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Filed Pursuant to Rule 424(b)(5)
Registration No. 333-56051

P R O S P E C T U S    S U P P L E M E N T

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(To prospectus dated June 15, 1998)

11,000,000 Shares

HRPT Properties Trust

8³/4% Series B Cumulative Redeemable Preferred Shares
(Liquidation Preference $25 Per Share)

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        Distributions on the Series B Preferred Shares will be cumulative from (but excluding) the date of original issue and payable quarterly, beginning on November 15, 2002, at the rate of 8³/4% of the liquidation preference per annum, or $2.1875 per Series B Preferred Share per annum.

        The Series B Preferred Shares are not redeemable until September 12, 2007, after which we may redeem the shares at $25.00 each, plus any accrued and unpaid distributions to and including the date of redemption. The Series B Preferred Shares have no maturity date and will remain outstanding indefinitely unless redeemed.

        We have filed an application to list the Series B Preferred Shares on the New York Stock Exchange. If the application is approved, trading of the Series B Preferred Shares on the NYSE is expected to begin within 30 days after the date of initial delivery of the Series B Preferred Shares.

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(1)

Plus accrued distributions, if any, from (but excluding) the date of original issue.

        The underwriters may also purchase up to an additional 1,650,000 Series B Preferred Shares from us at the public offering price, less the underwriting discount, within 30 days from the date of this prospectus supplement to cover over allotments.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        The Series B Preferred Shares will be ready for delivery through the facilities of The Depository Trust Company on or about September 12, 2002.

Joint Book-Running Managers
Merrill Lynch & Co.		UBS Warburg
A.G. Edwards & Sons, Inc.	Legg Mason Wood Walker Incorporated	Morgan Stanley
Prudential Securities		Raymond James
RBC Capital Markets		Wachovia Securities

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The date of this prospectus supplement is September 6, 2002.

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TABLE OF CONTENTS

Prospectus Supplement

		Page
Prospectus Supplement Summary		S-1
Use of Proceeds		S-4
Capitalization		S-4
Recent Developments		S-5
The Company		S-6
Ratio of Earnings to Fixed Charges		S-8
Description of the Series B Preferred Shares		S-8
Federal Income Tax and ERISA Considerations		S-13
Underwriting		S-15
Legal Matters		S-17
Experts		S-17
Incorporation of Certain Information by Reference		S-17
Where You Can Find More Information		S-18
Forward-Looking Statements		S-19
Prospectus
Available Information		ii
Incorporation of Certain Documents by Reference		ii
The Company		1
Use of Proceeds		1
Ratio of Earnings to Fixed Charges		1
Description of Debt Securities		1
Description of Shares		11
Description of Preferred Shares		11
Description of Depositary Shares		17
Description of Warrants		20
Description of Convertible Subordinated Debentures		20
Limitation of Liability; Shareholder Liability		21
Redemption; Business Combinations and Control Share Acquisitions		21
Plan of Distribution		24
Legal Matters		25
Experts		25

        In this prospectus supplement, the terms "we", "us" or "HRP" include HRPT Properties Trust and its consolidated subsidiaries.

        In presenting "as adjusted" information in this prospectus supplement, we have assumed that this offering has been completed and that we have applied some of the net proceeds to repay amounts outstanding on our revolving bank credit facility and our outstanding 6.75% senior notes, and that the remainder has been deposited in interest bearing cash accounts. Unless otherwise stated we have assumed throughout this prospectus supplement that the underwriters' over allotment option is not exercised.

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        You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not, and the underwriters have not, authorized any person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference is accurate only as of their respective dates or on other dates which are specified in those documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

(i)

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PROSPECTUS SUPPLEMENT SUMMARY

        This summary may not contain all of the information that is important to you. You should carefully read this entire prospectus supplement and the accompanying prospectus. You should also read the documents we have referred you to in "Incorporation of Certain Information by Reference."

The Company

        We are a real estate investment trust ("REIT") that owns office properties. As of September 6, 2002, we own 202 properties costing $2.8 billion located in 27 states and the District of Columbia. Our unsecured debt securities have been investment grade rated since 1994. The following table and chart present our capitalization as of June 30, 2002, as adjusted (in millions):

HRP Capitalization

						Percent of Total
Secured debt			$	338		12	%
Unsecured debt, less cash				538		19	%
	Total debt, net of cash		$	876		31	%
Preferred shares			$	459		17	%
Common shares				1,451		52	%
	Total equity		$	1,910		69	%

        Our ability to pay distributions on our preferred shares, including the Series B Preferred Shares, will depend primarily upon our receipt of rents from tenants. We have focused our acquisitions on office properties which are leased to government agencies and to tenants which are in medical related businesses. We believe that these tenants are less affected by cyclical economic conditions, are more likely to sign long term leases and are more likely to renew upon lease expirations than office tenants engaged in other activities. When leasing to tenants in other businesses we try to focus on tenants who have strong credit qualities. Our largest tenant is the U.S. Government which is responsible for about 20% of our total rents. About 73% of our rents come from leases that expire in 2005 and after. The following chart and table present data as of June 30, 2002, adjusted for leasing transactions described in "Recent Developments."

HRP Tenants

        

HRP Lease Expirations

Year		Percent of Total Rents
2002		4	%
2003		12	%
2004		11	%
2005 and after		73	%

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*

Includes tenants which are investment grade rated, subsidiaries of investment grade rated companies and large professional services businesses, such as law and accounting firms, which are generally considered to be strong credit tenants.

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Principal Place of Business

        We are organized as a Maryland real estate investment trust. Our principal place of business is 400 Centre Street, Newton, Massachusetts 02458, and our telephone number is (617) 332-3990.

The Offering

        The following is a brief summary of certain terms of this offering. For a more complete description of the terms of the Series B Preferred Shares, see "Description of the Series B Preferred Shares" in this prospectus supplement and "Description of Preferred Shares" in the accompanying prospectus.

Issuer		HRPT Properties Trust.
Securities Offered		11,000,000 shares of 83/4% Series B Cumulative Redeemable Preferred Shares. The underwriters have an option to purchase up to 1,650,000 additional shares of Series B Preferred Shares from us to cover over allotments, if any.
Distributions		Investors will be entitled to receive cumulative cash distributions on the Series B Preferred Shares at a rate of 83/4% per annum of the $25.00 per share liquidation preference (equivalent to $2.1875 per annum per share). Beginning on November 15, 2002, distributions on the Series B Preferred Shares will be payable quarterly in arrears on the fifteenth day of each February, May, August and November or, if not a business day, the next business day. Distributions on the Series B Preferred Shares will be cumulative from (but excluding) the date of original issuance, which is expected to be September 12, 2002.
Optional Redemption		We may not redeem the Series B Preferred Shares prior to September 12, 2007, except in limited circumstances relating to our continuing qualification as a REIT. On and after September 12, 2007, we may, at our option, redeem the Series B Preferred Shares, in whole or from time to time in part, by payment of $25.00 per share, plus any accrued and unpaid distributions to and including the date of redemption. Any partial redemption of the Series B Preferred Shares will be on a pro rata basis.
No Maturity		The Series B Preferred Shares have no maturity date and we are not required to redeem the Series B Preferred Shares. Accordingly, the Series B Preferred Shares will remain outstanding indefinitely unless we decide to redeem them. We are not required to set aside funds to redeem the Series B Preferred Shares.
Liquidation Preference		If we liquidate, dissolve or wind up, holders of the Series B Preferred Shares will have the right to receive $25.00 per share, plus accrued and unpaid distributions to and including the date of payment, before any payments are made to the holders of our common shares and any other shares of beneficial interest ranking junior to the Series B Preferred Shares as to liquidation rights. The rights of the holders of the Series B Preferred Shares to receive their liquidation preference will be subject to the proportionate rights of each other series or class of our shares ranked on a parity with the Series B Preferred Shares, including our Series A preferred shares.

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Ranking		The Series B Preferred Shares rank senior to our common shares and on a parity with our Series A preferred shares with respect to the payment of distributions and the distribution of assets in the event of our liquidation, dissolution or winding up.
Voting Rights		Holders of any series of our preferred shares, including the Series B Preferred Shares generally have no voting rights. However, if we do not pay distributions on our preferred shares for six or more quarterly periods (whether or not consecutive), the holders of the Series B Preferred Shares, voting together with the holders of any other series of our preferred shares which has similar voting rights, including our Series A preferred shares, will be entitled to vote for the election of two additional trustees to serve on our board of trustees until we pay all distributions which we owe on our preferred shares. In addition, the affirmative vote of the holders of at least two-thirds of the Series B Preferred Shares is required for us to authorize, create or increase capital shares ranking senior to the Series B Preferred Shares or to amend our declaration of trust in a manner that materially and adversely affects the rights of the holders of the Series B Preferred Shares.
Listing		We have filed an application to list the Series B Preferred Shares on the NYSE. If the application is approved, trading of the Series B Preferred Shares on the NYSE is expected to begin within 30 days after the date of initial delivery of the Series B Preferred Shares.
Restrictions on Ownership and Transfer		Our declaration of trust and articles supplementary contain provisions that limit to 8.5% the percentage ownership of our equity in the aggregate and by series, including the Series B Preferred Shares, by any one person or group of affiliated persons. Our articles supplementary for the Series B Preferred Shares allow our board of trustees to waive this ownership limit. We may prevent any proposed transfer of our capital shares, including the Series B Preferred Shares, which would jeopardize our status as a REIT. We have the right to purchase any shares, including the Series B Preferred Shares, or refuse to transfer or issue shares to a person whose acquisition of shares would result in ownership in excess of the 8.5% limit. Any transfer of shares that would result in our disqualification as a REIT or in a person's exceeding this ownership limit which is not waived by us is deemed void ab initio. We may repurchase any shares necessary to maintain our REIT status.
Conversion		The Series B Preferred Shares are not convertible into or exchangeable for any other securities or property.
Use of Proceeds		We estimate that our net proceeds from this offering will be about $265.8 million. We presently intend to use some of the net proceeds from this offering to repay $122 million outstanding on our revolving bank credit facility and to redeem all of our outstanding 6.75% senior notes at par ($128.3 million) which we have called for redemption on or about October 7, 2002. The remainder of the proceeds will be used for general business purposes.

S-3

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USE OF PROCEEDS

        We estimate that the net proceeds of this offering, after deducting the underwriting discount and other offering expenses, will be about $265.8 million. We presently intend to use some of the net proceeds of this offering to repay all amounts outstanding on our revolving bank credit facility and to redeem all of our outstanding 6.75% senior notes at par ($128.3 million) which we have called for redemption on or about October 7, 2002. The remainder of the proceeds will be used either to repay additional debt, to purchase additional properties or for other general business purposes. As of September 6, 2002, we had $122 million outstanding on our revolving bank credit facility bearing interest at 2.6% per annum. Our revolving bank credit facility matures in 2005. If, prior to October 7, 2002, proceeds from this offering are used to purchase additional properties or for other general business purposes, we may use our revolving bank credit facility to redeem our 6.75% senior notes. Until we use the proceeds from this offering, they may be deposited in interest bearing cash accounts or invested in short-term securities, including securities that may not be investment grade rated.

CAPITALIZATION

        The following table sets forth our capitalization as of June 30, 2002, and as adjusted assuming completion of this offering. The following table assumes the net proceeds of this offering will be used to repay amounts outstanding on our revolving bank credit facility and to redeem all of our outstanding 6.75% senior notes and that the remainder will be deposited in interest bearing cash accounts.

					June 30, 2002
					Actual			As Adjusted
					(amounts in thousands, except share and per share amounts) (unaudited)
Cash					$	13,473		$	106,260
Debt:
	Revolving bank credit facility				$	23,000		$	—
	Senior notes payable, net					794,464			644,464
	Mortgage notes payable, net					337,773			337,773
			Total debt			1,155,237			982,237
Shareholders' equity:
	Preferred shares of beneficial interest, par value $0.01 per share;
			Series A, 8,000,000 issued and outstanding			193,086			193,086
			Series B, none issued and 11,000,000 issued and outstanding, as adjusted			—			265,787
	Common shares of beneficial interest, par value $0.01 per share;     128,810,247 issued and outstanding					1,288			1,288
	Additional paid in capital					1,945,623			1,945,623
	Cumulative net income					951,728			951,728
	Cumulative common distributions					(1,424,025	)		(1,424,025	)
	Cumulative preferred distributions					(24,194	)		(24,194	)
	Unrealized holding gains on investments					424			424
			Total shareholders' equity			1,643,930			1,909,717
			Total capitalization		$	2,799,167		$	2,891,954

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RECENT DEVELOPMENTS

Leasing

        During the twelve months ended August 31, 2002, we entered new leases for about 2 million square feet of office space. On average, rents under these new leases are about 12% higher than rents previously charged for the same space. The largest of these new leases is to the U.S. Government for 340,000 square feet of space to be used by various agencies connected with homeland security. During the same period our property occupancy declined from 94% to 92%. Property occupancy includes all space under lease and space which is being fitted out or otherwise prepared for occupancy pursuant to signed leases.

        We believe the increases in rents we have experienced in the past year are a consequence of the fact that many of our expiring leases were entered several years ago at rents below current rates. The decline in occupancy we have experienced in the past year is a result of slowing economic activity in the U.S., particularly in certain areas where we own property such as Austin, Texas.

Investments

        During the twelve months ended August 31, 2002, we acquired 15 office properties containing 1.6 million square feet of space for $203 million, including closing costs. The largest of these acquisitions is a 532,000 square foot office property which is 100% leased to the U.S. Internal Revenue Service through 2011, which we purchased for $73 million. In combination, these properties are 96% occupied and their combined annual revenues, net of estimated operating expenses excluding depreciation, yielded 11% on our investment at the time these properties were acquired.

        In the normal course of business we regularly evaluate opportunities to acquire properties. As of September 6, 2002, we were engaged in multiple negotiations to purchase office properties for aggregate purchase prices of about $330 million. Our acquisition of these office properties is generally subject to further negotiations, execution of contracts and closing conditions customary in real estate transactions. No assurances can be given as to when or if any of these office properties will be acquired. We may also acquire additional properties involving material amounts in the future.

Financing

        In March 2002 we redeemed, at par plus a premium, all $160 million of our 6.875% senior unsecured notes due August 2002. This redemption was funded by borrowings on our $425 million revolving unsecured bank credit facility.

        In April 2002 we issued $200 million of 6.95% senior unsecured notes due 2012. The net proceeds of this issuance ($197 million) were used to repay amounts then outstanding on our revolving bank credit facility and for general business purposes including new investments.

        In July 2002 we repurchased $21.7 million of our 6.75% senior notes due December 2002. Our purchase price for these notes, 100.48% of par, or $21.8 million, was funded with cash on hand and borrowings on our revolving bank credit facility. We have called the $128.3 million balance of this note issuance for redemption at par on or about October 7, 2002.

        We have one other series of notes outstanding which currently may be prepaid at par: $90 million of 7.875% senior notes due 2009. Our decision as to whether to prepay these notes will depend upon available financing and our projected capital needs for investments or other purposes.

        In July 2002 we filed an application with the SEC to sell some of our own common shares and some common shares of our former subsidiaries, Hospitality Properties Trust and Senior Housing Properties Trust, which we own to a new mutual fund which may be organized by our investment and property manager, Reit Management & Research LLC. The SEC review process is expected to take several months. If this application is approved, we will decide whether to proceed with these sales depending upon market conditions at that time, particularly the market value of the shares to be sold

S-5

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and uses of proceeds available to us. We can provide no assurance that this source of financing will be available to us.

THE COMPANY

        We are a REIT that owns and leases office properties. As of September 6, 2002, we own 202 properties with 21 million square feet of space costing $2.8 billion. These properties are located in 27 states and the District of Columbia. We own a nationwide portfolio of office properties with over 4 million square feet of space which are leased to the U.S. Government and other government entities. We also own a nationwide portfolio of office properties with over 4 million square feet leased to tenants in medical related businesses. We have focused our acquisitions on government and medical tenanted properties because we believe those tenants are less affected by cyclical economic conditions, are more likely to sign long term leases and are more likely to renew their tenancies upon lease expirations than tenants in other businesses.

        In selected areas we have expanded our investments to include office properties leased to commercial tenants generally. Whenever we have expanded by acquiring office properties leased to commercial tenants generally we have tried to purchase high quality properties leased to strong credit quality tenants.

States In Which HRP Properties Are Located

        

        As of June 30, 2002, and including leasing transactions described in "Recent Developments," the market areas from which 5% or more of our annual rents are received are as follows (in millions):

Market Areas From Which HRP Receives More Than 5% Of Its Total Rents

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        Our business plan to invest nationwide in government and medical tenanted properties and to concentrate our general commercial office properties in selected areas has resulted in what we believe is stable and diversified rental income. The following tables show our sources of rents, our schedule of lease expirations and a listing of all our tenants responsible for 1% or more of our gross rents as of June 30, 2002 (in millions). These tables include leasing transactions described in "Recent Developments."

HRP Tenants

			Rent			Percent of Total Rent
U.S. Government			$	83.9		20%
Other government				11.1		3%
	Subtotal government tenants			95.0		23%
Medical tenants				110.5		26%
Other high credit quality tenants *				101.4		24%
	Subtotal government, medical and other strong credit tenants			306.9		73%
Other tenants				112.6		27%
	Total		$	419.5		100%

HRP Lease Expirations

Year		Rent			Percent of Total Rent
2002		$	16.5		4%
2003			50.5		12%
2004			47.0		11%
2005			49.2		12%
2006			41.4		10%
2007			42.3		10%
2008			18.3		4%
2009			11.2		3%
2010			10.2		2%
2011 and after			132.9		32%
Total		$	419.5		100%

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*

Includes tenants which are investment grade rated, subsidiaries of investment grade rated companies and large professional services businesses, such as law and accounting firms, which are generally considered to be strong credit tenants.

HRP Tenants Responsible For More Than 1% of Rents

S-7

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        In addition to our office properties, we also own minority equity investments in two former subsidiaries which are separately listed on the NYSE: four million common shares of Hospitality Properties Trust, a REIT which owns hotels; and 12.8 million common shares of Senior Housing Properties Trust, a REIT which owns senior living properties. The book value of our investment in Hospitality Properties Trust and Senior Housing Properties Trust was $99 million and $169 million, respectively, at June 30, 2002. The market value of our investment in Hospitality Properties Trust and Senior Housing Properties Trust was $138.8 million and $158.8 million, respectively, at September 6, 2002. Our unsecured debt securities have been investment grade rated since 1994.

