SIR Select Income Reit of Beneficial Interest (delisted)

RISK FACTORS

        Investing in our common shares involves risks. Before purchasing our common shares, you should carefully review the risks described below and the risks described in the "Risk Factors" section of our Annual Report. Additionally, if the Merger is consummated, our common shares will be exchanged for GOV Common Shares and we will distribute the common shares of ILPT that we own to our shareholders in the ILPT Distribution. Additional risks associated with investing in GOV Common Shares and ILPT common shares are described in the "Risk Factors" section of GOV's Annual Report on Form 10-K for the year ended December 31, 2017 and ILPT's Annual Report on Form 10-K for the year ended December 31, 2017, respectively, each of which is incorporated herein by reference. If any of these risks occurs, our business, financial condition, liquidity, results of operations and prospects and our ability to service our debt and make distributions to our shareholders could be materially and adversely affected.

Risks Relating to the Merger and the other Transactions

The exchange ratio is fixed and will not be adjusted for any changes in the market price of either GOV Common Shares or our common shares.

        At the Effective Time, each of our common shares (other than any shares owned by GOV or us or our or GOV's respective wholly owned subsidiaries and in each case not held on behalf of third parties) outstanding immediately prior to the Effective Time will be converted into the right to receive 1.04 newly issued GOV Common Shares, with cash paid in lieu of fractional shares. The exchange ratio is fixed in the Merger Agreement and will not be adjusted for changes in the market price of GOV Common Shares or our common shares. Changes in the market price of GOV Common Shares prior to the consummation of the Merger and the other Transactions will affect the market value of the merger consideration. The market price of GOV Common Shares and our common shares may change as a result of a variety of factors (many of which are beyond GOV's and our control), including the following:

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market reaction to the announcement of the Merger, the issuance of GOV Common Shares in the Merger and the other Transactions and the prospects of the combined company;



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changes in our or GOV's respective businesses, operations, assets, liabilities, financial position and prospects, and with respect to us, ILPT, or in the market's assessments thereof;



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changes in the operating performance of us, GOV, ILPT (with respect to us) or similar companies;



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changes in market valuations of similar companies;



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market assessments of the likelihood that the Merger and the other Transactions will be completed;



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the possibility that persons may engage in short sales of our common shares, GOV Common Shares or ILPT common shares;



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interest rates, general market and economic conditions and other factors generally affecting the price of GOV Common Shares and our common shares;



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federal, state and local legislation, governmental regulation and legal developments in the businesses in which we, GOV and ILPT (with respect to us) operate;



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dissident shareholder activity;



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changes that affect the commercial real estate market generally;

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changes in the United States or global economy or capital, financial or securities markets generally; and



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other factors beyond our, GOV's or ILPT's control, including those described and referred to above under this "Risk Factors" section.

        Changes in the market price of GOV Common Shares or our common shares prior to the consummation of the Merger and the other Transactions will affect the market value of the merger consideration. The market price of GOV Common Shares at the consummation of the Merger may vary from the price on the date the Merger Agreement was executed, on the date hereof and on the date of pricing of this offering. As a result, the market value of the merger consideration represented by the exchange ratio will also vary. Because the Merger will be completed (if at all) after the date hereof and the date of the pricing of this offering, you will not know the exact market price of GOV Common Shares that our shareholders will receive upon consummation of the Merger. You should therefore consider that:

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if the market price of GOV Common Shares increases between the date hereof or the date of the pricing of this offering and the closing of the Merger, purchasers of shares in this offering who continue to hold such shares at the Effective Time will receive GOV Common Shares that have a market value upon consummation of the Merger that is greater than the market value of such shares calculated pursuant to the exchange ratio on the date the Merger Agreement was signed, the date hereof or the date of the pricing of this offering, respectively; and



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if the market price of GOV Common Shares declines between the date hereof or the date of the pricing of this offering and the closing of the Merger, purchasers of shares in this offering who continue to hold such shares at the Effective Time will receive GOV Common Shares that have a market value upon consummation of the Merger that is less than the market value of such shares calculated pursuant to the exchange ratio on the date the Merger Agreement was signed, the date hereof or the date of the pricing of this offering, respectively.

The Merger and the other Transactions are subject to the satisfaction or waiver of a number of conditions, including certain conditions that may not be satisfied, or completed on a timely basis, if at all. Failure to complete the Merger and the other Transactions could have material and adverse effects on us or GOV.

        The consummation of the Merger and the other Transactions is subject to the satisfaction or waiver of a number of conditions, including, among others, the receipt of approval by GOV's shareholders and the receipt of approval by our shareholders, the completion of this offering and the declaration and payment of the ILPT Distribution. These conditions make the completion, and the timing of the completion, of the Merger uncertain. Also, either we or GOV may terminate the Merger Agreement if the Merger is not completed by June 30, 2019, except that this right to terminate the Merger Agreement will not be available to a party if that party failed to fulfill its obligations under the Merger Agreement and that failure was a principal cause of, or, resulted in, the failure of the Merger to be completed on or before such date.

        We and GOV cannot provide assurance that the Merger will be consummated on the terms or timeline currently contemplated, or at all. If the Merger or certain of the other Transactions are not completed on a timely basis, or at all, we and GOV may be adversely affected and subject to a number of risks, including the following:

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we and GOV will be required to pay our respective costs relating to the Merger and the other Transactions, such as legal, accounting, financial advisory and printing fees, whether or not such transactions are completed;

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the time and resources committed by our and GOV's respective management to matters relating to the Merger and the other Transactions could otherwise have been devoted to pursuing other opportunities;



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the market price of GOV Common Shares, our common shares or ILPT common shares could decline to the extent that the current market price reflects, and is positively affected by, a market assumption that the Merger and the other Transactions will be completed; and



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if this offering and/or the ILPT Distribution are completed but the Merger is not ultimately consummated, we and/or GOV, as applicable, may not realize the anticipated benefits of the Merger and, with respect to this offering, GOV will no longer have an equity interest in or any control over us, benefit from our income or receive distributions from us, and, with respect to the ILPT Distribution, we will be a significantly smaller company that will no longer have an equity interest in or any control over ILPT, benefit from ILPT's income or receive distributions from ILPT.

We or GOV may waive one or more of the conditions to the Merger or the other Transactions or otherwise amend or modify the terms of the Merger Agreement or the other Transactions, any of which may be material.

        After the completion of this offering, we or GOV may determine to waive to the extent allowed by applicable law, in whole or in part, one or more of the conditions to our obligations to consummate the Merger or the other Transactions or we or GOV may determine to amend or modify the terms of the Merger Agreement, the Merger or the other Transactions after the completion of this offering. Any such waiver, amendment or modification may be material and may, in certain circumstances, be without re-soliciting shareholder approval. Any determination whether to waive any condition to the Merger or other Transactions or otherwise amend or modify the terms of the Merger Agreement or the other Transactions will be made by GOV or us, as applicable, at the time of such waiver, amendment or modification based on the facts and circumstances as they exist at that time.

The Merger Agreement contains provisions that could discourage a potential competing acquirer of either GOV or us or could result in any competing proposal being at a lower price than it might otherwise be.

        The Merger Agreement contains provisions that, subject to certain exceptions, restrict the ability of each of GOV and us to initiate, solicit, propose, knowingly encourage or knowingly facilitate competing third-party proposals to effect, among other things, a merger, reorganization, share exchange, consolidation or the sale of 20% or more of our or GOV's shares or consolidated net revenues, net income or total assets. In addition, either we or GOV generally have an opportunity to offer to modify the terms of the Merger Agreement in response to any competing superior proposal (as defined in the Merger Agreement) that may be made to the other party before our or GOV's board of trustees, as the case may be, may withdraw or modify its recommendation in response to such superior proposal or terminate the Merger Agreement to enter into a definitive agreement with respect to such superior proposal. These provisions could discourage a potential competing acquirer that might have an interest in acquiring all or a significant part of GOV or us from considering or proposing such an acquisition, even if it were prepared to pay consideration with a higher per share value or implied premium to our shareholders than the value proposed to be received or realized in the Merger and the other Transactions, or might result in a potential competing acquirer proposing to pay a lower price than it might otherwise have proposed to pay.

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Our, GOV's and ILPT's business and property management agreements with RMR LLC contain provisions that could discourage a potential competing acquirer of either GOV or us or could result in any competing proposal being at a significantly lower price than it might otherwise be.

