EXHIBIT 4.1






SUPPLEMENTAL
INDENTURE NO. 18


by
and between


HRPT
PROPERTIES TRUST


and


U.S.
BANK NATIONAL ASSOCIATION


as of
September 18, 2007


 


SUPPLEMENTAL
TO THE INDENTURE DATED AS OF JULY 9, 1997


 






HRPT
PROPERTIES TRUST


6.65%
Senior Notes due 2018






 


 


 






 


 
















 


This SUPPLEMENTAL
INDENTURE NO. 18 (this “Supplemental Indenture”) made and entered into as of
September 18, 2007 between HRPT PROPERTIES TRUST, a Maryland real estate
investment trust (the “Company”), and U.S.
BANK NATIONAL ASSOCIATION, a national banking association, as trustee (the “Trustee”),


WITNESSETH
THAT:


WHEREAS, the Company and
the Trustee are parties to an Indenture, dated as of July 9, 1997 (the “Indenture”),
relating to the Company’s issuance, from time to time, of various series of
debt securities;


WHEREAS, the Company has
determined to issue debt securities known as its 6.65% Senior Notes due 2018;
and


WHEREAS, the Indenture
provides that certain terms and conditions for each series of debt securities
issued by the Company thereunder may be set forth in an indenture supplemental
to the Indenture;


NOW, THEREFORE, THIS
SUPPLEMENTAL INDENTURE WITNESSETH:


ARTICLE 1


DEFINED TERMS


Section
1.1             The following
definitions supplement, and, to the extent inconsistent with, replace the
definitions in Section 101 of the Indenture:


“Acquired Debt” means
Debt of a Person or entity (i) existing at the time such Person or entity
becomes a Subsidiary or (ii) assumed in connection with the acquisition of
assets from such Person or entity, in each case, other than Debt incurred in
connection with, or in contemplation of, such Person or entity becoming a
Subsidiary or such acquisition.  Acquired
Debt shall be deemed to be incurred on the date of the related acquisition of
assets from any Person or entity or the date the acquired Person or entity
becomes a Subsidiary.


“Annual Debt Service” as
of any date means the maximum amount which is expensed in any 12-month period
for interest on Debt of the Company and its Subsidiaries.


“Business Day” means any
day other than a Saturday or Sunday or a day on which banking institutions in
the City of New York or in the city in which the Corporate Trust Office of the
Trustee is located, are required or authorized to close.


“Capital Stock” means,
with respect to any Person, any capital stock (including preferred stock),
shares, interests, participation or other ownership interests (however
designated) of such Person and any rights (other than debt securities
convertible into or exchangeable for capital stock), warrants or options to purchase
any thereof.


“Consolidated Income
Available for Debt Service” for any period means Earnings from Operations of
the Company and its Subsidiaries plus amounts which have been deducted, and


 

















minus amounts
which have been added, for the following (without duplication): (i) interest on
Debt of the Company and its Subsidiaries, (ii) provision for taxes of the
Company and its Subsidiaries based on income, (iii) amortization of debt
discount and deferred financing costs, (iv) provisions for gains and losses on
properties and property depreciation and amortization, (v) the effect of any
noncash charge resulting from a change in accounting principles in determining
Earnings from Operations for such period and (vi) amortization of deferred
charges.


“Corporate Trust Office”
means the corporate trust office of the Trustee which it designates as the
office at which the agreement in question will be administered (which it may
change by notice from time to time), presently located at One Federal Street,
3rd Floor, Boston, Massachusetts 02110.


“Debt” of the Company or
any Subsidiary means, without duplication, any indebtedness of the Company or
any Subsidiary, whether or not contingent, in respect of (i) borrowed money or
evidenced by bonds, notes, debentures or similar instruments, (ii) indebtedness
for borrowed money secured by any Encumbrance existing on property owned by the
Company or any Subsidiary, to the extent of the lesser of (x) the amount of
indebtedness so secured and (y) the fair market value of the property subject
to such Encumbrance, (iii) the reimbursement obligations, contingent or
otherwise, in connection with any letters of credit actually issued (other than
letters of credit issued to provide credit enhancement or support with respect
to other indebtedness of the Company or any Subsidiary otherwise reflected as
Debt hereunder) or amounts representing the balance deferred and unpaid of the
purchase price of any property or services, except any such balance that
constitutes an accrued expense or trade payable, or all conditional sale
obligations or obligations under any title retention agreement, (iv) the
principal amount of all obligations of the Company or any Subsidiary with
respect to redemption, repayment or other repurchase of any Disqualified Stock,
or (v) any lease of property by the Company or any Subsidiary as lessee which
is reflected on the Company’s consolidated balance sheet as a capitalized lease
in accordance with GAAP, to the extent, in the case of items of indebtedness
under (i) through (iii) above, that any such items (other than letters of
credit) would appear as a liability on the Company’s consolidated balance sheet
in accordance with GAAP, and also includes, to the extent not otherwise
included, any obligation by the Company or any Subsidiary to be liable for, or
to pay, as obligor, guarantor or otherwise (other than for purposes of
collection in the ordinary course of business), Debt of another Person (other
than the Company or any Subsidiary) (it being understood that Debt shall be
deemed to be incurred by the Company or any Subsidiary whenever the Company or
such Subsidiary shall create, assume, guarantee or otherwise become liable in
respect thereof).