RATIO OF EARNINGS TO FIXED CHARGES

        Our consolidated ratio of earnings to fixed charges was 2.2x and 2.3x for the six months ended June 30, 2002 and 2001, respectively, and 2.3x, 2.3x, 2.5x, 3.2x and 3.8x for the years ended December 31, 2001, 2000, 1999, 1998 and 1997, respectively. Our consolidated ratio of earnings to combined fixed charges and preferred distributions was 1.8x and 2.0x for the six months ended June 30, 2002 and 2001, respectively, and 1.9x, 2.3x, 2.5x, 3.2x and 3.8x for the years ended December 31, 2001, 2000, 1999, 1998 and 1997, respectively. Assuming completion of this offering and application of the net proceeds as described in "Capitalization," our pro forma ratio of earnings to fixed charges would be 2.6x and 2.6x and our pro forma ratio of earnings to combined fixed charges and preferred distributions would be 1.7x and 1.7x, each for the six months ended June 30, 2002, and the year ended December 31, 2001, respectively. For this purpose, earnings have been calculated by subtracting capitalized interest and adding fixed charges and distributions from equity investments to income before equity in earnings of equity investments and extraordinary items. Fixed charges consist of interest costs, whether expensed or capitalized, the interest component of rental expense, if any, and amortization of debt discounts and deferred financing costs, whether expensed or capitalized. The ratio of earnings to fixed charges and preferred distributions was computed by dividing our earnings by fixed charges and preferred distributions.

DESCRIPTION OF THE SERIES B PREFERRED SHARES

        This description of the Series B Preferred Shares supplements the description of the general terms and provisions of our shares of beneficial interest, including preferred shares, in the accompanying prospectus. You should consult that general description for further information.

General

        We are currently authorized to issue up to 50,000,000 preferred shares in one or more series. Our declaration of trust and Maryland law allow our board of trustees to increase the authorized number of our preferred shares without shareholder approval. Each series of our preferred shares has the designations, powers, preferences, rights, qualifications, limitations or restrictions as Maryland law permits and our board of trustees determines by adoption of applicable articles supplementary to our declaration of trust. As of September 6, 2002, there are 8,000,000 Series A preferred shares outstanding (liquidation preference $25 per share) the holders of which have rights substantially identical to the rights of holders of the Series B Preferred Shares offered hereby, except as to distribution rate and payment dates and commencement date of redeemability.

        Prior to completing this offering, we will adopt articles supplementary for the Series B Preferred Shares. You may obtain a complete copy of the articles supplementary describing the Series B Preferred Shares by contacting us. The articles supplementary will initially authorize 12,650,000 Series B Preferred Shares. Our board of trustees may authorize additional Series B Preferred Shares from time to time.

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        The transfer agent, registrar and distribution disbursing agent for the Series B Preferred Shares is EquiServe Trust Company, N.A.

        We have filed an application to list the Series B Preferred Shares on the NYSE. If the application is approved, trading of the Series B Preferred Shares on the NYSE is expected to begin within 30 days after the date of initial delivery of the Series B Preferred Shares.

        The certificates evidencing the Series B Preferred Shares initially will be issued in the form of temporary certificates. Holders of temporary certificates will be entitled to exchange them for definitive certificates as soon as the definitive certificates are available. We anticipate that definitive certificates will be available within 150 days after the date of initial delivery of the Series B Preferred Shares.

Distributions

        Holders of the Series B Preferred Shares will be entitled to receive, when and as authorized by our board of trustees, out of funds legally available for the payment of distributions, cumulative cash distributions at the rate of 8³/4% of the liquidation preference per annum. Distributions on the Series B Preferred Shares will accrue and be cumulative from (but excluding) the date of original issue and will be payable quarterly in arrears on the fifteenth day of each February, May, August and November or, if not a business day, the next business day. The first distribution on the Series B Preferred Shares will be paid on November 15, 2002. Distributions payable on the Series B Preferred Shares for any partial period will be computed on the basis of a 360-day year consisting of twelve 30-day months. We will pay distributions to holders of record as they appear in our share records at the close of business on the applicable record date designated by our board of trustees for the payment of distributions that is not more than 60 nor less than 10 days prior to the distribution payment date.

        We will not authorize or pay any distributions on the Series B Preferred Shares or set aside funds for the payment of distributions if restricted or prohibited by law, or if the terms of any of our agreements, including agreements relating to our indebtedness or our other series of preferred shares, prohibit that authorization, payment or setting aside of funds or provide that the authorization, payment or setting aside of funds is a breach of or a default under that agreement. We are, and may in the future become, a party to agreements which restrict or prevent the payment of distributions on, or the purchase or redemption of, shares. These restrictions may include indirect covenants which require us to maintain specified levels of net worth or assets. We do not believe that these restrictions currently have any adverse impact on our ability to pay distributions on the Series B Preferred Shares.

        Notwithstanding the foregoing, distributions on the Series B Preferred Shares will accrue whether or not we have earnings, whether or not there are funds legally available for the payment of distributions and whether or not distributions are authorized. Accrued but unpaid distributions on the Series B Preferred Shares will not bear interest, and holders of the Series B Preferred Shares will not be entitled to any distributions in excess of full cumulative distributions as described above. All of our distributions on the Series B Preferred Shares, including any capital gain distributions, will be credited first to the earliest accrued and unpaid distribution due.

        We will not declare or pay any distributions, or set aside any funds for the payment of distributions, on common shares or other shares that rank junior to the Series B Preferred Shares, or redeem or otherwise acquire common shares or other junior shares, unless we also have declared and either paid or set aside for payment the full cumulative distributions on the Series B Preferred Shares and on all our other series of preferred shares ranking senior to or on a parity with the Series B Preferred Shares, for the current and all past dividend periods. In addition to the exceptions described on page 13 of the accompanying prospectus, this restriction will not limit our redemption or other acquisition of shares under incentive, benefit or share purchase plans for officers, trustees or employees or others performing or providing similar services, for the purposes of enforcing restrictions upon ownership and transfer of our equity securities contained in our declaration of trust, for the purpose of

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preserving our status as a REIT or our redemption or other acquisition of rights issued under our shareholder rights plan or any successor plan we adopt.

        We will not authorize the full cumulative distributions on any preferred shares unless we have authorized those distributions as are accrued on all of our outstanding preferred shares which are of parity series. If we do not declare and either pay or set aside for payment the full cumulative distributions on the Series B Preferred Shares and all shares that rank on a parity with Series B Preferred Shares, including our Series A preferred shares, the amount which we have declared will be allocated pro rata to the Series B Preferred Shares and to each parity series of shares, including our Series A preferred shares, so that the amount declared for each Series B Preferred Share and for each share of each parity series is proportionate to the accrued and unpaid distributions on those shares.

Redemption

        We may not redeem the Series B Preferred Shares prior to September 12, 2007, except as described below under "—Restrictions on Ownership and Transfer." On and after September 12, 2007, at our option upon not less than 30 nor more than 60 days written notice, we may redeem the Series B Preferred Shares, in whole or in part, at any time or from time to time, at a redemption price of $25.00 per share, plus all accrued and unpaid distributions through the date fixed for redemption. Our optional redemption rights for preferred shares are exercisable separately within each of our series of preferred shares.

        We may give notice of redemption by mail to each holder of record of Series B Preferred Shares at the address shown on our share transfer books. A failure to give notice of redemption or any defect in the notice or in its mailing will not affect the validity of the redemption of any Series B Preferred Shares except as to the holder to whom notice was defective. Each notice will state the following:

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the redemption date;



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the redemption price;



•

the number of Series B Preferred Shares to be redeemed;



•

the place where the certificates for the Series B Preferred Shares are to be surrendered for payment; and



•

that distributions on the shares to be redeemed will cease to accrue on the redemption date.

        If we redeem fewer than all of the Series B Preferred Shares, the notice of redemption mailed to each shareholder will also specify the number of Series B Preferred Shares that we will redeem from each shareholder. In this case, we will determine the number of Series B Preferred Shares to be redeemed on a pro rata basis, by lot or by any other equitable method we may choose. Unless the full cumulative distributions on all Series B Preferred Shares have been paid or set aside we generally may not redeem any Series B Preferred Shares unless we redeem all of the Series B Preferred Shares.

        If we have given a notice of redemption and have set aside sufficient funds for the redemption in trust for the benefit of the holders of the Series B Preferred Shares called for redemption, then, from and after the redemption date, those Series B Preferred Shares will be treated as no longer outstanding, no further distributions will accrue and all other rights of the holders of those Series B Preferred Shares will terminate. The holders of those Series B Preferred Shares will retain their right to receive the redemption price for their shares and any accrued and unpaid distributions through the redemption date.

        The holders of Series B Preferred Shares at the close of business on a distribution record date will be entitled to receive the distribution payable with respect to the Series B Preferred Shares on the corresponding payment date notwithstanding the redemption of the Series B Preferred Shares between

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such record date and the corresponding payment date. Except as provided above, we will make no payment or allowance for unpaid distributions, whether or not in arrears, on Series B Preferred Shares to be redeemed.

        The Series B Preferred Shares have no stated maturity and will not be subject to any sinking fund or mandatory redemption provisions, except as provided under "—Restrictions on Ownership and Transfer" below.

        Subject to applicable law, we may purchase Series B Preferred Shares in the open market, by tender or by private agreement. Any Series B Preferred Shares that we reacquire will be returned to the status of authorized but unissued Series B Preferred Shares, unless determined otherwise by our board of trustees.

Liquidation Rights

        In the event of our liquidation, the holders of the Series B Preferred Shares will be entitled to be paid out of our assets legally available for distribution to our shareholders liquidating distributions in cash or property at fair market value as determined by our board of trustees equal to a liquidation preference of $25.00 per share, plus any accrued and unpaid distributions through and including the date of the payment. The holders of Series B Preferred Shares will be entitled to receive this liquidating distribution before we distribute any assets to holders of our common shares or any other shares of beneficial interest that rank junior to the Series B Preferred Shares. The rights of holders of Series B Preferred Shares to receive their liquidation preference would be subject to the proportionate rights of each parity series, including our Series A preferred shares, and the preferential rights of the holders of any series of shares which is senior to the Series B Preferred Shares. After payment of the full amount of the liquidating distribution to which they are entitled, the holders of Series B Preferred Shares will have no right or claim to any of our remaining assets. If we consolidate or merge with any other entity, sell, lease, transfer or convey all or substantially all of our property or business, or engage in a statutory share exchange, we will not be deemed to have liquidated.

Ranking

        The Series B Preferred Shares will rank senior to our common shares and to any other of our equity securities that by their terms rank junior to the Series B Preferred Shares with respect to payments of distributions or amounts upon our liquidation, dissolution or winding up. The Series B Preferred Shares will rank on a parity with our existing Series A preferred shares and with other series of our preferred shares or other equity securities that we may later authorize or issue and that by their terms are on a parity with the Series B Preferred Shares. The Series B Preferred Shares will rank junior to any equity securities that we may later authorize or issue and that by their terms ranks senior to the Series B Preferred Shares. Any convertible debt securities that we may issue are not considered to be equity securities for these purposes.

Voting Rights

        Holders of Series B Preferred Shares will have no voting rights, except as follows:

•

If distributions on our preferred shares are due for six or more quarterly periods and remain unpaid, whether or not these quarterly periods are consecutive, holders of the Series B Preferred Shares, voting together with all other series of preferred shares which have similar voting rights, including our Series A preferred shares, will be entitled to vote for the election of two additional trustees to serve on our board of trustees until all distribution arrearages have been paid. These voting rights, to the extent not inconsistent with the preceding sentence, are described more fully on pages 15 and 16 of the accompanying prospectus.

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•

In addition, the affirmative vote of the holders of at least two-thirds of the Series B Preferred Shares is required for us to authorize, create or increase our capital shares ranking senior to the outstanding Series B Preferred Shares or to amend our declaration of trust in a manner that materially and adversely affects the rights of the holders of the Series B Preferred Shares. These special voting rights, to the extent not inconsistent with the preceding sentence, are described more fully on pages 15 and 16 of the accompanying prospectus.

        In any matter in which the Series B Preferred Shares are entitled to vote, each Series B Preferred Share will be entitled to one vote. If the holders of Series B Preferred Shares and another series of preferred shares are entitled to vote together as a single class on any matter, the Series B Preferred Shares and the shares of the other series will have one vote for each $25.00 of liquidation preference.

Restrictions on Ownership and Transfer

        The articles supplementary for the Series B Preferred Shares provide that an 8.5% ownership limitation and excess share provisions described on page 21 of the accompanying prospectus apply both to ownership of all our shares of beneficial interest in the aggregate and to ownership of Series B Preferred Shares as a separate class. Our board of trustees may (i) elect to purchase any shares owned by a person or group of affiliated persons in excess of the ownership limitations or (ii) refuse to transfer or issue shares to a person if an acquisition of shares by such person or group would result in such person or group exceeding these ownership limits. Any transfer of shares that would result in our disqualification as a REIT or in a person or group exceeding ownership limits is deemed void as of the date of such transfer. We may repurchase any shares necessary to maintain our status as a REIT.

        In addition, the articles supplementary provide that the outstanding Series B Preferred Shares cannot be held by fewer than 120 persons. To enforce this provision, we have the right to refuse to transfer Series B Preferred Shares which would cause there to be fewer than 120 holders thereof at any time, or to redeem such shares for a price equal to $25.00 per share, plus any accrued and unpaid distributions through the redemption date.

        Our board of trustees has the right to waive ownership limitations and excess share provisions of the articles supplementary.

Conversion Rights

        The Series B Preferred Shares are not convertible into or exchangeable for any property or other securities.

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FEDERAL INCOME TAX AND ERISA CONSIDERATIONS

        The following summary of United States federal income tax considerations and Employee Retirement Income Security Act of 1974, as amended ("ERISA"), considerations relating to the acquisition, ownership and disposition of the Series B Preferred Shares supplements and updates the more detailed description of these matters in our Annual Report on Form 10-K for the year ended December 31, 2001, which we incorporate in this prospectus supplement by reference. Sullivan & Worcester LLP, Boston, Massachusetts, has rendered a legal opinion that the discussions in this section and in the sections of our 2001 Annual Report captioned "Federal Income Tax Considerations" and "ERISA Plans, Keogh Plans and Individual Retirement Accounts" are accurate in all material respects and, taken together, fairly summarize the federal income tax and ERISA issues discussed in those sections, and the opinions of counsel referred to in those sections represent Sullivan & Worcester LLP's opinions on those subjects. Specifically, subject to qualifications and assumptions contained in its opinion and in our 2001 Annual Report, Sullivan & Worcester LLP has given opinions to the effect (1) that we have been organized and have qualified as a REIT under the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"), for our 1987 through 2001 taxable years, and that our current investments and plan of operation will enable us to continue to meet the requirements for qualification and taxation as a REIT under the Internal Revenue Code, and (2) that under the "plan assets" regulations promulgated by the Department of Labor under ERISA, our assets will not be deemed to be "plan assets."

        As a REIT, we generally will not be subject to federal income tax on our net income distributed to our shareholders. Distributions on the Series B Preferred Shares generally will be includable in your income as dividends to the extent the distributions do not exceed our allocable current or accumulated earnings and profits, with a portion of these dividends possibly treated as capital gain dividends as explained below, but with no portion of these dividends eligible for the dividends received deduction for corporate shareholders. Distributions in excess of our allocable current or accumulated earnings and profits generally will be treated for federal income tax purposes as a return of capital to the extent of your basis in the Series B Preferred Shares, and will reduce this basis. In determining the extent to which a distribution on the Series B Preferred Shares constitutes a dividend for federal income tax purposes, our current or accumulated earnings and profits will generally be allocated first to distributions with respect to the Series B Preferred Shares along with any other class of preferred shares we have outstanding, and thereafter to distributions with respect to our common shares.

        If for any taxable year we elect to designate as "capital gain dividends," as defined in Section 857 of the Internal Revenue Code, any portion of the dividends paid for the year to holders of all classes of our shares, then the portion of dividends designated as capital gain dividends that will be allocable to the Series B Preferred Shares will be equal to the total capital gain dividends multiplied by a fraction, the numerator of which will be the total dividends paid on the Series B Preferred Shares for that taxable year, and the denominator of which shall be the total dividends paid on all classes of our stock (including the Series B Preferred Shares) for that taxable year.

        If you actually or constructively own none or a small percentage of our common shares, a redemption of your Series B Preferred Shares is likely to qualify for sale or exchange treatment because the redemption would not be "essentially equivalent to a dividend" as defined by the Internal Revenue Code. A redemption of your Series B Preferred Shares will be treated under Section 302 of the Internal Revenue Code as a distribution and hence taxable as a dividend to the extent of our current or accumulated earnings and profits, unless the redemption satisfies one of the tests set forth in Section 302(b) of the Internal Revenue Code and is therefore treated as a sale or exchange of the redeemed shares. The redemption will be treated as a sale or exchange if it (1) is "substantially disproportionate" with respect to your ownership in us, (2) results in a "complete termination" of your common and preferred share interest in us, or (3) is "not essentially equivalent to a dividend" with respect to you, all within the meaning of Section 302(b) of the Internal Revenue Code. In determining

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whether any of these tests have been met, you must generally take into account our common and preferred shares considered to be owned by you by reason of constructive ownership rules set forth in the Internal Revenue Code, as well as our common and preferred shares actually owned by you. Because the determination as to whether you will satisfy any of the tests of Section 302(b) of the Internal Revenue Code depends upon the facts and circumstances at the time that your Series B Preferred Shares are redeemed, you are advised to consult your own tax advisor to determine your particular tax treatment.