        The termination of our, GOV's or ILPT's business and property management agreements with RMR LLC may require us, GOV or ILPT, as applicable, to pay a substantial termination fee to RMR LLC, including in the case of a termination by us, GOV or ILPT, as applicable, for convenience or for a performance reason or, in the case of a termination by RMR LLC, for good reason. RMR LLC agreed to waive its right to receive payment of the termination fee otherwise due under its business and property management agreements with us upon the termination of those agreements when the Merger is consummated. This waiver by RMR LLC applies only in respect of the Merger and does not apply in respect of any competing proposal or superior proposal (as defined in the Merger Agreement) or other transaction or arrangement. The termination provisions of our, GOV's or ILPT's business and property management agreements with RMR LLC substantially increase the cost to us, GOV and ILPT of terminating these agreements, which may discourage a potential competing acquirer that might have an interest in acquiring all or a significant part of us, GOV or ILPT from considering or proposing such an acquisition or could result in any competing proposal being at a significantly lower price than it might otherwise be.

GOV's ownership of our common shares could discourage a potential competing acquirer of us.

        Because GOV owned approximately 27.8% of our common shares outstanding as of the Record Date, it will have significant influence over the outcome of the proposals voted on at the special meeting of our shareholders. This will be true even though this offering will be completed after the Record Date, unless a new record date for such meeting is set following the completion of this offering. GOV's significant ownership of us as of the Record Date may discourage a potential competing acquirer of us, including transactions in which our shareholders might otherwise receive a premium for their common shares that may reflect a premium or implied value greater than the amounts our shareholders would receive in the Merger and the other Transactions.

Purchasers of our common shares in this offering will not have the right to vote on the Merger.

        GOV's sale of our common shares in this offering will occur after the Record Date we have set for our shareholders entitled to vote at the special meeting of our shareholders on the Merger and the other transactions contemplated by the Merger Agreement to which we are a party. Pursuant to the terms of the Merger Agreement, GOV must vote all of our common shares owned by it, which as of the Record Date represented approximately 27.8% of our outstanding common shares as of such date, in favor of approval of the Merger and the other transactions contemplated by the Merger Agreement to which we are a party. Therefore, unless a new record date for such meeting is set following the completion of this offering, purchasers of our common shares will not have a right to vote with respect to the Merger and the other transactions contemplated by the Merger Agreement to which we are a party.

Completion of the ILPT Distribution is subject to a number of conditions.

        Pursuant to the Merger Agreement, we have agreed, subject to the satisfaction of the other mutual closing conditions, including the receipt of shareholder approval from our shareholders and GOV shareholders as described above, and the condition that no event, change, effect or development has occurred that has had, or would reasonably be expected to have, a material adverse effect for either us or GOV, to declare and, at least one business day prior to the closing date of the Merger, pay the ILPT Distribution. These conditions make the completion, and the timing of the completion, of the ILPT Distribution uncertain. In the event that the conditions to the ILPT Distribution are not satisfied or

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waived, our shareholders, including purchasers of our common shares in this offering, will not receive any ILPT common shares and the Merger may not be consummated.

Completion of the ILPT Distribution is not conditioned upon consummation of the Merger. As a result, there is a risk that the ILPT Distribution will be completed and the Merger will not be consummated, leaving us a significantly smaller company that will no longer benefit from ILPT's income or receive distributions from ILPT.

        It is a condition to the completion of the Merger that we declare, and pay at least one business day prior to the closing date of the Merger, the ILPT Distribution. While completion of the ILPT Distribution is subject to certain conditions as described in the Merger Agreement, including GOV shareholder approval of the issuance of GOV Common Shares in the Merger and our shareholder approval of the Merger and the other transactions contemplated by the Merger Agreement to which we are a party, the ILPT Distribution is not conditioned upon the consummation of the Merger. In the event that the conditions to the ILPT Distribution are satisfied and the ILPT Distribution is completed, there will be a delay between the completion of the ILPT Distribution and the closing of the Merger, and there is a risk that the Merger may not be consummated. If the ILPT Distribution is completed and the Merger is not consummated, we will then be a significantly smaller company that will no longer benefit from ILPT's income or receive distributions from ILPT, which could materially and adversely impact us and our operating results, financial condition and access to, and cost of, capital.

The pendency of the Merger and the other Transactions could adversely affect our and GOV's business and operations.

        During the pendency of the Merger and the other Transactions, due to operating covenants in the Merger Agreement, we and GOV may each be unable to pursue certain strategic transactions, undertake certain significant capital projects, undertake certain significant financing transactions and pursue other actions that are not in the ordinary course of business, even if such actions would prove beneficial to us or GOV, respectively. In addition, some tenants or vendors may delay or defer decisions related to their business dealings with us and/or GOV, which could negatively impact our or GOV's revenues, earnings, cash flows or expenses, regardless of whether the Merger or certain other Transactions are completed.

GOV's shareholders and our shareholders will be diluted by the consummation of the Merger .

        The consummation of the Merger will dilute the ownership position of existing GOV shareholders and result in our shareholders having an ownership stake in GOV that is smaller than their current stake in us. Upon consummation of the Merger, based upon the number of GOV Common Shares and our common shares outstanding on the Record Date, we estimate that the GOV shareholders immediately prior to the Merger (in their capacities as such) will own approximately 51.6% of the GOV Common Shares outstanding as a result of the Merger and the shareholders of us immediately prior to the Merger (in their capacities as such) will own approximately 48.4% of the GOV Common Shares outstanding as a result of the Merger, in each case without taking into account whether any of those GOV shareholders were also shareholders of us at that time. Consequently, our and GOV's shareholders may have less influence over the management and policies of GOV after the Effective Time than they currently exercise over our and GOV's management and policies, respectively.

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Certain of our and GOV's trustees and executive officers and our and GOV's manager, RMR LLC, have interests in the Merger and the other Transactions that are different from, or in addition to, the interests of our shareholders and GOV's shareholders generally, which may create potential conflicts of interest or the appearance thereof.

        The interests of our and GOV's trustees and executive officers and our and GOV's manager, RMR LLC, include, among other things, the continued service as a trustee or executive officer of the combined company following the Merger, certain rights to continuing indemnification and directors' and officers' liability insurance for our Trustees and executive officers, continuation of GOV's management agreements with RMR LLC following the Merger and the potential for increased fees payable to RMR LLC in connection with the Merger and the other Transactions. There is a risk that these interests may influence the trustees and executive officers and RMR LLC to support the Merger and the other Transactions.

The interests of certain of our and GOV's trustees and executive officers and RMR LLC in the Merger and the other Transactions may lead to increased dissident shareholder activity, including litigation, related to the Merger Agreement and the transactions contemplated thereby, which could result in significant costs for us and GOV and materially delay or prevent the completion of the Merger and the other Transactions.

        As noted above, certain of our and GOV's trustees and executive officers and our and GOV's manager, RMR LLC, have interests in the Merger and the other Transactions that are different from, or in addition to, the interests of our and GOV's shareholders generally, which may create potential conflicts of interest or the appearance thereof. These interests of RMR LLC and our and GOV's trustees and executive officers in the Merger and the other Transactions may increase the risk of litigation intended to enjoin or prevent the Merger and the other Transactions and the risk of other dissident shareholder activity related thereto. In the past, and in particular following the announcement of a significant transaction, periods of volatility in the overall market or declines in the market price of a company's securities, shareholder litigation and dissident shareholder proposals have often been instituted against companies alleging conflicts of interest in business dealings with affiliated or related persons and entities. The relationships described above may precipitate such activities by dissident shareholders and, if instituted against us or GOV or our and GOV's respective trustees or executive officers, such activities could result in substantial costs, a material delay or prevention of the Merger or other Transactions and a diversion of management's attention, even if the shareholder action is without merit or unsuccessful.

Lawsuits may be commenced seeking to enjoin or prevent the Merger or the other Transactions or seeking other relief, which may delay or prevent the completion of the Merger or the other Transactions and result in us or GOV incurring substantial costs.

        Public company merger and acquisition transactions are often subject to lawsuits initiated by plaintiff's counsel seeking to enjoin or prevent the transaction or obtain other relief. We, GOV and our respective trustees, officers and advisors may become subject to similar litigation with respect to the Merger or the other Transactions. We are aware that several law firms have indicated that they are investigating the Merger and related matters, including actions taken by our board of trustees, to determine whether they may seek to assert claims. Any such lawsuit could seek, among other things, injunctive or other equitable relief, including a request to rescind parts of the Merger Agreement and to otherwise enjoin the parties from consummating the Merger or the other Transactions, as well as require payment of fees and other costs by the defendants. We, GOV and any other defendant may incur substantial costs defending any such lawsuit, including the distraction of management's attention, even if such lawsuits are without merit or unsuccessful. No assurance can be made as to the outcome of any such lawsuits. If the plaintiffs were successful in obtaining an injunction prohibiting the parties from completing the Merger or the other Transactions or in obtaining other relief, the completion of

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the Merger or other Transactions may be prevented or delayed or their terms could change. Our bylaws provide that a party to such a lawsuit may require that such claims be resolved by arbitration. Plaintiffs may also challenge such arbitration provisions, which may result in additional costs and distractions.

