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TABLE OF CONTENTS
INDEX TO FINANCIAL STATEMENTS

Table of Contents

As filed with the Securities and Exchange Commission on December 31, 2009

Registration No. 333-            

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-11

FOR REGISTRATION UNDER THE SECURITIES ACT OF 1933
OF SECURITIES OF CERTAIN REAL ESTATE COMPANIES

Government Properties Income Trust
(Exact name of registrant as specified in governing instruments)

400 Centre Street
Newton, Massachusetts 02458
(617) 219-1440
(Address, including zip code, and telephone number,
including area code, of registrant's principal executive offices)

David M. Blackman
Treasurer and Chief Financial Officer
Government Properties Income Trust
400 Centre Street
Newton, Massachusetts 02458
(617) 219-1440
(Name, address, including zip code, and telephone number, including area code, of agent for service)

COPIES TO:

William J. Curry Sullivan & Worcester LLP One Post Office Square Boston, Massachusetts 02109 (617) 338-2800		Bartholomew A. Sheehan Sidley Austin LLP 787 Seventh Avenue New York, New York 10019 (212) 839-5300

        Approximate date of commencement of proposed sale to the public:    As soon as practicable after the Registration Statement becomes effective.

          If any of the Securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, check the following box. o

          If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering o

          If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

          If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

          If delivery of the prospectus is expected to be made pursuant to Rule 434, check the following box. o

          Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer" "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer o		Accelerated filer o		Non-accelerated filer ý (Do not check if a smaller reporting company)		Smaller reporting company o

CALCULATION OF REGISTRATION FEE

Title of securities to be registered		Proposed maximum aggregate offering price(1)		Amount of registration fee(2)
Common Shares of Beneficial Interest, $0.01 par value per share		$174,242,250		12,423.47

(1)

Estimated solely for the purposes of calculating the registration fee pursuant to Rule 457(o) of the Securities Act of 1933, as amended.

(2)

Calculated pursuant to Rule 457(o) of the Securities Act of 1933, as amended.

          The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and we are not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PROSPECTUS (Subject to Completion)

Issued December 31, 2009

6,500,000 Shares

Government Properties Income Trust

Common Shares of Beneficial Interest

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We are a Maryland real estate investment trust that owns and intends to invest in properties that are majority leased to government tenants. We own 33 properties and have entered into a binding purchase and sale agreement to acquire an additional property. Together, our owned properties and the property that we expect to acquire are located in 16 states and the District of Columbia; these properties contain approximately 4.2 million rentable square feet, of which approximately 96.1% is leased to the U.S. Government and four state governments.

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We are offering 6,500,000 of our common shares of beneficial interest, $0.01 par value per share, or Shares. We expect to use the net proceeds of this offering to reduce amounts outstanding under our secured revolving credit facility and to fund our business activities, including some or all of the purchase price of our pending acquisition.

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Our Shares are traded on the New York Stock Exchange, or the NYSE, under the trading symbol "GOV." On December 22, 2009, the last reported sale price of our Shares by the NYSE was $23.45 per share.

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We are organized as a Maryland real estate investment trust and intend to elect and qualify to be taxed as a real estate investment trust for U.S. federal income tax purposes, or a REIT, commencing with our taxable year ending December 31, 2009. Subject to certain exceptions described herein, our Amended and Restated Declaration of Trust provides that no person may own, or be deemed to own, more than 9.8% of the number or value of shares of any class or series of our outstanding shares of beneficial interest, including our Shares.

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Investing in our Shares involves risks. See "Risk Factors" beginning on page 13.

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PRICE $              A SHARE

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		Price to Public		Underwriting Discounts and Commissions		Proceeds, Before Expenses, to Us
Per Share		$		$		$
Total		$		$		$

We have granted the underwriters the right to purchase up to an additional 975,000 Shares 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 is truthful or complete. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the Shares to purchasers on January      , 2010.

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MORGAN STANLEY

January      , 2010

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TABLE OF CONTENTS

Prospectus Summary		1
Risk Factors		13
Warning Concerning Forward Looking Statements		24
Use of Proceeds		26
Share Price Range and Distributions		27
Distribution Policy		28
Capitalization		29
Selected Financial and Pro Forma Financial Information		30
Management's Discussion and Analysis of Financial Condition and Results of Operations		33
Business		48
Management		62
Manager		66
Certain Relationships and Related Person Transactions		72
Principal Shareholders		78
Description of Our Shares		79
Material Provisions of Maryland Law and of Our Declaration of Trust and Bylaws		81
Federal Income Tax Considerations		93
ERISA Plans, Keogh Plans and Individual Retirement Accounts		112
Underwriters		114
Legal Matters		118
Experts		118
Where You Can Find Additional Information		118
Index to Financial Statements		F-1

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        You should rely only on the information contained in this prospectus. We have not, and the underwriters have not, authorized any other 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 is accurate only as of the date on the front cover of this prospectus. Our business, financial condition, results of operations and prospects may have changed since that date.

        Unless the content otherwise requires, references in this prospectus to "we," "us" or "our" mean Government Properties Income Trust and its consolidated subsidiaries, and references in this prospectus to "HRP" mean HRPT Properties Trust and its consolidated subsidiaries. References in this prospectus to our "Declaration of Trust" and our "Bylaws" refer to our Amended and Restated Declaration of Trust and our Amended and Restated Bylaws, respectively.

        References in this prospectus to a "government tenant" mean a tenant that is, or is majority controlled by (whether through equity ownership or voting control), a nation or government, a state or other political subdivision thereof, any federal, state, local or foreign entity or organization exercising executive, legislative, judicial, regulatory or administrative functions of or pertaining to government, including any governmental authority, agency, department, board, commission or instrumentality of the United States, any state of the United States or any political subdivision thereof, and any tribunal. References in this prospectus to properties that are "majority leased to government tenants" mean properties where 50% or more of the rentable square feet of such property is then leased to one or more government tenants.

STATEMENT CONCERNING LIMITED LIABILITY

        THE AMENDED AND RESTATED DECLARATION OF TRUST ESTABLISHING GOVERNMENT PROPERTIES INCOME TRUST, DATED JUNE 8, 2009, AS FILED WITH THE STATE DEPARTMENT OF ASSESSMENTS AND TAXATION OF MARYLAND, PROVIDES THAT NO TRUSTEE, OFFICER, SHAREHOLDER, EMPLOYEE OR AGENT OF GOVERNMENT PROPERTIES INCOME TRUST SHALL BE HELD TO ANY PERSONAL LIABILITY, JOINTLY OR SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST, GOVERNMENT PROPERTIES INCOME TRUST. ALL PERSONS DEALING WITH GOVERNMENT PROPERTIES INCOME TRUST IN ANY WAY SHALL LOOK ONLY TO THE ASSETS OF GOVERNMENT PROPERTIES INCOME TRUST FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY OBLIGATION.

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PROSPECTUS SUMMARY

        This summary does not contain all of the information that you should consider before investing in our Shares. You should read the entire prospectus carefully before making an investment decision, especially the risks discussed under "Risk Factors." Unless otherwise stated, the information in this prospectus assumes that 6,500,000 Shares are sold at a public offering price of $23.45 per Share, which was the last reported sale price of our Shares on December 22, 2009, as reported on the NYSE, and that the over-allotment option granted to the underwriters is not exercised. Unless otherwise stated, rental income is the annualized rents from our tenants (including the tenant at the property in Landover, Maryland that we expect to acquire during the first quarter of 2010) pursuant to signed leases as of September 30, 2009, plus estimated expense reimbursements, and excludes lease value amortization.

Our Company

        We are a Maryland real estate investment trust that owns and intends to invest in properties that are majority leased to government tenants. We intend to elect and qualify to be taxed as a REIT for U.S. federal income tax purposes commencing with our taxable year ending December 31, 2009. We completed our initial public offering, or IPO, on June 8, 2009. At that time, we owned 29 properties consisting of approximately 3.3 million rentable square feet of space. Since the completion of our IPO, we have acquired four properties and have entered into a binding purchase and sale agreement to acquire an additional property; these five properties are majority leased to government tenants and have an aggregate purchase price of approximately $133.0 million, including the assumption of $24.8 million of mortgage debt associated with the property that we expect to acquire during the first quarter of 2010. Our pending acquisition is subject to customary closing conditions and no assurance can be given that it will be consummated. In aggregate, these five properties include 919,495 rentable square feet and are 99.7% occupied, with a weighted average remaining lease term (based on rentable square feet) of approximately 6.6 years.

As of September 30, 2009 and pro forma for our recent and pending acquisitions, 28 of our properties are leased primarily to the U.S. Government and six of our properties are leased to the States of California, Maryland, Minnesota and South Carolina, or the State Governments. Pro forma for our recent and pending acquisitions, approximately 83.9% of our rental income as of September 30, 2009 would have been paid by the U.S. Government and 9.9% would have been paid by the State Governments, while approximately 6.2% would have been paid by non-government tenants. The following chart and table depict the geographic and tenant diversity of our properties based on annualized rental income as of September 30, 2009, pro forma for our recent and pending acquisitions:		Geographic Diversity D.C., MD and VA, or the DC metro area, comprise approximately 34.3%

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Tenant Diversity

        Federal, state and local governments are among the largest users of leased real estate in the United States. We believe that the expected increase in government regulation resulting from the recent economic recession will increase the U.S. Government's demand for leased office space. Similarly, we believe that budgetary pressures may cause an increased demand for leased space, as opposed to government owned space, among government tenants generally. Our business plan is to maintain our properties, seek to renew our leases as they expire, selectively acquire additional properties that are majority leased to government tenants and pay distributions to our shareholders.

