Exhibit 1.1

DIGITAL REALTY TRUST, INC.

20,000,000 Shares a/

Common Stock

($0.01 par value)

Underwriting Agreement

New York, New York

October 28, 2004

Citigroup Global Markets Inc.

Merrill Lynch, Pierce, Fenner & Smith Incorporated

As Representatives of the several Underwriters,

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

Ladies and Gentlemen:

Digital Realty Trust, Inc., a corporation organized under the laws of the State of Maryland (the “Company”), proposes to sell to the several underwriters named in Schedule I hereto (the “Underwriters”), for whom you (the “Representatives”) are acting as representatives, 20,000,000 shares of Common Stock, $0.01 par value (“Common Stock”) of the Company (said shares to be issued and sold by the Company being hereinafter called the “Underwritten Securities”). The Company also proposes to grant to the Underwriters an option to purchase up to 3,000,000 additional shares of Common Stock to cover over-allotments (the “Option Securities”; the Option Securities, together with the Underwritten Securities, being hereinafter called the “Securities”). To the extent there are no additional Underwriters listed on Schedule I other than you, the term Representatives as used herein shall mean you, as Underwriters, and the terms Representatives and Underwriters shall mean either the singular or plural as the context requires. Certain terms used herein are defined in Section 17 hereof.

The Company is the sole general partner of Digital Realty Trust, L.P., a Maryland limited partnership (the “Operating Partnership”), the Company’s operating partnership subsidiary. On or prior to the Closing Date (as hereafter defined), the Company will complete a series of transactions (the “Formation Transactions”) described in the Prospectus under the captions

a/ Plus an option to purchase from the Company, up to 3,000,000 additional Securities to cover over–allotments.

“Structure and Formation of Our Company” and “Certain Relationships and Related Transactions” pursuant to which certain persons will contribute their direct and indirect interests in certain properties, and interests in entities holding such properties (the “Property Partnerships”), to the Operating Partnership.

As part of the offering contemplated by this Agreement, Citigroup Global Markets Inc. has agreed to reserve out of the Securities set forth opposite its name on Schedule I to this Agreement, up to 93,805 shares (the “Directed Share Program”), for sale to the Company’s employees, officers, and directors and other parties associated with the Company or its subsidiaries (collectively, “Participants”). The Securities to be sold by Citigroup Global Markets Inc. pursuant to the Directed Share Program (the “Directed Shares”) will be sold by Citigroup Global Markets Inc. pursuant to this Agreement at the public offering price. Any Directed Shares not orally confirmed for purchase by any Participants by 8:00 A.M. New York City time on the business day following the date on which this Agreement is executed will be offered to the public by Citigroup Global Markets Inc. as set forth in the Prospectus.

1. Representations and Warranties. Each of the Company and the Operating Partnership, jointly and severally, represents and warrants to, and agrees with, each Underwriter as set forth below in this Section 1.

(a) The Company has prepared and filed with the Commission a registration statement (file number 333-117865) on Form S-11, including a related preliminary prospectus, for registration under the Act of the offering and sale of the Securities. The Company may have filed one or more amendments thereto, including a related preliminary prospectus, each of which has previously been furnished to you. The Company will next file with the Commission one of the following: either (1) prior to the Effective Date of such registration statement, a further amendment to such registration statement (including the form of final prospectus) or (2) after the Effective Date of such registration statement, a final prospectus in accordance with Rules 430A and 424(b). In the case of clause (2), the Company has included in such registration statement, as amended at the Effective Date, all information (other than Rule 430A Information) required by the Act and the rules thereunder to be included in such registration statement and the Prospectus. As filed, such amendment and form of final prospectus, or such final prospectus, shall contain all Rule 430A Information, together with all other such required information, and, except for such modifications to which the Representatives do not reasonably object, shall be in all substantive respects in the form furnished to you prior to the Execution Time or, to the extent not completed at the Execution Time, shall contain only such specific additional information and other substantive changes (beyond that contained in the latest Preliminary Prospectus) as the Company has advised you, prior to the Execution Time, will be included or made therein.

(b) On the Effective Date, the Registration Statement did or will, and when the Prospectus is first filed (if required) in accordance with Rule 424(b) and on the Closing Date (as defined herein) and on any date on which Option Securities are purchased, if such date is not the Closing Date (a “settlement date”), the Prospectus (and any supplements thereto) will, comply in all material respects with the applicable requirements of the Act and the rules thereunder; on the Effective Date and at the

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Execution Time, the Registration Statement did not or will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading; and, on the Effective Date, the Prospectus, if not filed pursuant to Rule 424(b), will not, and on the date of any filing pursuant to Rule 424(b) and on the Closing Date and any settlement date, the Prospectus (together with any supplement thereto) will not, include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, however, that the Company makes no representations or warranties as to the information contained in or omitted from the Registration Statement, or the Prospectus (or any supplement thereto) in reliance upon and in conformity with information furnished in writing to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion in the Registration Statement or the Prospectus (or any supplement thereto). No stop order suspending the effectiveness of the Registration Statement or any part thereof has been issued and no proceeding for that purpose has been instituted or threatened by the Commission or by the state securities authority of any jurisdiction. No order preventing or suspending the use of the Prospectus has been issued and no proceeding for that purpose has been instituted by the Commission or by the state securities authority of any jurisdiction.

(c) (i) The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of State of Maryland with full corporate power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Prospectus, and to enter into and perform its obligations under this Agreement and the Formation Transaction Documents (as hereafter defined) to which it is a party and as general partner of the Operating Partnership to cause the Operating Partnership to enter into and perform the Operating Partnership’s obligations under this Agreement and the Formation Transaction Documents to which the Operating Partnership is a party and is duly qualified to do business as a foreign corporation and is in good standing under the laws of each jurisdiction which requires such qualification except where the failure to be so qualified would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(ii) The Operating Partnership has been duly formed and is validly existing as a limited partnership in good standing under the laws of the State of Maryland with full power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Prospectus and to enter into and perform its obligations under this Agreement and the Formation Transaction Documents to which it is a party, and is duly qualified to do business and is in good standing as a foreign limited partnership under the laws of each jurisdiction which requires such qualification except where the failure to be so qualified would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business. At the Closing Date, the aggregate percentage interests of the Company and the limited partners

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in the Operating Partnership will be as set forth in the Prospectus; provided, that to the extent any portion of the over-allotment option described in Section 2(b) hereof is exercised at the Closing Date, the percentage interest of the Company and of such limited partners in the Operating Partnership will be adjusted accordingly.

(iii) Each subsidiary (as defined below) of the Company has been duly formed and is validly existing as a corporation, limited liability company or limited partnership, as the case may be, in good standing under the laws of the jurisdiction in which it is chartered or organized with full power and authority (corporate and other) to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Prospectus, and is duly qualified to do business as a foreign corporation, limited liability company or limited partnership, as the case may be, and is in good standing under the laws of each jurisdiction which requires such qualification except where the failure to be so qualified would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(d) All the outstanding shares of capital stock or other ownership interests of each subsidiary have been duly and validly authorized and issued and are fully paid and nonassessable, and, as of the Closing Date, except as otherwise set forth in the Prospectus, all outstanding shares of capital stock or other ownership interests of the subsidiaries will be owned by the Company either directly or through wholly owned subsidiaries free and clear of any perfected security interest or any other security interests, claims, mortgages, pledges, liens, encumbrances or other restrictions of any kind (collectively, “Liens”), except for Liens securing indebtedness as described in the Prospectus and except where such Liens would not individually or in the aggregate materially affect or interfere in any material respect with the Company’s ability to exercise control over each of such subsidiaries. Except as set forth in the Prospectus, there are no outstanding options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities or interests for capital stock or other ownership interests of any subsidiary.