The unaudited pro forma condensed consolidated financial statements in GOV's Current Report on Form 8-K, dated October 2, 2018, which was filed by GOV with the SEC on October 2, 2018 and is incorporated by reference into this prospectus supplement, are presented for illustrative purposes only and may not be reflective of the operating results and financial condition of the combined company following consummation of the Merger and the other Transactions.

        The unaudited pro forma condensed consolidated financial statements incorporated by reference herein from GOV's Current Report on Form 8-K, dated October 2, 2018, are presented for illustrative purposes only and are not necessarily indicative of what the combined company's actual financial position or results of operations would have been had the Merger and the other Transactions been completed on the dates indicated. Further, the combined company's actual results and financial position after the Merger may differ materially and adversely from such unaudited pro forma condensed consolidated financial statements. The unaudited pro forma condensed consolidated financial statements reflect adjustments based upon preliminary estimates of the fair value of assets to be acquired and liabilities to be assumed. The final acquisition accounting will be based upon the actual purchase price and the fair value of our assets and liabilities as of the date of the consummation of the Transactions. In addition, subsequent to the closing date of the Merger, there will be adjustments to the acquisition accounting as additional information becomes available. Accordingly, the final acquisition accounting may differ materially from such pro forma condensed consolidated financial statements.

Shareholders who receive ILPT common shares in the ILPT Distribution may not realize the anticipated benefits of such distribution.

        We expect the ILPT Distribution to provide our shareholders with the opportunity to directly participate in any future growth of ILPT and increase both the liquidity and market price of ILPT common shares. The market price of ILPT common shares may change as a result of a variety of factors (many of which are beyond ILPT's control), including, among other things, changes in the business, operations and operating performance of ILPT, changes in general market and economic conditions and changes in the market valuation of similar companies. As a result of the ILPT Distribution, 45,000,000 additional ILPT common shares will be publicly traded, which may cause the market price of ILPT common shares to be more susceptible to market fluctuations and other adverse events, and the market price of ILPT common shares may decline. Additionally, ILPT's business profile may not fit the investment objectives of certain of our shareholders that receive ILPT common shares in the ILPT Distribution and they may elect to sell the ILPT common shares, which could cause declines in the market price of ILPT's common shares. For these and other reasons, our shareholders who receive ILPT common shares in the ILPT Distribution may not realize some or all of the anticipated benefits of such distribution.

Risks Relating to GOV after Consummation of the Merger and the other Transactions

The market price of GOV Common Shares following the Merger may be affected by factors different from those affecting the price of GOV Common Shares or our common shares before the Merger.

        If the Merger is consummated, based on the number of GOV Common Shares and our common shares outstanding as of the Record Date, the GOV shareholders immediately prior to the Merger will own approximately 51.6% of the GOV Common Shares outstanding as a result of the Merger and our shareholders immediately prior to the Merger will own approximately 48.4% of the GOV Common Shares outstanding as a result of the Merger. The results of operations of GOV and the market price of GOV Common Shares after the Merger may be affected by factors different from those currently

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affecting GOV's or our results of operations and the market price of GOV Common Shares and our common shares. For example, some institutional investors which currently own both our common shares and GOV Common Shares may elect to decrease their ownership in the merged company by selling GOV Common Shares. Accordingly, our and GOV's historical market price and financial results may not be indicative of these matters for GOV after the Merger.

Following the Merger, the principal amount of GOV's indebtedness will increase and GOV may need to incur more debt in the future. Such increase in GOV's indebtedness may increase the risks GOV faces.

        GOV expects to assume our indebtedness upon consummation of the Merger. As of October 1, 2018, GOV had indebtedness of approximately $2.2 billion in principal amount and we had indebtedness of approximately $2.1 billion in principal amount, including ILPT's indebtedness of approximately $428.8 million. GOV's pro forma consolidated indebtedness as of June 30, 2018, after giving effect to the Merger, the other Transactions and the Other Asset Dispositions, would be approximately $2.9 billion in principal amount. GOV's increased indebtedness could have important consequences to holders of GOV Common Shares, including:

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increasing GOV's vulnerability to general adverse economic and industry conditions;



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requiring GOV to use a substantial portion of its cash flow from operations to service its indebtedness, which would reduce the available cash flow to fund working capital, capital expenditures, development projects, and other general corporate purposes and reduce cash available for distributions;



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limiting GOV's ability to obtain additional financing to fund GOV's working capital needs, acquisitions, capital expenditures, or other debt service requirements or for other purposes;



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increasing the costs to GOV of incurring additional debt;



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increasing GOV's exposure to floating interest rates;



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limiting GOV's ability to compete with other companies that are not as highly leveraged, as GOV may be less capable of responding to adverse economic and industry conditions;



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restricting GOV from making strategic acquisitions, developing properties, or exploiting business opportunities;



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restricting the way in which GOV conducts its business because of financial and operating covenants in the agreements governing GOV's existing and future indebtedness;



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exposing GOV to potential events of default (if not cured or waived) under covenants contained in debt instruments that could have a material adverse effect on GOV's business, financial condition, and operating results; and



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limiting GOV's ability to react to changing market conditions in its industry.

        The impact of any of these potential adverse consequences could have a material adverse effect on GOV's results of operations, financial condition and liquidity. If GOV defaults under the agreements governing its indebtedness, GOV may automatically be in default under agreements governing other indebtedness that have cross-default provisions, and further borrowings under GOV's revolving credit facility or term loans will be prohibited and the maturities of outstanding indebtedness under GOV's revolving credit facility, term loans or any other loans may be accelerated.

The Merger or the other Transactions may trigger contractual rights under certain agreements .

        We and GOV are each a party to certain agreements that may trigger prepayment, termination or other rights following a "change in control" or "sale of all or substantially all" of the party's assets.

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Any counterparty to such agreements, or holder of debt securities governed by such agreements, may request modifications of its respective agreements as a condition to granting a waiver or consent under such agreements, or they may elect not to grant a waiver or consent. Although we and GOV believe the Merger and the other Transactions would not trigger such rights, there is no assurance that such counterparties or holders of debt securities will not assert otherwise and seek to exercise any such rights, including termination or repurchase rights where available, that the exercise of any such rights will not result in a material adverse effect on GOV, us or the combined company or that any modifications of such agreements will not result in a material adverse effect on GOV, us or the combined company.

GOV may not complete its plan to sell certain assets to reduce its leverage and any failure to complete such asset sales could adversely affect the combined company's credit profile.

        Prior to the closing of the Merger, GOV expects to complete the sale of 20 properties (50 buildings) containing 3.4 million square feet for aggregate gross proceeds of approximately $440 million from the Other Asset Dispositions that have not yet been completed. One of these properties (one building) and one property portfolio with eight properties (34 buildings) are under contract to be sold for aggregate gross proceeds of $271.5 million and are subject to due diligence and customary closing conditions. One property portfolio with 11 properties (15 buildings) with aggregate estimated gross proceeds of approximately $168.5 million, is under a letter of intent, and consummation of this transaction is subject to negotiation of a binding purchase and sale agreement, including terms related to purchase price, and satisfaction of the conditions contained therein.

        We and GOV have also identified an additional approximately $750 million of assets to be sold by the combined company following the closing of the Merger. Our and GOV's estimated value of $750 million for these properties is based on our and GOV's knowledge of the properties, local markets and multiples on projected cash flows. This estimate involves multiple assumptions and judgements about future events that are inherently uncertain; accordingly, we can provide no assurance regarding the actual gross proceeds that will be realized if these sales are consummated and such amounts may be less than $750 million. Such properties, however, have not yet been marketed for sale by either GOV or us and the combined company may not be able to successfully sell these properties or may sell these properties at prices that are less than their current carrying values.

        GOV and, following the Merger, the combined company expects to use the proceeds from these asset sales to reduce the combined company's leverage. There can be no assurance that GOV, we or the combined company will be able to consummate any such asset sales on favorable terms or at all. Any potential asset sales would be dependent upon a number of factors that may be beyond GOV's, our or the combined company's control, including, among other factors, market conditions, industry trends, the interest of third parties in GOV's, our or the combined company's assets and the availability of financing to potential buyers on reasonable terms.

