MPT OF OGDEN, LLC, MPT OF LITTLE ELM FCER, LLC and MPT OF BRODIE FCER, LLC, asGuarantors, MPT OPERATING PARTNERSHIP, L.P. and MPT FINANCE CORPORATION, as Issuers, MEDICAL PROPERTIESTRUST, INC., as Parent and a Guarantor, the other GUARANTORS named herein, as Guarantors, and WILMINGTON TRUST COMPANY, asTrustee TWELFTH SUPPLEMENTAL INDENTURE Dated as of October 30, 2013 To INDENTURE Dated as of April 26, 2011 6.875% Senior Notes due 2021 TWELFTH SUPPLEMENTAL INDENTURE

Exhibit 4.15

MPT OF OGDEN, LLC,

MPT OF LITTLE ELM FCER, LLC

and

MPT OF BRODIE FCER, LLC,

as Guarantors,

MPT OPERATING PARTNERSHIP, L.P.

and

MPT FINANCE CORPORATION,

as Issuers,

MEDICAL PROPERTIES TRUST, INC.,

as Parent and a Guarantor,

the other GUARANTORS named herein,

as Guarantors,

and

WILMINGTON TRUST COMPANY,

as Trustee

TWELFTH SUPPLEMENTAL INDENTURE

Dated as of October 30, 2013

To

INDENTURE

Dated as of April 26, 2011

6.875% Senior Notes due 2021

TWELFTH SUPPLEMENTAL INDENTURE

TWELFTH SUPPLEMENTAL INDENTURE (this “Twelfth Supplemental Indenture”), dated as of October 30, 2013, by and among MPT of Ogden, LLC, a Delaware limited liability company, MPT of Little Elm FCER, LLC, a Delaware limited liability company, and MPT of Brodie FCER, LLC, a Delaware limited liability company (the “New Guaranteeing Subsidiaries”), MPT Operating Partnership, L.P., a Delaware limited partnership (“Opco”), MPT Finance Corporation, a Delaware corporation (“Finco” and, together with Opco, the “Issuers”), Medical Properties Trust, Inc., a Maryland corporation (the “Parent”), as Guarantor, each of the other Guarantors (as defined in the Indenture), as Guarantors, and Wilmington Trust Company, a Delaware chartered trust company, as Trustee (the “Trustee”).

WITNESSETH

WHEREAS, the Issuers and the Guarantors have heretofore executed and delivered an Indenture, dated as of April 26, 2011 (the “Base Indenture”), as supplemented by that certain First Supplemental Indenture, dated as of August 10, 2011 (the “First Supplemental Indenture”), by that certain Second Supplemental Indenture, dated as of October 3, 2011 (the “Second Supplemental Indenture”), by that certain Third Supplemental Indenture, dated as of December 2, 2011 (the “Third Supplemental Indenture”), by that certain Fourth Supplemental Indenture, dated as of January 19, 2012 (the “Fourth Supplemental Indenture”), by that certain Fifth Supplemental Indenture dated as of April 9, 2012, (the “Fifth Supplemental Indenture”), by that certain Sixth Supplemental Indenture dated as of June 27, 2012, (the “Sixth Supplemental Indenture”), by that certain Seventh Supplemental Indenture dated as of July 31, 2012 (the “Seventh Supplemental Indenture”), by that certain Eighth Supplemental Indenture dated as of September 28, 2012 (the “Eighth Supplemental Indenture”), by that certain Ninth Supplement Indenture dated as of December 28, 2012 (the “Ninth Supplemental Indenture”), by that certain Tenth Supplement Indenture dated as of June 27, 2013 (the “Tenth Supplemental Indenture”), and by that certain Eleventh Supplemental Indenture dated as of August 8, 2013 (the “Eleventh Supplemental Indenture,” together with the Base Indenture, the First Supplemental Indenture, the Second Supplemental Indenture, the Third Supplemental Indenture, the Fourth Supplemental Indenture, the Fifth Supplemental Indenture, the Sixth Supplemental Indenture, the Seventh Supplemental Indenture, the Eighth Supplemental Indenture, the Ninth Supplemental Indenture and the Tenth Supplemental Indenture the “Indenture”), providing for the issuance by the Issuers of the 6.875% Senior Notes due 2021 (the “Notes”);

