| SC 13G/A | 2014-11-10 | COHEN & STEERS INC | CORPORATE OFFICE PROPERTIES TRUST | 5,131,598 | 5.6% | EDGAR |
| SC 13G/A | 2014-02-14 | COHEN & STEERS INC | CORPORATE OFFICE PROPERTIES TRUST | 13,089,689 | 15.0% | EDGAR |
| SC 13G/A | 2014-02-12 | VANGUARD GROUP INC | CORPORATE OFFICE PROPERTIES TRUST | 10,910,130 | 12.5% | EDGAR |
| SC 13G/A | 2014-02-07 | APG Asset Management US Inc. | CORPORATE OFFICE PROPERTIES TRUST | 9,079,562 | 10.4% | EDGAR |
| SC 13G/A | 2014-02-07 | APG Group | CORPORATE OFFICE PROPERTIES TRUST | 9,079,562 | 10.4% | EDGAR |
| SC 13G/A | 2014-02-04 | VANGUARD SPECIALIZED FUNDS | CORPORATE OFFICE PROPERTIES TRUST | 5,913,494 | 6.8% | EDGAR |
| SC 13G/A | 2014-01-10 | BlackRock Inc. | CORPORATE OFFICE PROPERTIES TRUST | 8,874,423 | 10.2% | EDGAR |
| SC 13G/A | 2013-12-10 | BlackRock Inc. | CORPORATE OFFICE PROPERTIES TRUST | 8,747,410 | 10.0% | EDGAR |
| SC 13G/A | 2013-02-14 | VANGUARD SPECIALIZED FUNDS | CORPORATE OFFICE PROPERTIES TRUST | 5,273,696 | 6.5% | EDGAR |
| SC 13G/A | 2013-02-14 | COHEN & STEERS INC | CORPORATE OFFICE PROPERTIES TRUST | 10,451,336 | 12.9% | EDGAR |
| SC 13G | 2013-02-13 | Sumitomo Mitsui Trust Holdings, Inc. | CORPORATE OFFICE PROPERTIES TRUST | 2,343,833 | 2.9% | EDGAR |
| SC 13G | 2013-02-13 | LASALLE INVESTMENT MANAGEMENT SECURITIES LP | CORPORATE OFFICE PROPERTIES TRUST | 152,291 | 0.2% | EDGAR |
| SC 13G | 2013-02-12 | APG Asset Management US Inc. | CORPORATE OFFICE PROPERTIES TRUST | 9,395,198 | 11.6% | EDGAR |
| SC 13G | 2013-02-12 | APG Group | CORPORATE OFFICE PROPERTIES TRUST | 9,395,198 | 11.6% | EDGAR |
| SC 13G/A | 2013-02-11 | VANGUARD GROUP INC | CORPORATE OFFICE PROPERTIES TRUST | 9,716,504 | 12.0% | EDGAR |
| SC 13G/A | 2013-02-08 | SECURITY CAPITAL RESEARCH & MANAGEMENT INC | CORPORATE OFFICE PROPERTIES TRUST | 0 | 0.0% | EDGAR |
| SC 13G/A | 2013-01-31 | BlackRock Inc. | CORPORATE OFFICE PROPERTIES TRUST | 7,423,178 | 9.2% | EDGAR |
| SC 13G/A | 2013-01-30 | VANGUARD SPECIALIZED FUNDS | CORPORATE OFFICE PROPERTIES TRUST | 5,273,696 | 6.5% | EDGAR |
| SC 13G | 2012-10-15 | APG Asset Management US Inc. | CORPORATE OFFICE PROPERTIES TRUST | 7,236,957 | 10.0% | EDGAR |
| SC 13G | 2012-05-10 | COHEN & STEERS INC | CORPORATE OFFICE PROPERTIES TRUST | 8,112,994 | 11.3% | EDGAR |