(e) The Company’s authorized equity capitalization is as set forth in the Prospectus; the capital stock of the Company conforms in all material respects to the description thereof contained in the Prospectus; the outstanding shares of Common Stock have been duly and validly authorized and issued and are fully paid and nonassessable; the Securities have been duly and validly authorized, and, when issued and delivered to and paid for by the Underwriters pursuant to this Agreement, will be fully paid and nonassessable; the Securities are duly listed, and admitted and authorized for trading, subject to official notice of issuance and evidence of satisfactory distribution, on the New York Stock Exchange; the certificates for the Securities are in valid and sufficient form; the holders of outstanding shares of capital stock of the Company are not entitled to preemptive or other rights to subscribe for the Securities; and, except as set forth in the Prospectus, no options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities for, shares of capital stock of or ownership interests in the Company are outstanding; all

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offers and sales of the Company’s shares of Common Stock prior to the date hereof were at all relevant times duly registered under the Act or were exempt from the registration requirements of the Act and were duly registered or the subject of an available exemption from the registration requirements of the applicable state securities or blue sky laws.

(f) The units of limited partnership (“Units”) of the Operating Partnership issued or to be issued in connection with the Formation Transactions, including without limitation, the Units to be issued to the Company, have been duly authorized for issuance by the Operating Partnership to the holders or prospective holders thereof, and at the Closing Date will be validly issued and fully paid. The Units will be exempt from registration or qualification under the Act and applicable state securities laws. None of the Units will be issued in violation of the preemptive or other similar rights of any security holder of the Operating Partnership or any other person or entity. Except as set forth in the Prospectus, there are no outstanding options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities or interests for, Units or other ownership interests of the Operating Partnership.

(g) There is no franchise, contract or other document of a character required to be described in the Registration Statement or Prospectus, or to be filed as an exhibit thereto, which is not described or filed as required; and the statements in the Prospectus under the headings “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Material Provisions of Consolidated Indebtedness to be Outstanding After this Offering,” “Description of the Partnership Agreement of Digital Realty Trust, L.P.,” “Description of Securities,” “Material Provisions of Maryland Law and of Our Charter and Bylaws” and “Federal Income Tax Considerations,” insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are accurate and fair summaries of such legal matters, agreements, documents or proceedings.

(h) This Agreement and each of (i) the GI Partners contribution agreement, (ii) the eBay Data Center purchase agreement, (iii) the 200 Paul Avenue and 1100 Space Park Drive contribution agreement, (iv) the Univision Tower contribution agreement, (v) the amended and restated agreement of limited partnership of the Operating Partnership, (vi) the Carrier Center option agreement and (vii) the transition services agreement, in each case as identified in the Prospectus under the captions “Certain Relationships and Related Transactions” and/or “Structure and Formation of Our Company” (collectively, the “Formation Transaction Documents”) has been duly authorized, executed and delivered by the Company and the Operating Partnership to which it is a party; each Formation Transaction Document to which it is a party constitutes a legally valid and binding obligation of each of the Company and the Operating Partnership, enforceable against each of the Company and the Operating Partnership in accordance with its terms, except to the extent that such enforceability may be limited by applicable bankruptcy, insolvency, reorganization or other similar laws relating to or affecting creditors’ rights and general principles of equity and except as rights to indemnity and contribution thereunder may be limited by applicable law or policies underlying such law.

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(i) Each of the Company and the Operating Partnership is not and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Prospectus, will not be an “investment company” as defined in the Investment Company Act of 1940, as amended.

(j) No consent, approval, authorization, filing with or order of any court or governmental agency or body is required in connection with the transactions contemplated herein or by the Formation Transaction Documents, except such as have been obtained under the Act, such as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Securities by the Underwriters in the manner contemplated herein and in the Prospectus or such consents, approvals, authorizations, filings or orders that will be obtained or completed by the Closing Date or the absence of which, individually or in the aggregate, would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(k) Neither the issue and sale of the Securities nor the consummation of any other of the transactions herein contemplated or by the Formation Transaction Documents nor the fulfillment of the terms hereof or thereof will conflict with, result in a breach or violation of, or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, (i) the charter or by-laws of the Company or the organizational or other governing documents of any of its subsidiaries, (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its or their property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties, except, in the case of clauses (ii) or (iii) above, for such conflicts, breaches, violations, liens, charges or encumbrances that, individually or in the aggregate, would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(l) No holders of securities of the Company have rights to the registration of such securities under the Registration Statement. Except as set forth in the Prospectus, there are no contracts, agreements or understandings between the Company or the Operating Partnership and any person granting such person the right to require the Company or the Operating Partnership to file a registration statement under the Act with respect to any securities of the Company or the Operating Partnership owned or to be owned by such person or to require the Company or the Operating Partnership to include such securities in any securities being registered pursuant to any other registration statement filed by the Company or the Operating Partnership under the Act.

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(m) The consolidated historical financial statements and schedules of the Company and its consolidated subsidiaries included in the Prospectus and the Registration Statement present fairly in all material respects the financial condition, results of operations and cash flows of the Company as of the dates and for the periods indicated, comply as to form in all material respects with the applicable accounting requirements of the Act and have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved (except as otherwise noted therein). The selected financial data set forth under the caption “Selected Financial Data” in the Prospectus and Registration Statement fairly present in all material respects, on the basis stated in the Prospectus and the Registration Statement, the information included therein. The pro forma financial statements included in the Prospectus and the Registration Statement include assumptions that provide a reasonable basis for presenting the significant effects directly attributable to the transactions and events described therein, the related pro forma adjustments give appropriate effect to those assumptions, and the pro forma adjustments reflect the proper application of those adjustments to the historical financial statement amounts in the pro forma financial statements included in the Prospectus and the Registration Statement. The pro forma financial statements included in the Prospectus and the Registration Statement comply as to form in all material respects with the applicable accounting requirements of Regulation S-X under the Act and the pro forma adjustments have been properly applied to the historical amounts in the compilation of those statements.

(n) No action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries or its or their property is pending or, to the best knowledge of the Company, threatened that (i) could reasonably be expected to have a material adverse effect on the performance of this Agreement or the Formation Transaction Documents or the consummation of any of the transactions contemplated hereby or thereby or (ii) could reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(o) (i) Upon consummation of the Formation Transactions, except with respect to the Carrier Center property, which the Operating Partnership has an option to acquire and which option is expected to be exercised simultaneously with, or shortly after, the Closing Date, the Company or its subsidiaries will have fee simple title (or in the case of the ASM Lithography property, a leasehold interest, and in the case of the eBay Data Center property, a 75% tenancy in common interest) to all of the properties described in the Prospectus as owned or leased by them and the improvements (exclusive of improvements owned by tenants) located thereon (the “Properties”), in each case, free and clear of all liens, encumbrances, claims, security interests, restrictions and defects, except such as are set forth in the title reports and commitments listed on Schedule 1(o) hereto, are disclosed in the Prospectus or do not affect the value of such Property and do not interfere with the use made and proposed to be made of such Property by the Company and any subsidiary; (ii) except as otherwise set forth in or contemplated in the

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Prospectus, the mortgages and deeds of trust encumbering the Properties described in the Prospectus are not convertible into debt or equity securities of the Company or the Operating Partnership and such mortgages and deeds of trust are not cross-defaulted or cross-collateralized to any property not owned directly or indirectly by the Company or its subsidiaries; (iii) neither the Company nor any of its subsidiaries has received from any governmental authority any written notice of any condemnation of or zoning change affecting the Properties or any part thereof, and none of the Company or any subsidiary knows of any such condemnation or zoning change which is threatened and which if consummated would reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business; (iv) each of the Properties complies with all applicable codes, laws and regulations (including without limitation, building and zoning codes, laws and regulations and laws relating to access to the Properties), except if and to the extent disclosed in the Prospectus and except for such failures to comply that would not individually or in the aggregate reasonably be expected to materially affect the value of such Property or interfere in any material respect with the use made and proposed to be made of such Property by the Company or any subsidiary; (v) the Company or a subsidiary has obtained a title insurance policy on, or a so-called “fairway endorsement” on existing title policies (in states where such endorsement is available) covering, the fee interests (or leasehold interests in the case of the ASM Lithography property) from a title insurance company, or, if such title insurance policy has not yet been issued, a binding commitment by such title insurance company to issue such a policy, in any event covering each Property, with coverage in an amount at least equal to 80% of the cost of acquisition of such Property, including the principal amount of any indebtedness assumed with respect to the Property, provided that for any coverage less than 100% of such Property’s cost (including the principal amount of any indebtedness to be assumed with respect to the Property), such policy includes a so-called “tie-in endorsement” in states where such endorsement is available; (vi) true, correct and complete copies of the leases, exhibits, schedules or other documents that comprise the leases described in the “Business and Properties” section of the Prospectus where the tenant has been specifically identified (the “Major Leases”) have been provided to the Underwriters or their counsel; (vii) except as set forth in the Prospectus, neither the Company nor any subsidiary holds any Property under a ground lease; and (viii) to the knowledge of the Company and the Operating Partnership, except as set forth in or contemplated in the Prospectus, reflected in the pro forma financial statements or as disclosed in any tenant estoppel certificates, and, with respect to (A), (B) and (C) below, except as would not individually or in the aggregate reasonably be expected to materially affect the value of such Property or interfere in any material respect with the use made and proposed to be made of such Property by the Company or any subsidiary: (A) no rentals or other amounts due under the Major Leases have been paid more than one (1) month in advance; (B) no tenant has asserted in writing any defense or set-off against the payment of rent in connection with the Major Leases nor has any tenant contested any tax, operating cost or other escalation payment or occupancy charge, or any other amounts payable under its Major Leases; (C) all tenants, licensees, franchisees or other parties under the Major Leases are in possession of their respective premises; (D) none of the