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Recent Developments

Investment Activity

        Since the completion of our IPO on June 8, 2009, we have acquired four properties and have entered into a binding purchase and sale agreement to acquire one additional property. These properties are majority leased to government tenants and have an aggregate purchase price of approximately $133.0 million, including the assumption of $24.8 million of mortgage debt associated with the property that we expect to acquire during the first quarter of 2010. These five properties include 919,495 rentable square feet and are 99.7% occupied with a weighted average remaining lease term (based on rentable square feet) of approximately 6.6 years.

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In August 2009, we acquired an industrial property in Nashua, New Hampshire with 321,800 rentable square feet, which is 100% leased to the United States Postal Service, or USPS, for $18.2 million.



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In December 2009, we acquired an office property in Sacramento, California with 163,425 rentable square feet, which is approximately 62% leased to the State of California and occupied by the California Department of Finance, for $40.0 million.



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In December 2009, we acquired a second office property in Sacramento, California with 110,500 rentable square feet, which is 100% leased to the State of California and occupied by the California National Guard, for $15.1 million.



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In December 2009, we acquired an office property in Arlington Heights, Illinois with 57,770 rentable square feet, which is 100% leased to the U.S. Government and occupied by the Occupational Health and Safety Administration, or OSHA, for $16.0 million.



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In November 2009, we entered into a binding purchase and sale agreement to acquire an office and warehouse building located in Landover, Maryland with 266,000 rentable square feet, which is 100% leased to the U.S. Government and occupied by the Defense Intelligence Agency, with a purchase price of $43.7 million. This property is encumbered by a mortgage for $24.8 million that is currently not prepayable. We have completed our acquisition diligence for this property and expect to assume this mortgage and acquire this property during the first quarter of 2010; however, no assurance can be given that this acquisition will be consummated in that time period or at all.

        Beginning in the first quarter of 2009, we are required to expense all of the costs associated with acquiring properties. Prior to the first quarter 2009, these expenses were capitalized into the cost of acquired properties. As a result of our acquisition activity, we expect to incur approximately $818,000 in expenses in the fourth quarter of 2009. Given the timing of recent and pending acquisitions, we will record minimal revenues in the fourth quarter of 2009 for recent acquisitions we acquired in December 2009, and we will not record any revenue in the fourth quarter of 2009 for our pending acquisition.

        In December 2009, we entered into an agreement to acquire an office property in Lakewood, Colorado with 166,745 rentable square feet, which is 100% leased to the U.S. Government, with a purchase price of approximately $29.1 million. This property is encumbered by a mortgage for approximately $10.4 million that is currently not prepayable. We are currently conducting ongoing acquisition due diligence with respect to this property, and assuming successful completion of our due diligence review and satisfaction of the other closing conditions specified in the purchase and sale agreement, we expect to consummate this acquisition during the first quarter of 2010. However, no assurance can be given that this acquisition will be consummated in that time period or at all.

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        The following table provides additional information about our recent and pending acquisitions:

Investment in Affiliated Insurance Company

        In December 2009, we invested $5.1 million in Affiliated Insurance Company, or AIC, an Indiana Insurance Company, with Reit Management & Research LLC, or RMR, and other companies to which RMR provides management services. AIC was formed and licensed to provide insurance and risk management services. We currently own approximately 14.3% of this insurance company. Through this insurance business, we may benefit financially by possibly reducing insurance expenses and/or by having our pro rata share of any profits realized by this insurance business. However, AIC has not yet commenced providing insurance or risk management services to any party, including us. For more information about this investment, see "Certain Relationships and Related Person Transactions."

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Distributions

        We intend to pay regular quarterly distributions to holders of our Shares. Our current quarterly distribution rate is $0.40 per Share ($1.60 on an annualized basis). However, the timing and amount of any distributions will be at the discretion of our Board of Trustees and will depend upon various factors that our Board of Trustees deems relevant, including our results of operations, our financial condition, our capital requirements, our funds from operations, or FFO, our cash available for distribution, restrictive covenants in our financial or other contractual arrangements (including our secured revolving credit facility), economic conditions and restrictions under Maryland law. In October 2009, we declared a common share distribution of $0.50 per Share. This distribution consisted of a regular quarterly distribution of $0.40 per Share with respect to the quarter ended September 30, 2009, plus an additional $0.10 relating to the 22 days after the completion of our IPO during the prior quarter. In December 2009, we declared a regular quarterly common share distribution of $0.40 per Share with respect to the quarter ended December 31, 2009. This distribution will be paid on or about January 29, 2010 to our shareholders of record on December 21, 2009. Persons who purchase Shares in this offering will not receive this distribution. Subject to the approval of our Board of Trustees, we expect to declare our next regular quarterly distribution shortly before or after March 31, 2010. Shareholders who purchase Shares in this offering and who continue to own those Shares through the record date for any such distribution will receive that distribution. For more information, see "Distribution Policy."

Investment Highlights

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Strong Credit Quality Tenants.  Pro forma for our recent and pending acquisitions, approximately 83.9% of our rental income as of September 30, 2009 would have been paid by the U.S. Government and approximately 9.9% would have been paid by the State Governments. We currently expect that our future investments will be focused on properties that are majority leased to government tenants. We believe that government tenants generally have strong credit characteristics and are less likely to default under lease obligations than commercial tenants. Accordingly, we believe that our expected distributions may be more secure than the distributions paid by many other REITs.



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Favorable Lease Renewal Experience.  Based on the experience of our manager, RMR, we believe that properties leased to government tenants are typically relet to the same tenant or another government tenant. During the period that RMR has managed the properties that comprise our portfolio, all of the space in our government leased properties that has been relet was relet to a government tenant.



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Significant Presence in the DC Metro Area.  Pro forma for our recent and pending acquisitions, approximately 34.3% of our rental income as of September 30, 2009 would have been paid by tenants located in the DC metro area. We believe that the DC metro area has one of the most stable bases of office employment in the United States and it is less likely to experience high office vacancy rates than most other areas of the country.



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Growth Potential.  During the past 40 years, the amount of space owned by the Government Services Administration, or the GSA, which administers most of the non-military real estate requirements of the U.S. Government, has remained relatively constant, but the amount of GSA leased space has increased from approximately 46 million square feet to approximately 178 million square feet. Due to the large amount of space currently leased to government tenants and our belief that government demand for leased office space will increase, we believe that we will have significant opportunities to acquire additional properties that are majority leased to government tenants.



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Access to Capital; Conservative Capital Structure.  We have a $250 million secured revolving credit facility. Pro forma for our recent and pending acquisitions, as of September 30, 2009, the aggregate principal amount outstanding under our secured revolving credit facility would have been

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approximately $155.3 million and our ratio of debt to undepreciated book value of our properties would have been approximately 25.3%. We expect to use the net proceeds of this offering to reduce amounts outstanding under our secured revolving credit facility and to fund our business activities, including some or all of the purchase price of our pending acquisition. As adjusted for the use of net proceeds from this offering to reduce the amount outstanding under our secured revolving credit facility and assuming completion of our pending acquisition, we expect our debt will be approximately $33.6 million, or approximately 5.5% of the pro forma undepreciated book value of our properties. Our current policy is to limit our total debt to no more than 50% of the undepreciated book value of our properties.

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Exclusive Focus on Acquiring Properties Majority Leased to Government Tenants.  We are the only public real estate company with an exclusive focus on acquiring and owning properties that are majority leased to government tenants. We believe that our exclusive focus on properties that are majority leased to government tenants, combined with our access to a committed secured revolving credit facility, may provide us with a competitive advantage in acquiring additional properties.



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Experienced Management.  Because of RMR's experience in leasing to government tenants, we believe that our management by RMR is a competitive advantage which may help us to meet government tenants' special needs, retain government tenants when their leases expire and locate additional properties for investment that are majority leased to government tenants.

Our History and Management

        We were organized under Maryland law on February 17, 2009 as a wholly owned subsidiary of HRP. HRP is a NYSE listed REIT that owns office and industrial properties with a historical cost of over $6 billion. We were organized to concentrate the ownership of certain HRP properties that are majority leased to government tenants and to expand such investments. On April 24, 2009, we acquired 100% ownership of the properties that we owned at the time of our IPO by means of a contribution from HRP to one of our subsidiaries. On June 8, 2009, we issued 10,000,000 Shares in our IPO and became a separate publicly owned company. Thereafter, our underwriters exercised their over-allotment option and we sold an additional 1,500,000 Shares on June 30, 2009.

        We do not have any employees. Instead, we are managed by RMR and the services typically provided by employees and most of our other required general and administrative services are provided to us by RMR. RMR, which began operations in 1986, manages one of the largest combinations of publicly owned real estate in the United States, including at September 30, 2009 over 1,350 commercial properties located in 45 states, the District of Columbia, Puerto Rico and Ontario, Canada, with a historical cost of approximately $17 billion. RMR has approximately 580 employees in its Boston area headquarters and in regional offices throughout the United States, including an office in Washington, D.C. that is focused on leasing to government tenants. RMR began managing properties leased to government tenants in 1997. RMR has extensive experience in dealing with the GSA and government leasing requirements. RMR also manages HRP, two other NYSE listed REITs and two publicly owned real estate based operating companies. RMR is owned by Barry Portnoy and Adam Portnoy who are our Managing Trustees. Adam Portnoy is also our President. For more information, see "Manager."