“Disqualified Stock”
means, with respect to any Person, any Capital Stock of such Person which by
the terms of such Capital Stock (or by the terms of any security into which it
is convertible or for which it is exchangeable or exercisable), upon the
happening of any event or otherwise (i) matures or is mandatorily redeemable,
pursuant to a sinking fund obligation or otherwise (other than Capital Stock
which is redeemable solely in exchange for common stock or shares), (ii) is
convertible into or exchangeable or exercisable for Debt or Disqualified Stock,
or (iii) is redeemable at the option of the Holder thereof, in whole or in part
(other than Capital Stock which is redeemable solely in exchange for common
stock or shares), in each case on or prior to the stated maturity of the Notes.


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“Earnings from Operations”
for any period means net earnings excluding gains and losses on sales of
investments, extraordinary items, gains and losses on early extinguishment of
debt and property valuation losses, as reflected in the financial statements of
the Company and its Subsidiaries for such period, determined on a consolidated
basis in accordance with GAAP.


“Encumbrance” means any
mortgage, lien, charge, pledge or security interest of any kind.


“Make-Whole Amount” means, in connection with any optional redemption
or accelerated payment of any Notes prior to July 15, 2017, the excess, if any,
of (i) the aggregate present value as of the date of such redemption or
accelerated payment of each dollar of principal being redeemed or paid and the
amount of interest (exclusive of interest accrued to the date of redemption or
accelerated payment) that would have been payable in respect of such dollar if
such redemption or accelerated payment had been made on July 15, 2017,
determined by discounting, on a semiannual basis, such principal and interest
at the Reinvestment Rate (determined on the third Business Day preceding the
date such notice of redemption is given or declaration of acceleration is made)
from the respective dates on which such principal and interest would have been
payable if such redemption or accelerated payment had been made on July 15,
2017, over (ii) the aggregate principal amount of the Notes being redeemed or
paid.  In the case of any redemption or
accelerated payment of notes on or after July 15, 2017, the Make-Whole Amount
means zero.  For purposes of this
Supplemental Indenture and the Notes, references in the Indenture to the
payment of the principal (and premium, if any) and interest on the Notes shall
be deemed to include the payment of the Make-Whole Amount, if any, due upon
redemption with respect to the Notes. 
The Make-Whole Amount shall be calculated by the Company and set forth
in an Officer’s Certificate delivered to the Trustee, and the Trustee shall be
entitled to rely on said Officer’s Certificate.


“Notes” means the Company’s
6.65% Senior Notes due 2018, issued
under this Supplemental Indenture and the Indenture, as amended or supplemented
from time to time.


“Reinvestment Rate” means
a rate per annum equal to the sum of 0.40% (forty one-hundredths of one
percent) plus the yield on treasury securities at constant maturity under the
heading “Week Ending” published in the Statistical Release under the caption “Treasury
Constant Maturities” for the maturity (rounded to the nearest month)
corresponding to the remaining life to maturity (which, in the case of
maturities corresponding to the principal and interest due on the notes at
their maturity, shall be deemed to be July
15, 2017), as of the payment date of the principal being redeemed or
paid.  If no maturity exactly corresponds
to such maturity, yields for the two published maturities most closely
corresponding to such maturity shall be calculated pursuant to the immediately
preceding sentence and the Reinvestment Rate shall be interpolated or
extrapolated from such yields on a straight-line basis, rounding in each of
such relevant periods to the nearest month. 
For purposes of calculating the Reinvestment Rate, the most recent
Statistical Release published prior to the date of determination of the
Make-Whole Amount shall be used.


“Secured Debt” means Debt
secured by any mortgage, lien, charge, pledge or security interest of any kind.