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Major Leases has been assigned, mortgaged, pledged, sublet, hypothecated or otherwise encumbered, except for Liens securing indebtedness described in the Prospectus; (E) neither the Company nor the Operating Partnership has waived in writing any material provision under any Major Lease; (F) there are no uncured events of default, or events that with the giving of notice or passage of time, or both, would constitute an event of default, by any tenant under any of the terms and provisions of the Major Leases; and (G) no tenant under any of the leases at the Properties has a right of first refusal to purchase the premises demised under such lease.

(p) The Company and its subsidiaries own, possess, license or have other rights to use, on reasonable terms, all patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, trade secrets, technology, know-how and other intellectual property (collectively, the “Intellectual Property”) reasonably necessary for the conduct of the Company’s and the Operating Partnership’s business as now conducted or as proposed in the Prospectus to be conducted. Except as set forth in the Prospectus; (i) to the Company’s or the Operating Partnership’s best knowledge, there is no material infringement by third parties of any such Intellectual Property and (ii) there is no pending or, to the Company’s or the Operating Partnership’s best knowledge, threatened action, suit, proceeding or claim by others that the Company or the Operating Partnership infringes or otherwise violates any patent, trademark, copyright, trade secret or other proprietary rights of others, and the Company is unaware of any other fact which would form a reasonable basis for any such claim.

(q) Neither the Company nor any subsidiary is in violation or default of (i) any provision of its charter, bylaws or other organizational or governing documents, (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject, or (iii) any statute, law, rule, regulation, judgment, order or decree of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable, except, in the case of clauses (ii) or (iii) above, for such violations or defaults that, individually or in the aggregate, would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(r) KPMG LLP, who have certified the financial statements and supporting schedules included in the Prospectus and delivered their reports with respect to the audited financial statements and schedules included in the Prospectus, are independent public accountants within the meaning of the Act and the applicable published rules and regulations thereunder.

(s) The Company and each of its subsidiaries has filed all foreign, federal, state and local tax returns that are required to be filed or has requested extensions thereof (except in any case in which the failure so to file would not reasonably be expected to

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have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto) and has paid all taxes required to be paid by it and any other assessment, fine or penalty levied against it, to the extent that any of the foregoing is due and payable, except for any such tax, assessment, fine or penalty that is currently being contested in good faith or as would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(t) No material labor problem or dispute with the employees of the Company or any of its subsidiaries exists or is threatened or imminent.

(u) The Company and each of its subsidiaries are insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as are prudent and customary in the businesses in which they are engaged; all policies of insurance and fidelity or surety bonds insuring the Company or any of its subsidiaries or their respective businesses, assets, employees, officers and directors are in full force and effect; the Company and its subsidiaries are in compliance with the terms of such policies and instruments in all material respects; and there are no claims by the Company or any of its subsidiaries under any such policy or instrument as to which any insurance company is denying liability or defending under a reservation of rights clause; neither the Company nor any such subsidiary has been refused any insurance coverage sought or applied for; and neither the Company nor any such subsidiary has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(v) No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends or distributions to the Company, from making any other distribution on such subsidiary’s capital stock or equity interests, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except with respect to Global Stanford Place III, LLC or except pursuant to the terms of any indebtedness set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(w) The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by the appropriate federal, state or foreign regulatory authorities necessary to conduct their respective businesses, except for such licenses,

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certificates, permits and other authorizations the absence of which, individually or in the aggregate, would not reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business; and neither the Company nor any such subsidiary has received any notice of proceedings relating to the revocation or modification of any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(x) The Company and each of its subsidiaries maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

(y) The Company has not taken, directly or indirectly, any action designed to or that would constitute or that would reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(z) The Company and its subsidiaries are (i) in compliance with any and all applicable foreign, federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received and are in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses and (iii) have not received notice of any actual or potential liability under any Environmental Laws, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals, or liability would not, individually or in the aggregate, reasonably be expected to have a material adverse change in the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto). Except as set forth in the Prospectus, neither the Company nor any of the subsidiaries has been notified that it has been named as a “potentially responsible party” under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended. Except as otherwise set forth in the Prospectus, and except as would not individually or in the aggregate reasonably be expected to materially affect the value of such Property or interfere in any material respect with the

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use made and proposed to be made of such Property by the Company or any subsidiary, to the knowledge of the Company and the Operating Partnership, there have been no and are no (i) aboveground or underground storage tanks; (ii) polychlorinated biphenyls (“PCBs”) or PCB-containing equipment; (iii) asbestos or asbestos containing materials; (iv) lead based paints; (v) mold or other airborne contaminants; or (vi) dry-cleaning facilities in, on, under, or about any Property owned by the Company, the Operating Partnership or their subsidiaries.

(aa) In the ordinary course of its business, the Company periodically reviews the effect of Environmental Laws on the business, operations and properties of the Company and its subsidiaries, in the course of which it identifies and evaluates associated costs and liabilities (including, without limitation, any capital or operating expenditures required for clean-up, closure of properties or compliance with Environmental Laws, or any permit, license or approval, any related constraints on operating activities and any potential liabilities to third parties). On the basis of such review, the Company has reasonably concluded that such associated costs and liabilities would not, singly or in the aggregate, reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(bb) Neither the Company nor any of its subsidiaries maintains or contributes to any “pension plan” (within the meaning of Section 3(2) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”)) that is subject to Title IV of ERISA or any “multiemployer plan” (within the meaning of Section 4001(a)(3) of ERISA). Each “pension plan” (within the meaning of Section 3(2) of ERISA) maintained by the Company or any of its subsidiaries which is intended to be qualified under Section 401(a) of the Code has received a favorable determination or opinion letter from the Internal Revenue Service that such plan is so qualified. Neither the Company nor any of its subsidiaries maintains or is required to contribute to a “welfare plan” (as defined in Section 3(1) of ERISA) which provides retiree or other post-employment welfare benefits or insurance coverage (other than “continuation coverage” (as defined in Section 602 of ERISA) or as otherwise required by applicable law). Each “employee benefit plan” (within the meaning of Section 3(3) of ERISA) established or maintained by the Company and/or one or more of its subsidiaries is in compliance with the currently applicable provisions of ERISA except for such failures to comply that would not individually or in the aggregate reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(cc) There is and has been no failure on the part of the Company and any of the Company’s directors or officers, in their capacities as such, to comply with any applicable provision of the Sarbanes Oxley Act of 2002 and the rules and regulations promulgated in connection therewith (the “Sarbanes Oxley Act”) except for such failures to comply that would not individually or in the aggregate reasonably be expected to have

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a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(dd) Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (“FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA and the Company, its subsidiaries and, to the knowledge of the Company and the Operating Partnership, its affiliates have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith except for such violations or failures to comply that would not individually or in the aggregate reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(ee) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened except for such failures to comply, actions, suits or proceedings that would not individually or in the aggregate reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(ff) Except as would not individually or in the aggregate reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not directly

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or indirectly use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(gg) Except as set forth in the Prospectus, the Company and its subsidiaries have good and marketable title to all personal property owned by them, free and clear of all encumbrances and defects; and all personal property held under lease by the Company or any subsidiary are held by it under valid, subsisting and enforceable leases, in each case, with such exceptions as are not material and do not interfere with the use made and proposed to be made of such property by the Company or the subsidiary.

