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Exhibit 10.1    
    


 
 

Twelfth Amendment
  To
  Second Amended and Restated
  Limited Partnership Agreement
  Of
  Corporate Office Properties, L.P.    
    


        This Twelfth 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 2, 2003, 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 (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/  ROGER A. WAESCHE, JR.      
 Roger A. Waesche, Jr.
 Senior Vice President







 
 

Schedule of Partners    
    



	General Partner
 
	 	Partnership Units

	Corporate Office Properties Trust	 	27,082,879
	
Limited Partners and Preferred Limited Partners
	
 	

 
	Jay H. Shidler	 	452,878
	Shidler Equities, L.P.	 	2,995,439
	Clay W. Hamlin, III	 	568,492
	LBCW Limited Partnership	 	3,161,427
	Robert L. Denton	 	434,910
	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
	Henry D. Bullock	 	76,533
	Frederick K. Ito Trust	 	29,140
	June Y. I. Ito Trust	 	29,135
	RP Investments, LLC	 	268,671
	Denise J. Liszewski	 	34,333
	Samuel Tang	 	22,889
	Lawrence J. Taff	 	13,733
	Kimberly F. Acquino	 	5,874
	M.O.R. XXIX Associates Limited Partnership	 	148,381
	M.O.R. 44 Gateway Associates Limited Partnership	 	1
	John Parsinen	 	90,000
	M.O.R. Commons Limited Partnership	 	7
	John Edward De Burgh Blockey and Sanda Juanita Blockey	 	50,476
	Anthony Muscatello	 	90,905
	Lynn Hamlin	 	121,411
	 	 	36,029,748
	 	 	









 
 

EXHIBIT 1    
    
    Addendum    
    



	Series

Preferred

Units
 
	 	Preferred

Limited Partner
	 	No. of

Preferred

Units
	 	Liquidation

Preference

Per Preferred

Unit
	 	Priority

Percentage

Return*
	 	Priority
	 	Conversion

Factor
	 	Conversion

Commencement

Date

	B	 	General Partner	 	1,250,000	 	$	25	 	2.50	%	Senior	 	None	 	N/A
	C	 	UPG	 	1,016,662	 	$	25	 	**	 	Senior	 	2.381	 	12/22/2000
	D	 	General Partner	 	544,000	 	$	25	 	1.00	%	Senior	 	***	 	***
	E	 	General Partner	 	1,150,000	 	$	25	 	2.5625	%	Senior	 	None	 	N/A
	F	 	General Partner	 	1,425,000	 	$	25	 	 	 	Senior	 	None	 	N/A






	*
	Priority
Return Percentage is expressed as a percentage of the Liquidation Preference per Distribution Period. See the Agreement for the
definitions of "Priority Return Percentage," "Liquidation Preference" and "Distribution Period."



	**
	Priority
Percentage Return for the Series C Preferred Units shall be: 



2.25%
from December 21, 1999 to December 20, 2009; 2.625% from December 21, 2009 to December 20, 2014; and 3.00% thereafter. 



The
Distribution Period for the Series C Preferred Units shall be each calendar quarter ending March 31, June 30, September 30 and December 31 of each year. 



	***
	With
respect to any series of Preferred Units issued to the General Partner pursuant to Section 4.2(B) of the Agreement, the Conversion Commencement Date and the applicable
Conversion Factor shall correspond to the conversion commencement date and conversion factor of the related issuance of securities by the General Partner as provided in Section 4.2(B) of the
Agreement. See Section 9.8(A)(1) of the Agreement. 









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Exhibit 10.1


Twelfth Amendment To Second Amended and Restated Limited Partnership Agreement Of Corporate Office Properties, L.P.

Schedule of Partners

EXHIBIT 1 Addendum