        Under Section 305 of the Internal Revenue Code, preferred stock that may be redeemed at a price higher than its issue price may have this "redemption premium" treated as a constructive distribution. Under applicable Treasury Regulations, constructive dividend treatment is required in the case of callable preferred stock only if, based on all of the facts and circumstances as of the issue date, redemption pursuant to this call right is more likely than not to occur. Even if this redemption is more likely than not to occur, constructive dividend treatment is not required if the redemption premium is solely in the nature of a penalty for premature redemption; i.e., it is a premium paid as a result of changes in economic conditions over which neither we nor you have control. The Treasury Regulations also provide a safe harbor pursuant to which an issuer's right to redeem will not be treated as more likely than not to occur. While there can be no assurance in this regard, we believe that constructive dividend treatment of the redemption premium on the Series B Preferred Shares which results from accrued but unpaid distributions, if any, should not be required.

        Fiduciaries of ERISA plans and persons making the investment decision for an IRA or any non-ERISA plan are urged to consult their advisors before making an investment in Series B Preferred Shares and to review the section of our Annual Report on Form 10-K for the year ended December 31, 2001 captioned "ERISA Plans, Keogh Plans and Individual Retirement Accounts," which is applicable to an investment in the Series B Preferred Shares. We call special attention to the fact that Series B Preferred Shares will be analyzed as a separate class under the Department of Labor regulation summarized in our Annual Report to determine whether such shares are "publicly offered securities." We believe that, immediately after this offering, Series B Preferred Shares will be owned by 100 or more investors independent of us and of each other, and therefore that the "widely held" requirement for qualification as publicly offered securities will be met. We also believe that the other requirements for such qualification will be met, so that the Series B Preferred Shares will be publicly offered securities under the Department of Labor regulations, but no assurance can be given as to these matters.

        We advise you to consult your own advisor regarding the specific federal, state, local, foreign and other tax and ERISA consequences to you, including any possible prohibited transaction concerns, of the acquisition, ownership and disposition of the Series B Preferred Shares.

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UNDERWRITING

        Subject to the terms and conditions contained in a purchase agreement between us and the underwriters named below, we have agreed to sell to each of the underwriters and each of the underwriters has severally agreed to purchase from us, the number of Series B Preferred Shares listed opposite its name.

        The underwriters have agreed to purchase all of the Series B Preferred Shares sold under the purchase agreement if any of the Series B Preferred Shares are purchased. If an underwriter defaults, the purchase agreement provides that the purchase commitments of the nondefaulting underwriters may be increased or the purchase agreement may be terminated.

        We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribute to payments the underwriters may be required to make in respect of those liabilities.

        The underwriters are offering the Series B Preferred Shares, subject to prior sale, when, as and if issued to and accepted by them, subject to approval of legal matters by their counsel, including the validity of the Series B Preferred Shares, and other conditions contained in the purchase agreement, such as the receipt by the underwriters of officers' certificates and legal opinions. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

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Commissions and Discounts

        The underwriters have advised us that they propose initially to offer the Series B Preferred Shares to the public at the initial public offering price on the cover page of this prospectus supplement and to dealers at that price less a concession not in excess of $.50 per share. The underwriters may allow, and the dealers may reallow, a discount not in excess of $.30 per share to other dealers. After the initial public offering, the public offering price, concession and discount may be changed.

        The following table shows the public offering price, underwriting discount and proceeds before expenses to us. The information assumes either no exercise or full exercise by the underwriters of their over allotment option.

        The expenses of the offering, not including the underwriting discount, are estimated at $550,000 and are payable by us.

Over Allotment Option

        We have granted an option to the underwriters to purchase up to 1,650,000 additional Series B Preferred Shares at the public offering price less the underwriting discount. The underwriters may exercise this option for 30 days from the date of this prospectus supplement solely to cover any over allotments. If the underwriters exercise this option, each will be obligated, subject to conditions contained in the purchase agreement, to purchase a number of additional Series B Preferred Shares proportionate to that underwriter's amount reflected in the above table.

New York Stock Exchange Listing

        We have filed an application to list the Series B Preferred Shares on the NYSE. If the application is approved, trading of the Series B Preferred Shares on the NYSE is expected to commence within 30 days after the initial delivery of the Series B Preferred Shares. The underwriters have advised us that they intend to make a market in the Series B Preferred Shares prior to the commencement of trading on the NYSE. The underwriters will have no obligation to make a market in the Series B Preferred Shares, however, and if they begin to make a market they may cease to do so at any time.

Price Stabilization and Short Positions

        Until the distribution of the Series B Preferred Shares is completed, rules of the SEC may limit the ability of the underwriters to bid for and purchase Series B Preferred Shares. However, the underwriters may engage in transactions that stabilize the price of the Series B Preferred Shares, such as bids or purchases to peg, fix or maintain that price.

        If the underwriters create a short position in the Series B Preferred Shares in connection with this offering (i.e., if they sell more Series B Preferred Shares than are set forth on the cover page of this prospectus supplement), the underwriters may reduce that short position by purchasing shares in the open market. The underwriters may also elect to reduce any short position through the exercise of all or part of the over allotment option described above. Purchases of Series B Preferred Shares to stabilize its price or to reduce a short position may cause the price of the Series B Preferred Shares to be higher than it might be in the absence of such purchases.

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        Neither we nor any of the underwriters makes any representation or prediction as to the direction or magnitude of any effect that the transactions described above might have on the price of the Series B Preferred Shares. In addition, neither we nor any of the underwriters makes any representation that the underwriters will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

Other Relationships

        In the ordinary course of their business, the underwriters and their affiliates have engaged in, and may in the future engage in, commercial banking and investment banking transactions with us. They have received and will receive customary fees and commissions on these transactions.

LEGAL MATTERS

        Sullivan & Worcester LLP, Boston, Massachusetts, our lawyers, will issue an opinion about the legality of the Series B Preferred Shares. Sidley Austin Brown & Wood LLP, New York, New York, the underwriters' lawyers, will also issue an opinion to the underwriters. Sullivan & Worcester LLP and Sidley Austin Brown & Wood LLP will rely, as to certain matters of Maryland law, upon an opinion of Ballard Spahr Andrews & Ingersoll, LLP, Baltimore, Maryland. Sidley Austin Brown & Wood LLP will rely, as to certain matters of Massachusetts law, upon the opinion of Sullivan & Worcester LLP. Barry M. Portnoy, one of our Managing Trustees, was a partner in the firm of Sullivan & Worcester LLP until March 31, 1997. Mr. Portnoy is also a Managing Trustee of Hospitality Properties Trust and Senior Housing Properties Trust and a director and 50% owner of Reit Management & Research LLC. Jennifer Clark, our Senior Vice President, was a partner in the firm of Sullivan & Worcester LLP until July 1999. Sullivan & Worcester LLP represents Hospitality Properties Trust, Senior Housing Properties Trust, Reit Management & Research LLC and certain of their affiliates on various matters.

EXPERTS

        The consolidated financial statements and financial statement schedules of HRPT Properties Trust appearing in our Annual Report on Form 10-K for the year ended December 31, 2001, have been audited by Ernst & Young LLP, independent auditors, as set forth in their report thereon included therein and incorporated herein by reference which is based in part on the report of Arthur Andersen LLP, independent public accountants. The consolidated financial statements and financial statement schedules referred to above are incorporated herein by reference in reliance upon such reports given on the authority of such firms as experts in accounting and auditing.

        Arthur Andersen LLP was convicted of obstruction of justice in June 2002 and ceased to practice before the SEC on August 31, 2002. Arthur Andersen LLP has experienced substantial personnel departures and may cease operations. As such, you will likely be unable to make recovery from Arthur Andersen LLP under the Securities Act of 1933, as amended, if the financial statements audited by Arthur Andersen LLP are found to contain untrue statements or omit material facts.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

        The SEC allows us to "incorporate by reference" the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus supplement, and information that we subsequently file with the SEC will automatically update and supersede this information. We incorporate by reference our documents listed below which were filed with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"):

•

Annual Report on Form 10-K for the year ended December 31, 2001;

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•

Quarterly Reports on Form 10-Q for the quarters ended March 31, 2002, and June 30, 2002;



•

Current Reports on Form 8-K dated April 4, 2002, September 4, 2002, and September 6, 2002; and



•

The description of our Series A preferred shares which is contained in a Registration Statement on Form 8-A (File No. 1-09317) filed February 20, 2001.

        We also incorporate by reference each of the following documents that we file with the SEC after the date of this prospectus supplement but before the end of the Series B Preferred Shares offering:

•

Reports filed under Sections 13(a) and (c) of the Exchange Act;



•

Definitive proxy or information statements filed under Section 14 of the Exchange Act in connection with any subsequent shareholders' meeting; and



•

Any reports filed under Section 15(d) of the Exchange Act.

        You may request a copy of any of the filings (excluding exhibits), at no cost, by telephoning us at (617) 332-3990 or writing to us at Investor Relations, HRPT Properties Trust, 400 Centre Street, Newton, Massachusetts 02458.

WHERE YOU CAN FIND MORE INFORMATION

        You may read and copy any material that we file with the SEC at the SEC's Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. You may also access our SEC filings over the Internet at the SEC's website at http://www.sec.gov.

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FORWARD-LOOKING STATEMENTS

        THIS PROSPECTUS SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS, INCLUDING THE DOCUMENTS THAT ARE INCORPORATED BY REFERENCE, CONTAIN FORWARD- LOOKING STATEMENTS AS DEFINED IN THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995 AND THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. THESE FORWARD-LOOKING STATEMENTS INCLUDE REFERENCES TO THE SECURITY OF OUR RENTAL INCOME AND OUR LEASES, OUR OCCUPANCY, POSSIBLE PROPERTY ACQUISITIONS, REPAYMENT OR REDEMPTION OF DEBT OR OTHER USES OF PROCEEDS FROM THIS OFFERING, OUR ABILITY TO PAY DISTRIBUTIONS, THE TAX TREATMENT OF OUR DISTRIBUTIONS AND OUR QUALIFICATION AS A REIT. THESE FORWARD-LOOKING STATEMENTS ARE BASED UPON OUR BELIEFS AND EXPECTATIONS, BUT THEY ARE NOT GUARANTEED AND MAY NOT OCCUR. FOR EXAMPLE, WE MAY OR MAY NOT REPAY DEBT OR PURCHASE PROPERTIES, OR WE MAY BE UNABLE TO MAINTAIN OUR TENANT OCCUPANCIES, RENTS OR TAX STATUS. THE FACT THAT WE HAVE FILED AN APPLICATION WITH THE SEC TO SELL ANY SHARES TO A FUND DOES NOT MEAN THAT SUCH SALES WILL OCCUR; THE SEC MAY NOT APPROVE THIS APPLICATION OR WE MAY DECIDE NOT TO PROCEED BECAUSE OF MARKET CONDITIONS OR FOR OTHER REASONS. INVESTORS ARE CAUTIONED NOT TO PLACE UNDUE RELIANCE UPON FORWARD-LOOKING STATEMENTS.

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        THE AMENDED AND RESTATED DECLARATION OF TRUST ESTABLISHING HRP, DATED JULY 1, 1994, A COPY OF WHICH, TOGETHER WITH ALL AMENDMENTS THERETO, IS DULY FILED IN THE OFFICE OF THE DEPARTMENT OF ASSESSMENTS AND TAXATION OF THE STATE OF MARYLAND, PROVIDES THAT THE NAME "HRPT PROPERTIES TRUST" REFERS TO THE TRUSTEES UNDER THE DECLARATION OF TRUST, AS SO AMENDED, COLLECTIVELY AS TRUSTEES, BUT NOT INDIVIDUALLY OR PERSONALLY, AND THAT NO TRUSTEE, OFFICER, SHAREHOLDER, EMPLOYEE OR AGENT OF HRP SHALL BE HELD TO ANY PERSONAL LIABILITY, JOINTLY OR SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST, HRP. ALL PERSONS DEALING WITH HRP, IN ANY WAY, SHALL LOOK ONLY TO THE ASSETS OF HRP FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY OBLIGATION.

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PROSPECTUS

$3,000,000,000

HRPT Properties Trust
Debt Securities, Preferred Shares of Beneficial Interest, Depositary
Shares, Common Shares of Beneficial Interest and Warrants

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        HRPT Properties Trust, formerly known as Health and Retirement Properties Trust (the "Company" or "HRP"), may from time to time offer in one or more series (i) its unsecured debt securities (the "Debt Securities"), (ii) its preferred shares of beneficial interest, par value $.01 per share (the "Preferred Shares"), (iii) fractional shares of the Preferred Shares (the "Depositary Shares"), (iv) its common shares of beneficial interest, par value $.01 per share (the "Common Shares"), or (v) warrants to purchase any of the above securities (the "Warrants"), with an aggregate public offering price of up to $3,000,000,000 on terms to be determined at the time of offering. The Debt Securities, Preferred Shares, Depositary Shares, Common Shares and Warrants (collectively, the "Offered Securities") may be offered, separately or together, in separate series, in amounts, at prices and on terms to be set forth in a supplement to this Prospectus (a "Prospectus Supplement").

        The specific terms of the Offered Securities in respect of which this Prospectus is being delivered will be set forth in the applicable Prospectus Supplement and will include, where applicable: (i) in the case of Debt Securities, the specific title, aggregate principal amount, currency, form (which may be registered or bearer, or certificated or global), authorized denominations, maturity, rate (or manner of calculation thereof) and time of payment of interest, terms for redemption at the option of the Company or repayment at the option of the holder, terms for sinking fund payments, terms for conversion into Preferred Shares, Depositary Shares or Common Shares, terms for subordination to other indebtedness of the Company, any original issue discount and any initial public offering price; (ii) in the case of Preferred Shares, the specific title and stated value, any dividend, liquidation, redemption, conversion, voting and other rights, and any initial public offering price; (iii) in the case of Depositary Shares, the fractional shares of Preferred Shares represented by each Depositary Share, (iv) in the case of Common Shares, any offering price; and (v) in the case of Warrants, the securities to which they relate, duration, offering price, exercise price and detachability.

        The applicable Prospectus Supplement will also contain information, where applicable, about certain United States federal income tax considerations relating to, and any listing on a securities exchange of, the Offered Securities covered by such Prospectus Supplement.

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THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

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        The Offered Securities may be offered directly, through agents designated from time to time by the Company or to or through underwriters or dealers. If any agents or underwriters are involved in the sale of any of the Offered Securities, their names, and any applicable purchase price, fee, commission or discount arrangement between or among them, will be set forth, or will be calculable from the information set forth, in an accompanying Prospectus Supplement. See "Plan of Distribution." No Offered Securities may be sold without delivery of a Prospectus Supplement describing the method and terms of the offering of such Offered Securities.

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The date of this Prospectus is June 15, 1998.

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        No person has been authorized to give any information or to make any representations other than those contained or incorporated by reference in this Prospectus in connection with the offer contained in this Prospectus and, if given or made, such information or representations must not be relied upon as having been authorized by the Company or any underwriters, agents or dealers. This Prospectus does not constitute an offer to sell or solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation. Neither the delivery of this Prospectus nor any sale made hereunder shall, under any circumstances, create an implication that there has been no change in the affairs of the Company and its subsidiaries since the date hereof or the information contained or incorporated by reference herein is correct at any time subsequent to the date hereof.

AVAILABLE INFORMATION

        The Company has filed with the Securities and Exchange Commission (the "Commission") in Washington, D.C., a registration statement on Form S-3 (together with all exhibits, schedules and amendments thereto, the "Registration Statement") under the Securities Act of 1933, as amended (the "Securities Act"), with respect to the Offered Securities. This Prospectus, which is a part of the Registration Statement, does not contain all of the information set forth in the Registration Statement. Statements in this Prospectus as to the contents of any contract or other document are not necessarily complete, and in each instance reference is made to the copy of such contract or other documents filed as an exhibit to the Registration Statement, each such statement being qualified in all respects by such reference and the exhibits and schedules thereto. For further information concerning the Company and the Offered Securities, reference is made to the Registration Statement. Copies of the Registration Statement may be obtained from the Commission at its principal office in Washington, D.C. upon payment of the prescribed fee.

        The Company is subject to the informational requirements of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, in accordance therewith, files reports and other information with the Commission. The Registration Statement, the exhibits and schedules forming a part thereof and the reports, proxy statements and other information filed by the Company with the Commission can be inspected and copies obtained at the public reference facilities maintained by the Commission at Judiciary Plaza, Room 1024, 450 Fifth Street, N.W., Washington, D.C. 20549, and at the following regional offices of the Commission: Chicago Regional Office, Suite 1400, 500 West Madison Street, Chicago, Illinois 60661-2511; and New York Regional Office, Seven World Trade Center, New York, New York 10048. Copies of such material can be obtained at prescribed rates from the Public Reference Section of the Commission at its principal office at 450 Fifth Street, N.W., Washington, D.C. 20549. The Commission maintains a World Wide Web site that contains reports, proxy and information statements and other information regarding registrants, including the Company, that file electronically with the Commission. The address of the site is http://www.sec.gov. The Company's Common Shares are traded on the New York Stock Exchange ("NYSE") under the symbol "HRP," and similar information concerning the Company may be inspected at the office of the NYSE at 20 Broad Street, New York, New York 10005.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

        The following documents, which have been filed with the Commission pursuant to the Exchange Act, are hereby incorporated in this Prospectus and specifically made a part hereof by reference: (i) the Company's Current Reports on Form 8-K dated February 11, 1998, February 12, 1998, February 17, 1998, February 18, 1998, February 19, 1998, February 27, 1998, March 19, 1998, March 24, 1998, March 30, 1998, April 10, 1998, April 14, 1998, May 11, 1998, May 22, 1998 and May 27, 1998, (ii) the Company's Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 1998 and (iii) the Company's Annual Report on Form 10-K for the year ended December 31, 1997. All documents filed by the Company pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of this Prospectus and prior to the termination of the offering of the Offered Securities shall be deemed to be incorporated by reference into this Prospectus and to be a part hereof from the respective dates of filing of such documents.

        Any statement contained herein or in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded for purposes of this Prospectus to the extent that a statement contained herein (or in the applicable Prospectus Supplement), or in any subsequently filed document that also is or is deemed to be incorporated herein by reference, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Prospectus.

(ii)

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        The Company hereby undertakes to provide without charge to each person to whom this Prospectus is delivered, upon the written or oral request of such person, a copy of any and all of the information that has been incorporated by reference in this Prospectus (excluding exhibits unless such exhibits are specifically incorporated by reference into the information that this Prospectus incorporates). Requests for such copies should be made to the Company at its principal executive offices, 400 Centre Street, Newton, Massachusetts 02158, Attention: Investor Relations, telephone (617) 332-3990.