(hh) No relationship, direct or indirect, exists between or among the Company on the one hand, and the directors, officers, or shareholders of the Company on the other hand, which is required to be described in the Prospectus and which is not so described.

(ii) The statistical and market-related data included in the Prospectus and the Registration Statement are based on or derived from sources that the Company believes to be reliable and accurate.

(jj) Commencing with its taxable year ending December 31, 2004, the Company will be organized and operated in conformity with the requirements for qualification and taxation as a real estate investment trust (a “REIT”) under the Internal Revenue Code 1986, as amended (the “Code”), and its proposed method of operation will enable it to meet the requirements for qualification and taxation as a REIT under the Code. Each of the Company’s corporate subsidiaries qualifies as a “taxable REIT subsidiary” within the meaning of Section 856(l) of the Code and all applicable regulations under the Code.

(kk) The Company and Operating Partnership and each of their subsidiaries (including any predecessor entities) have not distributed, and prior to the later of the Closing Date and the completion of the distribution of the Underwritten Securities, will not distribute, any offering material in connection with the offering or sale of the Underwritten Securities other than the Registration Statement, the Prospectus or any other materials, if any, permitted by the Act.

(ll) Furthermore, the Company and the Operating Partnership represent and warrant to Citigroup Global Markets Inc. that (i) the Registration Statement, the Prospectus and any preliminary prospectus comply, and any further amendments or supplements thereto will comply, with any applicable laws or regulations of foreign jurisdictions in which the Prospectus or any preliminary prospectus, as amended or supplemented, if applicable, are distributed in connection with the Directed Share Program, and that (ii) no authorization, approval, consent, license, order, registration or qualification of or with any government, governmental instrumentality or court, other than such as have been obtained, is necessary under the securities laws and regulations of foreign jurisdictions in which the Directed Shares are offered outside the United States. The Company has not offered, or caused the Underwriters to offer, Securities to any

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person pursuant to the Directed Share Program with the specific intent to unlawfully influence (i) a tenant or vendor of the Company or the Operating Partnership to alter the tenant’s or vendor’s level or type of business with the Company or the Operating Partnership, or (ii) a trade journalist or publication to write or publish favorable information about the Company or its properties.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Underwriters in connection with the offering of the Securities pursuant to this Agreement shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

2. Purchase and Sale.

(a) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Company, at a purchase price of $11.25 per share, the amount of the Underwritten Securities set forth opposite such Underwriter’s name in Schedule I hereto.

(b) Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company hereby grants an option to the several Underwriters to purchase, severally and not jointly, up to 3,000,000 Option Securities at the same purchase price per share as the Underwriters shall pay for the Underwritten Securities. Said option may be exercised only to cover over-allotments in the sale of the Underwritten Securities by the Underwriters. Said option may be exercised in whole or in part at any time on or before the 30th day after the date of the Prospectus upon written or telegraphic notice by the Representatives to the Company setting forth the number of shares of the Option Securities as to which the several Underwriters are exercising the option and the settlement date. The number of Option Securities to be purchased by each Underwriter shall be the same percentage of the total number of shares of the Option Securities to be purchased by the several Underwriters as such Underwriter is purchasing of the Underwritten Securities, subject to such adjustments as you in your absolute discretion shall make to eliminate any fractional shares.

3. Delivery and Payment. Delivery of and payment for the Underwritten Securities and the Option Securities (if the option provided for in Section 2(b) hereof shall have been exercised on or before the third Business Day prior to the Closing Date) shall be made at 10:00 AM, New York City time, on November 3, 2004, or at such time on such later date not more than three Business Days after the foregoing date as the Representatives shall designate, which date and time may be postponed by agreement between the Representatives and the Company or as provided in Section 9 hereof (such date and time of delivery and payment for the Securities being herein called the “Closing Date”). Delivery of the Securities shall be made to the Representatives for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to an account specified by the Company. Delivery of the Underwritten Securities and the Option Securities shall be made through the facilities of The Depository Trust Company unless the Representatives shall otherwise instruct.

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If the option provided for in Section 2(b) hereof is exercised after the third Business Day prior to the Closing Date, the Company will deliver the Option Securities (at the expense of the Company) to the Representatives, at 388 Greenwich Street, New York, New York, on the date specified by the Representatives (which shall be within three Business Days after exercise of said option) for the respective accounts of the several Underwriters, against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to an account specified by the Company. If settlement for the Option Securities occurs after the Closing Date, the Company will deliver to the Representatives on the settlement date for the Option Securities, and the obligation of the Underwriters to purchase the Option Securities shall be conditioned upon receipt of, supplemental opinions, certificates and letters confirming as of such date the opinions, certificates and letters delivered on the Closing Date pursuant to Section 6 hereof.

4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Securities for sale to the public as set forth in the Prospectus.

5. Agreements. The Company agrees with the several Underwriters that:

(a) The Company will use its best efforts to cause the Registration Statement, if not effective at the Execution Time, and any amendment thereof, to become effective. Prior to the termination of the offering of the Securities, the Company will not file any amendment of the Registration Statement or supplement to the Prospectus or any Rule 462(b) Registration Statement unless the Company has furnished you a copy for your review prior to filing and will not file any such proposed amendment or supplement to which you reasonably object. Subject to the foregoing sentence, if the Registration Statement has become or becomes effective pursuant to Rule 430A, or filing of the Prospectus is otherwise required under Rule 424(b), the Company will cause the Prospectus, properly completed, and any supplement thereto to be filed in a form to which the Representatives do not reasonably object with the Commission pursuant to the applicable paragraph of Rule 424(b) within the time period prescribed and will provide evidence satisfactory to the Representatives of such timely filing. The Company will promptly advise the Representatives (1) when the Registration Statement, if not effective at the Execution Time, shall have become effective, (2) when the Prospectus, and any supplement thereto, shall have been filed (if required) with the Commission pursuant to Rule 424(b) or when any Rule 462(b) Registration Statement shall have been filed with the Commission, (3) when, prior to termination of the offering of the Securities, any amendment to the Registration Statement shall have been filed or become effective, (4) of any request by the Commission or its staff for any amendment of the Registration Statement, or any Rule 462(b) Registration Statement, or for any supplement to the Prospectus or for any additional information, (5) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or the institution or threatening of any proceeding for that purpose and (6) of the receipt by the Company of any notification with respect to the suspension of the qualification of the Securities for sale in any jurisdiction or the institution or threatening of any proceeding

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for such purpose. The Company will use its best efforts to prevent the issuance of any such stop order or the suspension of any such qualification and, if issued, to obtain as soon as possible the withdrawal thereof.

(b) If, at any time when a prospectus relating to the Securities is required to be delivered under the Act, any event occurs as a result of which the Prospectus as then supplemented would include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein in the light of the circumstances under which they were made not misleading, or if it shall be necessary to amend the Registration Statement or supplement the Prospectus to comply with the Act or the rules thereunder, the Company promptly will (1) notify the Representatives of any such event, (2) prepare and file with the Commission, subject to the second sentence of paragraph (a) of this Section 5, an amendment or supplement which will correct such statement or omission or effect such compliance; and (3) supply any supplemented Prospectus to you in such quantities as you may reasonably request.

(c) As soon as practicable, the Company will make generally available to its security holders and to the Representatives an earnings statement or statements of the Company and its subsidiaries which will satisfy the provisions of Section 11(a) of the Act and Rule 158 under the Act.

(d) The Company will furnish to the Representatives and counsel for the Underwriters signed copies of the Registration Statement (including exhibits thereto) and to each other Underwriter a copy of the Registration Statement (without exhibits thereto) and, so long as delivery of a prospectus by an Underwriter or dealer may be required by the Act, as many copies of each Preliminary Prospectus and the Prospectus and any supplement thereto as the Representatives may reasonably request.

(e) The Company will arrange, if necessary, for the qualification of the Securities for sale under the laws of such jurisdictions as the Representatives may designate and will maintain such qualifications in effect so long as required for the distribution of the Securities; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to service of process in suits, other than those arising out of the offering or sale of the Securities, in any jurisdiction where it is not now so subject.

