Exhibit 4.2


 


THIS SECURITY IS A GLOBAL
SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS
REGISTERED IN THE NAME OF THE DEPOSITARY OR A NOMINEE OF THE DEPOSITARY, WHICH MAY BE
TREATED BY THE ISSUER, THE TRUSTEE AND ANY AGENT THEREOF AS OWNER AND HOLDER OF
THIS SECURITY FOR ALL PURPOSES.


 


UNLESS THIS CERTIFICATE IS
PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A
NEW YORK CORPORATION (“DTC”), TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE &
CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF
DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO
ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE &
CO., HAS AN INTEREST HEREIN.


 


UNLESS AND UNTIL IT IS
EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE REGISTERED FORM IN
THE LIMITED CIRCUMSTANCES REFERRED TO IN THE INDENTURE, THIS GLOBAL SECURITY MAY NOT
BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE
DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER
NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A
SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.


 


NEITHER THIS SECURITY NOR
THE COMMON SHARES OF BENEFICIAL INTEREST ISSUABLE ON EXCHANGE OF THIS SECURITY
HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES
ACT”), OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION.  NEITHER THIS SECURITY NOR THE COMMON SHARES
OF BENEFICIAL INTEREST ISSUABLE ON EXCHANGE OF THIS SECURITY, NOR ANY INTEREST
OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD, ASSIGNED,
TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF
SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO,
SUCH REGISTRATION.  THE HOLDER OF THIS
SECURITY, BY ITS ACCEPTANCE HEREOF, (1) REPRESENTS THAT IT IS A “QUALIFIED
INSTITUTIONAL BUYER” (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT (“RULE
144A”)); (2) AGREES ON ITS OWN BEHALF AND ON BEHALF OF ANY INVESTOR
ACCOUNT FOR WHICH IT HAS PURCHASED SECURITIES, TO OFFER, SELL OR OTHERWISE
TRANSFER THIS SECURITY OR ANY COMMON SHARES OF BENEFICIAL INTEREST ISSUABLE ON
EXCHANGE OF THIS SECURITY, PRIOR TO THE TIME AT WHICH THIS SECURITY MAY BE
RESOLD PURSUANT TO RULE 144 UNDER THE SECURITIES ACT (OR ANY SUCCESSOR
PROVISION), ONLY (a) TO CORPORATE OFFICE PROPERTIES, L.P.  (THE “ISSUER”), (b) UNDER A REGISTRATION
STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT (AND WHICH
CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH TRANSFER), (c) FOR SO LONG
AS THE SECURITIES ARE ELIGIBLE FOR RESALE UNDER RULE 144A, IN COMPLIANCE WITH
RULE 144A TO A PERSON IT REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A OR (d) UNDER ANOTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE 


 


1

















 


SECURITIES ACT (INCLUDING
RULE 144), SUBJECT TO THE ISSUER’S AND THE TRUSTEE’S RIGHT PRIOR TO ANY SUCH
OFFER, SALE OR TRANSFER UNDER CLAUSE (d) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM; AND (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS
SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND.


 


THIS LEGEND WILL BE REMOVED
ON THE EARLIER OF THE TRANSFER OF THIS SECURITY UNDER CLAUSE 2(b) ABOVE OR
ON ANY TRANSFER OF THIS SECURITY UNDER RULE 144 UNDER THE SECURITIES ACT (OR
ANY SUCCESSOR PROVISION).


 


2

















 


CORPORATE
OFFICE PROPERTIES, L.P.