        Alternatively, in lieu of selling such properties, the combined company may sell some or all of the approximately 2.8 million shares of class A common stock of RMR Inc. that it will own following completion of the Merger. Any such sale would be subject to the sole discretion and approval of the combined company's board of trustees and there can be no assurance that the combined company will be able to consummate any such sale on favorable terms or at all. If GOV, we or the combined company is unable to divest such assets, or if any such divestitures take place on terms less favorable than currently anticipated, the combined company may have greater indebtedness than anticipated, which may negatively impact its credit profile or its ability to meet certain leverage targets, and could therefore impact negatively its ability to enhance its credit profile or maintain its credit rating in the future and/or make attractive acquisitions.

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Each of us and GOV prior to the closing of the Merger expects to, and GOV following the closing of the Merger may, incur substantial costs related to the Merger and the other Transactions.

        Each of us and GOV prior to the closing of the Merger expects to, and GOV following the closing of the Merger may, incur significant costs in connection with the Merger and the other Transactions, and may incur unanticipated costs. While each company has assumed that a certain level of transaction and integration expenses will be incurred, there are factors beyond each of our and GOV's control that could affect the total amount or the timing of those expenses. Many of the expenses that may be incurred, by their nature, are difficult to estimate accurately at the present time. Although we and GOV each expect that the elimination of duplicative costs, as well as the realization of other efficiencies related to the integration of the two businesses, may allow the combined company to offset those incremental expenses over time, the net benefit may not be achieved in the near term, or at all.

Many of the properties of the combined company depend upon a single tenant for all or a majority of its rental income; therefore, GOV's financial condition, including its ability to make distributions to shareholders, may be adversely affected by the bankruptcy or insolvency, a downturn in the business, or a lease termination of a single tenant.

        Approximately 70% of the properties in our portfolio (excluding ILPT) to be acquired by GOV are occupied by only one tenant and, therefore, the success of those properties will be materially dependent on the financial stability of such tenants. Such tenants face competition within their industries and other factors that could reduce their ability to make rent payments. Lease payment defaults by such tenants could cause the combined company to pay distributions at a lower rate than currently expected or to reduce the amount of distributions that it pays to its shareholders. A default by a single or major tenant, the failure of a guarantor to fulfill its obligations or other premature termination of a lease to such a tenant or such tenant's election not to extend a lease upon its expiration could have an adverse effect on the combined company's financial condition, results of operations, liquidity and ability to pay distributions to its shareholders.

GOV shareholders and our shareholders will have a reduced ownership and voting interest after the Merger and will exercise less influence over management.

        GOV shareholders have the right to vote in the election of GOV's board of trustees and on certain other matters affecting GOV, as specified in GOV's declaration of trust, and our shareholders have the right to vote in the election of our Board of Trustees and on certain other matters affecting us, as specified in our declaration of trust. As a result of the issuance of a significant number of new GOV Common Shares in the Merger, it is expected that, immediately after the Merger is completed, based on the number of GOV Common Shares and our common shares outstanding as of the Record Date, the GOV shareholders immediately prior to the Merger will own approximately 51.6% of the GOV Common Shares outstanding as a result of the Merger and our shareholders immediately prior to the Merger will own approximately 48.4% of the GOV Common Shares outstanding as a result of the Merger. Accordingly, after the Merger, the GOV shareholders immediately prior to the Merger will own a smaller proportion of the outstanding GOV Common Shares than the proportion of outstanding GOV Common Shares that they owned at that time and, as a result, they will have less influence on the management and policies of the combined company than they now have on the management and policies of GOV. Also, after the Merger, our shareholders immediately prior to the Merger will own a smaller proportion of the outstanding GOV Common Shares than the proportion of our outstanding common shares that they owned at that time and, as a result, our shareholders immediately prior to the Merger will have less influence on the management and policies of the combined company than they now have on our management and policies.

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The future financial results of GOV will suffer if GOV does not effectively manage its expanded portfolio following the Merger.

        Following the Merger, GOV will have an expanded portfolio and operations and may continue to expand its operations through additional acquisitions and other strategic transactions. As a result, GOV will face competition for tenants in additional markets, may face new challenges in attracting and retaining tenants and will likely compete with more investors for acquisition opportunities. The future success of GOV will depend, in part, upon its ability to attract and retain tenants in these new markets, manage its expansion and disposition opportunities, integrate new operations into its existing business in an efficient and timely manner, successfully monitor its operations and costs, and maintain necessary internal controls. GOV cannot be sure that it will be able to maintain current rents and occupancy at the properties it acquires, that expansion, acquisition or disposition opportunities will be successful, or that GOV will realize any expected revenue enhancements or other benefits from such transactions.

Risks Relating to Taxation

GOV may incur adverse tax consequences if we have failed or fail to qualify for taxation as a REIT for United States federal income tax purposes.

        If we have failed or fail to qualify for taxation as a REIT for United States federal income tax purposes and the Merger is completed, GOV may inherit significant tax liabilities and could lose its qualification for taxation as a REIT should our disqualifying activities continue after the Merger. Even if GOV retains its qualification for taxation as a REIT, if we do not qualify for taxation as a REIT for a taxable year before the Merger or that includes the Merger and if no relief is available, GOV will face serious tax consequences that could substantially reduce its cash available for distribution to its shareholders because:

•

GOV, as successor by merger to us, inherits any corporate income tax liabilities of us, including penalties and interest;



•

GOV would be subject to tax on the built-in gain on each asset of ours existing at the Effective Time if GOV were to dispose of an asset of ours during a specified period (generally five years) following the Effective Time; and



•

GOV, as successor by merger to us, inherits any of our earnings and profits and could be required to pay a special distribution and/or employ applicable deficiency dividend procedures (including interest payments to the United States Internal Revenue Service, or the IRS) to eliminate any earnings and profits accumulated by us for taxable periods for which we did not qualify for taxation as a REIT.

        As a result of these factors, our failure before the Merger to qualify for taxation as a REIT could impair GOV's ability after the Merger to expand its business and raise capital, and could materially adversely affect the value of GOV Common Shares.

        Finally, if there is an adjustment to our real estate investment trust taxable income or dividends paid deductions, GOV could elect to use the deficiency dividend procedure in respect of preserving our REIT qualification. That deficiency dividend procedure could require GOV to make significant distributions to its shareholders and to pay significant interest to the IRS.

REITs are subject to a range of complex organizational and operational requirements.

        As REITs, we and GOV each must distribute to our respective shareholders with respect to each taxable year at least 90% of our REIT taxable income (which does not equal net income, as calculated in accordance with United States generally accepted accounting principles), without regard to the deduction for distributions paid and excluding net capital gain. A REIT must also meet certain

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requirements with respect to the nature of its income and assets and the ownership of its shares. For any taxable year that we or GOV fail to qualify for taxation as a REIT, we or GOV, as applicable, will not be allowed a deduction for distributions paid to our or GOV's shareholders, as applicable, in computing taxable income, and thus would become subject to United States federal income tax as if we or GOV were a regular taxable corporation. In such an event, we or GOV, as the case may be, could be subject to potentially significant tax liabilities. Unless entitled to relief under certain statutory provisions, we or GOV, as the case may be, would also be disqualified from treatment as a REIT for the four taxable years following the year in which we or GOV lost our qualification, and dispositions of assets within five years after requalifying as a REIT could give rise to gain that would be subject to corporate income tax. If we or GOV failed to qualify for taxation as a REIT, the market price of GOV Common Shares may decline, and GOV may need to reduce substantially the amount of distributions to its shareholders because of its potentially increased tax liability.

A portion of one of our shareholder's investment in our common shares may be returned to such shareholder as a taxable dividend.

        As a condition to the closing of the Merger, we agreed, subject to the satisfaction of certain conditions, to declare and pay the ILPT Distribution. The ILPT Distribution will be treated as a distribution by us to our shareholders in the amount of the fair market value of the ILPT common shares distributed. Because we expect the value of our total cash and other distributions for the taxable year in which the ILPT Distribution is paid to exceed our current and accumulated earnings and profits in such year, we expect that a portion of each cash or other distribution (including the ILPT Distribution) will be taxable to each of our shareholders as a taxable dividend and a portion will be treated as a reduction in such shareholder's adjusted tax basis in our shares.

Risks Relating to an Investment in GOV Common Shares Following the Merger

The market price of GOV Common Shares may decline as a result of the Merger.

        The market price of GOV Common Shares may decline as a result of the Merger if GOV does not achieve the perceived benefits of the Merger or the effect of the Merger on GOV's financial results is not consistent with the expectations of financial or industry analysts.