(f) Except as set forth in the Prospectus, the Company will not, without the prior written consent of the Representatives, for a period of 180 days after the date of this Agreement, offer, sell, contract to sell, pledge, or otherwise dispose of, (or enter into any transaction which is designed to, or would reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company or any person controlled by the Company directly or indirectly, including the filing (or participation in the filing) of a registration statement (except for a registration statement on Form S-8 relating to the 2004 Incentive Award Plan or a registration statement on Form S-4 relating to an acquisition of a real property company) with the Commission in respect of, or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning

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of Section 16 of the Exchange Act, any other shares of Common Stock or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock, or publicly announce an intention to effect any such transaction, provided, however, that the Company may (i) grant stock options, restricted stock or long-term incentive units to employees, consultants or directors pursuant to the terms of a plan in effect at the Execution Time, (ii) issue Common Stock pursuant to: (A) the exercise of such options; (B) the redemption of Units issued upon conversion of such long-term incentive units; (C) the exercise of any employee stock options outstanding at the Execution Time; or (D) the redemption of Units issued upon conversion of long-term incentive units outstanding at the Execution Time, (iii) issue Common Stock pursuant to the Company’s dividend reinvestment plan (if any), and (iv) issue Common Stock or securities convertible into or exchangeable or exercisable for shares of Common Stock in connection with other acquisitions of real property or real property companies.

Notwithstanding the foregoing, if: (x) during the last 17 days of the 180-day lock-up period the Company issues an earnings release or material news or a material event relating to the Company occurs; or (y) prior to the expiration of the 180-day lock-up period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 180-day lock-up period, the restrictions described above shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

(g) Until and including the Closing Date or the settlement date for the Option Securities (whichever is later), the Company will comply with all applicable securities and other applicable laws, rules and regulations, including, without limitation, the Sarbanes Oxley Act, and will use its reasonable best efforts to cause the Company’s directors and officers, in their capacities as such, to comply with such laws, rules and regulations, including, without limitation, the provisions of the Sarbanes Oxley Act, except for such failures to comply that would not individually or in the aggregate reasonably be expected to have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business.

(h) The Company will not take, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, under the Exchange Act or otherwise, stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities.

(i) The Company agrees to pay the costs and expenses relating to the following matters: (i) the preparation, printing or reproduction and filing with the Commission of the Registration Statement (including financial statements and exhibits thereto), each Preliminary Prospectus, the Prospectus, and each amendment or supplement to any of them; (ii) the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Registration Statement, each Preliminary Prospectus, the Prospectus, and all amendments or supplements to any of them, as may, in each case, be reasonably requested for use in

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connection with the offering and sale of the Securities; (iii) the preparation, printing, authentication, issuance and delivery of certificates for the Securities, including any stamp or transfer taxes in connection with the original issuance and sale of the Securities; (iv) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Securities; (v) the registration of the Securities under the Exchange Act and the listing of the Securities on the New York Stock Exchange; (vi) any registration or qualification of the Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable fees and expenses of counsel for the Underwriters relating to such registration and qualification); (vii) any filings required to be made with the National Association of Securities Dealers, Inc. (“NASD”) (including filing fees and the reasonable fees and expenses of counsel for the Underwriters relating to such filings); (viii) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Securities; (ix) the fees and expenses of the Company’s accountants and the fees and expenses of counsel (including local and special counsel) for the Company; and (x) all other costs and expenses incident to the performance by the Company of its obligations hereunder.

(j) The Company and the Operating Partnership will use the net proceeds received by the Company from the sale of the Securities in the manner specified in the Prospectus under the caption “Use of Proceeds.”

(k) The Company will use its best efforts to meet the requirements to qualify, for the taxable year ending December 31, 2004, for taxation as a REIT under the Code.

(l) The Company agrees to pay (i) all fees and disbursements of counsel incurred by the Underwriters in connection with the Directed Share Program, (ii) all costs and expenses incurred by the Underwriters in connection with the printing (or reproduction) and delivery (including postage, air freight charges and charges for counting and packaging) of copies of the Directed Share Program material and (iii) all stamp duties, similar taxes or duties or other taxes, if any, incurred by the Underwriters in connection with the Directed Share Program.

Furthermore, the Company covenants with Citigroup Global Markets Inc. that the Company will comply with all applicable securities and other applicable laws, rules and regulations in each foreign jurisdiction in which the Directed Shares are offered in connection with the Directed Share Program.

6. Conditions to the Obligations of the Underwriters. The obligations of the Underwriters to purchase the Underwritten Securities and the Option Securities, as the case may be, shall be subject to the accuracy of the representations and warranties on the part of the Company contained herein as of the Execution Time, the Closing Date and any settlement date pursuant to Section 3 hereof, to the accuracy of the statements of the Company made in any certificates pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

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(a) If the Registration Statement has not become effective prior to the Execution Time, unless the Representatives agree in writing to a later time, the Registration Statement will become effective not later than (i) 6:00 PM New York City time on the date of determination of the public offering price, if such determination occurred at or prior to 3:00 PM New York City time on such date or (ii) 9:30 AM on the Business Day following the day on which the public offering price was determined, if such determination occurred after 3:00 PM New York City time on such date; if filing of the Prospectus, or any supplement thereto, is required pursuant to Rule 424(b), the Prospectus, and any such supplement, will be filed in the manner and within the time period required by Rule 424(b); and no stop order suspending the effectiveness of the Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or threatened.

(b) The Company shall have requested and caused Latham & Watkins LLP, counsel for the Company, to have furnished to the Representatives their opinion, dated the Closing Date and addressed to the Representatives, to the effect that:

(i) Based solely on certificates from public officials, such counsel confirms that the Company is qualified to do business in the States of California, Maryland, Colorado, Florida and Georgia;

(ii) Based solely on certificates from public officials, such counsel confirms that the Operating Partnership is qualified to do business in the States of California, Maryland, Colorado, Florida and Georgia;

(iii) Each Material Subsidiary (as defined therein) is a limited liability company or limited partnership, as the case may be, under the Corporations Code of the State of California, the Limited Liability Company Act of the State of Delaware or the Revised Uniform Limited Partnership Act of the State of Delaware, with the limited liability company or limited partnership power and authority to own its properties and to conduct its business as described in the Registration Statement and the Prospectus;

(iv) Based on certificates from public officials, such counsel confirms that each Material Subsidiary is validly existing and in good standing under the laws of the State of California or the State of Delaware, as the case may be, and is qualified to do business in the States listed on Schedule C thereto. With the consent of the Representatives based solely on an officer’s certificate, such counsel confirms that the Subsidiary Operating Agreement (as defined therein) of each Material Subsidiary is in full force and effect;

(v) No registration of the options to purchase shares of Common Stock or the long-term incentive units of the Operating Partnership (the “LTI Units”) under the Act or qualification thereof under the California Corporate Securities Law of 1968 is required for the issuance of the options or the LTI Units to certain executive officers and directors of the Company in the manner contemplated by the Employment Agreements listed on Schedule B thereto;

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(vi) No registration of the limited partnership units of the Operating Partnership (the “OP Units”) under the Act or qualification thereof under the California Corporate Securities Law of 1968 is required for the issuance of the OP Units in the manner contemplated by the Contribution Agreements listed on Schedule A thereto and the Option Agreement (as defined therein);

(vii) To the best of such counsel’s knowledge, there are no contracts or documents of a character required to be described in the Registration Statement or Prospectus or to be filed as exhibits to the Registration Statement that are not described or filed;

(viii) To the best of such counsel’s knowledge, there are no legal or governmental proceedings of a character required to be described in the Registration Statement or Prospectus that are not so described;

(ix) The statements in the Prospectus under the captions “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Material Provisions of Consolidated Indebtedness to be Outstanding After the Offering,” “Management—Employment Agreements,” “—Executive Chairman Agreement,” “Certain Relationships and Related Transactions—GI Partners Contribution Agreement,” “— eBay Data Center Purchase Agreement,” “—200 Paul Avenue and 1100 Space Park Drive Contribution Agreement,” “—Carrier Center Option and Right of First Offer Agreements,” “—Non-Competition Agreement with Global Innovation Partners, LLC,” “Shares Eligible for Future Sale,” and “ERISA Considerations,” insofar as they purport to describe or summarize certain provisions of the agreements, statutes or regulations referred to therein, are accurate descriptions or summaries in all material respects;