“Statistical Release”
means the statistical release designated “H.15(519)” or any successor publication
which is published weekly by the Federal Reserve System and which


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establishes yields
on actively traded United States government securities adjusted to constant
maturities or, if such statistical release is not published at the time of any
determination under this Supplemental Indenture, then any publicly available
source of similar market data which shall be designated by the Company.


“Subsidiary” means any
corporation or other entity of which a majority of (i) the voting power of the
voting equity securities or (ii) the outstanding equity interests are owned,
directly or indirectly, by the Company or one or more other Subsidiaries of the
Company.  For the purposes of this
definition, “voting equity securities” means equity securities having voting
power for the election of directors, whether at all times or only so long as no
senior class of security has such voting power by reason of any contingency.


“Total Assets” as of any
date means the sum of (i) the Undepreciated Real Estate Assets and (ii) all
other assets of the Company and its Subsidiaries determined in accordance with
GAAP (but excluding accounts receivable and intangibles).


“Total Unencumbered
Assets” means the sum of (i) those Undepreciated Real Estate Assets not subject
to an Encumbrance for borrowed money and (ii) all other assets of the Company
and its Subsidiaries not subject to an Encumbrance for borrowed money
determined in accordance with GAAP (but excluding accounts receivable and
intangibles).


“Undepreciated Real
Estate Assets” as of any date means the cost (original cost plus capital
improvements) of real estate assets of the Company and its Subsidiaries on such
date, before depreciation and amortization, determined on a consolidated basis
in accordance with GAAP.


“Unsecured Debt” means
Debt which is not secured by any of the properties of the Company or any
Subsidiary.


ARTICLE
2


TERMS
OF THE NOTES


Section 2.1             Pursuant
to Section 301 of the Indenture, the Notes shall have the following terms and
conditions:


(a)           Title; Aggregate
Principal Amount; Form of Notes.  The
Notes shall be Registered Securities under the Indenture and shall be known as
the Company’s “6.65% Senior Notes due 2018.” 
The Notes will be limited to an aggregate principal amount of
$250,000,000, subject to the right of the Company to reopen such series for
issuances of additional securities of such series and except as provided in
this Section or in Section 306 of the Indenture.  The Notes (together with the Trustee’s
certificate of authentication) shall be substantially in the form of Exhibit A
hereto, which is hereby incorporated in and made a part of this Supplemental
Indenture.


The Notes will be issued
in the form of one or more registered global securities without coupons (“Global
Notes”) that will be deposited with, or on behalf of, The Depository Trust
Company (“DTC”), and registered in the name of DTC’s nominee, Cede &
Co.  Except under the circumstance
described below, the Notes will not be issuable in definitive form.  Unless and until it is exchanged in whole or
in part for the individual Notes represented thereby, a Global Note


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may not be
transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC
to DTC or another nominee of DTC or by DTC or any nominee of DTC to a successor
depositary or any nominee of such successor.


So long as DTC or its
nominee is the registered owner of a Global Note, DTC or such nominee, as the
case may be, will be considered the sole owner or holder of the Notes
represented by such Global Note for all purposes under this Supplemental
Indenture.  Except as described below,
owners of beneficial interest in Notes evidenced by a Global Note will not be
entitled to have any of the individual Notes represented by such Global Note
registered in their names, will not receive or be entitled to receive physical
delivery of any such Notes in definitive form and will not be considered the
owners or holders thereof under the Indenture or this Supplemental Indenture.


If DTC is at any time
unwilling, unable or ineligible to continue as depositary and a successor
depositary is not appointed by the Company within 90 days, the Company will
issue individual Notes in exchange for the Global Note or Global Notes
representing such Notes.  In addition,
the Company may at any time and in its sole discretion, subject to certain
limitations set forth in the Indenture, determine not to have any of such Notes
represented by one or more Global Notes and, in such event, will issue
individual Notes in exchange for the Global Note or Global Notes representing
the Notes.  Individual Notes so issued
will be issued in denominations of $1,000 and integral multiples thereof.


(b)           Interest and
Interest Rate.  The Notes will bear
interest at a rate of 6.65%  per annum, from September 18, 2007 (or, in the
case of Notes issued upon any reopening of this series of Notes, from the date
designated by the Company in connection with such reopening) or from the immediately
preceding Interest Payment Date to which interest has been paid or duly
provided for, payable semiannually in arrears on each January 15 and July 15,
commencing January 15, 2008  (each of
which shall be an “Interest Payment Date”), to the Persons in whose names the
Notes are registered in the Security Register at the close of business on the
day falling 14 calendar days (whether or not a Business Day) next preceding
such Interest Payment Date (each, a “Regular Record Date”).