(iii)

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THE COMPANY

        The Company is a real estate investment trust ("REIT") which invests in healthcare related real estate and office buildings. As of June 2, 1998, the Company directly owned 207 properties representing an aggregate investment of $2.5 billion (at cost), had mortgage investments in 29 properties aggregating $85.2 million and had a 9.3% equity investment in Hospitality Properties Trust ("HPT"), a New York Stock Exchange-listed REIT founded by the Company which invests in hotels, of approximately $100 million (at cost), for total real estate investments of approximately $2.7 billion located in 34 states and the District of Columbia. At the Company's 1998 annual meeting of shareholders, the shareholders voted to approve a change of the Company's name to "HRPT Properties Trust." The Company expects the name change to become effective during the summer of 1998.

        The Company is organized as a Maryland real estate investment trust. The Company's principal place of business is 400 Centre Street, Newton, Massachusetts 02158 and its telephone number is (617) 332-3990.

USE OF PROCEEDS

        Unless otherwise described in the applicable Prospectus Supplement, the Company intends to use the net proceeds from the sale of the Offered Securities for general business purposes, which may include the acquisition of, or other investments in, income producing real estate, including retirement communities, assisted living centers, long-term care facilities, medical office and other office buildings and office buildings leased to various agencies of the United States Government, and the repayment of indebtedness outstanding at such time or the reduction of amounts outstanding under the Company's credit facilities. Pending utilization as set forth above, the proceeds from the sale of the Offered Securities will be invested in short term investments, including repurchase agreements. Such investments may not be investment grade.

RATIO OF EARNINGS TO FIXED CHARGES

        The following table sets forth the Company's consolidated ratios of earnings to fixed charges for the periods indicated:

				For the years ended December 31,
		For the quarter ended March 31, 1998
				1997		1996		1995		1994		1993
Ratio of earnings to fixed charges		3.2x		3.9x		4.3x		3.4x		6.7x		6.8x

        The ratios of earnings to fixed charges presented above were computed by dividing the Company's earnings by fixed charges. For this purpose, earnings have been calculated by adding fixed charges to income before income taxes, extraordinary items and gain or loss on the disposition of real property. Fixed charges consist of interest costs, whether expensed or capitalized, the interest component of rental expense, if any, amortization of debt discounts and deferred financing costs, whether expensed or capitalized. To date, the Company has not issued any Preferred Shares; therefore, the ratio of earnings to combined fixed charges and Preferred Shares distributions are the same as the ratios of earnings to fixed charges presented above.

DESCRIPTION OF DEBT SECURITIES

        The Debt Securities will be issued under one or more indentures (an "Indenture") between the Company and a trustee (an "Indenture Trustee"). Any Indenture will be subject to, and governed by, the Trust Indenture Act of 1939, as amended (the "TIA"). The statements made hereunder relating to any Indentures and the Debt Securities to be issued thereunder are summaries of certain anticipated provisions thereof and do not purport to be complete and are subject to, and are qualified in their entirety by reference to, all provisions of the Indentures and such Debt Securities.

General

        The Company has filed with its Registration Statement with respect to the Offered Securities a form of Indenture (as supplemented from time to time, the "Senior Indenture") relating to the Senior Securities (as defined) and a form of Indenture (as supplemented from time to time, the "Subordinated Indenture") relating to the Subordinated Securities (as defined). The Debt Securities will be direct, unsecured obligations of the Company

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and, if issued under the Senior Indenture, will rank equally and ratably with other unsecured and unsubordinated indebtedness of the Company (the "Senior Securities"), or, if issued under the Subordinated Indenture, will be subordinated in right of payment to the prior payment in full of Senior Indebtedness (as defined in the applicable Prospectus Supplement) ("Subordinated Securities"). See "—Subordination". The Debt Securities may be issued without limit as to aggregate principal amount, in one or more series, in each case as established from time to time in or pursuant to authority granted by a resolution of the Board of Trustees of the Company (the "Trustees") or as established in one or more indentures supplemental to any Indenture. All Debt Securities of one series need not be issued at the same time and, unless otherwise provided, a series may be reopened, without the consent of the holders of the Debt Securities of such series, for issuances of additional Debt Securities of such series.

        It is anticipated that any Indenture will provide that the Company may, but need not, designate more than one Indenture Trustee thereunder, each with respect to one or more series of Debt Securities. Any Indenture Trustee under any Indenture may resign or be removed with respect to one or more series of Debt Securities, and a successor Indenture Trustee may be appointed to act with respect to such series. In the event that two or more persons are acting as Indenture Trustee with respect to different series of Debt Securities, each such Indenture Trustee shall be a trustee of a trust under the applicable Indenture separate and apart from the trust administered by any other Indenture Trustee, and, except as otherwise indicated herein, any action described herein to be taken by the Indenture Trustee may be taken by each such Indenture Trustee with respect to, and only with respect to, the one or more series of Debt Securities for which it is Indenture Trustee under the applicable Indenture.

        Reference is made to the Prospectus Supplement relating to the series of Debt Securities being offered for the specific terms thereof, including, where applicable, the following:

(1)

the title of such Debt Securities and whether such Debt Securities are Senior Securities or Subordinated Securities;



(2)

the aggregate principal amount of such Debt Securities and any limit on such aggregate principal amount;



(3)

the percentage of the principal amount at which such Debt Securities will be issued and, if other than the principal amount thereof, the portion of the principal amount thereof payable upon declaration of acceleration of the maturity thereof, or (if applicable) the portion of the principal amount of such Debt Securities which is convertible, or the method by which any such portion shall be determined;



(4)

if convertible, the terms on which such Debt Securities are convertible, including the initial conversion price or rate and the conversion period and any applicable limitations on the ownership or transferability of the securities into which such Debt Securities are convertible;



(5)

the date or dates, or the method for determining such date or dates, on which the principal of such Debt Securities will be payable;



(6)

the rate or rates (which may be fixed or variable), or the method by which such rate or rates shall be determined, at which such Debt Securities will bear interest, if any;



(7)

the date or dates, or the method for determining such date or dates, from which any interest will accrue, the dates on which any such interest will be payable, the record dates for such interest payment dates, or the method by which any such date shall be determined, the person to whom such interest shall be payable, and the basis upon which interest shall be calculated if other than that of a 360-day year of 12 months consisting of 30 days each;



(8)

the place or places where the principal of, any premium and interest on, and any additional amounts payable in respect of such Debt Securities will be payable, such Debt Securities may be surrendered for conversion or registration of transfer or exchange and notices or demands to or upon the Company in respect of such Debt Securities and the applicable Indenture may be served;



(9)

the period or periods within which, the price or prices at which and the terms and conditions upon which such Debt Securities may be redeemed, as a whole or in part, at the option of the Company, if the Company is to have such an option;

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(10)

the obligation, if any, of the Company to redeem, repay or purchase such Debt Securities pursuant to any sinking fund or analogous provision or at the option of a holder thereof, and the period or periods within which, the price or prices at which and the terms and conditions upon which such Debt Securities will be redeemed, repaid or purchased, as a whole or in part, pursuant to such obligation;



(11)

if other than U.S. dollars, the currency or currencies in which such Debt Securities are denominated and payable, which may be a foreign currency or units of two or more foreign currencies or a composite currency or currencies, and the terms and conditions relating thereto;



(12)

if the principal of or premium, if any, or interest on such Debt Securities is to be payable, at the election of the Company or a holder thereof, in one or more currencies or currency units other than that or those in which such Debt Securities are stated to be payable, the currency, currencies or currency units in which payment of the principal of and premium, if any, and interest on Debt Securities of such series as to which such election is made shall be payable, and the periods within which and the terms and conditions upon which such election is to be made;



(13)

whether the amount of payments of principal of (and premium, if any) or interest, if any, on such Debt Securities may be determined with reference to an index, formula or other method (which index, formula or method may, but need not, be based on a currency, currencies, currency unit or units or composite currency or currencies) and the manner in which such amounts shall be determined;



(14)

the events of default or covenants of such Debt Securities, to the extent different from or in addition to those described herein, and any provisions granting special rights to the holders of such Debt Securities upon the occurrence of events specified in such Prospectus Supplement;



(15)

whether such Debt Securities will be issued in certificated and/or book-entry form;



(16)

whether such Debt Securities will be in registered or bearer form and, if in registered form, the denominations thereof if other than $1,000 and any integral multiple thereof and, if in bearer form, the denominations thereof and terms and conditions relating thereto;



(17)

whether any of such Debt Securities are to be issuable in permanent global form (a "Global Security") and, if so, the terms and conditions, if any, upon which interests in such Debt Securities in global form may be exchanged, in whole or in part, for the individual Debt Securities represented thereby;



(18)

the applicability, if any, of the defeasance and covenant defeasance provisions described herein or any modification thereof;



(19)

if such Debt Securities are to be issued upon the exercise of debt warrants, the time, manner and place for such Debt Securities to be authenticated and delivered;



(20)

whether and under what circumstances the Company will pay additional amounts on such Debt Securities in respect of any tax, assessment or governmental charge and, if so, whether the Company will have the option to redeem such Debt Securities in lieu of making such payment; and



(21)

any other terms of such Debt Securities.

        The Debt Securities may provide for less than the entire principal amount thereof to be payable upon declaration of acceleration of the maturity thereof ("Original Issue Discount Securities"). If material or applicable, special U.S. federal income tax, accounting and other considerations applicable to Original Issue Discount Securities will be described in the applicable Prospectus Supplement.

        Except as described under "—Merger, Consolidation or Sale" or as may be set forth in any Prospectus Supplement, an Indenture will not contain any other provisions that would limit the ability of the Company to incur indebtedness or that would afford holders of the Debt Securities protection in the event of a highly leveraged or similar transaction involving the Company. However, restrictions on ownership and transfers of the Company's capital stock, designed to preserve its status as a REIT, may act to prevent or hinder a change of control. See "Redemption; Business Combinations and Control Share Acquisitions." Reference is made to the applicable Prospectus Supplement for information with respect to any deletions from, modifications of or additions to the

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events of default or covenants that are described below, including any addition of a covenant or other provisions providing event risk or similar protection.

Denominations, Interest, Registration and Transfer

        Unless otherwise described in the applicable Prospectus Supplement, the Debt Securities of any series which are registered securities, other than registered securities issued in global form (which may be of any denomination), shall be issuable in denominations of $1,000 and any integral multiple thereof.

        Unless otherwise specified in the applicable Prospectus Supplement, the principal of (and premium, if any) and interest on any series of Debt Securities will be payable at the corporate trust office of the Indenture Trustee, initially at the address which will be set forth in the applicable Prospectus Supplement; provided that, at the option of the Company, payment of interest may be made by check mailed to the address of the person entitled thereto as it appears in the applicable register or by wire transfer of funds to such person at an account maintained within the United States.

        Any interest not punctually paid or duly provided for on any interest payment date with respect to a Debt Security ("Defaulted Interest") will forthwith cease to be payable to the holder on the applicable regular record date and may either be paid to the person in whose name such Debt Security is registered at the close of business on a special record date (the "Special Record Date") for the payment of such Defaulted Interest to be fixed by the applicable Indenture Trustee, notice whereof shall be given to the holder of such Debt Security not less than 10 days prior to such Special Record Date, or may be paid at any time in any other lawful manner, all as more completely described in the applicable Indenture.

        Subject to certain limitations imposed upon Debt Securities issued in book-entry form, the Debt Securities of any series will be exchangeable for other Debt Securities of the same series and of a like aggregate principal amount and tenor of different authorized denominations upon surrender of such Debt Securities at the corporate trust office of the applicable Indenture Trustee. In addition, subject to certain limitations imposed upon Debt Securities issued in book-entry form, the Debt Securities of any series may be surrendered for conversion or registration of transfer thereof at the corporate trust office of the applicable Indenture Trustee. Every Debt Security surrendered for conversion, registration of transfer or exchange shall be duly endorsed or accompanied by a written instrument of transfer. No service charge will be made for any registration of transfer or exchange of any Debt Securities, but the Indenture Trustee or the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. If the applicable Prospectus Supplement refers to any transfer agent (in addition to the Indenture Trustee) initially designated by the Company with respect to any series of Debt Securities, the Company may at any time rescind the designation of any such transfer agent or approve a change in the location through which any such transfer agent acts, except that the Company will be required to maintain a transfer agent in each place of payment for such series. The Company may at any time designate additional transfer agents with respect to any series of Debt Securities.

        Neither the Company nor any Indenture Trustee shall be required to (i) issue, register the transfer of or exchange Debt Securities of any series during a period beginning at the opening of business 15 days before any selection of Debt Securities of that series to be redeemed and ending at the close of business on (a) if such Debt Securities are issuable only as registered securities, the day of the mailing of the relevant notice of redemption and (b) if such Debt Securities are issuable as bearer securities, the day of the first publication of the relevant notice of redemption or, if such Debt Securities are also issuable as registered securities and there is no publication, the mailing of the relevant notice of redemption, or (ii) to register the transfer of or exchange any registered security so selected for redemption in whole or in part, except, in the case of any registered security to be redeemed in part, the portion thereof not to be redeemed, or (iii) to exchange any bearer security so selected for redemption except that such a bearer security may be exchanged for a registered security of that series and like tenor; provided that such registered security shall be simultaneously surrendered for redemption, or (iv) to issue, register the transfer of or exchange any Debt Security which has been surrendered for repayment at the option of the holder, except the portion, if any, of such Debt Security not to be so repaid.

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Merger, Consolidation or Sale

        The Company may consolidate with, or sell, lease or convey all or substantially all of its assets to, or merge with or into, any other entity; provided that (i) either the Company shall be the continuing entity or the successor entity (if other than the Company) formed by or resulting from any such consolidation or merger or which shall have received the transfer of such assets shall expressly assume payment of the principal of (and premium, if any) and interest on all of the Debt Securities and the due and punctual performance and observance of all of the covenants and conditions contained in any Indenture; (ii) immediately after giving effect to such transaction and treating any indebtedness which becomes an obligation of the Company or any subsidiary as a result thereof as having been incurred by the Company or such subsidiary at the time of such transaction, no event of default under any Indenture, and no event which, after notice or the lapse of time, or both, would become such an event of default, shall have occurred and be continuing; and (iii) an officer's certificate and legal opinion covering such conditions shall be delivered to the Indenture Trustee.

Certain Covenants

        Existence.    Except as permitted under "—Merger, Consolidation or Sale," the Company will be required to do or cause to be done all things necessary to preserve and keep in full force and effect its corporate existence, rights (charter and statutory) and franchises; provided, however, that the Company shall not be required to preserve any right or franchise if it determines that the preservation thereof is no longer desirable in the conduct of its business.

        Provision of Financial Information.    Whether or not the Company is subject to Section 13 or 15(d) of the Exchange Act, the Company will, to the extent permitted under the Exchange Act, file with the Commission the annual reports, quarterly reports and other documents which the Company would have been required to file with the Commission pursuant to such Section 13 or 15(d) (the "Financial Statements") if the Company were so subject, such documents to be filed with the Commission on or prior to the respective dates (the "Required Filing Dates") by which the Company would have been required so to file such documents if the Company were so subject. The Company will also in any event (i) within 15 days of each Required Filing Date (a) transmit by mail to all holders of Debt Securities, as their names and addresses appear in the Company's security register, without cost to such holders, copies of the annual reports and quarterly reports which the Company would have been required to file with the Commission pursuant to Section 13 or 15(d) of the Exchange Act if the Company were subject to such Sections, and (b) file with the applicable Indenture Trustee copies of the annual reports, quarterly reports and other documents which the Company would have been required to file with the Commission pursuant to Section 13 or 15(d) of the Exchange Act if the Company were subject to such Sections, and (ii) if filing such documents by the Company with the Commission is not permitted under the Exchange Act, promptly upon written request and payment of the reasonable cost of duplication and delivery, supply copies of such documents to any prospective holder of Debt Securities.

        Additional Covenants.    Any additional or different covenants of the Company with respect to any series of Debt Securities will be set forth in the applicable Prospectus Supplement.

Events of Default, Notice and Waiver

        Each Indenture will provide that the following events are "Events of Default" with respect to any series of Debt Securities issued thereunder: (a) default for 30 days in the payment of any installment on any Debt Security of such series; (b) default in the payment of the principal of (or premium, if any, on) any Debt Security of such series at its maturity; (c) default in making any sinking fund payments as required for any Debt Security of such series; (d) default in the performance of any other covenant of the Company contained in the applicable Indenture (other than a covenant added to such Indenture solely for the benefit of a series of Debt Securities issued thereunder other than such series), such default having continued for 60 days after written notice as provided in such Indenture; (e) default in the payment of an aggregate principal amount exceeding a specified dollar amount of any evidence of indebtedness of the Company or any mortgage, indenture or other instrument under which such indebtedness is issued or by which such indebtedness is secured, such default having occurred after the expiration of any applicable grace period and having resulted in the acceleration of the maturity of such indebtedness, but only if such indebtedness is not discharged or such acceleration is not rescinded or annulled; (f) certain events of bankruptcy, insolvency or reorganization, or court appointment of a receiver, liquidator or trustee of the Company

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or any Significant Subsidiary (as hereinafter defined) or any of their respective property; and (g) any other event of default provided with respect to a particular series of Debt Securities. The term "Significant Subsidiary" means each significant subsidiary (as defined in Regulation S-X promulgated under the Securities Act) of the Company.