4.25% EXCHANGEABLE SENIOR NOTES DUE 2030


 




	
  Dated:
  April 7, 2010

  	
   

  	
  PRINCIPAL AMOUNT

  
	
  No.:
  1

  	
   

  	
  $240,000,000

  
	
  CUSIP
  No.:  22003B AC0

  	
   

  	
   

  
	
  ISIN
  No.: US22003BAC00

  	
   

  	
   

  






 


CORPORATE OFFICE PROPERTIES,
L.P., a Delaware limited partnership (hereinafter called the “Issuer,” which term shall include any successor under the
Indenture hereinafter referred to), for value received, hereby promises to pay
to CEDE & CO., or registered assigns, upon presentation, the principal
sum of $240,000,000 (which principal amount may from time to time be decreased
to such other principal amounts by adjustments made on the records of the
Trustee hereinafter referred to in accordance with the Indenture referred to
below) on April 15, 2030 and to pay interest on the outstanding principal
amount thereon from October 15, 2010 or from the most recent Interest
Payment Date to which interest has been paid or duly provided for,
semi-annually in arrears on April 15 and October 15 in each year,
commencing on October 15, 2010, at the rate of 4.25% per annum, until the
entire principal hereof is paid or made available for payment.  The Notes will be fully and unconditionally
guaranteed by Corporate Office Properties Trust (the “Guarantor”),
on a senior unsecured basis, in accordance with the provisions of Article 15
of the Indenture.


 


The interest so payable, and
punctually paid or duly provided for on any Interest Payment Date will, as
provided in the Indenture, be paid to the Person in whose name this Note is
registered at the Close of Business on the Record Date for such interest which
shall be the April 1 or October 1, as the case may be, next preceding
such Interest Payment Date.  Payment of
the principal of and interest on this Note will be made at the office of the
Issuer maintained by the Issuer for such purposes, which shall initially be an
office or agency of the Trustee, or elsewhere as provided in the Indenture, in
such coin or currency of the United States of America as at the time of payment
is legal tender for payment of public and private debts; provided, however, that at the option of the Issuer, payment of
interest may be made by (i) check mailed to the address of the Person
entitled thereto as such address shall appear in the Security Register or (ii) transfer
to an account of the Person entitled thereto located inside the United States.


 


Each Note of this series is
one of a duly authorized issue of securities of the Issuer (herein called the “Notes”), issued under an Indenture, dated as of April 7,
2010 (the “Indenture”), between the Issuer,
the Guarantor and Wells Fargo Bank, National Association, as trustee (herein
called the “Trustee”).  Reference is hereby made to the Indenture for
a statement of the respective rights, limitations of rights, duties and
immunities thereunder of the Issuer, the Trustee and the Noteholders and of the
terms upon which the Notes are, and are to be, authenticated and delivered.


 


In case an Event of Default,
as defined in the Indenture, shall have occurred and be continuing, the
principal of and interest on all Notes may be declared, and upon said
declaration shall become, due and payable, in the manner, with the effect and
subject to the conditions provided in the Indenture.


 


As provided in and subject
to the provisions of the Indenture, unless the principal of all of the Notes of
this series at the time Outstanding shall already have become due and payable,
the Noteholder of this Note shall not have the right to institute any
proceeding with respect to the Indenture or for the appointment of a receiver
or trustee or for any other remedy thereunder, unless such Noteholder shall
have previously given the Trustee written notice of a continuing Event of
Default with respect to the Notes of this series, the Noteholders of not less
than 25% in principal amount of the Notes of this series at the time
Outstanding shall have made written request to the Trustee to institute
proceedings in respect of such Event of Default as Trustee and offered the
Trustee such reasonably security or indemnity as the 


 


3

















 


Trustee may require and the Trustee shall not
have received from the Noteholders of a majority in principal amount of Notes
of this series at the time Outstanding a direction inconsistent with such
request, and the Trustee shall have failed to institute any such proceeding for
60 days after receipt of such notice, request and offer of security or
indemnity.  The foregoing shall not apply
to any suit instituted by the Noteholder of this Note for the enforcement of
any payment of principal hereof or any interest on or after the respective due
dates expressed herein.


 


Prior to April 20,
2015, the Issuer may not redeem the Notes except to preserve the Guarantor’s
status as a real estate investment trust as described in Section 3.01 of
the Indenture.  Subject to the terms and
conditions of the Indenture, on or after April 20, 2015, the Issuer shall
have the right to redeem the Notes, in whole or from time to time in whole or
part, at a price equal to 100% of the principal amount of the Notes being
redeemed, plus accrued and unpaid interest. 
Any such redemption shall be upon at least 30 days’ and no more than 60
days’ notice to Noteholders.


