COPT DEFENSE PROPERTIES — Director's Dealing 2011

Jun 15, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CORPORATE OFFICE PROPERTIES TRUST (OFC)
CIK: 0000860546
Period of Report: 2011-06-13

Reporting Person: GRIFFIN RANDALL M (Director, Chief Executive Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-06-13	Common Shares	P	3000	$31.5606	Acquired	429956	Direct

Footnotes

F1: Common share holdings comprised of 95,888 owned by RMG Security Trust, 2,000 owned by Rand Griffin Non-qualified 401K plan, 201,893 unrestricted and 130,175 restricted.

F2: Weighted average sale price. Sale prices ranged from $31.5317-$31.5750. The reporting person hereby undertakes to supply the Staff, the Issuer, or a security holder of the Issuer with full information regarding the reported transactions