        If an Event of Default (other than an Event of Default described in clause (f) above) under any Indenture with respect to Debt Securities of any series at the time outstanding occurs and is continuing, then in every such case the applicable Indenture Trustee or the holders of not less than a majority in principal amount of the outstanding Debt Securities of that series may declare the principal amount (or, if the Debt Securities of that series are Original Issue Discount Securities or indexed securities, such portion of the principal amount as may be specified in the terms thereof) of all of the Debt Securities of that series to be due and payable immediately by written notice thereof to the Company (and to the applicable Indenture Trustee if given by the holders). If an Event of Default described in clause (f) above with respect to the Debt Securities of any series at the time outstanding shall occur, the principal amount of all the Debt Securities of that series (or, in the case of any such Original Issue Discount Security or other Debt Security, such specified amount) will automatically, and without any action by the Indenture Trustee or any holder of such series of Debt Securities, become immediately due and payable. However, at any time after such a declaration of acceleration with respect to Debt Securities of such series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be) has been made, but before a judgment or decree for payment of the money due has been obtained by the applicable Indenture Trustee, the holders of not less than a majority in principal amount of outstanding Debt Securities of such series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be) may rescind and annul such declaration and its consequences if (i) the Company shall have deposited with the applicable Indenture Trustee all required payments of the principal of (and premium, if any) and interest on the Debt Securities of such series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be), plus certain fees, expenses, disbursements and advances of the applicable Indenture Trustee, and (ii) all Events of Default, other than the non-payment of accelerated principal (or specified portion thereof), or premium, if any, or interest on the Debt Securities of such series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be) have been cured or waived as provided in the applicable Indenture. Each of the Indentures will also provide that the holders of not less than a majority in principal amount of the outstanding Debt Securities of any series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be) may waive any past default with respect to such series and its consequences, except a default (i) in the payment of the principal of (or premium, if any) or interest on any Debt Security of such series or (ii) in respect of a covenant or provision contained in the applicable Indenture that cannot be modified or amended without the consent of the holder of each outstanding Debt Security affected thereby.

        The Indenture Trustee will be required to give notice to the holders of Debt Securities within 90 days of a default under the applicable Indenture unless such default has been cured or waived; provided, however, that such Indenture Trustee may withhold notice to the holders of any series of Debt Securities of any default with respect to such series (except a default in the payment of the principal of (or premium, if any) or interest on any Debt Security of such series or in the payment of any sinking fund installment in respect of any Debt Security of such series) if specified responsible officers of such Indenture Trustee consider such withholding to be in the interest of such holders.

        Each Indenture will provide that no holders of Debt Securities of any series may institute any proceedings, judicial or otherwise, with respect to the Indenture or for any remedy thereunder, except in the case of failure of the Indenture Trustee, for 60 days, to act after it has received a written request to institute proceedings in respect of an event of default from the holders of not less than a majority in principal amount of the outstanding Debt Securities of such series, as well as an offer of reasonable indemnity. This provision will not prevent, however, any holder of Debt Securities from instituting suit for the enforcement of payment of the principal of (and premium, if any) and interest on such Debt Securities at the respective due dates thereof.

        Subject to provisions in the applicable Indenture relating to its duties in case of default, no Indenture Trustee will be under any obligation to exercise any of its rights or powers under such Indenture at the request or direction of any holders of any series of Debt Securities then outstanding under such Indenture, unless such holders shall have offered to the Indenture Trustee reasonable security or indemnity. The holders of not less than a majority in principal amount of the outstanding Debt Securities of any series (or of all Debt Securities then outstanding under the applicable Indenture, as the case may be) shall have the right to direct the time, method and place of

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conducting any proceeding for any remedy available to the applicable Indenture Trustee, or of exercising any trust or power conferred upon such Indenture Trustee. However, an Indenture Trustee may refuse to follow any direction which is in conflict with any law or the Indenture, which may involve such Indenture Trustee in personal liability or which may be unduly prejudicial to the holders of Debt Securities of such series not joining therein.

        The Company will be required to deliver to each Indenture Trustee annually a certificate, signed by one of several specified officers of the Company, stating whether or not such officer has knowledge of any default under the applicable Indenture and, if so, specifying each such default and the nature and status thereof.

Modification of the Indenture

        Modifications and amendments of an Indenture will be permitted to be made only with the consent of the holders of not less than a majority in principal amount of all outstanding Debt Securities or series of outstanding Debt Securities which are affected by such modification or amendment; provided, however, that no such modification or amendment may, without the consent of the holder of each such Debt Security affected thereby, (i) change the stated maturity of the principal of, or any installment of interest (or premium, if any) on any such Debt Security; (ii) reduce the principal amount of, or the rate or amount of interest on, or any premium payable on redemption of, any such Debt Security, or reduce the amount of principal of an Original Issue Discount Security that would be due and payable upon declaration of acceleration of the maturity thereof or would be provable in bankruptcy, or adversely affect any right of repayment of the holder of any such Debt Security; (iii) change the place of payment, or the coin or currency, for payment of principal of, premium, if any, or interest on any such Debt Security; (iv) impair the right to institute suit for the enforcement of any payment on or with respect to any such Debt Security; (v) reduce the above-stated percentage of outstanding Debt Securities of any series necessary to modify or amend the Indenture, to waive compliance with certain provisions thereof or certain defaults and consequences thereunder or to reduce the quorum or voting requirements set forth in such Indenture; or (vi) modify any of the foregoing provisions or any of the provisions relating to the waiver of certain past defaults or certain covenants, except to increase the required percentage to effect such action or to provide that certain other provisions may not be modified or waived without the consent of the holder of such Debt Security.

        Each Indenture will provide that the holders of not less than a majority in principal amount of a series of outstanding Debt Securities have the right to waive compliance by the Company with certain covenants relating to such series of Debt Securities in such Indenture.

        Modifications and amendments of an Indenture will be permitted to be made by the Company and the applicable Indenture Trustee thereunder without the consent of any holder of Debt Securities for any of the following purposes: (i) to evidence the succession of another person to the Company as obligor under such Indenture; (ii) to add to the covenants of the Company for the benefit of the holders of all or any series of Debt Securities or to surrender any right or power conferred upon the Company in such Indenture; (iii) to add events of default for the benefit of the holders of all or any series of Debt Securities; (iv) to add or change any provisions of the Indenture to facilitate the issuance of, or to liberalize certain terms of, Debt Securities in bearer form, or to permit or facilitate the issuance of Debt Securities in uncertificated form; provided that such action shall not adversely affect the interests of the holders of the Debt Securities in any material respect; (v) to change or eliminate any provisions of the Indenture; provided that any such change or elimination shall become effective only when there are no Debt Securities outstanding of any series created prior thereto which are entitled to the benefit of such provision; (vi) to secure the Debt Securities; (vii) to establish the form or terms of Debt Securities of any series, including the provisions and procedures, if applicable, for the conversion of such Debt Securities into Common Shares or Preferred Shares; (viii) to provide for the acceptance of appointment by a successor Indenture Trustee or facilitate the administration of the trusts under an Indenture by more than one Indenture Trustee; (ix) to cure any ambiguity, defect or inconsistency in an Indenture; provided that such action shall not adversely affect the interests of holders of Debt Securities of any series in any material respect; or (x) to supplement any of the provisions of an Indenture to the extent necessary to permit or facilitate defeasance and discharge of any series of such Debt Securities; provided that such action shall not adversely affect the interests of the holders of the Debt Securities of any series in any material respect.

        Each Indenture will provide that in determining whether the holders of the requisite principal amount of outstanding Debt Securities of a series have given any request, demand, authorization, direction, notice, consent or

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waiver thereunder or whether a quorum is present at a meeting of holders of Debt Securities, (i) the principal amount of an Original Issue Discount Security that shall be deemed to be outstanding shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon declaration of acceleration of the maturity thereof, (ii) the principal amount of a Debt Security denominated in a foreign currency that shall be deemed outstanding shall be the U.S. dollar equivalent, determined on the issue date for such Debt Security, of the principal amount (or, in the case of an Original Issue Discount Security, the U.S. dollar equivalent on the issue date of such Debt Security of the amount determined as provided in (i) above), (iii) the principal amount of an indexed security that shall be deemed outstanding shall be the principal face amount of such indexed security at original issuance, unless otherwise provided with respect to such indexed security in the applicable Indenture, and (iv) Debt Securities owned by the Company or any other obligor upon the Debt Securities or any affiliate of the Company or of such other obligor shall be disregarded.

        Each Indenture will contain provisions for convening meetings of the holders of Debt Securities of a series. A meeting may be called at any time by an Indenture Trustee, and also, upon request, by the Company or the holders of at least 25% in principal amount of the outstanding Debt Securities of such series, in any such case, upon notice given as provided in such Indenture. Except for any consent that must be given by the holder of each Debt Security affected by certain modifications and amendments of an Indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding Debt Securities of that series; provided, however, that, except as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority, in principal amount of the outstanding Debt Securities of a series may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of such specified percentage in principal amount of the outstanding Debt Securities for that series. Any resolution passed or decision taken at any meeting of holders of Debt Securities of any series duly held in accordance with the applicable Indenture will be binding on all holders of Debt Securities of that series. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, will be persons holding or representing a majority in principal amount of the outstanding Debt Securities of a series; provided, however, that if any action is to be taken at such meeting with respect to a consent or waiver which may be given by the holders of not less than a specified percentage in principal amount of the outstanding Debt Securities of a series, the persons holding or representing such specified percentage in principal amount of the outstanding Debt Securities of such series will constitute a quorum.

        Notwithstanding the foregoing provisions, each Indenture will provide that if any action is to be taken at a meeting of holders of Debt Securities of any series with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that such Indenture expressly provides may be made, given or taken by the holders of such series and one or more additional series: (i) there shall be no minimum quorum requirement for such meeting and (ii) the principal amount of the outstanding Debt Securities of such series that vote in favor of such request, demand, authorization, direction, notice, consent, waiver or other action shall be taken into account in determining whether such request, demand, authorization, direction, notice, consent, waiver or other action has been made, given or taken under such Indenture.

Discharge, Defeasance and Covenant Defeasance

        The Company may discharge certain obligations to holders of any series of Debt Securities that have not already been delivered to the applicable Indenture Trustee for cancellation and that either have become due and payable or will become due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with such Indenture Trustee, in trust, funds in such currency or currencies, currency unit or units or composite currency or currencies in which such Debt Securities are payable in an amount sufficient to pay the entire indebtedness on such Debt Securities in respect of principal (and premium, if any) and interest to the date of such deposit (if such Debt Securities have become due and payable) or to the stated maturity or redemption date, as the case may be.

        An Indenture may provide that, if certain provisions thereof are made applicable to the Debt Securities of or within a series pursuant to the Indenture, the Company may elect either (i) to defease and be discharged from any and all obligations with respect to such Debt Securities (except for the obligation to pay additional amounts, if any,

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upon the occurrence of certain events of tax, assessment or governmental charge with respect to payments on such Debt Securities and the obligations to register the transfer or exchange of such Debt Securities, to replace temporary or mutilated, destroyed, lost or stolen Debt Securities, to maintain an office or agency in respect of such Debt Securities and to hold moneys for payment in trust) ("defeasance") or (ii) to be released from its obligations with respect to such Debt Securities under certain sections of such Indenture (including the restrictions described under "—Certain Covenants") and, if provided pursuant to such Indenture, its obligations with respect to any other covenant, and any omission to comply with such obligations shall not constitute a default or an event of default with respect to such Debt Securities ("covenant defeasance"), in either case upon the irrevocable deposit by the Company with the applicable Indenture Trustee, in trust, of an amount, in such currency or currencies, currency unit or units of composite currency or currencies in which such Debt Securities are payable at stated maturity, or Government Obligations (as defined below), or both, applicable to such Debt Securities which through the scheduled payment of principal and interest, in accordance with their terms will provide money in an amount sufficient to pay the principal of (and premium, if any) and interest on such Debt Securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled dates therefor.

        Such a trust may be established only if, among other things, the Company has delivered to the applicable Indenture Trustee an opinion of counsel (as specified in the applicable Indenture) to the effect that the holders of such Debt Securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such defeasance or covenant defeasance had not occurred.

        "Government Obligations" means securities which are (i) direct obligations of the United States of America or the government which issued the foreign currency in which the Debt Securities of a particular series are payable, for the payment of which its full faith and credit is pledged or (ii) obligations of a person controlled or supervised by and acting as an agency or instrumentality of the United States of America or such government which issued the foreign currency in which the Debt Securities of a particular series are payable, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States of America or such other government, which, in either case, are not callable or redeemable at the option of the issuer thereof, and shall also include a depository receipt issued by a bank or trust company as custodian with respect to any such Government Obligation or a specific payment of interest on or principal of any such Government Obligation held by such custodian for the account of the holder of a depository receipt; provided that (except as required by law) such custodian is not authorized to make any deduction from the amount payable to the holder of such depository receipt from any amount received by the custodian in respect of the Government Obligations or the specific payment of interest on or principal of the Government Obligations evidenced by such depository receipt.

        Unless otherwise provided in the applicable Prospectus Supplement, if after the Company has deposited funds and/or Government Obligations to effect defeasance or covenant defeasance with respect to Debt Securities of any series, (i) the holder of a Debt Security of such series is entitled to, and does, elect pursuant to the applicable Indenture or the terms of such Debt Security to receive payment in a currency, currency unit or composite currency other than that in which such deposit has been made in respect of such Debt Security, or (ii) a Conversion Event (as defined below) occurs in respect of the currency, currency unit or composite currency in which such deposit has been made, the indebtedness represented by such Debt Security shall be deemed to have been, and will be, fully discharged and satisfied through the payment of the principal of (and premium, if any) and interest on such Debt Security as they become due out of the proceeds yielded by converting the amount so deposited in respect of such Debt Security into the currency, currency unit or composite currency in which such Debt Security becomes payable as a result of such election or such cessation of usage based on the applicable market exchange rate. "Conversion Event" means the cessation of use of (i) a currency, currency unit or composite currency both by the government of the country which issued such currency and for the settlement of transactions by a central bank or other public institutions of or within the international banking community, (ii) the ECU both within the European Monetary System and for the settlement of transactions by public institutions of or within the European Communities or (iii) any currency unit or composite currency other than the ECU for the purposes for which it was established. Unless otherwise provided in the applicable Prospectus Supplement, all payments of principal of (and premium, if any) and interest on any Debt Security that is payable in a foreign currency that ceases to be used by its government of issuance shall be made in U.S. dollars.

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        In the event the Company effects covenant defeasance with respect to any Debt Securities and such Debt Securities are declared due and payable because of the occurrence of any event of default other than the event of default described in clause (d) under "—Events of Default, Notice and Waiver" with respect to certain sections of the applicable Indenture (which sections would no longer be applicable to such Debt Securities) or described in clause (g) under "—Events of Default, Notice and Waiver" with respect to any other covenant as to which there has been covenant defeasance, the amount in such currency, currency unit or composite currency in which such Debt Securities are payable, and Government Obligations on deposit with the Trustee, will be sufficient to pay amounts due on such Debt Securities at the time of their stated maturity but may not be sufficient to pay amounts due on such Debt Securities at the time of the acceleration resulting from such event of default. However, the Company would remain liable to make payment of such amounts due at the time of acceleration.

        Notwithstanding the description set forth under "—Subordination" below, in the event that the Company deposits money or Government Obligations in compliance with the applicable Indenture in order to defease all or certain of its obligations with respect to any Subordinated Securities, the moneys or Government Obligations so deposited will not be subject to the subordination provisions of such Indenture and the indebtedness evidenced by such Subordinated Securities will not be subordinated in right of payment to the holders of senior indebtedness to the extent of the moneys or Government Obligations so deposited.

        The applicable Prospectus Supplement may further describe the provisions, if any, permitting such defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the Debt Securities of or within a particular series.

Conversion Rights

        The terms and conditions, if any, upon which the Debt Securities are convertible into Common or Preferred Shares will be set forth in the Prospectus Supplement relating thereto. Such terms will include whether such Debt Securities are convertible into Common or Preferred Shares, the conversion price (or manner of calculation thereof), the conversion period, provisions as to whether conversion will be at the option of the holders of the Company, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of such Debt Securities and any restrictions on conversion, including restrictions directed at maintaining the Company's REIT status.

Subordination

        The terms and conditions, if any, upon which Subordinated Securities of a series are subordinated to Debt Securities of other series or to other indebtedness of the Company will be set forth in the applicable Prospectus Supplement. Such terms will include a description of the indebtedness ranking senior to such Subordinated Securities, the restrictions on payments to the holders of such Subordinated Securities while a default with respect to such senior indebtedness is continuing, the restrictions, if any, on payments to the holders of such Subordinated Securities following an Event of Default, and provisions requiring holders of such Subordinated Securities to remit certain payments to holders of senior indebtedness.

Global Securities

        If so set forth in the applicable Prospectus Supplement, the Debt Securities of a series may be issued in whole or in part in the form of one or more Global Securities that will be deposited with, or on behalf of, a depositary identified in the applicable Prospectus Supplement relating to such series. Global Securities may be issued in either registered or bearer form and in either temporary or permanent form. The specific terms of the depositary arrangement with respect to any such series of Debt Securities will be described in the applicable Prospectus Supplement.

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DESCRIPTION OF SHARES

        The Declaration of Trust ("Declaration") authorizes the Company to issue an aggregate of 200,000,000 shares of beneficial interest ("Shares") in the Company, including (i) 150,000,000 Common Shares, par value $.01 per share, and (ii) 50,000,000 Preferred Shares, par value $.01 per share. The Declaration permits the Trustees to amend the Declaration to increase or decrease the authorized Shares of the Company without the requirement of shareholder approval.

        The Declaration authorizes the Trustees, without shareholder approval, from time to time to divide the Preferred Shares into classes or series and to set (or change, if the class or series has been previously established) the par value, if any, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends, qualifications or terms and conditions of redemption of such Preferred Shares as are not prohibited by the Declaration or applicable law. In connection with the adoption of the Company's shareholders rights plan (see "Redemption; Business Combinations and Control Share Acquisitions—Rights Plan," below), the Trustees established an authorized but unissued class of 1,500,000 Preferred Shares, par value $.01 per share (the "Junior Participating Preferred Shares"), described more fully below under "Description of Preferred Shares—Junior Participating Preferred Shares," and as of June 2, 1998 no other class or series of Preferred Shares had been established.

        As of June 2, 1998 there were 131,532,678 Shares outstanding, all of which were Common Shares. The Company also had outstanding as of such date $204.9 million aggregate principal amount convertible subordinated debentures of various series, all of which are convertible into Common Shares at an exercise price equal on such date to $18 per share. See "Description of Convertible Subordinated Debentures."

        The following descriptions do not purport to be complete and are subject to, and qualified in their entirety by reference to, the more complete descriptions thereof set forth in the Declaration. Capitalized terms not defined herein are as defined in the Declaration.