 


Subject to the terms and
conditions of the Indenture, the Issuer will make all payments and deliveries
in respect of the Fundamental Change Repurchase Price, the Put Right Repurchase
Price, the redemption price and the principal amount on the Maturity Date, as
the case may be, to the Noteholder who surrenders a Note to a Paying Agent to
collect such payments in respect of the Note. 
The Issuer will pay cash amounts in money of the United States that at
the time of payment is legal tender for payment of public and private debts.


 


The Indenture contains
provisions permitting the Issuer and the Trustee in certain circumstances,
without the consent of the Noteholders, and in other circumstances, with the
consent of the Noteholders of not less than a majority in aggregate principal
amount of the Notes at the time Outstanding, evidenced as in the Indenture
provided, to execute supplemental indentures adding any provisions to or
changing in any manner or eliminating any of the provisions of the Indenture or
of any supplemental indenture or modifying in any manner the rights of the
Noteholders.  It is also provided in the
Indenture that the Noteholders of a majority in aggregate principal amount of the
Notes at the time Outstanding may on behalf of the Noteholders of all of the
Notes waive any past Default or Event of Default under the Indenture and its
consequences except as provided in the Indenture.  Any such consent or waiver by the Noteholder
of this Note (unless revoked as provided in the Indenture) shall be conclusive
and binding upon such Noteholder and upon all future Noteholders and owners of
this Note and any Notes which may be issued in exchange or substitution hereof,
irrespective of whether or not any notation thereof is made upon this Note or
such other Notes.


 


No reference herein to the
Indenture and no provision of this Note or of the Indenture shall alter or
impair the obligation of the Issuer, which is absolute and unconditional, to pay
the principal of and accrued and unpaid interest on this Note at the place, at
the respective times, at the rate and in the lawful money herein prescribed.


 


The Notes are issuable in
registered form without coupons in denominations of $1,000 principal amount and
integral multiples thereof.  At the
office or agency of the Issuer referred to on the face hereof, and in the
manner and subject to the limitations provided in the Indenture, without
payment of any service charge but with payment of a sum sufficient to cover any
tax or other governmental charge that may be imposed in connection with any
registration or exchange of Notes, Notes may be exchanged for a like aggregate
principal amount of Notes of other authorized denominations.


 


The Notes are not subject to
redemption through the operation of any sinking fund.


 


Upon the occurrence of a
Fundamental Change, the Noteholder has the right, at such Noteholder’s  option, to require the Issuer to repurchase
all of such Noteholder’s  Notes or any
portion 


 


4

















 


thereof (in principal amounts of $1,000 or
integral multiples thereof) on the Fundamental Change Repurchase Date at a
price equal to 100% of the principal amount of the Notes such Noteholder elects
to require the Issuer to repurchase, together with accrued and unpaid interest
to but excluding the Fundamental Change Repurchase Date.  The Issuer or, at the written request of the
Issuer, the Trustee shall provide to all Noteholders of record a notice of the
occurrence of a Fundamental Change and of the repurchase right arising as a
result thereof on or before the twentieth day after the occurrence of any
Fundamental Change.


 


On April 15, 2015, April 15,
2020 or April 15, 2025, the Noteholder has the right, at such Noteholder’s  option, to require the Issuer to repurchase
all of such Noteholder’s  Notes or any
portion thereof (in principal amounts of $1,000 or integral multiples thereof)
at a price equal to 100% of the principal amount of the Notes such Noteholder
elects to require the Issuer to repurchase, together with accrued and unpaid
interest to but excluding the Put Right Repurchase Date.  Noteholders shall submit their Notes for
repurchase to the Paying Agent at any time from the Open of Business on the
date that is 25 Business Days prior to the applicable Put Right Repurchase Date
until the Close of Business on the fifth Business Day prior to the Put Right
Repurchase Date.