(x) The Registration Statement has become effective under the Act. With the consent of the Representatives, based solely on a telephonic confirmation by a member of the Staff of the Commission on November 3, 2004, no stop order suspending the effectiveness of the Registration Statement has been issued under the Act and no proceedings therefor have been initiated by the Commission. Any required filing of the Prospectus pursuant to Rule 424 under the Act has been made in accordance with Rule 424 under the Act;

(xi) The Registration Statement, as of the date it was declared effective, and the Prospectus, as of its date and as of the date hereof, appeared on their face to be appropriately responsive in all material respects to the requirements for registration statements on Form S-11 under the Act and the rules and regulations of the Commission thereunder; it being understood, however, that such counsel need express no opinion with respect to Regulation S-T or the financial statements, schedules, or other financial data, included in or omitted from, the Registration Statement or the Prospectus. For purposes of this paragraph, such counsel may assume that the statements made in the Registration Statement and the Prospectus are correct and complete;

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(xii) With the consent of the Representatives based solely on a certificate of an officer of the Company as to factual matters, each of the Company and the Operating Partnership is not, and immediately after giving effect to the sale of the Securities in accordance with this Agreement and the application of the proceeds as described in the Prospectus under the caption “Use of Proceeds,” will not be required to be registered as, an “investment company” within the meaning of the Investment Company Act of 1940, as amended;

(xiii) The execution and delivery of this Agreement by the Company and the Operating Partnership, the issuance and sale of the Securities by the Company to the Representatives and the other Underwriters pursuant to this Agreement, the execution and delivery by each of the Company and the Operating Partnership which is a party thereto of the Contribution Agreements, the eBay Purchase Agreement and the Option Agreement (each as defined therein) and the consummation by the Company and the Operating Partnership of the transactions contemplated by the Contribution Agreements, the eBay Purchase Agreement, and the Option Agreement, on the date hereof do not:

(A) violate the provisions of any Subsidiary Operating Agreement; or

(B) result in the breach of or a default under any of the Material Agreements (as defined therein); or

(C) violate any federal or California statute, rule or regulation applicable to the Company, the Operating Partnership or the Material Subsidiaries; or

(D) require any consents, approvals, or authorizations to be obtained by the Company, the Operating Partnership or any Material Subsidiary from, or any registrations, declarations or filings to be made by the Company, the Operating Partnership or any Material Subsidiary with, any governmental authority under any federal or California statute, rule or regulation applicable to the Company, the Operating Partnership or any Material Subsidiary, that have not been obtained or made;

(xiv) With the consent of the Representatives based solely on a certificate of an officer of the Company as to factual matters and a review of the Material Agreements, neither the Company nor the Operating Partnership nor any Material Subsidiary is a party to any agreement that would require the inclusion in the Registration Statement of shares or other securities owned by any person or entity other than the Company;

(xv) Each of the Contribution Agreements, the eBay Purchase Agreement and the Option Agreement is the legally valid and binding agreement of each of the Company and the Operating Partnership which is a party thereto, enforceable against each of them which is a party thereto in accordance with its terms; and

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(xvi) With the consent of the Representatives based solely on a written advice from the New York Stock Exchange, the Securities to be issued by the Company and sold pursuant to this Agreement have been listed, subject to official notice of issuance, on the New York Stock Exchange.

In rendering such opinion, such counsel may (A) assume the accuracy, as to matters involving the application of laws of any jurisdiction other than the State of California or the Federal laws of the United States, of the opinion of other counsel of good standing who are satisfactory to counsel for the Underwriters and (B) as to matters of fact, to the extent they deem proper, may rely on certificates of responsible officers of the Company and public officials. References to the Prospectus in this paragraph (b) shall also include any supplements thereto at the Closing Date.

In addition, such counsel shall separately state that:

No facts came to the attention of such counsel that caused them to believe that the Registration Statement, at the time it became effective, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading, or that the Prospectus, as of its date, or as of the date hereof, contained or contains an untrue statement of a material fact or omitted or omits to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; it being understood that such counsel need express no belief with respect to the financial statements, schedules, or other financial data included in, or omitted from, the Registration Statement or the Prospectus.

(c) The Company shall have requested and caused Latham & Watkins LLP, tax counsel for the Company, to have furnished to the Representatives their opinion, dated the Closing Date and addressed to the Representatives, to the effect that:

(i) the statements included in the Prospectus under the headings “Federal Income Tax Considerations” and “Restrictions on Ownership of our Stock,” insofar as such statements purport to summarize certain provisions of the agreements, statutes and regulations referred to therein, are accurate summaries in all material respects; and

(ii) commencing with its taxable year ending December 31, 2004, the Company will be organized in conformity with the requirements for qualification as a real estate investment trust (a “REIT”) under the Internal Revenue Code of 1986, as amended (the “Code”), and its proposed method of operation will enable it to meet the requirements for qualification and taxation as a REIT under the Code.

In rendering such opinion, such counsel may rely (A) as to matters involving the application of laws of any jurisdiction other than the State of California or the

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Federal laws of the United States, to the extent they deem proper and specified in such opinion, upon the opinion of other counsel of good standing whom they believe to be reliable and who are satisfactory to counsel for the Underwriters and (B) as to matters of fact, to the extent they deem proper, on certificates of responsible officers of the Company and public officials. References to the Prospectus in this paragraph (c) shall also include any supplements thereto at the Closing Date.

(d) The Company shall have requested and caused Venable LLP, Maryland counsel for the Company, to have furnished to the Representatives their opinion, dated the Closing Date and addressed to the Representatives, to the effect that:

(i) the Company is a corporation duly incorporated and existing under and by virtue of the laws of the State of Maryland and is in good standing with the State Department of Assessments and Taxation of Maryland, with full corporate power to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Prospectus under the caption “Business and Properties”;

(ii) the Operating Partnership is a limited partnership duly formed and existing under and by virtue of the laws of the State of Maryland and is in good standing with the State Department of Assessments and Taxation of Maryland, with full limited partnership power to own or lease, as the case may be, and to operate its properties and to conduct its business as described in the Prospectus under the caption “Business and Properties”. The Company is the sole general partner of the Operating Partnership and the aggregate percentage interests of the Company and the limited partners in the Operating Partnership are as set forth in the Prospectus under the caption “Structure and Formation of Our Company”;

(iii) the Company’s authorized equity capitalization is as set forth in the Prospectus under the caption “Capitalization”; the stock of the Company conforms in all material respects to the description thereof contained in the Prospectus under the caption “Description of Securities”; the issuance of the outstanding shares of Common Stock has been duly authorized and such shares are validly issued, fully paid and nonassessable; the issuance of the Securities has been duly authorized and, when issued and delivered to and paid for by the Underwriters pursuant to this Agreement, the Securities will be validly issued, fully paid and nonassessable; the certificates for the Securities comply in all material respects with the Maryland General Corporation Law; the holders of outstanding shares of stock of the Company are not entitled to preemptive or other rights to subscribe for the Securities arising under the Maryland General Corporation Law or the charter or bylaws of the Company; and, based solely on a certificate executed by an officer of the Company and upon any facts otherwise known to such counsel, and except as set forth in the Prospectus, no options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities for shares of stock of or ownership interests in the Company are outstanding;

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(iv) the issuance of the Units issued in connection with the Formation Transactions, including, without limitation, the Units to be issued to the Company, has been duly authorized and such Units are validly issued, fully paid and nonassessable; the holders of outstanding Units are not entitled to preemptive or other rights to subscribe for the Securities arising under the Maryland Revised Uniform Limited Partnership Act or the Operating Partnership Agreement; based solely on a certificate executed by an officer of the Company and upon any facts otherwise known to such counsel, and except as set forth in the Prospectus, no options, warrants or other rights to purchase, agreements or other obligations to issue, or rights to convert any obligations into or exchange any securities for Units or ownership interests in the Operating Partnership are outstanding; the terms of the Units conform in all material respects to the description thereof contained in the Prospectus under the caption “Description of the Partnership Agreement of Digital Realty Trust, L.P.”;