Relationship with HRP

        In connection with our formation, HRP invested $5 million in us and we issued 9,950,000 of our Shares to HRP, which it continues to own. On April 24, 2009, HRP contributed the properties that we owned at the time of our IPO to one of our subsidiaries and made an additional contribution to us of approximately $1.8 million, and we borrowed $250 million under our secured revolving credit facility and distributed these funds to HRP. In connection with our IPO, HRP advanced approximately $6 million to us to pay certain expenses associated with our IPO, which was repaid in full following completion of our IPO

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with a borrowing under our secured revolving credit facility. HRP currently owns 46.3% of our outstanding Shares.

        HRP has a history of successfully divesting certain of its properties into new REITs that, over time, have become separately owned. In 1995, HRP created Hospitality Properties Trust, or HPT, a REIT that invests in hotels and other hospitality properties, and in 1999, HRP created Senior Housing Properties Trust, or SNH, a REIT that invests in senior living and healthcare related real estate. When HPT and SNH were created they were each wholly owned by HRP. Over time, as HPT and SNH grew their respective investments and issued new shares, and as HRP distributed or gradually sold its shares in HPT and SNH, HRP's ownership interest in each REIT declined to zero. HRP's percentage ownership of us will decrease to 35.6% as a result of this offering (34.4% if the underwriters exercise in full their over-allotment option). We, our trustees, our executive officers and HRP have agreed, subject to certain exceptions, not to sell or transfer any Shares for a period of 90 days after the date of this prospectus without first obtaining the written consent of Morgan Stanley & Co. Incorporated. HRP may dispose of its Shares after the 90 day period, but has advised us that it has no present intention to do so.

        Upon completion of our IPO, we entered into a transaction agreement with HRP, or the transaction agreement, governing our separation from and relationship with HRP. Under the transaction agreement, while HRP owns more than 10% of our outstanding Shares or we and HRP have common management, HRP will not acquire ownership of properties that are majority leased to government tenants unless a majority of our Independent Trustees have decided not to make the acquisition, and we will not acquire ownership of properties that are not majority leased to government tenants unless a majority of HRP's Independent Trustees have decided not to make the acquisition. HRP currently owns 18 properties, with approximately 2.2 million rentable square feet, that are majority leased to government tenants. Under the transaction agreement, while HRP owns more than 10% of our outstanding Shares or we and HRP have common management, we have a right of first refusal to acquire any property owned by HRP that HRP determines to divest if the property is then majority leased to government tenants. For more information, see "Certain Relationships and Related Person Transactions."

Our Management Agreements with RMR

        RMR receives management fees from us, of which there are three components:

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Business Management Base Fee.  There are two components of the business management fee. The annual amount of the business management base fee is equal to the sum of (a) 0.5% of the historical cost to HRP of any properties transferred to us by HRP and (b) 0.7% of our cost of any properties we acquire up to and including $250 million, including our recent and pending acquisitions, plus 0.5% of our cost of any additional properties in excess of $250 million.



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Property Management Fee.  The amount of the property management fee is equal to 3% of the gross rents we collect from tenants, plus 5% of any construction costs we incur for building improvements, tenant fit out and other tenant inducements.



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Incentive Fee.  Beginning with the year ending December 31, 2010, the annual amount of any incentive fee will be equal to 15% of any increase in FFO Per Share (as defined in our business management agreement) for such year over FFO Per Share in the prior year, multiplied by the weighted average number of Shares outstanding during the year to which the fee applies calculated on a fully diluted basis; provided, however, the incentive fee for any year will not exceed $0.02 per Share multiplied by such weighted average number of Shares outstanding on a fully diluted basis. For purposes of calculating any incentive fee for the year ending December 31, 2010, our 2009 FFO Per Share will be calculated based on annualized figures for the period beginning June 8, 2009, which was the day on which we completed our IPO, and ending on December 31, 2009. Any incentive fees earned by RMR will be paid in Shares.

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        The business management base fee and property management fee that we pay to RMR with respect to the properties transferred to us by HRP do not exceed the corresponding fees that HRP would have paid to RMR with respect to such properties had we remained wholly owned by HRP. Accordingly, RMR will not receive any increase in the business management base fee or the property management fee as a result of the transfer to us of any properties by HRP. Also, the incentive fee that RMR will be eligible to receive from us for the year ending December 31, 2010 will be substantially similar in structure to the incentive fee that HRP currently pays to RMR, but with a maximum amount of $0.02 per Share. As a separate publicly traded company, we may be able to increase our investments in properties that are majority leased to government tenants more quickly than HRP might be able to increase such investments, and, as we increase our investments, RMR's fees will increase. We do not pay RMR any acquisition, leasing, disposition or financing fees. On a pro forma basis, taking account of our recent and pending acquisitions, the annualized business management base fee and the annualized property management fee payable by us to RMR, in aggregate, would have been approximately $6.2 million.

        Under our management agreements with RMR, we acknowledge that RMR manages other businesses, including HRP, SNH and HPT, and will not be required to present us with opportunities to invest in properties that are primarily of a type that are within the investment focus of another business now or in the future managed by RMR. As a result, while we are managed by RMR, we will have limited ability to invest in properties other than properties that are majority leased to government tenants. Under our business management agreement, RMR has agreed not to present other businesses that it now or in the future manages with opportunities to invest in properties that are majority leased to government tenants unless our Independent Trustees have determined not to invest in the opportunity. For more information, see "Manager."

Risk Factors

        The following is a summary of certain material risks you will be exposed to by investing in our Shares:

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There are a limited number of properties that are majority leased to government tenants and competition to buy these properties may be significant. Accordingly, we may not be able to grow our business.



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The weighted average remaining term, based upon rent, of our current leases is 4.2 years. Pro forma for our recent and pending acquisitions, as of September 30, 2009 the weighted average remaining term, based upon rent, of our leases would have been 4.7 years. When our leases expire, we may be unable to relet our properties to current or new tenants at rental rates that equal or exceed current rates.



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Changes in government requirements for leased space, including changes to the U.S. Government's budget for construction, repair and alteration of federal buildings, may make it more difficult for us to retain our government tenants or to locate additional properties that are majority leased to government tenants. Some of our government tenants have the right to vacate our properties and terminate their lease obligations before their lease terms expire.



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The U.S. Government's "green lease" policies may require us to make expensive changes to our properties for them to remain competitive.



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We have a concentration of properties in the DC metro area. An economic downturn or any significant increase in speculative development of office properties in the DC metro area may cause the occupancy and rents that we can achieve in that area to decline.



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Real estate ownership is illiquid and involves risks of loss, damage and unforeseeable costs.

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HRP's ownership of 35.6% of our Shares after completion of this offering may result in your inability to influence our policies. HRP's sale of our Shares which it owns, or the possibility of such a sale, may depress the market price of our Shares.



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Provisions in the transaction agreement and our management agreements with RMR may restrict our investment activities and create conflicts of interest.



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Our payment of distributions to our shareholders is not assured. Any distributions will be determined at the discretion of our Board of Trustees.



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The trading market for our Shares may be volatile.

Tax Status

        We intend to elect and qualify to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, or the Code, commencing with our taxable year ending December 31, 2009. If we qualify for taxation as a REIT, under current federal income tax law we generally will not be taxed on income we distribute to our shareholders so long as we distribute at least 90% of our annual REIT taxable income and satisfy a number of organizational and operational requirements to which REITs are subject. Even if we qualify for taxation as a REIT, we are subject to certain state and local taxes on our income and property. For more information, see "Federal Income Tax Considerations."

Restrictions on Ownership and Transfer of Shares

        Subject to certain exceptions, our Declaration of Trust provides that no person may own, or be deemed to own by virtue of the attribution provisions of the Code, more than 9.8% of the number or value of shares of any class or series of our outstanding shares of beneficial interest, including our Shares. These restrictions are intended to assist with our REIT compliance under the Code and otherwise to promote our orderly governance. These restrictions do not apply to HRP, RMR or their affiliates. For more information, see "Material Provisions of Maryland Law and of Our Declaration of Trust and Bylaws—Restrictions on Ownership and Transfers of Shares."

Our Address

        Our principal executive offices are located at 400 Centre Street, Newton, Massachusetts 02458 and our telephone number is (617) 219-1440.

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THE OFFERING

        All of the Shares offered hereby are being sold by us.