 


Subject to the provisions of
the Indenture, the Noteholder has the right, at its option, to exchange all or
any portion (if the portion to be exchanged is $1,000 principal amount or an
integral multiple thereof) of such Notes at any time prior to the Close of
Business on the Scheduled Trading Day immediately preceding April 20,
2015, into cash, Common Shares or a combination thereof, in each case at the
Exchange Rate specified in the Indenture, as adjusted from time to time as
provided in the Indenture.  The initial
Exchange Rate is 20.7658 Common Shares for each $1,000 principal amount of Notes.  No fractional Common Shares will be issued
upon any exchange, but an adjustment in cash will be paid to the Holder, as
provided in the Indenture, in respect of any fraction of a share which would
otherwise be issuable upon the surrender of any Note or Notes for
exchange.  No adjustment shall be made
for dividends or any shares issued upon exchange of such Note except as
provided in the Indenture.


 


Upon due presentment for
registration of transfer of this Note at the office or agency of the Company, a
new Note or Notes of authorized denominations for an equal aggregate principal
amount will be issued to the transferee in exchange thereof, subject to the
limitations provided in the Indenture, without charge except for any tax,
assessments or other governmental charge imposed in connection therewith.


 


The Issuer, the Trustee, any
Authenticating Agent, any Paying Agent, any Exchange Agent and any Security
Registrar may deem and treat the registered Noteholder hereof as the absolute
owner of this Note (whether or not this Note shall be overdue and
notwithstanding any notation of ownership or other writing hereon), for the
purpose of receiving payment hereof, or on account hereof, for the exchange
hereof and for all other purposes, and neither the Issuer nor the Trustee nor
any other Authenticating Agent nor any Paying Agent nor any other Exchange
Agent nor any Security Registrar shall be affected by any notice to the
contrary.  All payments made to or upon
the order of such registered Noteholder shall, to the extent of the sum or sums
paid, satisfy and discharge liability for monies payable on this Note.


 


No recourse for the payment
of the principal of, or accrued and unpaid interest on, this Note, or for any
claim based hereon or otherwise in respect hereof, and no recourse under or
upon any obligation, covenant or agreement of the Issuer in the Indenture or
any indenture supplemental thereto or in any Note, or because of the creation
of any indebtedness represented thereby, shall be had against any incorporator,
shareholder, employee, agent, officer, director, trustee or subsidiary, as
such, past, present or future, of the Issuer or of any successor corporation,
either directly or through the Issuer or any successor corporation, whether by
virtue of any constitution, statute or rule of law or by the enforcement
of any assessment or 


 


5

















 


penalty or otherwise, all such liability
being, by the acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.


 


Terms used in this Note and
defined in the Indenture are used herein as therein defined.  Customary abbreviations may be used in the
name of a Noteholder or an assignee, such as TEN COM (=tenants in common),
TENANT (=tenants by the entireties), JT TEN (=joint tenants with right of
survivorship and not as tenants in common), CUST (=custodian), and U/G/M/A
(=Uniform gift to Minors Act).


 


THE INDENTURE AND THE NOTES,
INCLUDING THIS NOTE (WHICH SHALL BE DEEMED A CONTRACT MADE UNDER THE LAWS OF
THE STATE OF NEW YORK), SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH,
THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICT OF LAW PRINCIPLES
THEREOF.


 


Pursuant to a recommendation
promulgated by the Committee on Uniform Security Identification Procedures, the
Company has caused “CUSIP” numbers to be printed on the Notes of this series as
a convenience to the Noteholders of such Notes. 
No representation is made as to the correctness or accuracy of such
CUSIP numbers as printed on the Notes, and reliance may be placed only on the
other identification numbers printed hereon.


 


No Noteholder shall be
entitled to exchange such Notes for Common Shares to the extent that receipt of
such Common Shares would cause such Noteholder (together with such Noteholder’s  affiliates) to exceed the applicable
ownership limit contained in the Declaration of Trust of the Guarantor as then
in effect.


 


[This
space intentionally left blank.]


 


6

















 


Unless the certificate of
authentication hereon has been executed by or on behalf of the Trustee by
manual signature, this Note shall not be entitled to any benefit under the
Indenture or be valid or obligatory for any purpose.


 


7

















 


IN WITNESS WHEREOF, the
Issuer has caused this instrument to be duly executed by the undersigned
officer.