(v) the statements included in the Prospectus under the headings “Risk Factors—Risks Related to Our Organizational Structure—Conflicts of interest exist or could arise in the future with holders of units in our operating partnership,” “Risk Factors—Risks Related to Our Organizational Structure—Our charter and Maryland law contain provisions that may delay, defer or prevent a change of control transaction,” “Risk Factors—Risks Related to Our Organizational Structure—Our rights and the rights of our stockholders to take action against our directors and officers are limited,” “Policies with Respect to Certain Activities—Interested Director and Officer Transactions,” “Description of the Partnership Agreement of Digital Realty Trust, L.P.,” “Description of Securities” and “Material Provisions of Maryland Law and of Our Charter and Bylaws,” insofar as such statements purport to summarize or describe matters of or legal conclusions relating to Maryland law, the charter or bylaws of the Company, or the Operating Partnership Agreement, are accurate and fair summaries of such matters, legal conclusions, the charter or bylaws of the Company, or the Operating Partnership Agreement in all material respects;

(vi) this Agreement and each of the Formation Transaction Documents to which the Company or the Operating Partnership is a party have been duly authorized, executed and delivered by the Company and the Operating Partnership; the Operating Partnership Agreement constitutes the legal, valid and binding obligation of each of the Company and the Operating Partnership, enforceable against each of the Company and the Operating Partnership in accordance with its terms;

(vii) no consent, approval or authorization of, filing with or order of any court or governmental agency or body in the State of Maryland is required in connection with the transactions contemplated herein or the transactions contemplated by the Formation Transaction Documents, except such as have been obtained or made; and

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(viii) neither the issuance and sale of the Securities, nor the consummation of any other transactions herein contemplated, nor the consummation of the transactions contemplated by the Formation Transaction Documents, nor the fulfillment of the terms hereof or thereof, will conflict with or result in a breach or violation of (A) the charter or bylaws of the Company or the Operating Partnership Agreement or (B) any Maryland statute or law or any rule, regulation, judgment, order or decree applicable to the Company or the Operating Partnership of any court, regulatory body, administrative agency, governmental body, or other authority of the State of Maryland having jurisdiction over the Company or the Operating Partnership or any of their properties.

In rendering such opinion, such counsel may rely (A) as to matters involving the application of laws of any jurisdiction other than the State of Maryland, to the extent they deem proper and specified in such opinion, upon the opinion of other counsel of good standing whom they believe to be reliable and who are satisfactory to counsel for the Underwriters and (B) as to matters of fact, to the extent they deem proper, on certificates of responsible officers of the Company and public officials. References to the Prospectus in this paragraph (d) shall also include any supplements thereto at the Closing Date.

(e) The Company shall have requested and caused Gibson, Dunn & Crutcher LLP, counsel to Global Innovation Partners, LLC (the “Contributor”), to have furnished to the Representatives their opinion, dated the Closing Date and addressed to the Representatives, to the effect that:

(i) The Transaction Documents (as defined therein) have been duly executed and delivered by the Contributor and are the legal, valid and binding obligations of the Contributor, enforceable against the Contributor in accordance with their terms.

In rendering such opinion, such counsel may rely (A) as to matters involving the application of laws of any jurisdiction other than the State of Delaware or the Federal laws of the United States, to the extent they deem proper and specified in such opinion, upon the opinion of other counsel of good standing whom they believe to be reliable and who are satisfactory to counsel for the Underwriters and (B) as to matters of fact, to the extent they deem proper, on certificates of responsible officers of the Company and public officials. References to the Prospectus in this paragraph (e) shall also include any supplements thereto at the Closing Date.

(f) The Company shall have requested and caused Richards, Layton & Finger, P.A., Delaware counsel to the Contributor, to have furnished to the Representatives their opinion, dated the Closing Date and addressed to the Representatives, to the effect that:

(i) The Contributor is validly existing in good standing as a limited liability company under the laws of the State of Delaware;

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(ii) Under the Delaware Limited Liability Company Act, 6 Del. C. § 18-101, et seq. (the “LLC Act”), and the LLC Agreement (as defined therein), the Contributor has all necessary limited liability company power and authority to execute and deliver the Transaction Documents (as defined therein), and to perform its obligations thereunder;

(iii) Under the LLC Act and the LLC Agreement, the execution and delivery by the Contributor of the Transaction Documents, and the performance by the Contributor of its obligations thereunder, have been duly authorized by all necessary limited liability company action on the part of the Company, including by all approvals of the members required under the LLC Agreement; and

(iv) The execution and delivery by the Contributor of the Transaction Documents, and the performance by the Contributor of its obligations thereunder, do not violate (i) any Delaware law, rule or regulation, or (ii) the LLC Certificate or the LLC Agreement.

In rendering such opinion, such counsel may rely (A) as to matters involving the application of laws of any jurisdiction other than the State of Delaware, to the extent they deem proper and specified in such opinion, upon the opinion of other counsel of good standing whom they believe to be reliable and who are satisfactory to counsel for the Underwriters and (B) as to matters of fact, to the extent they deem proper, on certificates of responsible officers of the Contributor and public officials. References to the Prospectus in this paragraph (f) shall also include any supplements thereto at the Closing Date.

(g) The Representatives shall have received from Goodwin Procter LLP, counsel for the Underwriters, such opinion or opinions, dated the Closing Date and addressed to the Representatives, with respect to the issuance and sale of the Securities, the Registration Statement, the Prospectus (together with any supplement thereto) and other related matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they reasonably request for the purpose of enabling them to pass upon such matters.

(h) The Company shall have furnished to the Representatives a certificate of the Company, signed by the Executive Chairman of the Board or the President and the principal financial or accounting officer of the Company, dated the Closing Date, to the effect that the signers of such certificate have carefully examined the Registration Statement, the Prospectus, any supplements to the Prospectus and this Agreement and that:

(i) the representations and warranties of the Company and the Operating Partnership in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date and the Company and the Operating Partnership have complied with all the agreements and satisfied all the conditions on their part to be performed or satisfied at or prior to the Closing Date;

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(ii) the Registration Statement has become effective under the Act and no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose have been instituted or, to the Company’s knowledge, threatened; and

(iii) since the date of the most recent financial statements included in the Prospectus (exclusive of any supplement thereto), there has been no material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto).

(i) The Company shall have requested and caused KPMG LLP to have furnished to the Representatives, at the Execution Time and at the Closing Date, letters, dated respectively as of the Execution Time and as of the Closing Date, in form and substance reasonably satisfactory to the Representatives, confirming that they are independent accountants within the meaning of the Act and the applicable rules and regulations adopted by the Commission thereunder and that they have performed a review of the unaudited interim financial information of the Company for the six-month period ended June 30, 2004, and as at June 30, 2004 in accordance with Statement on Auditing Standards No. 100 and stating in effect that:

(i) in their opinion the audited financial statements and financial statement schedules included in the Registration Statement and the Prospectus and reported on by them comply as to form in all material respects with the applicable accounting requirements of the Act and the related rules and regulations adopted by the Commission;

(ii) on the basis of a reading of the latest unaudited financial statements made available by the Company and its subsidiaries; their limited review, in accordance with standards established under Statement on Auditing Standards No. 100, of the unaudited interim financial information for the six-month period ended June 30, 2004, and as at June 30, 2004; carrying out certain specified procedures (but not an examination in accordance with generally accepted auditing standards) which would not necessarily reveal matters of significance with respect to the comments set forth in such letter; a reading of the minutes of the meetings of the stockholders, directors and board committees of the Company and the subsidiaries; and inquiries of certain officials of the Company who have responsibility for financial and accounting matters of the Company and its subsidiaries as to transactions and events subsequent to June 30, 2004, nothing came to their attention which caused them to believe that:

(1) any unaudited financial statements included in the Registration Statement and the Prospectus do not comply as to form in all material respects with applicable accounting requirements of the Act and with the related rules and regulations adopted by the Commission with

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respect to registration statements on Form S-11; and said unaudited financial statements are not in conformity with generally accepted accounting principles applied on a basis substantially consistent with that of the audited financial statements included in the Registration Statement and the Prospectus;