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SUMMARY SELECTED FINANCIAL AND PRO FORMA FINANCIAL INFORMATION

        You should read the following summary selected financial and pro forma financial information in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations," the audited Combined Financial Statements of Certain Government Properties (wholly owned by HRPT Properties Trust) and notes thereto, the unaudited Condensed Consolidated Financial Statements of Government Properties Income Trust and notes thereto and the unaudited Pro Forma Financial Statements of Government Properties Income Trust and notes thereto, all included elsewhere in this prospectus. The summary historical consolidated financial information for the nine months ended September 30, 2008 and 2009 have been derived from our unaudited condensed consolidated financial statements for the period of time for which we have been a separate public company and from Certain Government Properties (wholly owned by HRPT Properties Trust) for periods prior to our becoming a separate public company, appearing elsewhere in this prospectus. The summary historical balance sheet information as of September 30, 2009 has been derived from our unaudited condensed consolidated financial statements. The summary historical consolidated financial information for the years ended December 31, 2006, 2007 and 2008 and the summary historical consolidated balance sheet information as of December 31, 2007 and 2008 have been derived from the audited combined financial statements of Certain Government Properties (wholly owned by HRPT Properties Trust), appearing elsewhere in this prospectus. The summary pro forma consolidated financial information for the year ended December 31, 2008 and the nine months ended September 30, 2009 and the summary pro forma consolidated balance sheet information as of September 30, 2009 have been derived from our unaudited pro forma financial statements, appearing elsewhere in this prospectus. The summary selected financial and pro forma financial information in this section is not intended to replace these audited and unaudited financial statements. In addition, the pro forma balance sheet and income statement data below have been adjusted for our recent acquisitions completed since September 30, 2009, our pending acquisition, this offering and the use of the estimated net proceeds from this offering as described under "Use of Proceeds," and the income statement data has also been adjusted to reflect our formation transactions, our IPO and the application of the net proceeds therefrom and our Nashua, NH acquisition in August 2009. The summary selected financial and pro forma financial information below and the financial statements included in this prospectus do not necessarily reflect what our results of operations, financial position and cash flows would have been if we had operated as a stand-alone company during all periods presented, and these historical and pro forma results should not be relied upon as an indicator of our future performance.

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RISK FACTORS

        Our business faces many risks. The risks described below are all of the material risks that we can identify at this time. You should carefully consider all of the risks described below and the other information contained in this prospectus before making a decision to buy our Shares. If any of these risks occur, our business, financial condition and results of operations could be harmed. In that case, the trading price of our Shares could decline and you might lose part or all of your investment in our Shares. Additional risks that we do not know of, or that we currently think are immaterial, may also become important factors that affect us and your investment in us.

Risks Related to Our Business

We may be unable to identify additional properties to acquire and grow our business.

        Our business plan is to acquire additional properties that are majority leased to government tenants. There are a limited number of such properties, and we will have fewer opportunities to grow our investments than REITs that purchase properties that are leased to both government and non-government tenants or that are not leased when they are acquired. Accordingly, our business plan to acquire additional properties that are majority leased to government tenants may not succeed.

We may be unable to access the capital necessary to repay debts, invest in our properties or fund acquisitions.

        We intend to elect and qualify to be taxed as a REIT for U.S. federal income tax purposes commencing with our taxable year ending December 31, 2009. To qualify for taxation as a REIT, we will be required to distribute at least 90% of our annual REIT taxable income (excluding capital gains) and satisfy a number of organizational and operational requirements to which REITs are subject. Accordingly, we generally will not be able to retain sufficient cash from operations to repay debts, invest in our properties or fund acquisitions. Our business and growth strategies depend, in part, upon our ability to raise additional capital at reasonable costs to repay our debts, invest in our properties and fund new acquisitions. We expect to use the net proceeds of this offering to reduce amounts outstanding under our secured revolving credit facility and to fund our business activities, including some or all of the purchase price of our pending acquisition. Recently, there has been a significant reduction in the amount of capital available on a global basis. Our ability to raise reasonably priced capital is not guaranteed; we may be unable to raise reasonably priced capital because of reasons related to our business or for reasons beyond our control, such as market conditions. Additionally, since we are a recently formed company with a limited operating history, it may be more difficult for us to raise reasonably priced capital than more established companies, many of which have established financing programs and, in some cases, have investment grade credit ratings. If we are unable to raise reasonably priced capital, our business and growth strategies may fail.

We face significant competition.

        We plan to acquire properties that are majority leased to government tenants whenever we are able to identify attractive opportunities and have sufficient available financing to complete such acquisitions. We face competition for acquisition opportunities from other investors and this competition may subject us to the following risks:

•

we may be unable to acquire a desired property because of competition from other well capitalized real estate investors, including publicly traded and private REITs, private investment funds and others; and



•

competition from other real estate investors, which may increase if access to credit becomes more readily available and lending terms become more lenient, may significantly increase the purchase price we must pay to acquire properties.

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In addition, substantially all of our properties face competition for tenants. Some competing properties may be newer, better located and more attractive to tenants. Competing properties may have lower rates of occupancy than our properties, which may result in competing owners leasing available space at lower rents than we offer at our properties. This competition may affect our ability to attract and retain tenants and may reduce the rents we are able to charge. Government tenants may be particularly difficult to attract and retain because they may be viewed as desirable tenants by other landlords.

Our acquisitions may not be successful.

        Our business strategy contemplates acquisitions of additional properties that are majority leased to government tenants. We cannot assure you that acquisitions we make will prove to be successful. Notwithstanding pre-acquisition due diligence, we do not believe that it is possible to fully understand a property before it is owned and operated for an extended period of time. For example, we could acquire a property that contains undisclosed defects in design or construction. In addition, after our acquisition of a property, the market in which the acquired property is located may experience unexpected changes that adversely affect the property's value. The occupancy of properties that we acquire may decline during our ownership, and rents that are in effect at the time a property is acquired may decline thereafter. For these reasons, among others, our property acquisitions may cause us to experience losses.

We may be unable to lease our properties when our leases expire.

        The weighted average remaining term of our leases is 4.2 years, or 4.7 years pro forma for our recent and pending acquisitions, based upon annual rental income under leases in effect as of September 30, 2009 (4.2 years and 4.8 years, respectively, based upon occupied square footage). Leases representing approximately 67.2% of our rental income as of September 30, 2009 (65.5% of our occupied square footage), or 59.2% of our rental income (57.4% of our occupied square footage) pro forma for our recent and pending acquisitions, will expire by December 31, 2013. Although we will seek to renew our leases with current tenants when these leases expire, we can provide no assurance that we will be successful in doing so. If our tenants do not renew their leases, we may be unable to enter leases with substitute tenants.

When we renew leases or lease to new tenants our rents may decline and our expenses may increase.

        When we renew leases or lease to new tenants we may receive less rent than we received under the leases that expired. Laws and regulations applicable to government leasing often require public solicitations of bids when new or renewal leases are being considered. Market conditions may require us to lower our rents to retain government tenants. Also, whenever we renew leases or lease to new tenants we may have to spend substantial amounts for tenant fit out, leasing commissions and other tenant inducements. As a consequence of lower rents or increased expenses when we renew leases or lease to new tenants, our net income and cash available to pay distributions to you may decline.

Some government tenants have the right to terminate their leases prior to their lease expiration date.

        Almost all of our current rents come from government tenants. Some of our leases with government tenants allow the tenants to vacate the leased premises before the stated terms of the leases expire with little or no liability. In particular:

•

Tenants occupying approximately 14.8% of our rentable square feet and contributing approximately 12.2% of our rental income as of September 30, 2009, or 12.7% of our rentable square feet and 10.3% of our rental income, pro forma for our recent and pending acquisitions, respectively, have currently exercisable rights to terminate their leases before the stated term of their lease expires.



•

In 2010, 2011 and 2012, early termination rights become exercisable by other tenants who currently occupy an additional approximately 7.1%, 2.7% and 1.2% of our rentable square feet, respectively, and contribute an additional approximately 6.1%, 4.6% and 1.3% of our rental income as of

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September 30, 2009, respectively, or 6.1%, 2.3% and 1.0% of our rentable square feet and approximately 5.2%, 3.9% and 1.1% of our rental income, respectively, pro forma for our recent and pending acquisitions.

•

In addition, a tenant at a building we recently acquired has the right to terminate its lease in 2014. On a pro forma basis, this tenant occupies approximately 2.3% of our rentable square feet and contributes approximately 2.8% of our rental income as of September 30, 2009.



•

Two of our state government tenants have the currently exercisable right to terminate their leases if these states do not appropriate rent in their respective annual budgets. These two tenants occupy approximately 3.7% of our rentable square feet and contribute approximately 2.7% of our rental income as of September 30, 2009, or 3.1% of our rentable square feet and contribute approximately 2.3% or our rental income, pro forma for our recent and pending acquisitions.

        For fiscal policy reasons, security concerns or other reasons, some or all of our government tenants may decide to vacate our properties. If a significant number of such vacancies occur, our rental income may materially decline and we may become unable to pay regular distributions to you or we may reduce the amounts of such distributions.

An increase in the amount of government owned real estate may adversely affect us.

        The American Recovery and Reinvestment Act of 2009, enacted in February 2009, included several billion dollars for construction, repair and alteration of government owned buildings. It remains unclear as to what extent expenditure of these funds may impact us. If there is a large increase in the amount of government owned real estate as a consequence of this legislation, certain government tenants may relocate from our properties to government owned real estate. Similarly, it may become more difficult for us to renew our government leases when they expire or to locate additional properties that are majority leased to government tenants in order to grow our business.

The U.S. Government's "green lease" policies may adversely affect us.

        In recent years the U.S. Government has instituted "green lease" policies which allow a government tenant to require leadership in energy and environmental design for commercial interiors, or LEED®-CI, certification in selecting new premises or renewing leases at existing premises. In addition, the Energy Independence and Security Act of 2007 allows the GSA to prefer buildings for lease that have received an "Energy Star" label. Obtaining such certifications and labels may be costly and time consuming, but our failure to do so may result in our competitive disadvantage in acquiring new or retaining existing government tenants.

We currently have a concentration of properties in the DC metro area and are exposed to changes in market conditions in this area.