        Except as otherwise determined by the Trustees with respect to any class or series of Preferred Shares, all Shares: (i) will participate equally in dividends payable to shareholders when, as and if declared by the Trustees and ratably in net assets available for distribution to shareholders on liquidation or dissolution; (ii) will have one vote per share on all matters submitted to a vote of the shareholders, (iii) will not have cumulative voting rights in the election of Trustees; and (iv) will have no preference, conversion, exchange, sinking fund, redemption rights or preemptive or similar rights.

        Upon issuance in accordance with the Declaration, applicable law and the terms and conditions described in the related Prospectus Supplement, the Shares will be fully paid and nonassessable. The holders of Shares do not have preemptive rights with respect to the issuance of additional Shares or other securities of the Company.

        The authorized but unissued Shares will be available for issuance from time to time by the Company at the sole discretion of the Trustees for any proper trust purpose, which could include raising capital, providing compensation or benefits to employees and others, paying stock dividends or acquiring companies, businesses or properties. The issuance of such unissued Shares could have the effect of diluting the earnings per share and book value per share of currently outstanding Shares.

        For certain other information with respect to the Shares, see "Limitation of Liabilities; Shareholder Liability" and "Redemption; Business Combinations and Control Share Acquisitions" below.

        The Transfer Agent and Registrar for the Company's Shares is State Street Bank and Trust Company, c/o Boston EquiServe, P.O. Box 8200, Boston, Massachusetts 02266-8200 (telephone number (800) 426-5523).

DESCRIPTION OF PREFERRED SHARES

        The Declaration authorizes the Trustees, without shareholder approval, from time to time to divide the Preferred Shares into classes or series and to set (or change, if the class or series has been previously established) the par value, if any, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends, qualifications or terms and conditions of redemption of such Preferred Shares that are not prohibited by the Declaration or applicable law.

        The following description of the Preferred Shares sets forth certain general terms and provisions of the Preferred Shares to which any Prospectus Supplement may relate and a brief summary of certain terms of the

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Company's Junior Participating Preferred Shares. The statements below describing the Preferred Shares are in all respects subject to and qualified in their entirety by reference to the applicable provisions of the Declaration (including any applicable articles supplementary) and By-Laws.

General

        Subject to limitations prescribed by Maryland law and the Declaration, the Trustees are authorized to fix the number of shares constituting each series of Preferred Shares and the designations and powers, preferences and relative, participating, optional or other specific rights and qualifications, limitations or restrictions thereof, including such provisions as may be desired concerning voting, redemption, dividends, dissolution or the distribution of assets, conversion or exchange, and such other subjects or matters as may be fixed by resolutions of the Trustees.

        Reference is made to the Prospectus Supplement relating to the Preferred Shares offered thereby for specific terms, including:

(1)

the title of such Preferred Shares;

(2)

the number of shares of such Preferred Shares offered, the par value, the liquidation preference per share and the offering price of such Preferred Shares;

(3)

the dividend rate(s), period(s) and/or payment date(s) or method(s) of calculation thereof applicable to such Preferred Shares;

(4)

the date from which dividends on such Preferred Shares shall accumulate, if applicable;

(5)

the procedures for any auction and remarketing, if any, for such Preferred Shares;

(6)

the provision for a sinking fund, if any, for such Preferred Shares;

(7)

the provision for redemption, if applicable, of such Preferred Shares;

(8)

any listing of such Preferred shares on any securities exchange;

(9)

the terms and conditions, if applicable, upon which such Preferred Shares will be convertible into Common Shares of the Company or another series of Offered Securities, including the conversion price (or manner of calculation thereof);

(10)

whether interests in such Preferred Shares will be represented by Depositary Shares as more fully described below under "Description of Depositary Shares";

(11)

any other specific terms, preferences, rights, limitations or restrictions of such Preferred Shares;

(12)

a discussion of federal income tax considerations applicable to such Preferred Shares;

(13)

the relative ranking and preferences of such Preferred Shares as to dividend rights and rights upon liquidation, dissolution or winding up of the affairs of the Company;

(14)

any limitations on issuance of any series of Preferred Shares ranking senior to or on a parity with such series of Preferred Shares as to dividend rights and rights upon liquidation, dissolution or winding up of the affairs of the Company; and

(15)

any limitations on direct or beneficial ownership and restrictions on transfer.

        As described under "Description of Depositary Shares," the Company may, at its option, elect to offer Depositary Shares evidenced by depositary receipts ("Depositary Receipts"), each representing a fractional interest (to be specified in the Prospectus Supplement relating to the particular series of the Preferred Shares) in a share of the particular series of the Preferred Shares issued and deposited with a Depositary (as defined below).

Rank

        Unless otherwise determined by the Trustees and specified in the applicable Prospectus Supplement, it is expected that the Preferred Shares will, with respect to dividend rights and rights upon liquidation, dissolution or winding up of the Company, rank (i) senior to all Common Shares, and to all equity securities ranking junior to such Preferred Shares; (ii) on a parity with all equity securities issued by the Company the terms of which specifically provide that such equity securities rank on a parity with the Preferred Shares; and (iii) junior to all

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equity securities issued by the Company the terms of which specifically provide that such equity securities rank senior to the Preferred Shares.

Dividends

        Holders of Preferred Shares of each series shall be entitled to receive, when, as and if declared by the Trustees, out of assets of the Company legally available for payment, cash dividends at such rates and on such dates as will be set forth in the applicable Prospectus Supplement. Each such dividend shall be payable to holders of record as they appear on the stock transfer books of the Company (or, if applicable, on the records of the Depositary referred to below under "Description of Depositary Shares") on such record dates as shall be fixed by the Trustees.

        Dividends on any series of the Preferred Shares may be cumulative or noncumulative, as provided in the applicable Prospectus Supplement. Dividends, if cumulative, will be cumulative from and after the date set forth in the applicable Prospectus Supplement. If the Trustees fail to declare a dividend payable on a dividend payment date on any series of the Preferred Shares for which dividends are noncumulative, then the holders of such series of the Preferred Shares will have no right to receive a dividend in respect of the dividend period ending on such dividend payment date, and the Company will have no obligation to pay the dividend accrued for such period, whether or not dividends on such series are declared payable on any future dividend payment date.

        If Preferred Shares of any series are outstanding, no full dividends shall be declared or paid or set apart for payment on the Preferred Shares of the Company of any other series ranking, as to dividends, on a parity with or junior to the Preferred Shares of such series for any period unless (i) if such series of Preferred Shares has a cumulative dividend, full cumulative dividends have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for such payment on the Preferred Shares of such series for all past dividend periods and the then current dividend period or (ii) if such series of Preferred Shares does not have a cumulative dividend, full dividends for the then current dividend period have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for such payment on the Preferred Shares of such series. When dividends are not paid in full (or a sum sufficient for such full payment is not so set apart) upon the Preferred Shares of any series and the shares of any other series of Preferred Shares ranking on a parity as to dividends with the Preferred Shares of such series, all dividends declared upon Preferred Shares of such series and any other series of Preferred Shares shall in all cases bear to each other the same ratio that accrued dividends per share on the Preferred Shares of such series (which shall not include any accumulation in respect of unpaid dividends for prior dividend periods if such Preferred Shares do not have a cumulative dividend) and such other series of Preferred Shares bear to each other. No interest, or sum of money in lieu of interest, shall be payable in respect of any dividend payment or payments on Preferred Shares of such series which may be in arrears.

        Except as provided in the immediately preceding paragraph, unless (i) if such series of Preferred Shares has a cumulative dividend, full cumulative dividends on the Preferred Shares of such series have been or contemporaneously are declared and paid or declared and a sum sufficient for the repayment thereof set apart for payment for all past dividend periods and the then current dividend period, and (ii) if such series of Preferred Shares does not have a cumulative dividend, full dividends on the Preferred Shares of such series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for the then current dividend period, no dividends (other than in Common Shares or other capital stock ranking junior to the Preferred Shares of such series as to dividends and upon liquidation) shall be declared or paid or set aside for payment or other distribution shall be declared or made upon the Common Shares or any other capital stock of the Company ranking junior to or on a parity with the Preferred Shares of such series as to dividends or upon liquidation, nor shall any Common Shares or any other capital stock of the Company ranking junior to or on a parity with the Preferred Shares of such series as to dividends or upon liquidation be redeemed, purchased or otherwise acquired for any consideration (or any moneys be paid to or made available for a sinking fund for the redemption of any shares of any such stock) by the Company (except by conversion into or exchange for other capital stock of the Company ranking junior to the Preferred Shares of such series as to dividends and upon liquidation and except pursuant to certain pro rata offers to purchase or a concurrent redemption of all, or a pro rata portion of, the outstanding shares of the Preferred Shares of such series and any other series of Preferred Shares ranking on a parity with such series as to dividends and liquidation).

        Any dividend payment made on shares of a series of Preferred Shares shall first be credited against the earliest accrued but unpaid dividend due with respect to shares of such series which remains payable.

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Redemption

        If so provided in the applicable Prospectus Supplement, the Preferred Shares will be subject to mandatory redemption or redemption at the option of the Company, as a whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such Prospectus Supplement.

        The Prospectus Supplement relating to a series of Preferred Shares that is subject to mandatory redemption will specify the number of such Preferred Shares that shall be redeemed by the Company in each year commencing after a date to be specified, at a redemption price per share to be specified, together with an amount equal to all accrued and unpaid dividends thereon (which shall not, if such Preferred Shares do not have a cumulative dividend, include any accumulation in respect of unpaid dividends for prior dividend periods) to the date of redemption. The redemption price may be payable in cash or other property, as specified in the applicable Prospectus Supplement. If the redemption price for Preferred Shares of any series is payable only from the net proceeds of the issuance of capital stock of the Company, the terms of such Preferred Shares may provide that, if no such capital stock shall have been issued or to the extent the net proceeds from any issuance are insufficient to pay in full the aggregate redemption price then due, such Preferred Shares shall automatically and mandatorily be converted into shares of the applicable capital stock of the Company pursuant to conversion provisions specified in the applicable Prospectus Supplement.

        Notwithstanding the foregoing, unless (i) if such series of Preferred Shares has a cumulative dividend, full cumulative dividends on all shares of any series of Preferred Shares shall have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for all past dividend periods and the then current dividend period, and (ii) if such series of Preferred Shares does not have a cumulative dividend, full dividends on the Preferred Shares of any series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for the then current dividend period, no shares of any series of Preferred Shares shall be redeemed unless all outstanding Preferred Shares of such series are simultaneously redeemed; provided, however, that the foregoing shall not prevent the purchase or acquisition of Preferred Shares of such series pursuant to a purchase or exchange offer made on the same terms to holders of all outstanding Preferred Shares of such series, and, unless (i) if such series of Preferred Shares has a cumulative dividend, full cumulative dividends on all outstanding shares of any series of Preferred Shares have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for all past dividend periods and the then current dividend period, and (ii) if such series of Preferred Shares does not have a cumulative dividend, full dividends on the Preferred Shares of any series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for the then current dividend period, the Company shall not purchase or otherwise acquire directly or indirectly any Preferred Shares of such series (except by conversion into or exchange for capital stock of the Company ranking junior to the Preferred Shares of such series as to dividends and upon liquidation).

        If fewer than all of the outstanding Preferred Shares of any series are to be redeemed, the number of Preferred Shares to be redeemed will be determined by the Company and such shares may be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held by such holders (with adjustments to avoid redemption of fractional shares) or by lot in manner determined by the Company.

        Notice of redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each holder of record of Preferred Shares of any series to be redeemed at the address shown on the stock transfer books of the Company. Each notice shall state: (i) the redemption date; (ii) the number of shares and series of the Preferred Shares to be redeemed; (iii) the redemption price; (iv) the place or places where certificates for such Preferred Shares are to be surrendered for payment of the redemption price; (v) that dividends on the shares to be redeemed will cease to accrue on such redemption date; and (vi) the date upon which the holder's conversion rights, if any, as to such shares shall terminate. If fewer than all the Preferred Shares of any series are to be redeemed, the notice mailed to each such holder thereof shall also specify the number of Preferred Shares to be redeemed from each such holder. If notice of redemption of any Preferred Shares has been given and if the funds necessary for such redemption have been set aside by the Company in trust for the benefit of the holders of any of the Preferred Shares so called for redemption, then from and after the redemption date dividends will cease to accrue on such Preferred Shares, and any and all rights of the holders of such shares will terminate, except the right to receive the redemption price.

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Liquidation Preference

        Upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, then, before any distribution or payment shall be made to the holders of any Common Shares or any other class or series of capital stock of the Company ranking junior to the Preferred Shares in the distribution of assets upon any liquidation, dissolution or winding up of the Company, the holders of each series of Preferred Shares shall be entitled to receive out of assets of the Company legally available for distribution to shareholders liquidating distributions in the amount of the liquidation preference per share (set forth in the applicable Prospectus Supplement), plus an amount equal to all dividends accrued and unpaid thereon (which shall not include any accumulation in respect of unpaid dividends for prior dividend periods if such Preferred Shares do not have a cumulative dividend). After payment of the full amount of the liquidating distributions to which they are entitled, the holders of Preferred Shares will have no right or claim to any of the remaining assets of the Company. In the event that upon any such voluntary or involuntary liquidation, dissolution or winding up, the available assets of the Company are insufficient to pay the amount of the liquidating distributions on all outstanding Preferred Shares and the corresponding amounts payable on all shares of other classes or series of capital stock of the Company ranking on a parity with the Preferred Shares in the distribution of assets, then the holders of the Preferred Shares and all other such classes or series of capital stock shall share ratably in any such distribution of assets in proportion to the full liquidating distributions to which they would otherwise be respectively entitled.

        If liquidating distributions shall have been made in full to all holders of Preferred Shares, the remaining assets of the Company shall be distributed among the holders of any other classes or series of capital stock ranking junior to the Preferred Shares upon liquidation, dissolution or winding up, according to their respective rights and preferences and in each case according to their respective number of shares. For such purposes, the consolidation or merger of the Company with or into any other trust or corporation, or the sale, lease or conveyance of all or substantially all of the property or business of the Company, shall not be deemed to constitute a liquidation, dissolution or winding up of the Company.

Voting Rights

        Holders of the Preferred Shares will not have any voting rights, except as set forth below or as otherwise from time to time required by law or as indicated in the applicable Prospectus Supplement.

        Unless otherwise specified in the related Prospectus Supplement, at any time dividends on any Preferred Shares shall be in arrears for six consecutive quarterly periods, the holders of such Preferred Shares (voting separately as a class with all other series of preferred shares upon which like voting rights have been conferred and are exercisable) will be entitled to vote for the election of two additional trustees of the Company at the next annual meeting of shareholders and at each subsequent meeting until (i) if such series of Preferred Shares has a cumulative dividend, all dividends accumulated on such Preferred Shares for the past dividend periods and the then current dividend period shall have been fully paid or declared and a sum sufficient for the payment thereof set aside for payment or (ii) if such series of Preferred Shares does not have a cumulative dividend, four consecutive quarterly dividends shall have been fully paid or declared and a sum sufficient for the payment thereof set aside for payment. In such case, the entire Trustees of the Company will be increased by two trustees.

        Unless provided otherwise for any series of Preferred Shares, so long as any Preferred Shares remain outstanding, the Company shall not, without the affirmative vote or consent of the holders of a majority of the shares of each series of Preferred Shares outstanding at the time, given in person or by proxy, either in writing or at a meeting (such series voting separately as a class), (i) authorize or create, or increase the authorized or issued amount of, any class or series of capital stock ranking prior to such series of Preferred Shares with respect to payment of dividends or the distribution of assets upon liquidation, dissolution or winding up, or reclassify any authorized capital stock of the Company into any such shares, or create, authorize or issue any obligation or security convertible into or evidencing the right to purchase any such shares; or (ii) amend, alter or repeal the provisions of the Declaration or the certificate of designations for such series of Preferred Shares, whether by merger, consolidation or otherwise, so as to materially and adversely affect any right, preference, privilege or voting power of such series of Preferred Shares or the holders thereof; provided, however, that any increase in the amount of the authorized Preferred Shares or the creation or issuance of any other series of Preferred Shares, or any increase in the amount of authorized shares of such series or any other series of Preferred Shares, in each case ranking on a parity with or junior to the Preferred Shares of such series with respect to payment of dividends or the

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distribution of assets upon liquidation, dissolution or winding up, shall not be deemed to materially and adversely affect such rights, preferences, privileges or voting powers.

        The foregoing voting provisions will not apply if, at or prior to the time when the act with respect to which such vote would otherwise be required shall be effected, all outstanding shares of such series of Preferred Shares shall have been redeemed or called for redemption and sufficient funds shall have been deposited in trust to effect such redemption.

        As more fully described under "Description of Depositary Shares" below, if the Company elects to issue Depositary Shares, each representing a fraction of a share of a series of the Preferred Shares, each such Depositary will, in effect be entitled to such fraction of a vote per Depositary Share.

Conversion Rights

        The terms and conditions, if any, upon which shares of any series of Preferred Shares may be converted into or exchanged for Common Shares or another series of Preferred Shares or other series of Offered Securities will be set forth in the Prospectus Supplement relating thereto. Such terms will include the number of Common Shares or other securities into which the Preferred Share is convertible or exchangeable, conversion or exchange price (or manner of calculation thereof), the conversion or exchange period, provisions as to whether conversion or exchange will be at the option of the holders of the Preferred Shares or the Company, the events requiring an adjustment of the conversion or exchange price and provisions affecting conversion or exchange in the event of the redemption such Preferred Shares.

Junior Participating Preferred Shares

        In connection with the adoption of the Company's shareholders rights plan, the Trustees established an authorized but unissued class of 1,500,000 Preferred Shares. See "Redemption; Business Combinations and Control Share Acquisitions" below. Certain powers, preferences and rights and certain qualifications, limitations and restrictions of the Junior Participating Preferred Shares, when and if issued, are as follows. The statements below with respect to the Junior Participating Preferred Shares are in all respects subject to and qualified in their entirety by reference to the applicable provisions of the Declaration (including the applicable articles supplementary) and By-Laws.

