Exhibit 10.1

TWENTIETH AMENDMENT
TO
SECOND AMENDED AND RESTATED
LIMITED PARTNERSHIP AGREEMENT
OF
CORPORATE OFFICE PROPERTIES, L.P.

This Twentieth Amendment (the Amendment) to the Second Amended and Restated
Limited Partnership Agreement Of Corporate Office Properties, L.P., a Delaware
limited partnership (the Partnership), is made and entered into as of June 29th,
2006, by the undersigned.

RECITALS

A.            The Partnership is a limited partnership organized under the
Delaware Revised Uniform Limited Partnership Act and governed by that certain
Second Amended and Restated Limited Partnership Agreement dated as of
December 7, 1999, as amended to the date hereof (as amended, the “Partnership
Agreement”).

B.            The sole general partner of the Partnership is Corporate Office
Properties Trust, a real estate investment trust formed under the laws of the
State of Maryland (the “General Partner”).

C.            Pursuant to Section 11.1 (B) (iii), the General Partner desires to
amend the Partnership Agreement to reflect the admission, substitution,
termination and/or withdrawal of various limited partners in accordance with the
terms of the Partnership Agreement.

NOW THEREFORE, the General Partner, intending to be legally bound, hereby amends
the Partnership Agreement as follows, effective as of the date first set forth
above.

1.                                       Exhibit 1, Schedule of Partners, as
attached hereto and by this reference made a part hereof, is hereby substituted
for and intended to replace any prior Exhibit 1 attached to a prior Amendment to
the Partnership Agreement, and as attached hereto shall be a full and complete
listing of all the general and limited partners of the Partnership as of the
date of this Amendment, same being intended and hereby superceding all prior
Exhibit 1 listings.

In Witness Whereof, the General Partner has executed this Amendment as of the
day and year first above written.

 

Corporate Office Properties Trust, a

 

Maryland Real Estate Investment Trust

 

 

 

 

 

By:

/s/ Randall M. Griffin

 

Randall M. Griffin

 

President and Chief Executive Officer

 

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SCHEDULE OF PARTNERS

General Partner

 

Common
Units
of
Partnership
Units

 

Series E
Preferred
Units

 

Series F 
Preferred
Units

 

Series G
Preferred
Units

 

Series H
Preferred
Units

 

Series I
Preferred
Units

 

Corporate Office Properties Trust

 

40,301,869

 

1,150,000

 

1,425,000

 

2,200,000

 

2,000,000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Limited Partners and Preferred Limited Partners

 

 

 

 

 

 

 

 

 

 

 

 

 

Jay H. Shidler

 

452,878

 

 

 

 

 

 

 

 

 

 

 

Shidler Equities, L.P.

 

2,995,439

 

 

 

 

 

 

 

 

 

 

 

Clay W. Hamlin, III

 

562,767

 

 

 

 

 

 

 

 

 

 

 

LBCW Limited Partnership

 

2,831,107

 

 

 

 

 

 

 

 

 

 

 

Robert L. Denton

 

414,910

 

 

 

 

 

 

 

 

 

 

 

James K. Davis

 

51,589

 

 

 

 

 

 

 

 

 

 

 

John E. De B. Blockey, Trustee of the John E. de B. Blockey Living Trust dated
9/12/88

 

300,625

 

 

 

 

 

 

 

 

 

 

 

Frederick K. Ito Trust

 

20,340

 

 

 

 

 

 

 

 

 

 

 

June Y. I. Ito Trust

 

20,335

 

 

 

 

 

 

 

 

 

 

 

RP Investments, LLC

 

150,000

 

 

 

 

 

 

 

 

 

 

 

Denise J. Liszewski

 

23,333

 

 

 

 

 

 

 

 

 

 

 

Samuel Tang

 

4,389

 

 

 

 

 

 

 

 

 

 

 

Lawrence J. Taff

 

13,733

 

 

 

 

 

 

 

 

 

 

 

Kimberly F. Aquino

 

2,937

 

 

 

 

 

 

 

 

 

 

 

M.O.R. XXIX Associates Limited Partnership

 

148,381

 

 

 

 

 

 

 

 

 

 

 

M.O.R. 44 Gateway Associates Limited Partnership

 

1

 

 

 

 

 

 

 

 

 

 

 

John Parsinen

 

66,000

 

 

 

 

 

 

 

 

 

 

 

M.O.R. Commons Limited Partnership

 

7

 

 

 

 

 

 

 

 

 

 

 

John Edward De Burgh Blockey and Sanda Juanita Blockey

 

10,476

 

 

 

 

 

 

 

 

 

 

 

Lynn Hamlin

 

121,411

 

 

 

 

 

 

 

 

 

 

 

Housing Affiliates, Inc.

 

4,402

 

 

 

 

 

 

 

 

 

 

 

Reingle Corp.

 

730

 

 

 

 

 

 

 

 

 

 

 

Joseph Tawil

 

2,160

 

 

 

 

 

 

 

 

 

 

 

The Lovejoy Trust

 

59,528

 

 

 

 

 

 

 

 

 

 

 

The Century Trust

 

59,528

 

 

 

 

 

 

 

 

 

 

 

A. Charles Wilson & Betty S. Wilson Trust

 

5,908

 

 

 

 

 

 

 

 

 

 

 

Harold & Renee Holland

 

4,320

 

 

 

 

 

 

 

 

 

 

 

Irwin Hoffman

 

1,880

 

 

 

 

 

 

 

 

 

 

 

Rouse 1988 Trust

 

2,160

 

 

 

 

 

 

 

 

 

 

 

CB Management, L.L.C.

 

2,497

 

 

 

 

 

 

 

 

 

 

 

Patriot Partner, L.L.C.

 

80,000

 

 

 

 

 

 

 

 

 

 

 

National Prostate Cancer Coalition

 

200

 

 

 

 

 

 

 

 

 

 

 

John A. Luetkemeyer, Jr.

 

38,954

 

 

 

 

 

 

 

 

 

 

 

Eugene H. Schreiber and Richard E. Levine, Trustees U/A Sarah R. Schapiro dated
3/2/76 (Trust 113)

 

38,954

 

 

 

 

 

 

 

 

 

 

 

Eugene H. Schreiber and Richard E. Levine, Trustees U/A J. Mark Schapiro dated
3/27/02 f/b/o J.M. Schapiro (Trust 159)

 

10,114

 

 

 

 

 

 

 

 

 

 

 

Lawrence G. Rief

 

2,526

 

 

 

 

 

 

 

 

 

 

 

Thomas F. Mullan III

 

58,857

 

 

 

 

 

 

 

 

 

 

 

Erin L. Mullan

 

9,055

 

 

 

 

 

 

 

 

 

 

 

Norman W. Wilder

 

22,637

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TRC Associates Limited Partnership

 

 

 

 

 

 

 

 

 

 

 

352,000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

48,896,937

 

1,150,000

 

1,425,000

 

2,200,000

 

2,000,000

 

352,000

 

 

 

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