        Approximately 34.3% of our rental income as of September 30, 2009 was received from properties located in the DC metro area. Pro forma for our recent and pending acquisitions, approximately 34.3% of our rental income as of September 30, 2009 would have been received from properties located in the DC metro area. A downturn in economic conditions in this area could result in reduced demand from tenants for our properties or lower the rents that our government tenants in this area are willing to pay when our leases expire and renewal terms are negotiated. Additionally, within the past few years there has been a large number of speculative real estate developments in the DC metro area, and a surplus of newly developed space could adversely affect our ability to retain our government tenants when our leases expire.

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Our failure or inability to meet certain terms of our secured revolving credit facility would adversely affect our business and may prevent our paying distributions to you.

        Our $250 million secured revolving credit facility includes various conditions to our borrowing and various financial and other covenants and events of default. We may not be able to satisfy all of these conditions or may default on some of these covenants for various reasons, including matters which are beyond our control. For example, our ability to borrow under our secured revolving credit facility depends upon the appraised value of the collateral properties which secure our secured revolving credit facility and the net rental income received from the collateral properties. Similarly, important financial covenants in our secured revolving credit facility include our covenant to maintain certain debt service and leverage ratios, our compliance with which depends upon the net rental income we receive from all our properties and their appraised value. In the event that the occupancy at a number of our properties, including properties which are collateral for our secured revolving credit facility, were to decline, if the rents we can charge for these properties were to decline, or if the appraised value of our properties were to decline, we may be unable to borrow under our secured revolving credit facility, the amounts we may borrow under our secured revolving credit facility may decrease or we may be in default under our secured revolving credit facility. In addition, our secured revolving credit facility provides that a change in control of us or a termination of our management agreements with RMR may cause the amounts outstanding under our secured revolving credit facility to become immediately due and payable.

        If we are unable to borrow under our secured revolving credit facility we may be unable to meet our business obligations or to grow by buying additional properties, or we may be required to sell some of our properties. If we default under our secured revolving credit facility at a time when borrowed amounts are outstanding under our secured revolving credit facility, our lenders may demand immediate payment or foreclose our properties or realize upon other assets which are their collateral. The covenants and conditions which apply to us with respect to debt, if any, which we incur in addition to our secured revolving credit facility may be more restrictive than the covenants and conditions in our secured revolving credit facility. Any default under our outstanding secured revolving credit facility or other debt we may incur would likely have serious and adverse consequences to us and would likely cause the market value of our Shares to materially decline.

        A covenant in our secured revolving credit facility prohibits us from paying distributions in excess of 95% of our Funds From Operations, as defined therein, other than certain distributions in connection with qualifying as a REIT. Our rental income could decline to a level whereby our current distribution rate would exceed 95% of our Funds From Operations, and, as a consequence, we would not be permitted under our secured revolving credit facility to make a distribution at our expected distribution rate.

Amounts recoverable under our leases for increased operating costs may be less than the actual increased costs.

        Under most of our leases, the tenant's obligation to pay us adjusted rent for increased operating costs (e.g. the costs of cleaning services, supplies, materials, maintenance, trash removal, landscaping, water, sewer charges, heating, electricity and certain administrative expenses) is increased annually based on a cost of living index rather than the actual amount of our costs. Accordingly, the amount of any rent adjustment may not fully offset any increased costs we may incur in providing these services.

Increasing interest rates may adversely affect us and the value of your investment in our Shares.

        There are three principal ways that increasing interest rates may adversely affect us and the value of your investment in our Shares:

•

Funds borrowed under our secured revolving credit facility bear interest at variable rates. If interest rates increase, so will our interest costs, which could adversely affect our cash flow, our ability to

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pay principal and interest on our debt, our cost of refinancing our debt when it becomes due and our ability to pay distributions to you.

•

An increase in interest rates could decrease the amount buyers may be willing to pay for our properties, thereby reducing the market value of our properties and limiting our ability to sell properties or to obtain mortgage financing secured by our properties.



•

We expect to pay regular distributions on our Shares. When interest rates on investments available to investors rise, the market prices of distribution paying securities often decline. Accordingly, if interest rates rise, the market price of your Shares may decline.

Real estate ownership creates risks and liabilities.

        Our business is subject to risks associated with real estate ownership, including:

•

property and casualty losses, some of which may be uninsured;



•

defaults by tenants that lease our properties;



•

the illiquid nature of real estate markets which limits our ability to sell our assets rapidly to respond to changing market conditions;



•

costs that may be incurred relating to property maintenance and repair, and the need to make expenditures due to changes in governmental regulations, including the Americans with Disabilities Act; and



•

asbestos/lead related liabilities and costs of containment or removal and other environmental hazards at our properties for which we may be liable, including those created by prior owners or occupants, existing tenants, adjacent properties or other parties.

Risks Related to Our Relationships with HRP and RMR

As long as HRP retains significant ownership of us, your ability to influence matters requiring shareholder approval will be limited.

        After this offering, HRP will own approximately 35.6% of our outstanding Shares (approximately 34.4% if the underwriters exercise in full their over-allotment option). For so long as HRP continues to retain a significant ownership stake in us, HRP may be able to elect all of the members of our Board of Trustees, including our Independent Trustees, and may effectively control the outcome of shareholder actions. As a result, HRP may have the ability to control all matters affecting us, including:

•

the composition of our Board of Trustees and, through our Board of Trustees, determinations with respect to our management, business plans and policies, including the appointment and removal of our officers;



•

determinations with respect to mergers and other business combinations;



•

our acquisition or disposition of assets;



•

our financing activities;



•

amendments to the transaction agreement;



•

the payment of distributions on our Shares; and



•

the number of Shares available for issuance under our equity incentive plans.

HRP's significant ownership in us and resulting ability to effectively control us may discourage transactions involving a change of control, including transactions in which you as a holder of our Shares might otherwise receive a premium for your Shares over the then current market price.

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HRP's ability to sell its ownership stake in us and speculation about such possible sales may adversely affect the market price of our Shares.

        HRP is not prohibited from selling some or all of its Shares, except that it has agreed (subject to certain exceptions) not to sell or transfer any Shares for 90 days after the date of this prospectus without first obtaining the written consent of Morgan Stanley & Co. Incorporated, and HRP may do so without your approval. HRP has advised us that it does not have any current plans to sell or otherwise dispose of its Shares. However, HRP has a history of successfully divesting certain of its properties into new REITs and then selling or distributing its stake in such REITs over time. So long as HRP continues to retain significant ownership in us, the liquidity and market price of our Shares may be adversely impacted. In addition, speculation by the press, stock analysts, shareholders or others regarding HRP's intention to dispose of its Shares could adversely affect the market price of our Shares. Accordingly, your Shares may be worth less than they would be if HRP did not have significant ownership in us.

Our management structure and our manager's other activities may create conflicts of interest.

        We have no employees. Personnel and services that we require are provided to us under contract by RMR. RMR is authorized to follow broad operating and investment guidelines and, therefore, has great latitude in determining the properties that will be proper investments for us, as well as the individual investment decisions. Our Board of Trustees periodically reviews our operating and investment guidelines and our properties but does not review or approve each decision made by RMR on our behalf. In addition, in conducting periodic reviews, our Board of Trustees relies primarily on information provided to it by RMR. RMR is beneficially owned by our Managing Trustees, Barry Portnoy and Adam Portnoy. Barry Portnoy is Chairman and a director, and Adam Portnoy is President, Chief Executive Officer and a director, of RMR. All of the members of our Board of Trustees, including our Independent Trustees, are members of one or more boards of trustees or directors of various companies managed by RMR. All of our executive officers are also executive officers of RMR. The foregoing individuals may hold equity in or positions with other companies managed by RMR. Such equity ownership and positions by our trustees and officers could create, or appear to create, conflicts of interest with respect to matters involving us, RMR and its affiliates. We cannot assure you that the provisions in our Declaration of Trust or our Bylaws adequately address potential conflicts of interest or that such actual or potential conflicts of interest will be resolved in our favor.

        RMR also acts as the manager for three other publicly traded REITs: HRP, HPT and SNH. RMR also provides management services to other public and private companies, including Five Star Quality Care, Inc., or FVE, which operates senior living communities, including independent living and congregate care communities, assisted living communities, nursing homes and hospitals; and TravelCenters of America LLC, or TravelCenters, which operates and franchises travel centers. These multiple responsibilities to public companies and other businesses could create competition for the time and efforts of RMR and Messrs. Barry Portnoy and Adam Portnoy.

Our management agreements with RMR were negotiated between affiliated parties and may not be as favorable to us as they would have been if negotiated between unaffiliated parties.

        We pay RMR fees based in part upon the historical cost of our investments (including acquisition costs) which at any time may be more or less than the fair market value thereof, the gross rents we collect from tenants and the cost of construction we incur at our properties which is supervised by RMR, plus an incentive fee based upon certain increases in our FFO Per Share (as defined in our management agreements with RMR). For more information, see "Manager." Our fee arrangements with RMR could encourage RMR to advocate acquisitions of properties, to undertake unnecessary construction activities or to overpay for acquisitions or construction. These arrangements may also encourage RMR to discourage sales of properties by us. Our management agreements were negotiated between affiliated parties, and the

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terms, including the fees payable to RMR, may not be as favorable to us as they would have been were they negotiated on an arm's length basis between unaffiliated parties.

Our management agreements with RMR may discourage our change of control.

        Termination of our management agreements with RMR would be a default under our secured revolving credit facility unless approved by a majority of our lenders. RMR is able to terminate its management agreements with us if we experience a change of control. The quality and depth of management available to us by contracting with RMR may not be able to be duplicated by our being a self managed company or by our contracting with unrelated third parties, without considerable cost increases. For these reasons, our management agreements may discourage a change of control of us, including a change of control which might result in payment of a premium for your Shares.