        The holder of each Junior Participating Preferred Share is entitled to quarterly dividends in the greater amount of $5.00 or 100 times the quarterly per share dividend, whether cash or otherwise, declared upon the Common Shares. Dividends on the Junior Participating Preferred Shares are cumulative. Whenever dividends on the Junior Participating Preferred Shares are in arrears, the Company, among other things, is prohibited from declaring or paying dividends, making other distributions on, or redeeming or repurchasing Common Shares or other Shares ranking junior to the Junior Participating Preferred Shares, and upon failure of the Company to pay such dividends for six quarters, the holders of the Junior Participating Preferred Shares will be entitled to elect two Trustees. The holder of each Junior Participating Preferred Share is entitled to 100 votes on all matters submitted to a vote of the shareholders, voting (unless otherwise provided in the Declaration or by law) together with holders of Common Shares as one class. Upon liquidation, dissolution or winding up of the Company, the holders of Junior Participating Preferred Shares are entitled to a liquidation preference of $100 per share plus the amount of any accrued and unpaid dividends and distributions thereon (the "Liquidation Preference"), prior to payment of any distribution in respect of the Common Shares or any other Shares ranking junior to the Junior Participating Preferred Shares. Following payment of the Liquidation Preference, the holders of Junior Participating Preferred Shares are not entitled to further distributions until the holders of Common Shares shall have received an amount per share (the "Common Share Adjustment") equal to the Liquidation Preference divided by 100 (adjusted to reflect events such as stock splits, stock dividends and recapitalizations affected the Common Shares) (the "Adjustment Number"). Following the payment of the full amount of the Liquidation Preference and the Common Share Adjustment, holders of Junior Participating Preferred Shares are entitled to participate proportionately on a per share basis with holders of Common Shares in the distribution of the remaining assets to be distributed in respect of Shares in the ratio of the Adjustment Number to one, respectively. The powers, preferences and rights of the Junior Participating Preferred Shares are subject to the superior powers, preferences and rights of any senior series or class of Preferred Shares which the Trustees shall, from time to time, authorize and issue.

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DESCRIPTION OF DEPOSITARY SHARES

General

        The description set forth below and in any applicable Prospectus Supplement of certain provisions of any Deposit Agreement (as defined below) and of the Depositary Shares and depositary receipts representing Depositary Shares ("Depositary Receipts") does not purport to be complete and is subject to and qualified in its entirety by reference to the forms of Deposit Agreement and Depositary Receipts relating to each series of the Preferred Shares which have been or will be filed with the Commission at or prior to the time of the offering of such series of the Preferred Shares.

        The Company may, at its option, elect to offer fractional interests in shares of Preferred Shares, rather than shares of Preferred Shares. In the event such option is exercised, the Company will provide for the issuance by a Depositary (as defined below) to the public of receipts for Depositary Shares, each of which will represent a fractional interest to be set forth in the Prospectus Supplement relating to a particular series of the Preferred Shares which will be filed with the Commission at or prior to the time of the offering of such series of the Preferred Shares as described below. Preferred Shares of each series represented by Depositary Shares will be deposited under a separate deposit agreement (each, a "Deposit Agreement") among the Company and the depositary named therein (a "Depositary"). The Prospectus Supplement relating to a series of Depositary Shares will set forth the name and address of the Depositary. Subject to the terms of the applicable Deposit Agreement, each owner of a Depositary Share will be entitled, in proportion to the fractional interest of a share of a particular series of Preferred Shares represented by such Depositary Share to all the rights and preferences of the Preferred Shares represented by such Depositary Shares (including dividend, voting, conversion, redemption and liquidation rights).

        The Depositary Shares will be evidenced by Depositary Receipts issued pursuant to the applicable Deposit Agreement. Upon surrender of Depositary Receipts at the office of the Depositary and upon payment of the charges provided in the Deposit Agreement and subject to the terms thereof, a holder of Depositary Shares is entitled to have the Depositary deliver to such holder the whole shares of Preferred Shares underlying the Depositary Shares evidenced by the surrendered Depositary Receipts.

Dividends and Other Distributions

        A Depositary will be required to distribute all cash dividends or other cash distributions received in respect of the applicable Preferred Shares to the record holders of Depositary Receipts evidencing the related Depositary Shares in proportion to the number of such Depositary Receipts owned by such holders, subject to certain obligations of holders to file proofs, certificates and other information and to pay certain charges and expenses to such Depositary. Fractions will be rounded down to the market whole cent.

        In the event of a distribution other than in cash, a Depositary will be required to distribute property received by it to the record holders of Depositary Receipts entitled thereto, subject to certain obligations of holders to file proofs, certificates and other information and to pay certain charges and expenses to such Depositary, unless such Depositary determines that it is not feasible to make such distribution, in which case such Depositary may, with the approval of the Company, sell such property and distribute the net proceeds from such sale to such holders.

        No distributions will be made in respect of any Depositary Share to the extent that it represents any Preferred Shares which have been converted or exchanged. The Deposit Agreement will also contain provisions relating to the manner in which any subscription or similar rights offered by the Company to holders of the Preferred Shares shall be made available to holders of Depositary Shares.

Redemption of Depositary Shares

        If a series of the Preferred Shares underlying the Depositary Shares is subject to redemption, the Depositary Shares will be redeemed from the proceeds received by the Depositary resulting from the redemption, in whole or in part, of such series of the Preferred Shares held by the Depositary. The Depositary shall mail notice of redemption not less than 30 and not more than 60 days prior to the date fixed for redemption to the record holders of the Depositary Receipts evidencing the Depositary Shares to be so redeemed at their respective addresses appearing in the Depositary's books. The redemption price per Depositary Share will be equal to the applicable fraction of the redemption price per share payable with respect to such series of the Preferred Shares. Whenever

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the Company redeems shares of Preferred Shares held by the Depositary, the Depositary will redeem as of the same redemption date the number of Depositary Shares relating to shares of Preferred Shares so redeemed. If less than all of the Depositary Shares are to be redeemed, the Depositary Shares to be redeemed will be selected by lot or pro rata as may be determined by the Depositary.

        After the date fixed for redemption, the Depositary Shares so called for redemption will no longer be deemed to be outstanding and all rights of the holders of the Depositary Shares and the related Depositary Receipts will cease, except the right to receive the moneys payable upon such redemption and any money or other property to which the holders of such Depositary Shares were entitled upon such redemption upon surrender to the Depositary of the Depositary Receipts evidencing such Depositary Shares.

Voting of the Preferred Shares

        Upon receipt of notice of any meeting at which the holders of the applicable Preferred Shares are entitled to vote, a Depositary will be required to mail the information contained in such notice of meeting to the record holders of the Depositary Receipts evidencing the Depositary Shares which represent such Preferred Shares. Each record holder of Depositary Receipts evidencing Depositary Shares on the record date (which will be the same date as the record date for the Preferred Shares) will be entitled to instruct such Depositary as to the exercise of the voting rights pertaining to the amount of Preferred Shares represented by such holder's Depositary Shares. Such Depositary will endeavor, insofar as practical, to vote the amount of Preferred Shares represented by such Depositary Shares in accordance with such instructions, and the Company will agree to take all reasonable action which may be deemed necessary by such Depositary in order to enable such Depositary to do so. Such Depositary will be required to abstain from voting the amount of Preferred Shares represented by such Depositary Shares to the extent it does not receive specific instructions from the holders of Depositary Receipts evidencing such Depositary Shares. The Depositary will not be responsible for any failure to carry out any instruction to vote, or for the manner or effect of any such vote made, as long as such action or non-action is in good faith and does not result from gross negligence or willful misconduct of such Depositary.

Liquidation Preference

        In the event of the liquidation, dissolution or winding up of the Company, whether voluntary or involuntary, the holders of each Depositary Share will be entitled to the fraction of the liquidation preference accorded each Preferred Share represented by such Depositary Share, as set forth in the applicable Prospectus Supplement.

Conversion of Preferred Shares

        The Depositary Shares, as such, will not be convertible into or exchangeable for Common Shares, Preferred Shares or any other securities or property of the Company. Nevertheless, if so specified in the applicable Prospectus Supplement relating to an offering of Depositary Shares, the Depositary Receipts may be surrendered by holders thereof to the applicable Depositary with written instructions to such Depositary to instruct the company to cause conversion or exchange of the Preferred Shares represented by the Depositary Shares evidenced by such Depositary Receipts into Common Shares, other shares of Preferred Shares of the Company or such other securities as shall be provided therein, and the Company will agree that upon receipt of such instruction and any amounts payable in respect thereof, it will cause the conversion or exchange thereof utilizing the same procedures as those provided for delivery of Preferred Shares to effect such conversion or exchange. If the Depositary Shares evidenced by a Depositary Receipt are to be converted in part only, a new Depositary Receipt or Depositary Receipts will be issued for any Depositary Shares not to be converted.

Amendment and Termination of a Deposit Agreement

        Any form of Depositary Receipt evidencing Depositary Shares and any provision of a Deposit Agreement will be permitted at any time to be amended by agreement between the Company and the applicable Depositary. However, any amendment that materially and adversely alters the rights of the holders of Depositary Shares will not be effective unless such amendment has been approved by the existing holders of at least a majority of the applicable Depositary Shares then outstanding. Every holder of an outstanding Depositary Receipt at the time any

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such amendment becomes effective shall be deemed, by continuing to hold such Depositary Receipt, to consent and agree to such amendment and to be bound by the applicable Deposit Agreement as amended thereby.

        Any Deposit Agreement may be terminated by the Company upon not less than 30 days' prior written notice to the applicable Depositary if (i) such termination is necessary to preserve the Company's status as a REIT or (ii) a majority of each series of Preferred Shares affected by such termination consents to such termination, whereupon such Depositary will be required to deliver or make available to each holder of Depositary Receipts, upon surrender of the Depositary Receipts held by such holder, such number of whole or fractional Preferred Shares as are represented by the Depositary Shares evidenced by such Depositary Receipts together with any other property held by such Depositary with receipts to such Depositary Receipts. The Company will agree in each Depositary Agreement that if such Deposit Agreement is terminated to preserve the Company's status as a REIT, then the Company will use its best efforts to list the Preferred Shares issued upon surrender of the related Depositary Shares on a national securities exchange. In addition, a Deposit Agreement will automatically terminate if (i) all outstanding Depositary Shares thereunder shall have been redeemed; (ii) there shall have been a final distribution in respect of the related Preferred Shares in connection with any liquidation, dissolution or winding up of the Company and such distribution shall have been distributed to the holders of Depositary Receipts evidencing the Depositary Shares underlying such Preferred Shares; or (iii) each of the related Preferred Shares shall have been converted or exchanged into securities not so represented by Depositary Shares.

Charges of a Depositary

        The Company will pay all transfer and other taxes and governmental charges arising solely from the existence of a Deposit Agreement. In addition, the Company will pay the fees and expenses of a Depositary in connection with the initial deposit of the Preferred Shares and any redemption of Preferred Shares. However, holders of Depositary Receipts will pay any transfer or other governmental charges and the fees and expenses of a Depositary for any duties requested by such holders to be performed which are outside of those expressly provided for in the applicable Deposit Agreement.

Resignation and Removal of Depositary

        A Depositary may resign at any time by delivering to the Company notice of its election to do so, and the Company may at any time remove a Depositary, any such resignation or removal to take effect upon the appointment of a successor Depositary. A successor Depositary will be required to be appointed within 60 days after delivery of the notice of resignation or removal and will be required to be a bank or trust company having its principal office in the United States and having a combined capital and surplus of at least $50 million.

Miscellaneous

        A Depositary will be required to forward to holders of Depositary Receipts any reports and communications from the Company which are received by such Depositary with respect to the related Preferred Shares.

        Neither Depositary nor the Company will be liable if it is prevented from or delayed in, by law or any circumstances beyond its control, performing its obligations under a Deposit Agreement. The obligations of the Company and a Depositary under a Deposit Agreement will be limited to performing their duties thereunder in good faith and without gross negligence or willful misconduct, and neither the Company nor any applicable Depositary will be obligated to prosecute or defend any legal proceeding in respect of any Depositary Receipts, Depositary Shares or Preferred Shares represented thereby unless satisfactory indemnity is furnished. The Company and any Depositary will be permitted to rely on written advice of counsel or accountants, on information provided by persons presenting Preferred Shares represented thereby for deposit, holders of Depositary Receipts or other persons believed in good faith to be competent to give such information, and on documents believed in good faith to be genuine and signed by a proper party.

        In the event a Depositary shall receive conflicting claims, requests or instructions from any holders of Depositary Receipts, on the one hand, and the Company, on the other hand, such Depositary shall be entitled to act on such claims, requests or instructions received from the Company.

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DESCRIPTION OF WARRANTS

        The Company may issue, together with any other series of Offered Securities or separately, Warrants entitling the holder to purchase from or sell to the Company, or to receive from the Company the cash value of the right to purchase or sell, Debt Securities, Preferred Shares, Depositary Shares or Common Shares. The Warrants are to be issued under Warrant Agreements (each a "Warrant Agreement") to be entered into between the Company and a warrant agent (the "Warrant Agent"), all as set forth in the applicable Prospectus Supplement relating to the particular issue of Warrants.

        In the case of each series of Warrants, the applicable Prospectus Supplement will describe the terms of the Warrants being offered thereby, including the following, if applicable: (i) the offering price; (ii) the currencies in which such Warrants are being offered; (iii) the number of Warrants offered; (iv) the securities underlying the Warrants; (v) the exercise price, the procedures for exercise of the Warrants and the circumstances, if any, that will cause the Warrants to be deemed to be automatically exercised; (vi) the date on which the right shall expire; (vii) U.S. federal income tax consequences; and (viii) other terms of the Warrants.

        Warrants may be exercised at the appropriate office of the Warrant Agent or any other office indicated in the applicable Prospectus Supplement. Prior to the exercise of Warrants entitling the holder to purchase any securities, holders of such Warrants will not have any of the rights of holders of the securities purchasable upon such exercise and will not be entitled to payments made to holders of such securities.

        The Warrant Agreements may be amended or supplemented without the consent of the holders of the Warrants issued thereunder to effect changes that are not inconsistent with the provisions of the Warrants and that do not adversely affect the interests of the holders of the Warrants.

DESCRIPTION OF CONVERTIBLE SUBORDINATED DEBENTURES

        In October 1996 the Company issued $240 million aggregate principal amount of convertible subordinated debentures (the "Convertible Subordinated Debentures"), consisting of $70 million aggregate principal amount of 7.5% Convertible Subordinated Debentures due 2003, Series A (the "Series A Debentures"), $130 million aggregate principal amount of 7.5% Convertible Subordinated Debentures due 2003, Series B (the "Series B Debentures"), and $40 million aggregate principal amount of 7.25% Convertible Subordinated Debentures due 2001 (the "7.25% Debentures"). The Series A Debentures and the 7.25% Debentures were sold in offerings registered under the Securities Act, and the Series B Debentures were sold in an offering outside of the United States pursuant to Regulation S promulgated under the Securities Act.

        The Convertible Subordinated Debentures are convertible into Common Shares, initially at a conversion price of $18 per Common Share, at any time prior to maturity or earlier redemption. Such conversion price is subject to adjustment in certain events, including the payment of dividends or distributions on the Company's Shares in Common Shares or certain other securities issued by the Company, the issuance to all holders of Common Shares of rights, options or warrants entitling them to subscribe for Common Shares (or securities convertible into Common Shares), subdivisions or combinations of the Common Shares into a greater or smaller number of shares, reclassification of Common Shares resulting in an issuance of any of the Company's Shares and certain mergers or combination or sales of substantially all assets of the Company.

        As of June 2, 1998 $35.1 million in principal amount of the Series A and Series B Debentures had been converted into an aggregate of 2.0 million Common Shares, and none of the 7.25% Debentures had been converted.

        The indebtedness evidenced by the Convertible Subordinated Debentures is subordinated and junior in right of payment, to the extent set forth in the trust indenture applicable thereto, to the prior payment in full of amounts then due in respect of all indebtedness of the Company for borrowed money and certain other indebtedness, excluding (i) indebtedness of the Company to a subsidiary or an officer, director, trustee or employee of the Company or a subsidiary, (ii) indebtedness of the Company which, pursuant to the terms of the instrument creating or evidencing such indebtedness, is expressly made pari passu with or subordinate in right of payment to the Convertible Subordinated Debentures and (iii) any liability of the Company for taxes.

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        The preceding discussion of certain terms of the Convertible Subordinated Debentures is a summary of certain provisions of the Convertible Subordinated Debentures and the related trust indenture. Such discussion does not purport to be complete and is in all respects subject to and qualified in its entirety by reference to the complete terms thereof and of such trust indenture.

LIMITATION OF LIABILITY; SHAREHOLDER LIABILITY

        Maryland law permits a REIT to provide, and the Declaration provides, 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, and that, as far as practicable, each written agreement of the Company is to contain a provision to that effect. Despite these facts, counsel has advised the Company that in some jurisdictions the possibility exists that shareholders of a non-corporate entity such as the Company may be held liable for acts or obligations of the Company. Counsel has advised the Company that the State of Texas may not give effect to the limitation of shareholder liability afforded by Maryland law, but that Texas law would likely recognize contractual limitations of liability such as those discussed above. The Company intends to conduct its business in a manner designed to minimize potential shareholder liability by, among other things, inserting appropriate provisions in written agreements of the Company; however, no assurance can be given that shareholders can avoid liability in all instances in all jurisdictions.

        The Declaration provides that, upon payment by a shareholder of any such liability, the shareholder will be entitled to indemnification by the Company. There can be no assurance that, at the time any such liability arises, there will be assets of the Company sufficient to satisfy the Company's indemnification obligation. The Trustees intend to conduct the operations of the Company, with the advice of counsel, in such a way as to minimize or avoid, as far as practicable, the ultimate liability of the shareholders of the Company. The Trustees do not intend to provide insurance covering such risks to the shareholders.