        In addition, upon consummation of the Merger, GOV shareholders and our shareholders will own GOV Common Shares, and GOV will operate an expanded business with a different mix of properties, risks and liabilities. Current GOV shareholders and our shareholders may not wish to continue to invest in GOV as the combined company, or for other reasons may wish to dispose of some or all of their GOV Common Shares. If, following the Effective Time, large amounts of GOV Common Shares are sold, the price of GOV Common Shares could decline.

Following the Merger, the combined company will not continue to pay distributions at or above the rate currently paid by GOV or us.

        Following the Merger, we and GOV expect that the combined company's annual distribution will range between $0.50 and $0.60 per common share of beneficial interest (before giving effect to the one-for-four reverse stock split described above), based on a target payout ratio of 75% of the combined company's projected cash available for distribution, which is below GOV's current annualized distribution of $1.72 per share and our current annualized distribution of $2.04 per share. The combined company may not be able to increase or maintain this expected distribution rate for various reasons, including the following:

•

the combined company may not have enough cash to pay such distributions due to capital spending requirements, or changes in its cash requirements, cash flow or financial position;

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•

decisions on whether, when and in what amounts to pay any future distributions will remain at all times entirely at the discretion of the combined company's board of trustees, which reserves the right to change the combined company's distribution practices at any time and for any reason, subject to applicable REIT requirements; and



•

any of the other risks described herein or in our Annual Report or GOV's Annual Report on Form 10-K for the year ended December 31, 2017.

        The timing, amount and form of any future combined company distributions will be determined at the discretion of the combined company's board of trustees, and the combined company shareholders will have no contractual or other legal right to distributions that have not been declared by the GOV board of trustees.

Risks Related to this Offering and our Common Shares

The market price of our common shares could be negatively affected by the sale of the significant number of shares in this offering.

        GOV is selling 24,918,421 of our common shares in this offering, which represents approximately 27.8% of our outstanding common shares as of June 30, 2018. The sale of this significant number of our common shares could result in a decrease of, and additional volatility in, the market price of our common shares.

The market price of our common shares may be volatile.

        We cannot predict what effect this offering may have on the price of our common shares or the volume of the transactions involving our common shares in the market. Sales of a substantial amount of our common shares, such as the sale contemplated by this prospectus supplement, or the perception that such sales could occur, could adversely affect the liquidity of the market for our common shares or their price. Large price changes or low volume may preclude you from buying or selling our common shares at all, or at any particular price or during a time frame that satisfies your investment objectives.

Even if this offering is completed, the Merger may not be consummated and the ILPT Distribution may not take place, which could have an adverse impact on the market price of our common shares.

        We and GOV are working to consummate the Merger by December 31, 2018, but the Merger is subject to a number of closing conditions. Satisfaction of many of these conditions is beyond our control. If these conditions are not satisfied or waived, the Merger will not be completed. Certain of the conditions that remain to be satisfied include, but are not limited to:

•

the receipt of the approval of the Merger by our shareholders and approval of the issuance of the GOV Common Shares to be issued in the Merger by GOV's shareholders;



•

the absence of any law or order by any governmental authority prohibiting, making illegal, enjoining or otherwise restricting, preventing or prohibiting the consummation of the Merger, the issuance of the GOV Common Shares to be issued in the Merger or the other Transactions;



•

the SEC having declared effective the registration statement on Form S-4 filed by GOV with the SEC to register the GOV Common Shares to be issued in the Merger, and such registration statement not being the subject of any stop order proceedings seeking a stop order;



•

the approval of Nasdaq for the listing of the GOV Common Shares to be issued in the Merger, subject to official notice of issuance;



•

GOV having effected the sale of our common shares offered by GOV by this prospectus supplement and the accompanying prospectus;

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•

our having declared following the receipt of the requisite shareholder approvals described herein and, at least one business day prior to the closing date, paid the ILPT Distribution, subject to the satisfaction of the other mutual closing conditions and the condition that no event, change, effect or development has occurred that has had, or would reasonably be expected to have, a material adverse effect for either GOV or us;



•

the accuracy of all representations and warranties made by GOV and us in the Merger Agreement and performance by GOV and us of our obligations under the Merger Agreement (subject in most cases to materiality or material adverse effect qualifications), and receipt of an officer's certificate from each of GOV and us attesting thereto;



•

the receipt by each of GOV and us of an opinion of our respective tax counsel to the effect that (i) the Merger will qualify as a reorganization within the meaning of Section 368(a) of the IRC, and (ii) we and GOV will each be a party to that reorganization within the meaning of Section 368(b) of the IRC; and



•

the receipt by each of GOV and us of an opinion of counsel dated as of the closing date of the Merger regarding such party's qualification for taxation as a REIT.

        As a result of the aforementioned conditions, the Merger may not close as scheduled or at all. In addition, either we or GOV may terminate the Merger Agreement under certain circumstances. The closing of this offering is not conditioned on, and is expected to be consummated before, the closing of the Merger. Accordingly, if you decide to purchase our common shares in this offering, you should do so recognizing that we may not complete the Merger. Additionally, the anticipated ILPT Distribution will only be made if certain conditions are satisfied, including requisite shareholder approvals. If a new record date is set for the special meeting, GOV will no longer be able to vote its 27.8% of our outstanding common shares owned as of the Record Date, which may result in the requisite shareholder approval not being obtained. If the required approvals of our shareholders and GOV's shareholders are not obtained, we do not expect that we will complete the ILPT Distribution. The market price of our common shares may be influenced by the value of the GOV Common Shares and the ILPT common shares that will be received by our shareholders if the Transactions are consummated. If the Transactions are not consummated, our shareholders will not receive GOV Common Shares or the ILPT Distribution, and the market price of our common shares could decrease substantially. Failure to complete the Merger or any delays in completing the Merger could have an adverse impact on our future business, operations and results of operations and could negatively impact the market price of our common shares.

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DISTRIBUTIONS

SIR Cash Distributions

        Our current cash distribution rate to shareholders is $0.51 per share per quarter, or $2.04 per share per year. Our distribution rate is set and reset from time to time by our Board of Trustees. The timing, amount and form of distributions are determined 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, debt and equity capital available to us, our expectation of our future capital requirements and operating performance, our FFO, our normalized FFO, our receipt of distributions from ILPT, restrictive covenants in our financing or other contractual arrangements (including those in our credit agreement and senior notes indenture and its supplements), tax law requirements to maintain our qualification for taxation as a REIT, restrictions under Maryland law and our expected needs and availability of cash to pay our obligations. Therefore, we cannot assure you that we will continue to pay distributions in the future or that the amount of any distributions we do pay will not decrease.

        Subject to declaration by our Board of Trustees, we expect our next quarterly distribution to be declared in October 2018 and paid in November 2018, assuming the Merger has not been completed by such time. In addition, we are permitted under the Merger Agreement, upon prior notice to GOV, to declare and pay a pro rata cash quarterly distribution for the portion of the quarterly period ending on the closing date of the Merger. The decision to declare such a pro rata distribution will be determined at the discretion of our Board of Trustees, and our shareholders do not have any contractual or other legal right to such a distribution. Purchasers of common shares in this offering who continue to hold common shares on the record date(s) relating to any such distribution(s) will be entitled to receive such distribution(s) on the corresponding payment date.

ILPT Distribution

        As a condition to the closing of the Merger, we have agreed that we will, subject to the satisfaction or waiver of certain conditions, declare and, at least one business day prior to the Merger, pay, the ILPT Distribution. If such distribution is declared by our Board of Trustees and paid by us, purchasers of common shares in this offering who continue to hold common shares on the record date relating to the ILPT Distribution will be entitled to receive ILPT common shares. The characterization of this distribution will not be ultimately determined until after the close of the taxable year in which the ILPT Distribution has occurred. However, assuming that the ILPT Distribution occurs in 2018 and that the price of the ILPT common shares when distributed is approximately the same as on October 2, 2018, then it is expected that approximately half of our cash and other distributions for all of 2018 (including the ILPT Distribution) will be a nontaxable return of capital, and the balance will largely be a capital gain dividend, with approximately 5% of the total distribution comprising an ordinary REIT dividend. Nontaxable returns of capital are generally nontaxable to both U.S. and non-U.S. shareholders, while capital gain dividends are generally nontaxable to non-U.S. shareholders and taxable at preferential rates to certain U.S. shareholders; nevertheless, because withholding rates and policies are complex and very dependent upon the discretion of applicable withholding agents, withholding may apply to our cash and other distributions (including the ILPT Distribution) in excess of the substantive tax liability applicable to such distributions, and the applicable shareholder may have to claim a refund from the IRS to receive the overwithheld amounts.