The potential for conflicts of interest as a result of our management structure may provoke dissident shareholder activities that result in significant costs.

        In the past, in particular following periods of volatility in the overall market and the market price of a company's securities, shareholder litigation, dissident trustee nominations and dissident proposals have often been instituted against companies alleging conflicts of interest in business dealings with trustees, affiliated persons and entities. Our relationship with RMR, with Messrs. Barry Portnoy and Adam Portnoy and with RMR affiliates may precipitate such activities. These activities, if instituted against us, could result in substantial costs and a diversion of our management's attention and resources.

Provisions in the transaction agreement and our management agreements with RMR may restrict our investment activities and create conflicts of interest.

        The transaction agreement and our management agreements with RMR restrict our ability to make investments in properties that are within the investment focus of another business now or in the future managed by RMR. In addition, RMR has discretion to determine whether a particular investment opportunity is within our investment focus or that of another business managed by RMR. As a result of these contractual provisions, so long as HRP owns in excess of 10% of our outstanding Shares, we and HRP engage the same manager or we and HRP have one or more common managing trustees, we have limited ability to invest in properties that are within the investment focus of another business managed by RMR or properties that are not, at the time of our investment, properties majority leased to government tenants. These agreements do not restrict our ability, or the ability of other businesses managed by RMR, to lease properties to any particular tenant, and, as a result, we may compete with other businesses managed by RMR for tenants. Our management agreements afford RMR discretion to determine which leasing opportunities to present to us or to other businesses managed by RMR. Accordingly, we may compete with HRP and other businesses managed by RMR for investments in properties that are not within the investment focus of us or another business managed by RMR and for tenants. There is no assurance that any conflicts of interest created by such competition will be resolved in our favor.

We are dependent upon RMR to manage our business and implement our growth strategy.

        Our ability to achieve our business objectives depends on RMR and its ability to manage our properties, source and complete new acquisitions for us on favorable terms and to execute our financing strategy on favorable terms. Because we are externally managed, our business is dependent upon RMR's business contacts, its ability to successfully hire, train, supervise and manage its personnel and its ability to maintain its operating systems. If we lose the services provided by RMR or its key personnel, our business and growth prospects may decline. We may be unable to duplicate the quality and depth of management available to us by becoming a self managed company or by hiring another manager. Also, in the event RMR is unwilling or unable to continue to provide management services to us, our cost of obtaining

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substitute services may be greater than the fees we pay RMR under our management agreements with RMR and as a result our earnings and cash flows may decline.

Risks Related to Our Organization and Structure

Ownership limitations and anti-takeover provisions in our Declaration of Trust and Bylaws, as well as certain provisions of Maryland law, may prevent you from receiving a takeover premium or prevent shareholders from implementing beneficial changes.

        Our Declaration of Trust prohibits any shareholder other than HRP, RMR and their affiliates from owning (directly and by attribution under the Code) more than 9.8% of the number or value of shares of any class or series of our outstanding shares of beneficial interest. This provision of our Declaration of Trust is intended to assist with our REIT compliance under the Code and otherwise to promote our orderly governance. However, this provision also inhibits acquisitions of a significant stake in us and may prevent a change in our control. Additionally, many provisions contained in our governing documents (described below under the caption "Material Provisions of Maryland Law and of Our Declaration of Trust and Bylaws") may further deter persons from attempting to acquire control of us and implement changes that may be beneficial to shareholders, including, for example, provisions relating to:

•

the division of our trustees into three classes, with the term of one class expiring each year, which could delay a change in our control;



•

shareholder voting rights and standards for the election of trustees and other provisions which require larger majorities for approval of actions which are not approved by our trustees than for actions which are approved by our trustees;



•

required qualifications for an individual to serve as a trustee and a requirement that certain of our trustees be "Managing Trustees" and other trustees be "Independent Trustees";



•

limitations on the ability of shareholders to propose nominees for election as trustees and propose other business for a meeting of shareholders;



•

limitations on the ability of shareholders to remove our trustees;



•

the authority of our Board of Trustees, and not our shareholders, to adopt, amend or repeal our Bylaws; and



•

the authority of our Board of Trustees to adopt certain amendments to our Declaration of Trust without shareholder approval, including the authority to increase or decrease the number of authorized Shares, to create new classes or series of shares (including a class or series of shares that could delay or prevent a transaction or a change in our control that might involve a premium for our Shares or otherwise be in the best interests of our shareholders), to increase or decrease the number of shares of any class, and to classify or reclassify any unissued shares from time to time by setting or changing the preferences, conversion or other rights, voting powers, restrictions, limitations as to distributions, qualifications or terms or conditions of redemption of our Shares or any new class of shares created by our Board of Trustees.

Our rights and the rights of our shareholders to take action against our trustees and officers are limited.

        Our Declaration of Trust limits the liability of our trustees and officers to us and our shareholders for money damages to the maximum extent permitted under Maryland law. Under current Maryland law, our trustees and officers will not have any liability to us and our shareholders for money damages other than liability resulting from:

•

actual receipt of an improper benefit or profit in money, property or services; or

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•

active and deliberate dishonesty by the trustee or officer that was established by a final judgment as being material to the cause of action adjudicated.

        Our Bylaws require us to indemnify any present or former trustee or officer, to the maximum extent permitted by Maryland law, who is made or threatened to be made a party to a proceeding by reason of his or her service in that capacity. However, except with respect to proceedings to enforce rights to indemnification, we will indemnify any person referenced in the previous sentence in connection with a proceeding initiated by such person against our company only if such proceeding is authorized by our Board of Trustees. In addition, we may be obligated to pay or reimburse the expenses incurred by our present and former trustees and officers without requiring a preliminary determination of their ultimate entitlement to indemnification. As a result, we and our shareholders may have more limited rights against our trustees and officers than might otherwise exist absent the provisions in our Bylaws or that might exist with other companies, which could limit your recourse in the event of actions not in your best interest.

We may change our operational and investment policies without shareholder approval.

        Our Board of Trustees determines our operational and investment policies and may amend or revise our policies, including our policies with respect to our intention to qualify for taxation as a REIT, acquisitions, dispositions, growth, operations, indebtedness, capitalization and distributions, or approve transactions that deviate from these policies, without a vote of, or notice to, our shareholders. Such policy changes could adversely affect the market value of our Shares and our ability to make distributions to you.

Risks Related to Our Taxation

Our failure to qualify or remain qualified for taxation as a REIT for U.S. federal income tax purposes could have significant adverse consequences.

        We intend to elect and qualify to be taxed as a REIT for U.S. federal income tax purposes commencing with our taxable year ending December 31, 2009, and to maintain such qualification thereafter. Qualifying as a REIT, however, depends on satisfying complex, statutory requirements, for which there are only limited judicial and administrative interpretations. Even if we initially qualify as a REIT, maintaining our status as a REIT will require us to continue to satisfy certain tests concerning, among other things, the nature of our assets, the sources of our income and the amounts we distribute to our shareholders. In order to meet these requirements, it may be necessary for us to sell or forego attractive investments. If we fail to qualify or remain qualified as a REIT, then our ability to raise capital might be adversely affected, we will be in breach under our secured revolving credit facility, we may be subject to material amounts of federal and state income taxes and the value of our Shares likely would decline. In addition, if we lose or revoke our tax status as a REIT for a taxable year, we will be prevented from requalifying as a REIT for the next four taxable years.

Distributions to shareholders generally will not qualify for reduced tax rates.

        The maximum tax rate for dividends payable by U.S. corporations to individual stockholders is 15% through 2010. Distributions paid by REITs, however, are generally not eligible for this reduced rate. The more favorable rates for corporate dividends could cause individual investors to perceive that investment in REITs are less attractive than investment in non-REIT corporations that pay dividends, thereby reducing the demand and market price of our Shares.

Risks Related to this Offering

There is no assurance that we will continue to make distributions.

        We intend to continue to pay regular quarterly distributions to our shareholders. However:

•

our ability to pay distributions will be adversely affected if any of the risks described herein occur;

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•

our payment of distributions is subject to compliance with restrictions contained in our secured revolving credit facility; and



•

any distributions will be made in the discretion of our Board of Trustees and will depend upon various factors that our Board of Trustees deems relevant, including our results of operations, our financial condition, our capital requirements, our FFO, our cash available for distribution, restrictive covenants in our financial or other contractual arrangements, economic conditions and restrictions under Maryland law.

For these reasons, among others, our distribution rate may decline or we may cease making distributions. Also, our distributions may include a return of capital.

The trading market for our common shares may be volatile.

        Our shares have only traded on the NYSE since June 3, 2009. Assuming the underwriters do not exercise their over-allotment option, we are selling 6,500,000 of our Shares in this offering, an amount equal to 30.3% of our shares outstanding prior to the offering. Excluding the Shares owned by HRP and by our management that are subject to the lock up agreement with our underwriters, the 6,500,000 Shares being offered represents approximately 36.1% of the Shares available to trade after this offering. Also, the 3 month average trading volume in our Shares as reported by the NYSE as of December 22, 2009 was only 131,655 Shares per day. We cannot predict what effect this offering may have on the price of our Shares or the volume of transactions involving our Shares in the market. Sales of a substantial amount of our Shares, or the perception that such sales could occur, could adversely affect the liquidity of the market for our Shares or their price. Large price changes or low volume may preclude you from buying or selling our Shares at all, or at any particular price or during a time frame that satisfies your investment objectives.

