FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * HAMLIN CLAY W III   2. Issuer Name and Ticker or Trading Symbol CORPORATE OFFICE PROPERTIES TRUST [OFC] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 424 MULBERRY LANE 3. Date of Earliest Transaction (Month/Day/Year) 11/22/2005 (Street) HAVERFORD, PA 19041 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Units - COPLP 11/22/2005   D   3,375 D (1) 3,715,285 I See footnote (2) Common Units - COPLP 12/12/2005   C   150,000 D (3) 3,565,285 I See footnote (3) Common Shares - COPT 12/12/2005   A   150,000 A (4) 160,000 I See footnote (5) Common Shares - COPT 12/12/2005   D   37,500 D $ 36.58 122,500 I See footnote (6) Common Shares - COPT 12/13/2005   D   37,500 D $ 36.3 85,000 I See footnote (7)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
HAMLIN CLAY W III 424 MULBERRY LANE HAVERFORD, PA 19041	X

Signatures

Karen M. Singer, by Power of Attorney		12/14/2005
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Total Gift 3,375 Common Units of Corporate Office Properties, L.P. to the following organizatins: 325 Units to The Nichols School, 200 units to Johns Hopkins University, 750 units to University of Pennsylvania, Friends of Penn Tennis, 200 units to National Prostate Cancer Coalition, 500 units to Episcopal Academy, 100 units to Bryn Mawr Presbyterian Churth, 350 units to Arthur Ashe Youth Tennis & Education, 200 units to Heritage Foundation, and 750 units to Volunteers in Medicine.
(2)	As of 11/22/05, COPLP Units owned as follows: 3,031,107 owned by LBCW Limited Partnership, 562,767 owned directly by Clay Hamlin, 121,411 owned by Lynn Hamlin
(3)	As of 12/12/05, COPLP Units owned as follows: 2,881,107 owned by LBCW Limited Partnership, 562,767 owned by Clay, 121,411 owned by Lynn Hamlin
(4)	Acquired through Conversion of COPLP Units
(5)	10,000 Common Shares held in IRA, 150,000 Owned by LBCW Limited Partnership
(6)	10,000 Common Shares held in IRA, 112,500 Owned by LBCW Limited Partnership
(7)	10,000 Common Shares held in IRA, 75,000 Owned by LBCW Limited Partnership

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