 2020 and every three years thereafter rent will also be increased to reflect 70% of cumulative increases in the German consumer price index.

The table below sets forth pertinent details with respect to the eleven facilities to be acquired:

The acquisition is subject to customary real estate, regulatory and other closing conditions, including waiver of any statutory pre-emption rights by local municipalities. The agreement provides the parties with limited mutual termination rights, in whole or in part, in the event the conditions to closing are not satisfied. If the agreement is terminated in this case due to the default of one of the parties, the other party is entitled to liquidated damages of €3.0 million, plus notary and court costs, as its sole remedy.

The Company currently expects to consummate the acquisition during the fourth quarter of 2013.

Item 7.01. Regulation FD Disclosure.

On September 19, 2013, the Company issued a press release announcing the RHM acquisition, a copy of which is furnished as Exhibit 99.1 hereto and is incorporated herein by reference.

The information furnished pursuant to this Item 7.01 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liability of that section or Sections 11 and 12(a)(2) of the Securities Act if 1933, as amended.

In addition, this information shall not be deemed incorporated by reference in any filing of the Company with the Securities and Exchange Commission, except as expressly set forth by specific references in any such filing.

Item 9.01. Financial Statements and Exhibits.

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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 hereunto duly authorized.

Date: September 19, 2013

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INDEX TO EXHIBITS

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