<SEC-DOCUMENT>0000353480-17-000321-index.html : 20170123
<SEC-HEADER>0000353480-17-000321.hdr.sgml : 20170123
<ACCEPTANCE-DATETIME>20170123141759
ACCESSION NUMBER:		0000353480-17-000321
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20170123
DATE AS OF CHANGE:		20170123

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CORPORATE OFFICE PROPERTIES TRUST
		CENTRAL INDEX KEY:			0000860546
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				232947217
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-51779
		FILM NUMBER:		17540692

	BUSINESS ADDRESS:	
		STREET 1:		6711 COLUMBIA GATEWAY DRIVE
		STREET 2:		SUITE 300
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
		BUSINESS PHONE:		4432855400

	MAIL ADDRESS:	
		STREET 1:		6711 COLUMBIA GATEWAY DRIVE
		STREET 2:		SUITE 300
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CORPORATE OFFICE PROPERTIES TRUST INC
		DATE OF NAME CHANGE:	19980105

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ROYALE INVESTMENTS INC
		DATE OF NAME CHANGE:	19930328

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ROYALE REIT INC
		DATE OF NAME CHANGE:	19600201

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BlackRock Inc.
		CENTRAL INDEX KEY:			0001364742
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				320174431
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		55 EAST 52ND STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10055
		BUSINESS PHONE:		212-810-5300

	MAIL ADDRESS:	
		STREET 1:		55 EAST 52ND STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10055

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BlackRock, Inc.
		DATE OF NAME CHANGE:	20060929

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	New BlackRock, Inc.
		DATE OF NAME CHANGE:	20060601
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>corporate.office.p.txt
<TEXT>
Document 1 - file: corporate.office.p.txt

</DOCUMENT>
</SEC-DOCUMENT>