(c)           Principal
Repayment; Currency.  The stated
maturity of the Notes is January 15, 2018; provided,
however, the Notes may be earlier redeemed at the option of the Company as
provided in paragraph (d) below.  The
principal of each Note payable on its maturity date shall be paid against
presentation and surrender thereof at the Corporate Trust Office of the Trustee
in such coin or currency of the United States of America as at the time of
payment is legal tender for the payment of public or private debts.  The Company will not pay Additional Amounts
(as defined in the Indenture) on the Notes.


(d)           Redemption at the Option of the
Company; Acceleration.  The Notes
will be subject to redemption at any time at the option of the Company, in
whole or in part, upon not less than 30 nor more than 60 days’ notice to each
Holder of Notes to be redeemed at its address appearing in the Security
Register, at a price equal to the sum of (i) the outstanding principal amount
of the Notes being redeemed, plus accrued and unpaid interest to but excluding
the applicable Redemption Date, plus (ii) the Make-Whole Amount, if any.  If the notes are redeemed on or after July 15, 2017, the redemption price will
not include the Make-Whole Amount.  Upon


 


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the acceleration of the
Notes in accordance with Section 502 of the Indenture, the Company shall pay
the amount specified in Section 4.2 of this Supplemental Indenture.


(e)           Notices.  All notices and other communications
hereunder shall be in writing and shall be deemed to have been duly given if
mailed or transmitted by any standard form of telecommunication.  Notices to the Company shall be directed to
it at 400 Centre Street, Newton, Massachusetts 02458, Attention: President;
notices to the Trustee shall be directed to it at One Federal Street, 3rd
Floor, Boston, Massachusetts 02110, Attention: Corporate Trust Department, Re:
HRPT Properties Trust 6.65% Senior Notes due 2018; or as to either party, at such other address as shall be
designated by such party in a written notice to the other party.


(f)            Global Note
Legend.  Each Global Note shall bear
the following legend on the face thereof:


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.


(g)           Applicability of
Discharge, Defeasance and Covenant Defeasance Provisions.  The Discharge, Defeasance and Covenant
Defeasance provisions in Article Fourteen of the Indenture will apply to the
Notes.


ARTICLE
3


ADDITIONAL
COVENANTS


Section 3.1             In
addition to the covenants of the Company set forth in Article Ten of the
Indenture, for the benefit of the Holders of the Notes:


(a)           Limitations on
Incurrence of Debt.


(i)            The Company will not, and will not
permit any Subsidiary to, incur any Debt if, immediately after giving effect to
the incurrence of such additional Debt and the application of the proceeds
thereof, the aggregate principal amount of all outstanding Debt of the Company
and its Subsidiaries on a consolidated basis determined in accordance with GAAP
is greater than 60% of the sum (“Adjusted Total Assets”) of (without
duplication) (A) the Total Assets of the Company and its Subsidiaries as of the
end of the calendar quarter covered in the Company’s Annual Report on Form
10-K, or the Quarterly


 


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Report on Form 10-Q, as the
case may be, most recently filed with the Securities and Exchange Commission
(or, if such filing is not permitted under the Securities Exchange Act of 1934,
as amended, with the Trustee) prior to the incurrence of such additional Debt
and (B) the purchase price of any real estate assets or mortgages receivable
acquired, and the amount of any securities offering proceeds received (to the
extent that such proceeds were not used to acquire real estate assets or
mortgages receivable or used to reduce Debt), by the Company or any Subsidiary
since the end of such calendar quarter, including those proceeds obtained in
connection with the incurrence of such additional Debt.


(ii)           In addition to the foregoing
limitations on the incurrence of Debt, the Company will not, and will not
permit any Subsidiary to, incur any Secured Debt if, immediately after giving
effect to the incurrence of such additional Secured Debt and the application of
the proceeds thereof, the aggregate principal amount of all outstanding Secured
Debt of the Company and its Subsidiaries on a consolidated basis is greater
than 40% of Adjusted Total Assets.