The combined financial statements of certain government properties wholly owned by HRP, our condensed financial statements and our unaudited pro forma financial statements may not be representative of our results as an independent public company.

        The combined financial statements of certain government properties wholly owned by HRP, our condensed consolidated financial statements and our unaudited pro forma financial statements that are included in this prospectus do not necessarily reflect what our financial position, results of operations or cash flows would have been had we been an independent entity during the entirety of the periods presented. This financial information is not necessarily indicative of what our results of operations, financial position, cash flows or expenses will be in the future. It is impossible for us to accurately estimate all adjustments which may reflect all the significant changes that will occur in our cost structure, funding and operations as a result of our separation from HRP, including potential increased costs associated with reduced economies of scale and increased costs associated with being a separate publicly traded company. We completed our IPO on June 8, 2009 and, since that date, we have been operating as an independent public company. Our financial statements for the nine months ended September 30, 2009 reflect our operations as an independent public company only since June 8, 2009. For additional information, see "Selected Financial and Pro Forma Financial Information" and the combined financial statements of certain government properties wholly owned by HRP, our condensed consolidated financial statements and our unaudited pro forma financial statements appearing elsewhere in this prospectus.

Future sales of our securities may depress the market price of your Shares.

        Subject to applicable law, our Board of Trustees has the authority, without further shareholder approval, to issue additional authorized Shares and other equity and debt securities on the terms and for the consideration it deems appropriate. We cannot predict the effect, if any, of future issuances of our Shares or other securities or the prospect of such issuances, on the market price of our Shares. We also may issue from time to time additional securities in connection with property, portfolio or business

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acquisitions and may grant registration rights in connection with such issuances. Issuances of a substantial amount of our Shares or of senior securities, or the perception that such issuances might occur, could depress the market price of our Shares.

        Upon the closing of this offering, we will have 27,981,350 Shares outstanding, including an aggregate of 9,950,000 Shares owned by HRP. Additionally, up to 1,968,650 Shares may be issued under the Plan to our trustees, executive officers and RMR employees. Assuming our business management agreement with RMR is renewed on its current terms, from and after January 1, 2010, RMR will be eligible to receive incentive compensation payable in our Shares. We, our trustees, our executive officers and HRP have agreed, subject to various exceptions, not to sell or issue any Shares or any securities convertible into or exchangeable for Shares, or file any registration statement with the Securities and Exchange Commission, or the SEC, for 90 days after the date of this prospectus without the prior written consent of Morgan Stanley & Co. Incorporated on behalf of the underwriters. Morgan Stanley & Co. Incorporated, at any time and without notice, may release all or any portion of the Shares subject to the foregoing agreements.

This offering may be dilutive.

        Giving effect to the issuance of Shares in this offering, which may include Shares issued pursuant to a full or partial exercise by the underwriters of their over-allotment option, the receipt of the expected net proceeds and the use of those proceeds, this offering may have a dilutive effect on our expected earnings per Share and FFO per Share. The actual amount of any dilution cannot be determined at this time and will be based on numerous factors.

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WARNING CONCERNING FORWARD LOOKING STATEMENTS

        THIS PROSPECTUS CONTAINS STATEMENTS AND IMPLICATIONS WHICH CONSTITUTE FORWARD LOOKING STATEMENTS WITHIN THE MEANING OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995 AND OTHER FEDERAL SECURITIES LAWS. WHENEVER WE USE WORDS SUCH AS "BELIEVE," "EXPECT," "ANTICIPATE," "INTEND," "PLAN," "ESTIMATE" OR SIMILAR EXPRESSIONS, WE ARE MAKING FORWARD LOOKING STATEMENTS. THESE FORWARD LOOKING STATEMENTS ARE BASED UPON OUR PRESENT INTENT, BELIEFS OR EXPECTATIONS, BUT FORWARD LOOKING STATEMENTS ARE NOT GUARANTEED TO OCCUR AND MAY NOT OCCUR. FORWARD LOOKING STATEMENTS IN THIS PROSPECTUS RELATE TO VARIOUS ASPECTS OF OUR BUSINESS, INCLUDING:

•

OUR ABILITY TO PAY DISTRIBUTIONS TO SHAREHOLDERS AND THE EXPECTED AMOUNTS THEREOF;



•

OUR FUTURE ACQUISITIONS, INCLUDING OUR PENDING ACQUISITION, AND SALES OF PROPERTIES;



•

THE CREDIT QUALITY OF OUR TENANTS;



•

THE LIKELIHOOD THAT OUR TENANTS WILL PAY RENT, RENEW LEASES, SIGN NEW LEASES OR BE AFFECTED BY CYCLICAL ECONOMIC CONDITIONS;



•

OUR ABILITY TO PAY INTEREST ON AND PRINCIPAL OF OUR DEBT;



•

OUR POLICIES AND PLANS REGARDING INVESTMENTS AND FINANCINGS;



•

THE FUTURE AVAILABILITY OF BORROWINGS UNDER OUR SECURED REVOLVING CREDIT FACILITY;



•

OUR ABILITY TO COMPETE EFFECTIVELY;



•

OUR TAX STATUS AS A REIT;



•

OUR ABILITY TO RAISE EQUITY OR DEBT CAPITAL;



•

OUR EXPECTATION THAT WE WILL BENEFIT FINANCIALLY BY PARTICIPATING IN THE INSURANCE COMPANY WITH RMR AND COMPANIES TO WHICH RMR PROVIDES MANAGEMENT SERVICES; AND



•

OTHER MATTERS.

        OUR ACTUAL RESULTS MAY DIFFER MATERIALLY FROM THOSE CONTAINED IN OR IMPLIED BY OUR FORWARD LOOKING STATEMENTS AS A RESULT OF VARIOUS FACTORS. FACTORS THAT COULD HAVE A MATERIAL ADVERSE EFFECT ON OUR FORWARD LOOKING STATEMENTS AND UPON OUR BUSINESS, RESULTS OF OPERATIONS, FINANCIAL CONDITION, FFO, CASH AVAILABLE FOR DISTRIBUTION, CASH FLOWS, LIQUIDITY AND PROSPECTS INCLUDE, BUT ARE NOT LIMITED TO:

•

CHANGES IN THE ECONOMY AND THE CAPITAL MARKETS;



•

COMPETITION WITHIN THE REAL ESTATE INDUSTRY;



•

CHANGES IN PERSONNEL AND LACK OF AVAILABILITY OF QUALIFIED PERSONNEL;



•

ACTUAL AND POTENTIAL CONFLICTS OF INTEREST WITH OUR MANAGING TRUSTEES AND RMR AND THEIR AFFILIATES;



•

CHANGES IN FEDERAL, STATE AND LOCAL LEGISLATION, GOVERNMENTAL REGULATIONS, ACCOUNTING TREATMENT, TAX LAWS AND SIMILAR MATTERS; AND

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•

LIMITATIONS IMPOSED ON OUR BUSINESS AND OUR ABILITY TO SATISFY COMPLEX RULES IN ORDER FOR US TO QUALIFY AS A REIT FOR U.S. FEDERAL INCOME TAX PURPOSES.

FOR EXAMPLE:

•

IF THE AVAILABILITY OF DEBT CAPITAL REMAINS RESTRICTED OR BECOMES MORE RESTRICTED, WE MAY BE UNABLE TO REFINANCE OR REPAY OUR DEBT OBLIGATIONS WHEN THEY BECOME DUE OR ON TERMS WHICH ARE AS FAVORABLE AS WE NOW HAVE;



•

CONTINGENCIES IN OUR ACQUISITIONS MAY CAUSE THESE TRANSACTIONS NOT TO OCCUR OR TO BE DELAYED;



•

WE MAY BE UNABLE TO IDENTIFY PROPERTIES WHICH WE WANT TO BUY OR TO NEGOTIATE ACCEPTABLE PURCHASE PRICES;



•

OUR COMPLETION OF OUR CURRENTLY PENDING ACQUISITION OF A U.S. GOVERNMENT LEASED PROPERTY IN LANDOVER, MARYLAND IS SUBJECT TO VARIOUS CONDITIONS TYPICAL OF LARGE COMMERCIAL REAL ESTATE PURCHASES. AS A RESULT OF ANY FAILURE OF THESE CONDITIONS, THE PROPERTY MAY NOT BE PURCHASED OR THE PURCHASE MAY BE DELAYED;



•

OUR ABILITY TO MAKE FUTURE DISTRIBUTIONS DEPENDS UPON OUR FUTURE EARNINGS;



•

PARTICIPATION IN AIC INVOLVES POTENTIAL FINANCIAL RISKS AND REWARDS TYPICAL OF ANY START UP BUSINESS VENTURE AS WELL AS OTHER FINANCIAL RISKS AND REWARDS SPECIFIC TO INSURANCE COMPANIES. AMONG THE RISKS THAT ARE SPECIFIC TO INSURANCE COMPANIES IS THE RISK THAT AIC MAY NOT BE ABLE TO ADEQUATELY FINANCE CLAIMS. TO THE EXTENT WE PURCHASE INSURANCE FROM AIC IN THE FUTURE AND AIC IS UNABLE TO FINANCE CLAIMS, WE COULD BE UNDERINSURED AND FACE INCREASED COSTS FOR CLAIMS THAT MIGHT OTHERWISE HAVE BEEN FUNDED IF INSURANCE WAS PROCURED WITH OTHER MORE ESTABLISHED INSURERS. ACCORDINGLY, OUR EXPECTED FINANCIAL BENEFITS FROM OUR INITIAL OR FUTURE INVESTMENTS IN AIC MAY BE DELAYED OR MAY NOT OCCUR AND AIC MAY REQUIRE MORE FUNDS THAN WE EXPECT; AND



•

OTHER RISKS MAY ADVERSELY IMPACT US, AS DESCRIBED MORE FULLY IN THIS PROSPECTUS UNDER "RISK FACTORS."