The Combined Company—Expected Distributions

        If the Merger is completed and you receive GOV Common Shares in exchange for your SIR common shares, you will not receive distributions at the same rate that you did as a SIR shareholder prior to the Merger. We and GOV expect that the combined company's annual distribution will range

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between $0.50 and $0.60 per common share (before giving effect to the one-for-four reverse stock split described above), based on a target payout ratio of 75% of the combined company's projected cash available for distribution after the proposed property sales of up to $750 million. The timing, amount and form of any future combined company distributions will be determined at the discretion of the combined company's board of trustees, and the combined company's shareholders will have no contractual or other legal right to distributions that have not been declared by the combined company's board of trustees. See "Risk Factors—Risks Relating to an Investment in GOV Common Shares Following the Merger—Following the Merger, the combined company will not continue to pay distributions at or above the rate currently paid by GOV or us."

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RISK FACTORS

        Investing in our securities involves risks. You should carefully review the risk factors contained under the heading "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2017, or our Annual Report, and any risk factors that we may describe in our Quarterly Reports on Form 10-Q or Current Reports on Form 8-K filed subsequently to our Annual Report, which risk factors are incorporated by reference in this prospectus, the information contained under the heading "Warning Concerning Forward Looking Statements" in this prospectus or under any similar heading in any applicable prospectus supplement or in any document incorporated herein or therein by reference, any specific risk factors discussed under the caption "Risk Factors" in any applicable prospectus supplement or in any document incorporated herein or therein by reference and the other information contained in, or incorporated by reference in, this prospectus or any applicable prospectus supplement before making an investment decision. If any such risks occur, our business, financial condition or results of operations could be materially harmed, the market price of our securities could decline and you could lose all or part of your investment.

WARNING CONCERNING FORWARD LOOKING STATEMENTS

         THIS PROSPECTUS, INCLUDING THE DOCUMENTS THAT ARE INCORPORATED HEREIN BY REFERENCE, CONTAINS STATEMENTS THAT CONSTITUTE FORWARD LOOKING STATEMENTS WITHIN THE MEANING OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995 AND OTHER SECURITIES LAWS. ALSO, WHENEVER WE USE WORDS SUCH AS "BELIEVE", "EXPECT", "ANTICIPATE", "INTEND", "PLAN", "ESTIMATE", "WILL", "MAY" AND NEGATIVES OR DERIVATIVES OF THESE 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 RELATE TO VARIOUS ASPECTS OF OUR BUSINESS, INCLUDING:

•

OUR AND GOV'S ABILITY TO COMPLETE THE TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT, INCLUDING THE MERGER, THE SECONDARY SALE AND THE ILPT DISTRIBUTION,

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THE LIKELIHOOD THAT OUR TENANTS WILL PAY RENT OR BE NEGATIVELY AFFECTED BY CYCLICAL ECONOMIC CONDITIONS,



•

THE LIKELIHOOD THAT OUR TENANTS WILL RENEW OR EXTEND THEIR LEASES OR THAT WE WILL BE ABLE TO OBTAIN REPLACEMENT TENANTS,



•

OUR ACQUISITIONS OF PROPERTIES,



•

OUR SALES OF PROPERTIES,



•

OUR ABILITY TO COMPETE FOR ACQUISITIONS AND TENANCIES EFFECTIVELY,



•

THE LIKELIHOOD THAT OUR RENTS WILL INCREASE WHEN WE RENEW OR EXTEND OUR LEASES, WHEN WE ENTER NEW LEASES, OR WHEN OUR RENTS RESET, INCLUDING RENT RESETS AT OUR SUBSIDIARY, ILPT'S, HAWAII PROPERTIES,



•

OUR ABILITY TO PAY DISTRIBUTIONS TO OUR SHAREHOLDERS AND TO SUSTAIN THE AMOUNT OF SUCH DISTRIBUTIONS,



•

THE FUTURE AVAILABILITY OF BORROWINGS UNDER OUR REVOLVING CREDIT FACILITY OR ILPT'S REVOLVING CREDIT FACILITY,



•

OUR POLICIES AND PLANS REGARDING INVESTMENTS, FINANCINGS AND DISPOSITIONS,



•

OUR ABILITY TO RAISE DEBT OR EQUITY CAPITAL,



•

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



•

OUR ABILITY TO APPROPRIATELY BALANCE OUR USE OF DEBT AND EQUITY CAPITAL,



•

OUR CREDIT RATINGS,



•

OUR EXPECTATION THAT OUR SHAREHOLDERS WILL BENEFIT FROM OUR OWNERSHIP INTEREST IN AND OTHER RELATIONSHIPS WITH ILPT,



•

OUR EXPECTATION THAT WE BENEFIT FROM OUR OWNERSHIP INTEREST IN AND OTHER RELATIONSHIPS WITH THE RMR GROUP INC., OR RMR INC.,



•

OUR EXPECTATION THAT WE BENEFIT FROM OUR OWNERSHIP INTEREST IN AND OTHER RELATIONSHIPS WITH AFFILIATES INSURANCE COMPANY, OR AIC, AND FROM OUR PARTICIPATION IN INSURANCE PROGRAMS ARRANGED BY AIC,



•

OUR QUALIFICATION FOR TAXATION AS A REIT, AND ILPT'S ABILITY TO QUALIFY AND MAINTAIN ITS QUALIFICATION FOR TAXATION AS A REIT,



•

THE CREDIT QUALITIES OF OUR TENANTS, 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, FUNDS FROM OPERATIONS ATTRIBUTED TO US, NORMALIZED FUNDS FROM OPERATIONS ATTRIBUTED TO US, NET OPERATING INCOME, CASH FLOWS, LIQUIDITY AND PROSPECTS INCLUDE, BUT ARE NOT LIMITED TO:

•

THE IMPACT OF CONDITIONS AND CHANGES IN THE ECONOMY AND THE CAPITAL MARKETS ON US AND OUR TENANTS,

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•

COMPETITION WITHIN THE REAL ESTATE INDUSTRY, PARTICULARLY IN THOSE MARKETS IN WHICH OUR PROPERTIES ARE LOCATED,



•

COMPLIANCE WITH, AND CHANGES TO, FEDERAL, STATE AND LOCAL LAWS AND REGULATIONS, ACCOUNTING RULES, TAX LAWS AND SIMILAR MATTERS,



•

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



•

ACTUAL AND POTENTIAL CONFLICTS OF INTEREST WITH OUR RELATED PARTIES, INCLUDING OUR MANAGING TRUSTEES, RMR LLC, RMR INC., ILPT, GOV, AIC AND OTHERS AFFILIATED WITH THEM, AND



•

ACTS OF TERRORISM, OUTBREAKS OF SO CALLED PANDEMICS OR OTHER MANMADE OR NATURAL DISASTERS BEYOND OUR CONTROL.

FOR EXAMPLE:

•

THE CLOSING OF OUR MERGER WITH GOV IS SUBJECT TO THE SATISFACTION OR WAIVER OF CONDITIONS, INCLUDING THE RECEIPT OF REQUISITE APPROVALS BY OUR AND GOV'S SHAREHOLDERS AND THE COMPLETION OF THE SECONDARY SALE AND THE ILPT DISTRIBUTION. WE CANNOT BE SURE THAT ANY OR ALL OF SUCH CONDITIONS WILL BE SATISFIED OR WAIVED. ACCORDINGLY, THE MERGER MAY NOT CLOSE WHEN EXPECTED OR AT ALL, OR THE TERMS OF THE MERGER AND THE OTHER TRANSACTIONS MAY CHANGE,



•

AS NOTED ABOVE, THE MERGER WILL REQUIRE APPROVAL OF OUR SHAREHOLDERS AND THE ISSUANCE OF GOV COMMON SHARES IN THE MERGER WILL REQUIRE APPROVAL OF THE GOV SHAREHOLDERS. SUCH APPROVALS WILL BE SOLICITED BY A JOINT PROXY STATEMENT/PROSPECTUS INCLUDED AS PART OF THE REGISTRATION STATEMENT ON FORM S-4 FILED BY GOV WITH THE SEC ON SEPTEMBER 28, 2018. THE REGISTRATION STATEMENT ON FORM S-4 MUST BE REVIEWED AND DECLARED EFFECTIVE BY THE SEC BEFORE THE JOINT PROXY STATEMENT/PROSPECTUS CAN BE MAILED TO OUR SHAREHOLDERS AND GOV'S SHAREHOLDERS. THE AMOUNT OF TIME IT TAKES FOR THE SEC TO REVIEW AND DECLARE THE REGISTRATION STATEMENT EFFECTIVE IS BEYOND OUR AND GOV'S CONTROL. ACCORDINGLY, WE CANNOT BE SURE THAT THE MERGER AND THE OTHER TRANSACTIONS WILL BE CONSUMMATED WITHIN A SPECIFIED TIME PERIOD OR AT ALL OR THAT THE TERMS OF THE MERGER AND THE OTHER TRANSACTIONS WILL NOT CHANGE,