(iii)          In addition to the foregoing
limitations on the incurrence of Debt, the Company will not, and will not
permit any Subsidiary to, incur any Debt if the ratio of Consolidated Income
Available for Debt Service to the Annual Debt Service for the four consecutive
fiscal quarters most recently ended prior to the date on which such additional
Debt is to be incurred shall have been less than 1.5 to 1.0, on a pro forma
basis after giving effect thereto and to the application of the proceeds
therefrom, and calculated on the assumption that (A) such Debt and any
other Debt incurred by the Company and its Subsidiaries since the first day of
such four-quarter period and the application of the proceeds therefrom,
including to refinance other Debt, had occurred at the beginning of such
period; (B) the repayment or retirement of any other Debt by the Company
and its Subsidiaries since the first date of such four-quarter period had been
repaid or retired at the beginning of such period (except that, in making such
computation, the amount of Debt under any revolving credit facility shall be
computed based upon the average daily balance of such Debt during such period);
(C) in the case of Acquired Debt or Debt incurred in connection with any
acquisition since the first day of such four-quarter period, the related
acquisition had occurred as of the first day of such period with appropriate
adjustments with respect to such acquisition being included in such pro forma
calculation; and (D) in the case of any acquisition or disposition by the
Company or its Subsidiaries of any asset or group of assets since the first day
of such four-quarter period, whether by merger, stock purchase or sale, or
asset purchase or sale, such acquisition or disposition or any related
repayment of Debt had occurred as of the first day of such period with the
appropriate adjustments with respect to such acquisition or disposition being
included in such pro forma calculation. 
If the Debt giving rise to the need to make the foregoing calculation or
any other Debt incurred after the first day of the relevant four-quarter period
bears interest at a floating rate then, for purposes of calculating the Annual
Debt Service, the interest rate on such Debt shall be computed on a pro forma
basis as if the average interest rate which would have been in effect during
the entire such four-quarter period had been the applicable rate for the entire
such period.


(b)           Maintenance of
Total Unencumbered Assets.  The
Company and its Subsidiaries will at all times maintain Total Unencumbered
Assets of not less than 150% of the


 


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aggregate
outstanding principal amount of the Unsecured Debt of the Company and its
Subsidiaries on a consolidated basis.


ARTICLE 4


ADDITIONAL EVENTS OF DEFAULT


Section 4.1             For
purposes of this Supplemental Indenture and the Notes, in addition to the
Events of Default set forth in Section 501 of the Indenture, it shall also
constitute an “Event of Default” if a default under any bond, debenture, note
or other evidence of indebtedness of the Company (including a default with
respect to any other series of securities), or under any mortgage, indenture or
other instrument of the Company under which there may be issued or by which
there may be secured or evidenced any indebtedness for money borrowed by the
Company (or by any Subsidiary, the repayment of which the Company has
guaranteed or for which the Company is directly responsible or liable as
obligor or guarantor) having an aggregate principal amount exceeding
$20,000,000, whether such indebtedness now exists or shall hereafter be
incurred or created, which default shall have resulted in such indebtedness
becoming or being declared due and payable prior to the date on which it would
otherwise have become due and payable, without such indebtedness having been
discharged, or such acceleration having been rescinded or annulled, within a
period of ten days after there shall have been given, by registered or
certified mail, to the Company by the Trustee or to the Company and the Trustee
by the Holders of at least 25% in principal amount of the outstanding Notes, a
written notice specifying such default and requiring the Company to cause such
indebtedness to be discharged or cause such acceleration to be rescinded or
annulled and stating that such notice is a “Notice of Default” hereunder.


Section 4.2             Notwithstanding
any provisions to the contrary in the Indenture, upon any acceleration of the
Notes under Section 502 of the Indenture, the amount immediately due and
payable in respect of the Notes shall equal the outstanding principal amount
thereof, plus accrued and unpaid interest thereon, plus, if such acceleration
occurs prior to July 15, 2017, the
Make-Whole Amount.


ARTICLE
5


EFFECTIVENESS


This Supplemental
Indenture shall be effective for all purposes as of the date and time this
Supplemental Indenture has been executed and delivered by the Company and the
Trustee in accordance with Article Nine of the Indenture.  As supplemented hereby, the Indenture is
hereby confirmed as being in full force and effect.


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ARTICLE
6


MISCELLANEOUS


Section
6.1             In the event any
provision of this Supplemental Indenture shall be held invalid or unenforceable
by any court of competent jurisdiction, such holding shall not invalidate or
render unenforceable any other provision hereof or any provision of the
Indenture.


Section 6.2             To
the extent that any terms of this Supplemental Indenture or the Notes are
inconsistent with the terms of the Indenture, the terms of this Supplemental
Indenture or the Notes shall govern and supersede such inconsistent terms.


Section 6.3             This
Supplemental Indenture shall be governed by and construed in accordance with
the laws of The Commonwealth of Massachusetts.