REDEMPTION; BUSINESS COMBINATIONS AND CONTROL SHARE ACQUISITIONS

Redemption and Business Combinations

        For the Company to qualify as a REIT under the Code, in any taxable year, not more than 50% in value of its outstanding Shares may be owned, directly or indirectly by five or fewer individuals during the last six months of such year, and the shares must be owned by 100 or more persons during at least 335 days of a taxable year or a proportionate part of a taxable year less than 12 months. In order to meet these and other requirements, the Trustees have the power to redeem or prohibit the transfer of a sufficient number of Shares to maintain or bring the ownership of the Shares into conformity with such requirements. In connection with the foregoing, if the Trustees shall, at any time and in good faith, be of the opinion that direct or indirect ownership of shares representing more than 8.5% in value of the total Shares outstanding (the "Excess Shares") has or may become concentrated in the hands of one beneficial owner, other than Excepted Persons, the Trustees shall have the power (i) to purchase from any shareholder of the Company such Excess Shares, and (ii) to refuse to transfer or issue Shares to any person whose acquisition of such Shares would, in the opinion of the Trustees, result in the direct or indirect beneficial ownership by any person of Shares representing more than 8.5% in value of the outstanding Shares. Any transfer of Shares, options, or other securities convertible into Shares that would create a beneficial owner (other than any of the Excepted Persons) of Shares representing more than 8.5% in value of the total Shares outstanding shall be deemed void ab initio, and the intended transferee shall be deemed never to have had an interest therein. Further the Declaration provides that transfers or purported acquisitions, directly, indirectly or by attribution, of Shares, or securities convertible into Shares, that could result in disqualification of the Company as a REIT are null and void and permits the Trustees to repurchase Shares or other securities to the extent necessary to maintain the Company's status as a REIT. The purchase price for any Shares so purchased shall be determined by the price of the Shares on the principal exchange on which they are then traded, or if no such price is available, then the purchase price shall be equal to the net asset value of such Shares as determined by the Trustees in accordance with applicable law. From and after the date fixed for purchase by the Trustees, and so long as payment of the purchase price for the Shares to be so redeemed shall have been made or duly provided for, the holder of any Excess Shares so called for purchase shall cease to be entitled to distributions, voting rights and any and all other benefits with respect to such Shares, except the right to payment of the purchase price for the Shares.

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        The Declaration also requires that Business Combinations between the Company and a beneficial holder of 10% or more of the outstanding Shares (a "Related Person") be approved by the affirmative vote of the holders of at least 75% of the Shares unless (1) the Trustees by unanimous vote or written consent shall have expressly approved in advance the acquisition of the outstanding Shares that caused the Related Person to become a Related Person or shall have approved the Business Combination prior to the Related Person involved in the Business Combination having become a Related Person; or (2) the Business Combination is solely between the Company and a 100% owned affiliate of the Company. As permitted by law, the Company has elected to be governed by such provisions rather than the provisions of Subtitle 6 of Title 3 of the Corporations and Associations Article of the Annotated Code of Maryland regarding business combinations.

        Under the Declaration the number of trustees may be fixed from time to time by two-thirds of the Trustees or by an amendment of the Declaration by the shareholders of the Company, with a minimum of three and a maximum of 12 trustees, a majority of whom must be Independent Trustees. The Declaration fixes the current number of trustees of the Company at five and divides the Trustees into three groups. Trustees in each group are elected to three-year terms. As the Trustees' terms expire, replacements are elected by a majority of the outstanding Shares. The classified nature of the Trustees may make it more difficult for the shareholders to remove the management of the Company than if all trustees were elected on an annual basis. Vacancies may be filled by a majority of the remaining trustees, except that a vacancy among the Independent Trustees must be filled by a majority of the remaining Independent Trustees or by majority vote of the Company's shareholders. Any trustee may be removed for cause by all the remaining trustees, or without cause by vote of two-thirds of the Shares then outstanding and entitled to vote thereon.

        The provisions regarding business combinations and the classified nature of the Trustees and certain other matters may not be repealed or amended without the affirmative vote of at least 75% of the shareholders of the Company, provided that the Trustees, by two-thirds vote, may, without the approval or consent of the shareholders, adopt any amendment that they in good faith determine to be necessary to permit the Company to qualify as a REIT under the Code.

        The foregoing provisions may have the effect of discouraging unilateral tender offers or other takeover proposals which certain shareholders might deem in their interests or pursuant to which they might receive a substantial premium for their Shares. The provisions could also have the effect of insulating current management against the possibility of removal and could, by possibly reducing temporary fluctuations in market price caused by accumulations of Shares, deprive shareholders of opportunities to sell at a temporarily higher market price. However, the Trustees believe that inclusion of the business combination provisions in the Declaration may help assure fair treatment of shareholders and preserve the assets of the Company.

Control Share Acquisition

        Maryland law provides for a limitation of voting rights in a "control share acquisition." The Maryland statute defines a control share acquisition at the 20%, 33¹/3% and 50% acquisition levels, and requires a two-thirds vote (excluding shares owned by the acquiring person and certain members of management) to accord voting rights to shares acquired in a control share acquisition. The statute would require the target company to hold a special meeting at the request of an actual or proposed control share acquiror subject to compliance with certain conditions by such acquiror. In addition, unless the charter, declaration of trust or by-laws provide otherwise, the statute gives the company, within certain time limitations, various redemption rights if there is a shareholder vote on the issue and the grant of voting rights is not approved, or if an "acquiring person statement" is not delivered to the target company within 10 days following a control share acquisition. Moreover, unless the charter, declaration of trust or by-laws provide otherwise, the statute provides that if, before a control share acquisition occurs, voting rights for control shares are approved at a shareholders' meeting and the acquiror becomes entitled to vote a majority of the shares entitled to vote, then all other shareholders may exercise appraisal rights. The statute does not apply to shares acquired in a merger, consolidation or share exchange if the company is a party to the transaction. An acquisition of shares may be exempted from the control share statute provided that a charter, declaration of trust or by-law provision is adopted for such purpose prior to the control share acquisition. There are no such provisions in the Declaration or By-Laws of the Company.

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Rights Plan

        In October 1994 the Trustees adopted a shareholder rights plan (the "Rights Plan"). The Rights Plans provides for the distribution of one Junior Participating Preferred Share purchase right (a "Right") for each Common Share. Each Right entitles the holder to buy 1/100^th of a Junior Participating Preferred Share (or, in certain circumstances, to receive cash, property, Common Shares or other securities of the Company) at an exercise price of $50 per 1/100^th of a Junior Participating Preferred Share. Certain powers, preferences and rights and certain qualifications, limitations and restrictions of the Junior Participating Preferred Shares are summarized above under "Description of Preferred Shares—Junior Participating Shares."

        Initially, the Rights are attached to certificates representing Common Shares. The Rights will separate from such Common Shares and a "Distribution Date" will occur upon earlier of (i) 10 business days (or such later date as the Trustees may determine before a Distribution Date occurs) following a public announcement by the Company that a person or group affiliated or associated persons, with certain exceptions (an "Acquiring Person"), has acquired, or has obtained the right to acquire, beneficial ownership of 10% or more of the outstanding Common Shares (the date of such announcement being a "Share Acquisition Date") or (ii) 10 business days (or such later date as the Trustees may determine before a Distribution Date occurs) following the commencement of a tender offer or exchange offer that would result in a person becoming an Acquiring Person.

        Until the Distribution Date, (i) the Rights will be evidenced by the certificates for Common Shares and will be transferred with and only with such Common Share certificates, (ii) Common Share certificates will contain a notation incorporating the rights agreement pursuant to which the Rights were issued (the "Rights Agreement") by reference and (iii) the surrender for transfer of any certificates for Common Shares outstanding will also constitute the transfer of the Rights associated with the Common Shares represented by such certificates.

        The Rights are not exercisable until the Distribution Date and will expire at the close of business on October 17, 2004, unless earlier redeemed or exchanged by the Company as described below. Until a Right is exercised, the holder thereof, as such, has no rights as a shareholder of the Company, including, without limitation, the right to vote or to receive dividends.

        In the event (a "Flip-In Event") a Person becomes an Acquiring Person (except pursuant to a tender or exchange offer for all outstanding Common Shares at a price and on terms which a majority of the Company's Outside Trustees (as defined in the Rights Agreement) determines to be fair to and otherwise in the best interests of the Company and its shareholders (a "fair offer")), each holder of a Right will thereafter have the right to receive, upon exercise of such Right, Common Shares (or, in certain circumstances, cash, property or other securities of the Company) having a Current Market Price (as defined in the Rights Agreement) equal to two times the exercise price of the Right. Notwithstanding the foregoing, following the occurrence of any Flip-In Event, all Rights that are, or (under certain circumstances specified in the Rights Agreement) were, beneficially owned by any Acquiring Person (or by certain related parties) will be null and void in the circumstances set forth in the Rights Agreement. However, Rights will not be exercisable following the occurrence of any Flip-In Event until such time as the Rights are no longer redeemable by the Company as set forth below.

        In the event (a "Flip-Over Event") that, at any time on or after the Share Acquisition Date, (i) the Company shall take part in a merger or other business combination transaction (other than certain mergers that follow a fair offer) and the Company shall not be the surviving entity or (ii) the Company shall take part in a merger or other business combination transaction in which the Common Shares are changed or exchanged (other than certain mergers that follow a fair offer) or (iii) 50% or more of the Company's assets or earning power is sold or transferred, each holder of a Right (except Rights which previously have been voided, as set forth above) shall thereafter have the right to receive, upon exercise, a number of shares of common stock of the acquiring company having a Current Market Price equal to two times the exercise price of the Right. Flip-In Events and Flip-Over Events are collectively referred to as "Triggering Events."

        The Purchase Price payable and the number of Junior Participating Preferred Shares (or the amount of cash, property or other securities) issuable upon exercise of the Rights are subject to adjustment from time to time to prevent dilution (i) in the event of a share dividend on, or a subdivision, combination or reclassification of, the Junior Participating Preferred Shares, (ii) if holders of the Junior Participating Preferred Shares are granted certain rights or warrants to subscribe for Junior Participating Preferred Shares or convertible securities at less than the

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Current Market Price of the Junior Participating Preferred Shares or (iii) upon the distribution to holders of the Junior Participating Preferred Shares of evidences of indebtedness or assets (excluding regular quarterly cash dividends) or of subscription rights or warrants (other than those referred to above). With certain exceptions, no adjustment in the Purchase Price will be required until cumulative adjustments amount to at least 1% of the Purchase Price. The Company is not required to issue fractional Shares upon the exercise of any Right, and in lieu thereof, a cash payment will be made.

        At any time until 10 business days following the Share Acquisition Date, the Company may redeem the Rights in whole, but not in part, at a price of $.01 per Right, payable, at the option of the Company, in cash, Common Shares or other consideration as the Trustees may determine. Immediately upon the effectiveness of the action of the Trustees ordering redemption of the Rights, the Rights will terminate and the only right of the holders of Rights will be to receive the $.01 per Right redemption price.

        The term of the Rights, other than key financial terms and the date on which the Rights expire, may be amended by the Trustees prior to the Distribution Date. Thereafter, the provisions of the Rights Agreement may be amended by the Trustees only in order to cure any ambiguity, defect or inconsistency, to make changes which do not adversely affect the interests of holders of Rights (excluding the interests of any Acquiring Person and certain other related parties) or to shorten or lengthen any time period under the Rights Agreement; provided, however, that no amendment to lengthen the time period governing redemption is permitted to be made at such time as the Rights are not redeemable.

PLAN OF DISTRIBUTION

        The Company may sell the Offered Securities to one or more underwriters for public offering and sale by them or may sell the Offered Securities to investors directly or through agents. Any such underwriter or agent involved in the offer and sale of the Offered Securities will be named in the applicable Prospectus Supplement.

        The distribution of Offered Securities may be effected from time to time in one or more transactions at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices related to such market prices or at negotiated prices. In connection with the sale of Offered Securities, underwriters or agents may receive or be deemed to have received compensation from the Company or from purchasers in the form of underwriting discounts, concessions or commissions. Underwriters may sell Offered Securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or from purchasers.

        Any underwriting compensation paid by the Company to underwriters or agents in connection with the offering of Offered Securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers, will be set forth in the applicable Prospectus Supplement. Underwriters, dealers and agents participating in the distribution of the Offered Securities may be deemed to be underwriters, and any discounts, concessions and commissions received by them and any profit realized by them on resale of the Offered Securities may be deemed to be underwriting discounts and commissions, under the Securities Act. Underwriters, dealers and agents may be entitled, under agreements entered into with the Company, to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act.

        If so indicated in the applicable Prospectus Supplement, the Company will authorize underwriters or other persons acting as the Company's agents to solicit offers by certain institutions to purchase Offered Securities from the Company at the public offering price set forth in such Prospectus Supplement pursuant to contracts providing for payment and delivery on a future date or dates. Institutions with whom such contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions, and other institutions, but will in all cases be subject to the approval of the Company. Any such contracts will be subject to the condition that the purchase by an institution of the Offered Securities covered by its contracts shall not at the time of delivery be prohibited under the law of any jurisdiction in the United States to which such institution is subject and, if a portion of the Offered Securities is being sold to underwriters, may be subject to the condition that the Company shall have sold to such underwriters the Offered Securities not sold for delayed delivery. The underwriters and such other persons will not have any responsibility in respect of the validity or performance of such contracts.

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        Unless otherwise specified in the related Prospectus Supplement, each series of Offered Securities will be a new issue with no established trading market, other than Common Shares which are listed on the New York Stock Exchange. Any Common Shares sold pursuant to a Prospectus Supplement will be listed on such Exchange. The Company may elect to list any other series of Offered Securities on an exchange, but is not obligated to do so. Any underwriters to whom Offered Securities are sold by the Company for public offering and sale may make a market in such Offered Securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. No assurance can be given as to the liquidity of or the trading markets for any Offered Securities.

        Certain of the underwriters and their affiliates may be customers of, engage in transactions with and perform services for the Company and its subsidiaries in the ordinary course of business.

        The specific terms and manner of sale of the Offered Securities will be set forth or summarized in the applicable Prospectus Supplement.

LEGAL MATTERS

        Certain legal matters with respect to the Offered Securities offered by the Company will be passed upon for the Company by Sullivan & Worcester LLP, Boston, Massachusetts. Sullivan & Worcester LLP, will rely, as to all matters of Maryland law, upon one or more opinions of Piper & Marbury L.L.P., Baltimore, Maryland. Barry M. Portnoy, was a partner in the firm of Sullivan & Worcester LLP until March 31, 1997 and is a Managing Trustee of the Company and HPT, a director and 50% shareholder of REIT Management & Research, Inc, the Company's investment advisor ("RMR") and its affiliate, HRPT Advisors, Inc., the predecessor investment advisor of the Company. Mr. Portnoy is also a director and/or significant shareholder of certain lessees of and borrowers from the Company. Sullivan & Worcester LLP represents HPT, RMR, certain of such lessees and borrowers and certain affiliates of each of the foregoing on various matters.

EXPERTS

        The consolidated financial statements and financial statement schedules of the Company included or incorporated by reference in the Company's Annual Report on Form 10-K for the year ended December 31, 1997, have been audited by Ernst & Young LLP, independent auditors, as set forth in their reports thereon included or incorporated by reference therein and incorporated herein by reference which, as to the years 1997 and 1996, are based in part on the report of Arthur Andersen LLP, independent public accountants. Such consolidated financial statements and financial statement schedules are incorporated herein by reference in reliance upon such reports given upon the authority of such firms as experts in accounting and auditing.

        The statement of revenue and certain expenses for 1600 Market Street for the year ended December 31, 1997 included in the Company's Current Report on Form 8-K dated March 30, 1998 has been audited by Ernst & Young LLP, independent auditors, as set forth in their report included therein and incorporated herein by reference. Such financial statements are incorporated herein by reference in reliance upon such report given upon the authority of such firm as experts in accounting and auditing.

        The statement of revenues and certain expenses of 1735 Market Street for the year ended December 31, 1997 incorporated by reference in this Prospectus and elsewhere in the registration statement has been audited by Arthur Andersen LLP, independent public accountants, and is included herein in reliance upon the authority of said firm as experts in giving said reports.

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THE AMENDED AND RESTATED DECLARATION OF TRUST OF THE COMPANY, DATED JULY 1, 1994, A COPY OF WHICH, TOGETHER WITH ALL AMENDMENTS THERETO (THE "DECLARATION"), IS DULY FILED IN THE OFFICE OF THE DEPARTMENT OF ASSESSMENTS AND TAXATION OF THE STATE OF MARYLAND, PROVIDES THAT THE NAME "HEALTH AND RETIREMENT PROPERTIES TRUST" REFERS TO THE TRUSTEES UNDER THE DECLARATION COLLECTIVELY AS TRUSTEES, BUT 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.

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11,000,000 Shares

HRPT Properties Trust

8³/4% Series B Cumulative Redeemable Preferred Shares
(Liquidation Preference $25 Per Share)

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PROSPECTUS SUPPLEMENT

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Merrill Lynch & Co.

UBS Warburg

A.G. Edwards & Sons, Inc.

Legg Mason Wood Walker

Incorporated 

Morgan Stanley

Prudential Securities

Raymond James

RBC Capital Markets

Wachovia Securities

September 6, 2002

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QuickLinks

TABLE OF CONTENTS Prospectus Supplement
PROSPECTUS SUPPLEMENT SUMMARY
The Company
HRP Capitalization
HRP Tenants
HRP Lease Expirations
Principal Place of Business
The Offering
USE OF PROCEEDS
CAPITALIZATION
RECENT DEVELOPMENTS
THE COMPANY
States In Which HRP Properties Are Located
Market Areas From Which HRP Receives More Than 5% Of Its Total Rents
HRP Tenants
HRP Lease Expirations
HRP Tenants Responsible For More Than 1% of Rents
RATIO OF EARNINGS TO FIXED CHARGES
DESCRIPTION OF THE SERIES B PREFERRED SHARES
FEDERAL INCOME TAX AND ERISA CONSIDERATIONS
UNDERWRITING
LEGAL MATTERS
EXPERTS
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
WHERE YOU CAN FIND MORE INFORMATION
FORWARD-LOOKING STATEMENTS
AVAILABLE INFORMATION
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
THE COMPANY
USE OF PROCEEDS
RATIO OF EARNINGS TO FIXED CHARGES
DESCRIPTION OF DEBT SECURITIES
DESCRIPTION OF SHARES
DESCRIPTION OF PREFERRED SHARES
DESCRIPTION OF DEPOSITARY SHARES
DESCRIPTION OF WARRANTS
DESCRIPTION OF CONVERTIBLE SUBORDINATED DEBENTURES
LIMITATION OF LIABILITY; SHAREHOLDER LIABILITY
REDEMPTION; BUSINESS COMBINATIONS AND CONTROL SHARE ACQUISITIONS
PLAN OF DISTRIBUTION
LEGAL MATTERS
EXPERTS