•

GOV OWNS A SIGNIFICANT NUMBER OF OUR COMMON SHARES AND ITS ABILITY TO COMPLETE THE SALE OF ALL OF THOSE SHARES AS CONTEMPLATED BY THE MERGER AGREEMENT IS SUBJECT TO MARKET CONDITIONS AND OTHER FACTORS, SOME OF WHICH ARE BEYOND GOV'S AND OUR CONTROL. AS A RESULT, THE SECONDARY SALE MAY BE DELAYED OR MAY NOT BE COMPLETED,



•

THE ILPT DISTRIBUTION IS SUBJECT TO THE SATISFACTION OF SPECIFIED CONDITIONS, INCLUDING AMONG OTHER THINGS, OBTAINING THE REQUISITE SHAREHOLDER APPROVALS WITH RESPECT TO THE MERGER. WE CANNOT BE SURE WHEN OR IF THOSE CONDITIONS WILL BE SATISFIED OR THAT THE ILPT DISTRIBUTION WILL OCCUR,

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•

COMPLETION OF THE ILPT DISTRIBUTION IS NOT CONDITIONED UPON CONSUMMATION OF THE MERGER. AS A RESULT, THERE IS A RISK THAT THE ILPT DISTRIBUTION WILL BE COMPLETED AND THE MERGER WILL NOT BE CONSUMMATED, LEAVING US A SIGNIFICANTLY SMALLER COMPANY THAT WILL NO LONGER BENEFIT FROM ILPT'S INCOME OR RECEIVE DISTRIBUTIONS FROM ILPT,



•

THE TRANSACTIONS CONTEMPLATED BY THE MERGER AGREEMENT AND THE TERMS THEREOF WERE EVALUATED, NEGOTIATED AND RECOMMENDED TO EACH OF OUR AND GOV'S BOARD OF TRUSTEES BY A SPECIAL COMMITTEE OF OUR AND GOV'S BOARD OF TRUSTEES, RESPECTIVELY, EACH COMPRISED SOLELY OF OUR AND GOV'S DISINTERESTED, INDEPENDENT TRUSTEES, RESPECTIVELY, AND WERE SEPARATELY APPROVED AND ADOPTED BY OUR AND GOV'S INDEPENDENT TRUSTEES AND BY OUR AND GOV'S BOARD OF TRUSTEES, AND UBS SECURITIES LLC AND CITIGROUP GLOBAL MARKETS INC. ACTED AS A FINANCIAL ADVISOR TO US AND GOV, RESPECTIVELY. DESPITE THIS PROCESS, WE COULD BE SUBJECT TO CLAIMS CHALLENGING THE MERGER OR OTHER TRANSACTIONS OR OUR ENTRY INTO THE MERGER AND RELATED AGREEMENTS BECAUSE OF THE MULTIPLE RELATIONSHIPS AMONG US, GOV, ILPT, RMR LLC AND THEIR RELATED PERSONS AND ENTITIES OR OTHER REASONS, AND DEFENDING EVEN MERITLESS CLAIMS COULD BE EXPENSIVE AND DISTRACTING TO MANAGEMENT,



•

OUR ABILITY TO MAKE FUTURE DISTRIBUTIONS TO OUR SHAREHOLDERS AND TO MAKE PAYMENTS OF PRINCIPAL AND INTEREST ON OUR INDEBTEDNESS DEPENDS UPON A NUMBER OF FACTORS, INCLUDING OUR FUTURE EARNINGS, THE CAPITAL COSTS WE INCUR TO LEASE OUR PROPERTIES, OUR WORKING CAPITAL REQUIREMENTS AND OUR RECEIPT OF DISTRIBUTIONS FROM ILPT. WE MAY BE UNABLE TO PAY OUR DEBT OBLIGATIONS OR TO MAINTAIN OUR CURRENT RATE OF DISTRIBUTIONS ON OUR COMMON SHARES AND FUTURE DISTRIBUTIONS MAY BE REDUCED OR ELIMINATED,



•

OUR ABILITY TO GROW OUR BUSINESS AND INCREASE OUR DISTRIBUTIONS DEPENDS IN LARGE PART UPON OUR ABILITY TO BUY PROPERTIES AND LEASE THEM FOR RENTS, LESS THEIR PROPERTY OPERATING COSTS, THAT EXCEED OUR CAPITAL COSTS. WE MAY BE UNABLE TO IDENTIFY PROPERTIES THAT WE WANT TO ACQUIRE OR TO NEGOTIATE ACCEPTABLE PURCHASE PRICES, ACQUISITION FINANCING OR LEASE TERMS FOR NEW PROPERTIES,



•

CONTINGENCIES IN OUR ACQUISITION AND SALE AGREEMENTS MAY NOT BE SATISFIED AND ANY EXPECTED ACQUISITIONS AND SALES MAY NOT OCCUR, MAY BE DELAYED OR THE TERMS OF SUCH TRANSACTIONS MAY CHANGE,



•

RENTS THAT WE CAN CHARGE AT OUR PROPERTIES MAY DECLINE BECAUSE OF CHANGING MARKET CONDITIONS OR OTHERWISE,



•

MOST OF ILPT'S HAWAII PROPERTIES ARE LANDS LEASED FOR RENTS THAT ARE PERIODICALLY RESET BASED ON THEN CURRENT FAIR MARKET VALUES. REVENUES FROM ILPT'S PROPERTIES IN HAWAII HAVE GENERALLY INCREASED DURING OUR AND OUR PREDECESSOR'S AND ILPT'S OWNERSHIP AS THE LEASES FOR THOSE PROPERTIES HAVE BEEN RESET OR RENEWED. ALTHOUGH ILPT EXPECTS THAT RENTS FOR ITS HAWAII PROPERTIES WILL INCREASE IN THE FUTURE, ILPT CANNOT BE SURE THEY WILL. FUTURE RENTS FROM THESE PROPERTIES COULD DECREASE OR NOT INCREASE TO THE EXTENT THEY HAVE IN THE PAST,

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•

WE MAY NOT SUCCEED IN FURTHER DIVERSIFYING OUR REVENUE SOURCES AND ANY DIVERSIFICATION WE MAY ACHIEVE MAY NOT MITIGATE OUR PORTFOLIO RISKS OR IMPROVE THE SECURITY OF OUR REVENUES OR OUR OPERATING PERFORMANCE,



•

ILPT'S POSSIBLE REDEVELOPMENT OF CERTAIN OF ITS HAWAII PROPERTIES MAY NOT BE REALIZED OR BE SUCCESSFUL,



•

OUR LEASING RELATED OBLIGATIONS MAY COST MORE OR LESS AND MAY TAKE LONGER TO COMPLETE THAN WE EXPECT, AND OUR LEASING RELATED OBLIGATIONS MAY INCREASE,



•

THE UNEMPLOYMENT RATE OR ECONOMIC CONDITIONS IN AREAS WHERE OUR PROPERTIES ARE LOCATED MAY BECOME WORSE IN THE FUTURE. SUCH CIRCUMSTANCES OR OTHER CONDITIONS MAY REDUCE DEMAND FOR LEASING OFFICE AND INDUSTRIAL SPACE. IF THE DEMAND FOR LEASING OFFICE AND INDUSTRIAL SPACE IS REDUCED, WE MAY BE UNABLE TO RENEW LEASES WITH OUR TENANTS AS LEASES EXPIRE OR ENTER INTO NEW LEASES AT RENTAL RATES AS HIGH AS EXPIRING RENTS AND OUR FINANCIAL RESULTS MAY DECLINE,



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OUR BELIEF THAT THERE IS A LIKELIHOOD THAT TENANTS MAY RENEW OR EXTEND OUR LEASES WHEN THEY EXPIRE WHENEVER THEY HAVE MADE SIGNIFICANT INVESTMENTS IN THE LEASED PROPERTIES, OR BECAUSE THOSE PROPERTIES MAY BE OF STRATEGIC IMPORTANCE TO THEM, MAY NOT BE REALIZED,