 


	
   

  	
  CORPORATE
  OFFICE PROPERTIES, L.P.

  
	
   

  	
   

  
	
   

  	
  By:

  	
  Corporate
  Office Properties Trust

  
	
   

  	
   

  	
  Its
  General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Randall M. Griffin

  
	
   

  	
   

  	
  Name:  Randall
  M. Griffin

  
	
   

  	
   

  	
  Title:    President &
  Chief Executive Officer

  



 


 


TRUSTEE’S
CERTIFICATE OF AUTHENTICATION:


 


This is one of the Notes of
the series designated therein referred to in the within-mentioned Indenture.


 


WELLS
FARGO BANK, NATIONAL ASSOCIATION, as Trustee


 


 


	
  By:

  	
  /s/
  Lynn M. Steiner

  	
   

  
	
   

  	
  Authorized
  Signatory

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  Dated:
  April 7, 2010

  	
   

  



 


8






 












 


NOTATION
OF GUARANTEE


 


The Guarantor listed below
(hereinafter referred to as the “Guarantor,”
which term includes any successors or assigns under the Indenture, dated the
date hereof, among the Guarantor, the Issuer (defined below) and Wells Fargo
Bank, National Association, as trustee (the “Indenture”)),
has irrevocably and unconditionally guaranteed on a senior basis the Guarantee
Obligations (as defined in Section 15.01 of the Indenture), which include (i) the
due and punctual payment of the principal of, premium, if any, and interest and
Additional Interest, if any, on the 4.25% Exchangeable Senior Notes due 2030
(the “Notes”) of Corporate Office Properties,
L.P., a Delaware limited partnership (the “Issuer”),
whether at maturity, by acceleration, call for redemption, upon a repurchase or
otherwise, the due and punctual payment of interest on the overdue principal
and premium, if any, and (to the extent permitted by law) interest on any
interest on the Notes, and the due and punctual performance of all other
obligations of the Issuer, to the Noteholders or the Trustee all in accordance
with the terms set forth in Article 15 of the Indenture, and (ii) in
case of any extension of time of payment or renewal of any Notes or any such
other obligations, that the same shall be promptly paid in full when due or
performed in accordance with the terms of the extension or renewal, whether at
maturity, by acceleration, call for redemption, upon a repurchase or otherwise.


 


The obligations of the
Guarantor to the Noteholders and to the Trustee pursuant to this Guarantee and
the Indenture are expressly set forth in Article 15 of the Indenture and
reference is hereby made to such Indenture for the precise terms of this
Guarantee.


 


No past, present or future
trustee, officer, employee, incorporator or shareholder (direct or indirect) of
the Guarantor (or any such successor entity), as such, shall have any liability
for any obligations of the Guarantor under this Guarantee or the Indenture or
for any claim based on, in respect of, or by reason of, such obligations or
their creation.


 


The Guarantor hereby waives
diligence, presentment, demand of payment, filing of claims with a court in the
event of merger or bankruptcy of the Issuer, any right to require a proceeding
first against the Issuer, the benefit of discussion, protest or notice with
respect to the Notes and all demands whatsoever.


 


This is a continuing
Guarantee and shall remain in full force and effect and shall be binding upon
the Guarantor and its successors and assigns until full and final payment of
all of the Issuer’s obligations under the Notes and Indenture or until legally
discharged in accordance with the Indenture and shall inure to the benefit of
the successors and assigns of the Trustee and the Noteholders, and, in the
event of any transfer or assignment of rights by any Noteholder or the Trustee,
the rights and privileges herein conferred upon that party shall automatically
extend to and be vested in such transferee or assignee, all subject to the
terms and conditions hereof.  This is a
Guarantee of payment and performance and not of collectability.


 


This Guarantee shall not be
valid or obligatory for any purpose until the certificate of authentication on
the Note upon which this Guarantee is noted shall have been executed by the
Trustee under the Indenture by the manual or facsimile signature of one of its
authorized officers.


 


The obligations of the
Guarantor under this Guarantee shall be limited to the extent necessary to
insure that it does not constitute a fraudulent conveyance under applicable
law.


