Ownership Submission
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)
12/12/2005
(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 12/15/2006   G   72,850 D (1) 3,442,435 I See footnote (2)
Common Units - COPLP 01/23/2007   G   70,000 D (3) 3,442,435 I See footnote (3)

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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   01/23/2007
**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 Direct and Indirect Gift 72,850 Common Units of Corporate Office Properties, L.P. to the following organizatins: (i) 70,000 Common Units from Lynn Hamlin to Univ of PA Friends of Penn Tennis, (ii) 2,850 Common Units from Clay Hamlin to the following charities in the amounts indicated--The Nichols School (300 units), Johns Hopkins Univ (200 units), Univ of PA Friends of Penn Tennnis (500 units), National Prostate Cancer Coalition (200 units),Episcopal Academy (500 units), Bryn Mawr Presbyterian Church (150 units), Arthur Ashe Youth Tennnis & Education (300 units), Heritage Foundation (200 units), Volunteers in Medicine (500 units).
(2) As of 12/15/06, COPLP Units owned as follows: 2,831,107 owned by LBCW Limited Partnership, 559,917 owned by Clay Hamlin, 51,411 owned by Lynn Hamlin
(3) As of 1/23/07, Clay W. Hamlin, III transferred 70,000 COPLP Units to his wife, Lynn B. Hamlin and the COPLP Units are now owned as follows: 2,831,107 owned by LBCW Limited Partnership, 489,917 owned by Clay Hamlin, 121,411 owned by Lynn Hamlin

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