AGREEMENT JOINT FILING OF SCHEDULE 13D

EXHIBIT 1

AGREEMENT

JOINT FILING OF SCHEDULE 13D

The undersigned hereby agree to jointly prepare and file with regulatory authorities this Schedule 13D and any future amendments thereto reporting each of the undersigned’s ownership of securities of CommonWealth REIT, and hereby affirm that such Schedule 13D is being filed on behalf of each of the undersigned pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning him or it contained therein, but shall not be responsible for the completeness and accuracy of the information concerning the other, except to the extent that he or it knows or has reason to believe that such information is inaccurate.

Date:		February 26, 2013		CORVEX MANAGEMENT LP
				By:		/s/ Xxxxx Xxxxxxx
						Xxxxx Xxxxxxx
						Managing Partner
Date:		February 26, 2013		XXXXX XXXXXXX
				By:		/s/ Xxxxx Xxxxxxx
Date:		February 26, 2013		RELATED FUND MANAGEMENT, LLC
				By:		/s/ Xxxxxxx X’Xxxxx
						Xxxxxxx X’Xxxxx
						Vice President
Date:		February 26, 2013		RELATED REAL ESTATE RECOVERY FUND GP-A, LLC
				By:		/s/ Xxxxxxx X’Xxxxx
						Xxxxxxx X’Xxxxx
						Vice President
Date:		February 26, 2013		RELATED REAL ESTATE RECOVERY FUND GP, L.P.
				By:		Related Real Estate Recovery Fund GP-A, LLC, its general partner
				By:		/s/ Xxxxxxx X’Xxxxx
						Xxxxxxx X’Xxxxx
						Vice President
Date:		February 26, 2013		RELATED REAL ESTATE RECOVERY FUND, L.P.
				By:		Related Real Estate Recovery Fund GP, L.P., its general partner
				By:		Related Real Estate Recovery Fund GP-A, LLC, its general partner
				By:		/s/ Xxxxxxx X’Xxxxx
						Xxxxxxx X’Xxxxx
						Vice President