 


THE TERMS OF ARTICLE 15 OF
THE INDENTURE ARE INCORPORATED HEREIN BY REFERENCE.  Capitalized terms used herein have the same
meanings given in the Indenture unless otherwise indicated.


 


9

















 


IN WITNESS WHEREOF, the
Guarantor has caused this instrument to be duly executed.


 


Dated:  April 7, 2010


 


 


	
   

  	
  CORPORATE
  OFFICE PROPERTIES TRUST

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Randall M. Griffin

  
	
   

  	
   

  	
      Name:

  	
  Randall
  M. Griffin

  
	
   

  	
   

  	
      Title:

  	
  President &
  Chief Executive Officer

  



 


10

















 


EXCHANGE
NOTICE


 


	
  TO:

  	
  CORPORATE OFFICE
  PROPERTIES, L.P.

  
	
   

  	
  WELLS FARGO BANK,
  NATIONAL ASSOCIATION, as Trustee

  



 


The undersigned registered
owner of this Note hereby irrevocably exercises the option to exchange this
Note, or the portion thereof (which is $1,000 or a multiple thereof) below
designated, into cash and, if applicable, Common Shares, cash, or a combination
thereof, as the case may be, at the election of the Issuer, in accordance with
the terms of the Indenture referred to in this Note, and directs that the
Common Shares, if any, issuable and deliverable upon such exchange, together
with any check in payment for cash, if any, payable upon exchange or for fractional
shares and any


 


Notes representing any
unexchanged principal amount hereof, be issued and delivered to the registered
holder hereof unless a different name has been indicated below.  Capitalized terms used herein but not defined
shall have the meanings ascribed to such terms in the Indenture.  If shares or any portion of this Note not
exchanged are to be issued in the name of a person other than the undersigned,
the undersigned will provide the appropriate information below and pay all
transfer taxes payable with respect thereto. 
Any amount required to be paid by the undersigned on account of interest
accompanies this Note.


 


The undersigned registered
owner of this Note hereby certifies that it or the Person on whose behalf the
Notes are being exchanged is a qualified institutional buyer within the meaning
of Rule 144A under the Securities Act of 1933, as amended.


 


	
  Dated:

  	
   

  	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature(s)

  
	
   

  	
   

  
	
   

  	
  Signature(s) must be guaranteed by an “eligible
  guarantor institution” meeting the requirements of the Note
  Registrar, which requirements include membership or participation in the
  Security Transfer Agent Medallion Program (“STAMP”)
  or such other “signature guarantee program” as
  may be determined by the Note Registrar in addition to, or in substitution
  for, STAMP, all in accordance with the Securities Exchange Act of 1934, as
  amended.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature Guarantee

  



 


11

















 


Fill in the registration of
Common Shares, if any, if to be issued, and Notes if to be delivered, and the
person to whom cash and payment for fractional shares is to be made, if to be
made, other than to and in the name of the registered holder:


 


	
  Please
  print name and address

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  (Name)

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  (Street
  Address)

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  (City,
  State and Zip Code)

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  Principal
  amount to be exchanged (if less than all):

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
  Social Security or Other Taxpayer Identification Number:

  	
   

  
	
   

  	
   

  
	
   

  	
   

  



 


NOTICE:  The signature on this Exchange Notice must
correspond with the name as written upon the face of the Note in every
particular without alteration or enlargement or any change whatever.


 


12

















 


REPURCHASE
NOTICE


 


TO:                            CORPORATE
OFFICE PROPERTIES, L.P.

WELLS FARGO BANK, NATIONAL ASSOCIATION


 


The undersigned registered
owner of this Note hereby irrevocably acknowledges receipt of a notice from
Corporate Office Properties, L.P.  (the “Issuer”) regarding the right of Noteholders to elect to
require the Issuer to repurchase the Notes and requests and instructs the Issuer
to repay the entire principal amount of this Note, or the portion thereof
(which is $1,000 or an integral multiple thereof) below designated, in cash, in
accordance with the terms of the Indenture at the price of 100% of such entire
principal amount or portion thereof, together with accrued and unpaid interest
to, but excluding, the Repurchase Date or the Fundamental Change Repurchase
Date, as the case may be, to the registered holder hereof.  Capitalized terms used herein but not defined
shall have the meanings ascribed to such terms in the Indenture.  The Notes shall be repurchased by the Issuer
as of the Put Right Repurchase Date or the Fundamental Change Repurchase Date,
as the case may be, pursuant to the terms and conditions specified in the Indenture.