Section 6.4             This
Supplemental Indenture may be executed in several counterparts, each of which
shall be an original and all of which shall constitute but one and the same
instrument.


[Remainder of page
intentionally left blank.]


 


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IN WITNESS WHEREOF, the
Company and the Trustee have caused this Supplemental Indenture to be executed
as an instrument under seal in their respective corporate names as of the date
first above written.


	
   

  	
  HRPT PROPERTIES TRUST

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ John C. Popeo

  
	
   

  	
   

  	
  Name: John C. Popeo

  
	
   

  	
   

  	
  Title: Treasurer and Chief Financial Officer

  
	
   

  	
   

  	
   

  
	
   

  	
  U.S. BANK NATIONAL ASSOCIATION,

  
	
   

  	
  as Trustee

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ James Freeman

  
	
   

  	
   

  	
  Name: James Freeman

  
	
   

  	
   

  	
  Title: Vice President

  



 


 


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EXHIBIT A


FORM
OF NOTE


[Face of Note]


6.65% Senior Note due 2018


No. R-                                                                                                                                                                                               $         


HRPT
PROPERTIES TRUST


promises
to pay to                             
or registered assigns, the principal sum of                               
($         ) on January 15, 2018, subject to the terms set forth on the
reverse of this Note and the terms of the Indenture referred to therein.


	
  Interest Payment Dates:

  	
   

  	
  each January 15 and July 15, commencing January 15,
  2008

  
	
   

  	
   

  	
   

  
	
  Interest Record Dates:

  	
   

  	
  the day falling 14 calendar days prior to any
  Interest Payment Date.

  



 


CUSIP No.:
                       


	
   

  	
  HRPT PROPERTIES TRUST

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
   

  	
  Name:

  
	
   

  	
   

  	
  Title:

  



 


	
  Attest:

  	
   

  	
   

  
	
  [SEAL]

  	
   

  
	
   

  	
   

  	
   

  
	
  CERTIFICATE OF AUTHENTICATION

  	
   

  
	
   

  	
   

  	
   

  
	
  Dated:

  	
   

  
	
   

  	
   

  	
   

  
	
  This is one of the Notes referred to in the within-mentioned
  Indenture:

  
	
   

  	
   

  	
   

  
	
  U.S. BANK NATIONAL ASSOCIATION, as Trustee

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  
	
   

  	
  Authorized Officer

  	
   

  
					



 


 


 

















[THE
FOLLOWING CONSTITUTES THE REVERSE OF THE SECURITY]


HRPT
PROPERTIES TRUST


6.65% Senior Note due 2018


Capitalized terms used
herein have the meanings assigned to them in the Indenture (as defined below)
unless otherwise indicated.


1.             Interest.  HRPT Properties Trust, a Maryland real estate
investment trust (the “Company”), promises to pay interest on the principal
amount of this Note at the rate and in the manner specified below.


The
Company shall pay in cash interest on the principal amount of this Note at the
rate per annum of 6.65%. The Company will pay interest semiannually in arrears
on each January 15 and July 15, commencing January 15, 2008, or, if any such
day is not a Business Day (as defined in the Indenture), on the next succeeding
Business Day (each an “Interest Payment Date”), to Holders of record on the day
falling 14 calendar days immediately preceding such Interest Payment Date (whether
or not a Business Day).


Interest
will be computed on the basis of a 360-day year consisting of twelve 30-day
months. Interest shall accrue from the most recent date to which interest has
been paid or, if no interest has been paid, from September 18, 2007.


2.             Method of
Payment.  The Company will pay
interest on this Note (except defaulted interest) on each Interest Payment Date
to the Person in whose name this Note is registered in the Security Register at
the close of business on the Interest Record Date next preceding such Interest
Payment Date.  The Company will pay
principal and interest in money of the United States that at the time of
payment is legal tender for payment of public and private debts.  The Company, however, may pay principal,
premium, if any, and interest by check payable in such money.  It may mail an interest check to a Holder’s
registered address.


3.             Indenture.  The Company issued the Notes under an
Indenture, dated as of July 9, 1997, and a Supplemental Indenture No. 18
thereto, dated as of September 18, 2007 (collectively, the “Indenture”),
between the Company and the Trustee.  The
terms of the Notes include those stated in the Indenture and those made part of
the Indenture by reference to the Trust Indenture Act of 1939 as in effect on
the date of the Indenture.  The Notes are
subject to all such terms, and Holders of the Notes are referred to the
Indenture and such Act for a statement of such terms.  The terms of the Indenture shall govern any
inconsistencies between the Indenture and the Notes.  The Notes are unsecured general obligations
of the Company limited to $250,000,000 in aggregate principal amount, except as
otherwise provided in the Indenture.