        THESE RESULTS COULD OCCUR DUE TO MANY DIFFERENT CIRCUMSTANCES, SOME OF WHICH ARE BEYOND OUR CONTROL, SUCH AS GOVERNMENT TENANTS' NEEDS FOR LEASED SPACE, OR CHANGES IN THE CAPITAL MARKETS OR THE ECONOMY GENERALLY.

        YOU SHOULD NOT PLACE UNDUE RELIANCE UPON OUR FORWARD LOOKING STATEMENTS.

        EXCEPT AS REQUIRED BY LAW, WE DO NOT UNDERTAKE ANY OBLIGATION TO UPDATE OR CHANGE ANY FORWARD LOOKING STATEMENTS AS A RESULT OF NEW INFORMATION, FUTURE EVENTS OR OTHERWISE.

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USE OF PROCEEDS

        We estimate that the net proceeds we will receive from this offering, after deducting underwriting discounts and commissions and other estimated offering expenses, will be approximately $144.5 million (or approximately $166.2 million if the underwriters fully exercise their over-allotment option), in each case at an assumed public offering price of $23.45 per Share, the closing price of our Shares on the NYSE on December 22, 2009. We expect to use the net proceeds of this offering to reduce amounts outstanding under our secured revolving credit facility and to fund our business activities, including some or all of the purchase price of our pending acquisition. Since the completion of our IPO in June 2009, we borrowed amounts under our secured revolving credit facility to pay for acquisitions, our investment in AIC, certain operating expenses, loan origination costs, IPO costs and for working capital purposes. As of December 22, 2009, the aggregate principal amount outstanding under our secured revolving credit facility was $130.4 million, and such loan carries a per annum interest rate, 5.00% on December 22, 2009, that is calculated at a floating rate based upon LIBOR, subject to a floor, or another specified index plus a spread or margin which will vary depending upon our leverage. Such loan is required to be repaid, together with accrued and unpaid interest thereon, in full by April 24, 2012, but we have a right to extend our secured revolving credit facility for an additional year to April 24, 2013, upon payment of a fee and satisfaction of certain other conditions.

        Morgan Stanley Bank, N.A., an affiliate of Morgan Stanley & Co. Incorporated, is a lender under our secured revolving credit facility and will receive a pro rata portion of the net proceeds from this offering used to reduce the amount outstanding under our secured revolving credit facility.

        Pending use of the net proceeds from this offering as described above, we may invest such proceeds in a variety of capital preservation investments, generally government securities and cash.

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SHARE PRICE RANGE AND DISTRIBUTIONS

        Our Shares are traded on the NYSE under the trading symbol "GOV." On December 22, 2009, the last reported sale price of our Shares, as reported on the NYSE, was $23.45. The following table shows the high and low sales prices for our Shares for the period indicated, as reported on the NYSE, and the cash dividends declared on our Shares during such periods.

        As of December 22, 2009, we had 21,481,350 Shares issued and outstanding. Our issued and outstanding Shares were held by approximately 160 shareholders, which include approximately 50 holders of record. The holders of record include Cede & Co., which holds Shares as nominee for The Depository Trust Company. We estimate that The Depository Trust Company itself holds Shares on behalf of approximately 115 beneficial owners of our Shares as of December 22, 2009.

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DISTRIBUTION POLICY

        We intend to pay regular quarterly distributions to holders of our Shares. Our current quarterly distribution rate is $0.40 per Share ($1.60 on an annualized basis). However, the timing and amount of any distributions will be at the discretion of our Board of Trustees and will depend upon various factors that our Board of Trustees deems relevant, including our results of operations, our financial condition, our capital requirements, our FFO, our cash available for distribution, restrictive covenants in our financial or other contractual arrangements (including our secured revolving credit facility), economic conditions and restrictions under Maryland law. In October 2009, we declared a common share distribution of $0.50 per Share. This distribution consisted of a regular quarterly distribution of $0.40 per Share with respect to the quarter ended September 30, 2009, plus an additional $0.10 per Share reflecting the first 22 days after the completion of our IPO during the prior quarter. In December 2009, we declared a regular quarterly common share distribution of $0.40 per Share with respect to the quarter ended December 31, 2009. This distribution will be paid on or about January 29, 2010 to our shareholders of record on December 21, 2009. Persons who purchase Shares in this offering will not receive this distribution. Subject to the approval of our Board of Trustees, we expect to declare our next regular quarterly distribution shortly before or after March 31, 2010. Shareholders who purchase Shares in this offering and who continue to own those Shares through the record date for any such distribution will receive that distribution.

        U.S. federal income tax law requires that a REIT distribute annually at least 90% of its REIT taxable income, excluding net capital gains, and that it pay tax at regular corporate rates to the extent that it annually distributes less than 100% of its net taxable income including net capital gains. For more information, see "Federal Income Tax Considerations." We anticipate that our cash available for distribution will exceed the annual distribution requirements applicable to REITs. However, under some circumstances, we may be required to pay distributions in excess of cash available for distribution in order to meet these distribution requirements and we may need to borrow funds to make those distributions.

        We cannot assure you that our current distribution rate will be paid or sustained. Any distributions we pay in the future, as well as their timing and frequency, will depend upon our actual results of operations, economic conditions and other factors that could differ materially from our current expectations. Our actual results of operations will be affected by a number of factors, including the rental income we receive from our properties, our operating expenses, interest expense, the ability of our tenants to meet their obligations and unanticipated expenditures. For more information regarding risk factors that could materially adversely affect our actual results of operations, see "Risk Factors." If our properties do not generate sufficient cash flow to allow cash to be distributed by us, we may be required to fund distributions from working capital or borrowings under our secured revolving credit facility, reduce such distributions or issue Shares. Our payment of distributions is subject to compliance with restrictions contained in our secured revolving credit facility.

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CAPITALIZATION

        The following table sets forth (1) our actual cash and cash equivalents and capitalization at September 30, 2009 and (2) our cash and cash equivalents and capitalization on a pro forma basis adjusted to reflect (a) our recent acquisitions closed since September 30, 2009 and the closing of our pending acquisition, (b) the effects of the sale of our Shares by us in this offering at $23.45 per Share for net proceeds of approximately $144.5 million (or approximately $166.2 million if the underwriters fully exercise their over-allotment option), after deducting underwriting discounts and commissions and other estimated offering expenses, and (c) the application of the net proceeds as described in "Use of Proceeds." You should read this table together with "Use of Proceeds," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our financial statements and related notes included elsewhere in this prospectus. Information is presented assuming no exercise and full exercise of the underwriters' over-allotment option.

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SELECTED FINANCIAL AND PRO FORMA FINANCIAL INFORMATION

        You should read the following selected financial and pro forma financial information in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations," the audited Combined Financial Statements of Certain Government Properties (wholly owned by HRPT Properties Trust) and notes thereto, the unaudited Condensed Consolidated Financial Statements of Government Properties Income Trust and notes thereto and the unaudited Pro Forma Financial Statements of Government Properties Income Trust and notes thereto, all included elsewhere in this prospectus. The selected historical consolidated financial information for the nine months ended September 30, 2008 and 2009 and the selected historical balance sheet information as of September 30, 2009 have been derived from our unaudited condensed consolidated financial statements, appearing elsewhere in this prospectus. The selected historical consolidated financial information for the years ended December 31, 2006, 2007 and 2008 and the selected historical consolidated balance sheet information as of December 31, 2007 and 2008 have been derived from the audited combined financial statements of Certain Government Properties (wholly owned by HRPT Properties Trust), appearing elsewhere in this prospectus. The selected historical consolidated financial information for the years ended December 31, 2004 and 2005 and the selected historical consolidated balance sheet information as of December 31, 2004, 2005 and 2006 are derived from unaudited historical financial statements of Certain Government Properties (wholly owned by HRPT Properties Trust), not included in this prospectus. The selected pro forma consolidated financial information for the year ended December 31, 2008 and the nine months ended September 30, 2009 and the selected pro forma consolidated balance sheet information as of September 30, 2009 have been derived from our unaudited pro forma financial statements, appearing elsewhere in this prospectus. The selected financial and pro forma financial information in this section is not intended to replace these audited and unaudited financial statements. In addition, the pro forma balance sheet and income statement data below have been adjusted for our recent acquisitions completed since September 30, 2009, our pending acquisition, this offering and the use of the estimated net proceeds from this offering as described under "Use of Proceeds," and the income statement data has also been adjusted to reflect our formation transactions, our IPO and the application of the net proceeds therefrom and our Nashua, NH acquisition in August 2009. The selected financial and pro forma financial information below and the financial statements included in this prospectus do not necessarily reflect what our results of operations, financial position and cash flows would have been if we had operated as a stand-alone company during all periods presented, and, accordingly, these historical and pro forma results should not be relied upon as an indicator of our future performance.

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