 


NOTICE:  The above signatures of the holder(s) hereof
must correspond with the name as written upon the face of the Note in every
particular without alteration or enlargement or any change whatever.  Note Certificate Number (if applicable):


 


 


	
   

  	
   

  	
   

  



 


Principal amount to be
repurchased (if less than all, must be $1,000 or whole multiples thereof):


 


	
   

  	
   

  	
   

  



 


	
  Social
  Security or Other Taxpayer Identification Number:

  	
   

  



 


 


	
  Dated:

  	
   

  	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature(s)

  
	
   

  	
   

  
	
   

  	
  Signature(s) must be guaranteed by an “eligible guarantor
  institution” meeting the requirements of the Note Registrar, which
  requirements include membership or participation in the Security Transfer
  Agent Medallion Program (“STAMP”) or
  such other “signature guarantee program” as
  may be determined by the Note Registrar in addition to, or in substitution
  for, STAMP, all in accordance with the Securities Exchange Act of 1934, as
  amended.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature Guarantee

  



 


13

















 


ASSIGNMENT


 


For value received
                                          
hereby sell(s) assign(s) and transfer(s) unto
                                                            
(Please insert social security or other Taxpayer Identification Number of
assignee) the within Note, and hereby irrevocably constitutes and appoints
                                                  
attorney to transfer said Note on the books of the Issuer, with full power of
substitution in the premises.


 


In connection with any
transfer of the Note, the undersigned confirms that such Note is being
transferred:


 


o                                    To Corporate
Office Properties, L.P., Corporate Office Properties Trust or a subsidiary of
Corporate Office Properties, L.P.; or


 


o                                    Pursuant to and
in compliance with Rule 144 under the Securities Act of 1933, as amended;
or


 


o                                    To a person the
undersigned reasonably believes is a qualified institutional buyer that is
purchasing for its own account or for the account of another qualified
institutional buyer and to whom notice is given that the transfer is being made
in reliance on Rule 144A, all in compliance with Rule 144A (if
available); or


 


o                                    Pursuant to a
Registration Statement which has been declared effective under the Securities
Act of 1933, as amended, and which continues to be effective at the time of
transfer.


 


Unless one of the boxes is
checked, the Trustee will refuse to register any of the Notes evidenced by this
certificate in the name of any person other than the registered holder thereof.


 


	
  Dated:

  	
   

  	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature(s)

  
	
   

  	
   

  
	
   

  	
  Signature(s) must be guaranteed by an “eligible
  guarantor institution” meeting the requirements of the Note
  Registrar, which requirements include membership or participation in the
  Security Transfer Agent Medallion Program (“STAMP”)
  or such other “signature guarantee program” as
  may be determined by the Note Registrar in addition to, or in substitution
  for, STAMP, all in accordance with the Securities Exchange Act of 1934, as
  amended.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Signature Guarantee

  



 


14

















 


NOTICE:  The signature on this Assignment must
correspond with the name as written upon the face of the Note in every
particular without alteration or enlargement or any change whatever.


 


15

















 


SCHEDULE
OF INCREASES OR DECREASES IN NOTE


 


The initial principal amount
of this Global Note is
                                
($                            ).  The following increases or decreases in part
of this Note have been made:


 


	
  Date

  	
   

  	
  Amount of

  Increase in

  Principal

  Amount of this

  Note

  	
   

  	
  Amount of

  Decrease in

  Principal

  Amount of this

  Note

  	
   

  	
  Principal Amount of

  this Note following 

  such Increase or

  Decrease

  	
   

  	
  Signature of

  Authorized Signatory

  of Trustee

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  



 


16