4.             Optional
Redemption.  The Notes will be
subject to redemption at any time at the option of the Company, in whole or in
part, upon not less than 30 nor more than 60 days’ notice, at a redemption
price equal to the sum of (i) the principal amount of the Notes being redeemed,
plus accrued and unpaid interest to but excluding the applicable Redemption
Date and (ii) the Make-Whole Amount, if any. 
If the Notes are redeemed on or after July 15, 2017, the redemption
price will not include the Make-Whole Amount.


 


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As
used herein the term “Make-Whole Amount” means, in connection with any optional
redemption or accelerated payment of any Notes prior to July 15, 2017, the
excess, if any, of (i) the aggregate present value as of the date of such
redemption or accelerated payment of each dollar of principal being redeemed or
paid and the amount of interest (exclusive of interest accrued to the date of
redemption or accelerated payment) that would have been payable in respect of
such dollar if such redemption or accelerated payment had been made on July 15,
2017, determined by discounting, on a semiannual basis, such principal and
interest at the Reinvestment Rate (determined on the third Business Day
preceding the date such notice of redemption is given or declaration of
acceleration is made) from the respective dates on which such principal and
interest would have been payable if such redemption or accelerated payment had
been made on July 15, 2017, over (ii) the aggregate principal amount of the
Notes being redeemed or paid.  In the
case of any redemption or accelerated payment of notes on or after July 15,
2017, the Make-Whole Amount means zero. 
For purposes of the Indenture and the Notes, references in the Indenture
to the payment of the principal (and premium, if any) and interest on the Notes
shall be deemed to include the payment of the Make-Whole Amount, if any, due
upon redemption with respect to the Notes. 
The Make-Whole Amount shall be calculated by the Company and set forth
in an Officer’s Certificate delivered to the Trustee, and the Trustee shall be
entitled to rely on said Officer’s Certificate.


As
used herein the term “Reinvestment Rate” means a rate per annum equal to the
sum of 0.40% (forty one-hundredths of one percent) plus the yield on treasury
securities at constant maturity under the heading “Week Ending” published in
the Statistical Release (as defined herein) under the caption “Treasury
Constant Maturities” for the maturity (rounded to the nearest month)
corresponding to the remaining life to maturity (which, in the case of
maturities corresponding to the principal and interest due on the Notes at
their maturity, shall be deemed to be July
15, 2017), as of the payment date of the principal being redeemed or
paid.  If no maturity exactly corresponds
to such maturity, yields for the two published maturities most closely
corresponding to such maturity shall be calculated pursuant to the immediately
preceding sentence and the Reinvestment Rate shall be interpolated or
extrapolated from such yields on a straight-line basis, rounding in each of
such relevant periods to the nearest month. 
For purposes of calculating the Reinvestment Rate, the most recent
Statistical Release published prior to the date of determination of the
Make-Whole Amount shall be used.


As
used herein the term “Statistical Release” means the statistical release
designated “H.15(519)” or any successor publication which is published weekly
by the Federal Reserve System and which establishes yields on actively traded
United States government securities adjusted to constant maturities or, if such
statistical release is not published at the time of any determination under the
Supplemental Indenture, then any publicly available source of similar market
data which shall be designated by the Company.


5.             Mandatory Redemption.  The Company shall not be required to make
sinking fund or redemption payments with respect to the Notes.


6.             Notice of
Redemption.  Notice of redemption
shall be mailed at least 30 days but not more than 60 days before the
Redemption Date to each Holder of Notes to be redeemed at its registered
address.  Notes may be redeemed in part
but only in whole multiples of $1,000, unless all of the Notes held by a Holder
are to be redeemed.  On and after the
Redemption Date, interest ceases to accrue on Notes or portions of them called
for redemption.


 


 


A-3

















7.             Denominations,
Transfer, Exchange.  The Notes are in
registered form without coupons in denominations of $1,000 and integral
multiples of $1,000 in excess thereof. 
The transfer of Notes may be registered and Notes may be exchanged as
provided in the Indenture.  The Security
Registrar and the Trustee may require a Holder, among other things, to furnish
appropriate endorsements and transfer documents and to pay any taxes and fees
required by law or permitted by the Indenture. 
The Security Registrar need not exchange or register the transfer of any
Note or portion of a Note selected for redemption.  Also, it need not exchange or register the
transfer of any Notes for a period of 15 days before the mailing of a notice of
redemption of Notes, or during the period between a record date and the
corresponding Interest Payment Date.