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SOME OF OUR TENANTS MAY NOT RENEW EXPIRING LEASES, AND WE MAY BE UNABLE TO OBTAIN NEW TENANTS TO MAINTAIN OR INCREASE THE HISTORICAL OCCUPANCY RATES OF, OR RENTS FROM, OUR PROPERTIES,



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WE MAY INCUR SIGNIFICANT COSTS TO PREPARE A PROPERTY FOR A TENANT, PARTICULARLY FOR SINGLE TENANT PROPERTIES,



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INCREASING DEVELOPMENT OF INDUSTRIAL AND LOGISTICS PROPERTIES MAY REDUCE THE DEMAND FOR, AND ILPT'S RENTS FROM, ILPT'S PROPERTIES,



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WE INTEND TO CONDUCT OUR BUSINESS ACTIVITIES IN A MANNER THAT WILL AFFORD US REASONABLE ACCESS TO CAPITAL FOR INVESTMENT AND FINANCING ACTIVITIES. HOWEVER, WE MAY NOT SUCCEED IN THIS REGARD AND WE MAY NOT HAVE REASONABLE ACCESS TO CAPITAL,



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CONTINUED AVAILABILITY OF BORROWINGS UNDER OUR REVOLVING CREDIT FACILITY AND ILPT'S REVOLVING CREDIT FACILITY IS SUBJECT TO US AND ILPT, AS THE CASE MAY BE, SATISFYING CERTAIN FINANCIAL COVENANTS AND OTHER CREDIT FACILITY CONDITIONS THAT WE AND ILPT MAY BE UNABLE TO SATISFY,



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ACTUAL COSTS UNDER OUR REVOLVING CREDIT FACILITY AND ILPT'S REVOLVING CREDIT FACILITY OR OTHER FLOATING RATE DEBT WILL BE HIGHER THAN LIBOR PLUS A PREMIUM BECAUSE OF FEES AND EXPENSES ASSOCIATED WITH SUCH DEBT,



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WE MAY BE UNABLE TO REPAY OUR DEBT OBLIGATIONS WHEN THEY BECOME DUE,



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THE MAXIMUM BORROWING AVAILABILITY UNDER OUR REVOLVING CREDIT FACILITY MAY BE INCREASED TO UP TO $1.85 BILLION IN CERTAIN CIRCUMSTANCES AND THE MAXIMUM BORROWING AVAILABILITY UNDER ILPT'S REVOLVING CREDIT FACILITY MAY BE INCREASED TO UP TO $1.5 BILLION IN CERTAIN CIRCUMSTANCES. HOWEVER, INCREASING THE MAXIMUM BORROWING AVAILABILITY UNDER OUR

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REVOLVING CREDIT FACILITY OR ILPT'S REVOLVING CREDIT FACILITY IS SUBJECT TO US AND ILPT, AS THE CASE MAY BE, OBTAINING ADDITIONAL COMMITMENTS FROM LENDERS, WHICH MAY NOT OCCUR,

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WE HAVE THE OPTION TO EXTEND THE MATURITY DATE OF OUR REVOLVING CREDIT FACILITY, AND ILPT HAS THE OPTION TO EXTEND THE MATURITY DATE OF ITS REVOLVING CREDIT FACILITY, UPON PAYMENT OF A FEE AND MEETING OTHER CONDITIONS, RESPECTIVELY, HOWEVER, THE APPLICABLE CONDITIONS MAY NOT BE MET,



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WE RECEIVED AN ASSESSMENT FROM THE STATE OF WASHINGTON FOR REAL ESTATE EXCISE TAX, INTEREST AND PENALTIES OF $2.8 MILLION ON CERTAIN PROPERTIES WE ACQUIRED IN CONNECTION WITH OUR ACQUISITION OF COLE CORPORATE INCOME TRUST, INC. IN JANUARY 2015. ALTHOUGH WE BELIEVE WE ARE NOT LIABLE FOR THIS TAX AND ARE DISPUTING THIS ASSESSMENT, WE MAY NOT SUCCEED IN HAVING ALL OR ANY PART OF THIS ASSESSMENT NULLIFIED,



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THE PREMIUMS USED TO DETERMINE THE INTEREST RATE PAYABLE ON OUR REVOLVING CREDIT FACILITY AND ILPT'S REVOLVING CREDIT FACILITY, THE FACILITY FEE PAYABLE ON OUR REVOLVING CREDIT FACILITY AND THE UNUSED FEE PAYABLE ON ILPT'S REVOLVING CREDIT FACILITY ARE BASED ON OUR CREDIT RATINGS AND ILPT'S LEVERAGE, RESPECTIVELY. FUTURE CHANGES IN OUR CREDIT RATINGS AND ILPT'S LEVERAGE MAY CAUSE THE INTEREST AND FEES WE AND ILPT PAY, RESPECTIVELY, TO INCREASE,



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RMR INC. MAY REDUCE THE AMOUNT OF DISTRIBUTIONS TO ITS SHAREHOLDERS, INCLUDING US,



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ILPT MAY REDUCE THE AMOUNT OF DISTRIBUTIONS TO ITS SHAREHOLDERS, INCLUDING US, AND INCLUDING AFTER THE ILPT DISTRIBUTION,



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THE BUSINESS AND PROPERTY MANAGEMENT AGREEMENTS BETWEEN US AND RMR LLC HAVE CONTINUING 20 YEAR TERMS. HOWEVER, THOSE AGREEMENTS PERMIT EARLY TERMINATION IN CERTAIN CIRCUMSTANCES. ACCORDINGLY, WE CANNOT BE SURE THAT THESE AGREEMENTS WILL REMAIN IN EFFECT FOR CONTINUING 20 YEAR TERMS, AND



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WE BELIEVE THAT OUR RELATIONSHIPS WITH OUR RELATED PARTIES, INCLUDING RMR LLC, RMR INC., ILPT, GOV, AIC AND OTHERS AFFILIATED WITH THEM MAY BENEFIT US AND PROVIDE US WITH COMPETITIVE ADVANTAGES IN OPERATING AND GROWING OUR BUSINESS. HOWEVER, THE ADVANTAGES WE BELIEVE WE MAY REALIZE FROM THESE RELATIONSHIPS MAY NOT MATERIALIZE.

         CURRENTLY UNEXPECTED RESULTS COULD OCCUR DUE TO MANY DIFFERENT CIRCUMSTANCES, SOME OF WHICH ARE BEYOND OUR CONTROL, SUCH AS ACTS OF TERRORISM, NATURAL DISASTERS, CHANGES IN OUR TENANTS' FINANCIAL CONDITIONS, THE MARKET DEMAND FOR LEASED SPACE OR CHANGES IN CAPITAL MARKETS OR THE ECONOMY GENERALLY. MANY OF THESE FACTORS ALSO APPLY TO ILPT AND ITS BUSINESS, OPERATIONS, LIQUIDITY AND FINANCIAL CONDITION, THE REALIZATION OF WHICH COULD MATERIALLY AND ADVERSELY AFFECT US, PARTICULARLY IF ILPT IS UNABLE TO MAKE DISTRIBUTIONS TO ITS SHAREHOLDERS, INCLUDING US.

         THE INFORMATION CONTAINED ELSEWHERE IN THIS PROSPECTUS, AND IN OUR ANNUAL REPORT OR IN OUR OTHER FILINGS WITH THE SEC, INCLUDING UNDER THE CAPTION "RISK FACTORS", OR INCORPORATED HEREIN OR THEREIN, IDENTIFIES OTHER

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IMPORTANT FACTORS THAT COULD CAUSE DIFFERENCES FROM OUR FORWARD LOOKING STATEMENTS. OUR FILINGS WITH THE SEC ARE AVAILABLE ON THE SEC'S WEBSITE AT WWW.SEC.GOV.

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

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

STATEMENT CONCERNING LIMITED LIABILITY

         THE ARTICLES OF AMENDMENT AND RESTATEMENT ESTABLISHING SELECT INCOME REIT, DATED MARCH 9, 2012, AS AMENDED, AS FILED WITH STATE DEPARTMENT OF ASSESSMENTS AND TAXATION OF MARYLAND, PROVIDES THAT NO TRUSTEE, OFFICER, SHAREHOLDER, EMPLOYEE OR AGENT OF SELECT INCOME REIT SHALL BE HELD TO ANY PERSONAL LIABILITY, JOINTLY OR SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST, SELECT INCOME REIT. ALL PERSONS DEALING WITH SELECT INCOME REIT IN ANY WAY SHALL LOOK ONLY TO THE ASSETS OF SELECT INCOME REIT FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY OBLIGATION.

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