WHEREAS, pursuant to Section 9.01(a)(4) of the Indenture, the Issuers, the Guarantors and the Trustee may supplement the Indenture without the consent of any Holders in order to add Guarantees with respect to the Notes;

WHEREAS, as of October 30, 2013, the New Guaranteeing Subsidiaries guarantee the Credit Agreement, and pursuant to Section 4.14(a) of the Indenture, the New Guaranteeing Subsidiaries are required to become Guarantors under the Indenture;

WHEREAS, the Indenture requires that an entity that constitutes a Guarantor shall join the Issuers and the existing Guarantors in executing and delivering to the Trustee a supplemental

indenture pursuant to which such entity shall unconditionally Guarantee, on a joint and several basis, the full and prompt payment of the principal of, premium, if any, and interest in respect of the Notes on a senior basis and all other obligations under the Indenture;

WHEREAS, in the Fifth Supplemental Indenture and continuing thereafter, the name of the Trustee was mistakenly changed to Wilmington Trust, National Association and the parties hereto desire to correct the Indenture to make clear that Wilmington Trust Company is the Trustee under the Indenture; and

WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is authorized to execute and deliver this Twelfth Supplemental Indenture.

NOW, THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Issuers, the Guarantors, the Trustee and the New Guaranteeing Subsidiaries mutually covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

1. CAPITALIZED TERMS. Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture. The rules of interpretation set forth in the Indenture shall be applied here as if set forth in full herein.

2. AGREEMENT TO GUARANTEE. The New Guaranteeing Subsidiaries hereby agree to provide unconditional Guarantees on the terms and subject to the conditions set forth in the Indenture including but not limited to Article 10 thereof.

3. CORRECTION OF SUPPLEMENTAL INDENTURES. The name of the Trustee in the Fifth Supplemental Indenture, Sixth Supplemental Indenture, Seventh Supplemental Indenture, Eighth Supplemental Indenture, Ninth Supplemental Indenture, Tenth Supplemental Indenture and Eleventh Supplemental Indenture is hereby corrected to “Wilmington Trust Company”. To the extent necessary, the Trustee, along with the Issuers and Guarantors, hereby ratify each of the foregoing Supplemental Indentures effective as of the dates entered into and acknowledge and agree that the Indenture, as amended and supplemented from time to time, is between the Issuers, applicable Guarantors signatories thereto, and Wilmington Trust Company, as Trustee and not Wilmington Trust, National Association.

3. MISCELLANEOUS PROVISIONS.

(a) The Trustee makes no undertaking or representation in respect of, and shall not be responsible in any manner whatsoever for and in respect of, the validity or sufficiency of this Twelfth Supplemental Indenture or the proper authorization or the due execution hereof by the Issuers or for or in respect of the recitals and statements contained herein, all of which recitals and statements are made solely by the Issuers.

(b) On the date hereof, the Indenture shall be supplemented and amended in accordance herewith, and this Twelfth Supplemental Indenture shall form part of the Indenture for all purposes, and the Holder of every Note heretofore or hereafter authenticated and delivered under the Indenture shall be bound thereby. The Trustee accepts the trusts created by the Indenture, as amended and supplemented by this Twelfth Supplemental Indenture, and agrees to perform the same upon the terms and conditions of the Indenture, as amended and supplemented by this Twelfth Supplemental Indenture.

(c) This Twelfth Supplemental Indenture shall be deemed to be incorporated in, and made a part of, the Indenture. The Indenture, as amended and supplemented by this Twelfth Supplemental Indenture, shall be read, taken and construed as one and the same instrument and all the provisions of the Indenture shall remain in full force and effect in accordance with the terms thereof and as amended and supplemented by this Twelfth Supplemental Indenture.

(d) THIS TWELFTH SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

IN WITNESS WHEREOF, the parties hereto have caused this Twelfth Supplemental Indenture to be duly executed and attested, all as of the date first above written.

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