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COLUMBIA, Md.--([ BUSINESS WIRE ])--Corporate Office Properties Trust (COPT) (NYSE: OFC), a specialty office real estate investment trust (REIT) that focuses primarily on serving the specialized requirements of U.S. Government and Defense Information Technology tenants, reiterates the date and time for its year end 2011 conference call and announces the dates and times for its 2012 quarterly conference calls. The scheduled dates and times for these calls are as follows:

Please use the following link to pre-register and view important information about this conference call. Pre-registering is not mandatory but is recommended as it will provide you immediate entry into the call and will facilitate the timely start of the conference. Pre-registration only takes a few moments and you may pre-register at anytime, including up to and after the call start time. To pre-register, please click on the below link:
[ https://www.theconferencingservice.com/prereg/key.process?key=PVEJ63YG9 ]

You may also pre-register in the Investor Relations section of the Companyas website at [ www.copt.com ]. Alternatively, you may be placed into the call by an operator by calling the number provided above at least 5 to 10 minutes before the start of the call. A replay of this call will be available beginning Thursday, February 9 at 2:00 p.m. Eastern Time through Thursday, February 23 at midnight Eastern Time. To access the replay within the United States, please call 888-286-8010 and use passcode 81352459. To access the replay outside the United States, please call 617-801-6888 and use passcode 81352459.

The conference calls will also be available via live webcast in the Investor Relations section of the Companyas website at [ www.copt.com ]. A replay of the conference calls will be immediately available via webcast in the Investor Relations section of the Companyas website.

Please use the following link to pre-register and view important information about this conference call. Pre-registering is not mandatory but is recommended as it will provide you immediate entry into the call and will facilitate the timely start of the conference. Pre-registration only takes a few moments and you may pre-register at anytime, including up to and after the call start time. To pre-register, please click on the below link:
[ https://www.theconferencingservice.com/prereg/key.process?key=PJAUAWVD7 ]

You may also pre-register in the Investor Relations section of the Companyas website at [ www.copt.com ]. Alternatively, you may be placed into the call by an operator by calling the number provided above at least 5 to 10 minutes before the start of the call. A replay of this call will be available beginning Thursday, April 26 at 3:00 p.m. Eastern Time through Thursday, May 10 at midnight Eastern Time. To access the replay within the United States, please call 888-286-8010 and use passcode 94646315. To access the replay outside the United States, please call 617-801-6888 and use passcode 94646315.

The conference calls will also be available via live webcast in the Investor Relations section of the Companyas website at [ www.copt.com ]. A replay of the conference calls will be immediately available via webcast in the Investor Relations section of the Companyas website.

Please use the following link to pre-register and view important information about this conference call. Pre-registering is not mandatory but is recommended as it will provide you immediate entry into the call and will facilitate the timely start of the conference. Pre-registration only takes a few moments and you may pre-register at anytime, including up to and after the call start time. To pre-register, please click on the below link:
[ https://www.theconferencingservice.com/prereg/key.process?key=PAVMDVEGC ]

You may also pre-register in the Investor Relations section of the Companyas website at [ www.copt.com ]. Alternatively, you may be placed into the call by an operator by calling the number provided above at least 5 to 10 minutes before the start of the call. A replay of this call will be available beginning Thursday, July 26 at 3:00 p.m. Eastern Time through Thursday, August 9 at midnight Eastern Time. To access the replay within the United States, please call 888-286-8010 and use passcode 58125347. To access the replay outside the United States, please call 617-801-6888 and use passcode 58125347.

The conference calls will also be available via live webcast in the Investor Relations section of the Companyas website at [ www.copt.com ]. A replay of the conference calls will be immediately available via webcast in the Investor Relations section of the Companyas website.

Please use the following link to pre-register and view important information about this conference call. Pre-registering is not mandatory but is recommended as it will provide you immediate entry into the call and will facilitate the timely start of the conference. Pre-registration only takes a few moments and you may pre-register at anytime, including up to and after the call start time. To pre-register, please click on the below link:
[ https://www.theconferencingservice.com/prereg/key.process?key=PQFR39JDX ]

You may also pre-register in the Investor Relations section of the Companyas website at [ www.copt.com ]. Alternatively, you may be placed into the call by an operator by calling the number provided above at least 5 to 10 minutes before the start of the call. A replay of this call will be available beginning Thursday, October 25 at 3:00 p.m. Eastern Time through Thursday, November 8 at midnight Eastern Time. To access the replay within the United States, please call 888-286-8010 and use passcode 51365923. To access the replay outside the United States, please call 617-801-6888 and use passcode 51365923.

The conference calls will also be available via live webcast in the Investor Relations section of the Companyas website at [ www.copt.com ]. A replay of the conference calls will be immediately available via webcast in the Investor Relations section of the Companyas website.

Company Information

Corporate Office Properties Trust (COPT) (NYSE: OFC) is a specialty office real estate investment trust (REIT) that focuses primarily on strategic customer relationships and specialized tenant requirements in the U.S. Government and Defense Information Technology sectors and Data Centers serving such sectors. The Company acquires, develops, manages and leases office and data center properties that are typically concentrated in large office parks primarily located adjacent to government demand drivers and/or in strong markets that we believe possess growth opportunities. As of September 30, 2011, the Company owned 266 office properties totaling 21.3million rentable square feet, which includes 20 properties totaling 1.1 million square feet held through joint ventures. The Companyas portfolio primarily consists of technically sophisticated buildings in visually appealing settings that are environmentally sensitive, sustainable and meet unique customer requirements. COPT is an S&P MidCap 400 company and more information can be found at [ www.copt.com ].

Forward-Looking Information

This press release may contain aforward-lookinga statements, as defined in Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, that are based on the Companyas current expectations, estimates and projections about future events and financial trends affecting the Company.Forward-looking statements can be identified by the use of words such as amay,a awill,a ashould,a acould,a abelieve,a aanticipate,a aexpect,a aestimate,a aplana or other comparable terminology.Forward-looking statements are inherently subject to risks and uncertainties, many of which the Company cannot predict with accuracy and some of which the Company might not even anticipate.Accordingly, the Company can give no assurance that these expectations, estimates and projections will be achieved.Future events and actual results may differ materially from those discussed in the forward-looking statements.

Important factors that may affect these expectations, estimates, and projections include, but are not limited to:

• general economic and business conditions, which will, among other things, affect office property demand and rents, tenant creditworthiness, interest rates and financing availability;
• adverse changes in the real estate markets including, among other things, increased competition with other companies;
• the Companyas ability to borrow on favorable terms;
• risks of real estate acquisition and development activities, including, among other things, risks that development projects may not be completed on schedule, that tenants may not take occupancy or pay rent or that development or operating costs may be greater than anticipated;
• risks of investing through joint venture structures, including risks that the Companyas joint venture partners may not fulfill their financial obligations as investors or may take actions that are inconsistent with the Companyas objectives;
• changes in our plans or views of market economic conditions or failure to obtain development rights, either of which could result in recognition of impairment losses;
• our ability to satisfy and operate effectively under Federal income tax rules relating to real estate investment trusts and partnerships;
• governmental actions and initiatives, including risks associated with the impact of a government shutdown such as a reduction in rental revenues or non-renewal of leases;
• the dilutive effect of issuing additional common shares; and
• environmental requirements.

The Company undertakes no obligation to update or supplement any forward-looking statements. For further information, please refer to the Companyas filings with the Securities and Exchange Commission, particularly the section entitled aRisk Factorsa in Item 1A of the Companyas Annual Report on Form 10-K for the year ended December 31, 2010.