8.             Defaults and
Remedies.  In case an Event of
Default (as defined in the Indenture) with respect to the Notes shall have
occurred and be continuing, the principal hereof may be declared, and upon such
declaration shall become, due and payable, in the manner, with the effect and
subject to the provisions provided in the Indenture.


9.             Actions of
Holders.  The Indenture contains
provisions permitting the Holders of not less than a majority of the aggregate
principal amount of the outstanding Notes, subject to certain exceptions as
provided in the Indenture, on behalf of the Holders of all such Notes at a
meeting duly called and held as provided in the Indenture, to make, give or
take any request, demand, authorization, direction, notice, consent, waiver or
other action provided in the Indenture to be made, given or taken by the
Holders of the Notes, including without limitation, waiving (a) compliance
by the Company with certain provisions of the Indenture, and (b) certain
past defaults under the Indenture and their consequences.  Any resolution passed or decision taken at
any meeting of the Holders of the Notes in accordance with the provisions of
the Indenture shall be conclusive and binding upon such Holders and upon all
future Holders of this Note and other Notes issued upon the registration of
transfer hereof or in exchange heretofore or in lieu hereof.


10.           Persons Deemed
Owners.  The Company, the Trustee,
and any agent of the Company or the Trustee may deem and treat the Person in
whose name this Note is registered on the Security Register as its absolute
owner for all purposes.


11.           Authentication.  This Note shall not be valid until
authenticated by the manual signature of the Trustee or an authenticating
agent.


12.           Governing Law.
THE INTERNAL LAW OF THE COMMONWEALTH OF MASSACHUSETTS SHALL GOVERN AND BE USED
TO CONSTRUE THE INDENTURE AND THE NOTES.


13.           No Personal
Liability.  THE AMENDED AND RESTATED
DECLARATION OF TRUST ESTABLISHING THE COMPANY, DATED JULY 1, 1994, A COPY OF
WHICH, TOGETHER WITH ALL AMENDMENTS AND SUPPLEMENTS THERETO, IS DULY FILED IN
THE OFFICE OF THE STATE DEPARTMENT OF ASSESSMENTS AND TAXATION OF MARYLAND,
PROVIDES THAT THE NAME “HRPT PROPERTIES TRUST” REFERS TO THE TRUSTEES UNDER THE
DECLARATION OF TRUST, AS SO AMENDED AND SUPPLEMENTED, COLLECTIVELY AS TRUSTEES,
BUT


 


 


A-4

















NOT
INDIVIDUALLY OR PERSONALLY, AND THAT NO TRUSTEE, OFFICER, SHAREHOLDER, EMPLOYEE
OR AGENT OF THE COMPANY SHALL BE HELD TO ANY PERSONAL LIABILITY, JOINTLY OR
SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST THE COMPANY. ALL PERSONS
DEALING WITH THE COMPANY, IN ANY WAY, SHALL LOOK ONLY TO THE ASSETS OF THE
COMPANY FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY OBLIGATION.


The Company will furnish
to any Holder upon written request and without charge a copy of the
Indenture.  Request may be made to:


	
   

  	
  HRPT Properties Trust

  	
   

  
	
   

  	
  400 Centre Street

  	
   

  
	
   

  	
  Newton, MA 02458

  	
   

  
	
   

  	
  Telecopier No.: (617) 332-2261

  	
   

  
	
   

  	
  Attention: President

  	
   

  



 


or such other address as
the Company may specify pursuant to the Indenture.


 


A-5

















ASSIGNMENT
FORM


To
assign this Note, fill in the form below:


[I] [We] assign
and transfer this Note to________________________________________________________


_______________________________________________
[Print or type assignee’s name, address and zip code]


_____________________________________
[Insert assignee’s soc. sec. or tax I.D. no.]
and irrevocably appoint


_____________________________ to transfer this Note on
the books of the Company. The agent may substitute


another to act for
him.


Date: ______________________


	
   

  	
  Your Signature:

  	
   

  
	
   

  	
  [Sign exactly as your name appears on the face of
  this Note]

  



 


	
  Signature Guarantee:

  
	
   

  
	
   

  	
   

  
	
  [The signature must be guaranteed by

  
	
  an officer of a participant in a recognized

  
	
  signature guarantee program. Notarized

  
	
  or witnessed signatures are not acceptable.]