(2) with respect to the period subsequent to June 30, 2004 there were any changes, at a specified date not more than five days prior to the date of the letter, in the long-term debt of the Company and its subsidiaries or capital stock of the Company or decreases in the stockholders’ equity of the Company as compared with the amounts shown on the June 30, 2004 consolidated balance sheet included in the Registration Statement and the Prospectus, or for the period from July 1, 2004 to such specified date there were any decreases, as compared with the amounts shown on the statement of operations for the corresponding period in the previous year, in revenues or in total net income of the Company and its subsidiaries, except in all instances for changes or decreases set forth in such letter, in which case the letter shall be accompanied by an explanation by the Company as to the significance thereof unless said explanation is not deemed necessary by the Representatives; and

(3) the information included in the Registration Statement and Prospectus in response to Regulation S-K, Item 301 (Selected Financial Data) and Item 402 (Executive Compensation) is not in conformity with the applicable disclosure requirements of Regulation S-K;

(iii) they have performed certain other specified procedures as a result of which they determined that certain information of an accounting, financial or statistical nature (which is limited to accounting, financial or statistical information derived from the general accounting records of the Company and its subsidiaries) set forth in the Registration Statement and the Prospectus agrees with the accounting records of the Company and its subsidiaries, excluding any questions of legal interpretation; and

(iv) on the basis of a reading of the unaudited pro forma financial statements included in the Registration Statement and the Prospectus (the “pro forma financial statements”); carrying out certain specified procedures; inquiries of certain officials of the Company who have responsibility for financial and accounting matters; and proving the arithmetic accuracy of the application of the pro forma adjustments to the historical amounts in the pro forma financial statements, nothing came to their attention which caused them to believe that the pro forma financial statements do not comply as to form in all material respects with the applicable accounting requirements of Rule 11-02 of Regulation S-X or that the pro forma adjustments have not been properly applied to the historical amounts in the compilation of such statements.

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References to the Prospectus in this paragraph (h) include any supplement thereto at the date of the letter.

(j) Subsequent to the Execution Time or, if earlier, the dates as of which information is given in the Registration Statement (exclusive of any amendment thereof) and the Prospectus (exclusive of any supplement thereto), there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (h) of this Section 6 or (ii) any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Prospectus (exclusive of any supplement thereto) the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Registration Statement (exclusive of any amendment thereof) and the Prospectus (exclusive of any supplement thereto).

(k) Prior to the Closing Date, the Company shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

(l) Subsequent to the Execution Time, there shall not have been any decrease in the rating of any of the Company’s debt securities by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g) under the Act) or any notice given of any intended or potential decrease in any such rating or of a possible change in any such rating that does not indicate the direction of the possible change.

(m) The Securities shall have been listed and admitted and authorized for trading on the New York Stock Exchange, and satisfactory evidence of such actions shall have been provided to the Representatives.

(n) The NASD, upon review of the terms of the public offering of the Securities, shall not have objected to such offering, such terms or the Underwriters’ participation in same.

(o) The Company shall have furnished to the Representatives a letter in the form of Exhibit A hereto from each director and executive officer of the Company named in the Registration Statement and the Prospectus.

(p) An ALTA Owner’s Extended Coverage Policy or, in the case of any Property to be owned after the Closing by the same titleholding entity listed on an existing title policy, a so-called “fairway endorsement” on such existing title policy shall have been issued to the Company or a subsidiary for each of the Properties with coverage in an amount at least equal to 80% of the cost of acquisition of such Property in states where such endorsement is available.

(q) Commonwealth Land Title Insurance Company shall have issued its UCC 9 Insurance Policy or the equivalent for each of the Property Partnerships.

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(r) The Formation Transactions shall have been, or will be concurrently, consummated.

(s) The Credit Facility and other refinancing transactions shall have been, or will be concurrently, consummated.

If any of the conditions specified in this Section 6 shall not have been fulfilled when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be reasonably satisfactory in form and substance to the Representatives and counsel for the Underwriters, this Agreement and all obligations of the Underwriters hereunder may be canceled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing or by telephone or facsimile confirmed in writing.

The documents required to be delivered by this Section 6 shall be delivered at the office of Latham & Watkins LLP, counsel for the Company, at 633 West 5 th Street, Suite 4000, Los Angeles, California 90071, on the Closing Date.

7. Reimbursement of Underwriters’ Expenses. If the sale of the Securities provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied, because of any termination pursuant to Section 10 hereof or because of any refusal, inability or failure on the part of the Company or the Operating Partnership to perform any agreement herein or comply with any provision hereof other than by reason of a default by any of the Underwriters, the Company will reimburse the Underwriters severally through Citigroup Global Markets Inc. on demand for all out-of-pocket expenses (including reasonable fees and disbursements of counsel) that shall have been incurred by them in connection with the proposed purchase and sale of the Securities.

8. Indemnification and Contribution.

(a) The Company and the Operating Partnership, jointly and severally, agree to indemnify and hold harmless each Underwriter, the directors, officers, employees and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the registration statement for the registration of the Securities as originally filed or in any amendment thereof, or in any Preliminary Prospectus or the Prospectus, or in any amendment thereof or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company and the Operating Partnership will not be liable in any such case to the extent

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that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made therein in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion therein. This indemnity agreement will be in addition to any liability which the Company and the Operating Partnership may otherwise have.

(b) Each Underwriter severally and not jointly agrees to indemnify and hold harmless the Company and the Operating Partnership, each of the Company’s directors, each of the Company’s officers who signs the Registration Statement, and each person who controls the Company and the Operating Partnership within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company and the Operating Partnership to each Underwriter, but only with reference to written information relating to such Underwriter furnished to the Company by or on behalf of such Underwriter through the Representatives specifically for inclusion in the documents referred to in the foregoing indemnity. This indemnity agreement will be in addition to any liability which any Underwriter may otherwise have. The Company and the Operating Partnership acknowledge that the statements set forth in (i) the penultimate paragraph of the cover page regarding delivery of the Securities, (ii) the list of Underwriters and their respective participation in the sale of the Securities under the caption “Underwriting”, (iii) the sentences related to concessions and reallowances under the caption “Underwriting”, (iv) the three bullet-points in the eighth paragraph under the caption “Underwriting” related to stabilization, syndicate covering transactions and penalty bids, (v) the ninth paragraph under the caption “Underwriting” relating to penalty bids and (vi) the last paragraph under the caption “Underwriting” relating to online distribution in any Preliminary Prospectus and the Prospectus constitute the only information furnished in writing by or on behalf of the several Underwriters for inclusion in any Preliminary Prospectus or the Prospectus.

(c) The Company and the Operating Partnership agree to indemnify and hold harmless Citigroup Global Markets Inc., the directors, officers, employees and agents of Citigroup Global Markets Inc. and each person, who controls Citigroup Global Markets Inc. within the meaning of either the Act or the Exchange Act (“Citigroup Entities”), from and against any and all losses, claims, damages and liabilities to which they may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise (including, without limitation, any legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim), insofar as such losses, claims damages or liabilities (or actions in respect thereof) (i) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the prospectus wrapper material prepared by or with the consent of the Company for distribution in foreign jurisdictions in connection with the Directed Share Program attached to the Prospectus or any preliminary prospectus, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statement therein, when considered in conjunction with the Prospectus or any applicable preliminary prospectus, not misleading; (ii) caused by the failure of any Participant to pay for and accept delivery of the securities which immediately following the Effective Date

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of the Registration Statement, were subject to a properly confirmed agreement to purchase; or (iii) related to, arising out of, or in connection with the Directed Share Program, except that this clause (iii) shall not apply to the extent that such loss, claim, damage or liability is finally judicially determined to have resulted primarily from the gross negligence or willful misconduct of the Citigroup Entities.

(d) Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 8, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve it from liability under paragraph (a), (b) or (c) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a), (b) or (c) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest, (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party, (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party. Notwithstanding the foregoing, it is understood that the Company and the Operating Partnership shall, in connection with any action or related actions in the same jurisdiction, bear the fees, costs and expenses of only one such separate counsel (in addition to any local counsel) for all the Underwriters, the directors, officers, employees and agents of the Underwriters and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act (collectively, the “Underwriter Indemnified Parties”), provided, however, the Company and the Operating Partnership shall bear the fees, costs and expenses of more than one separate counsel (in addition to any local counsel) if the use of only one separate counsel for all the Underwriter Indemnified Parties would present such counsel with a conflict of interest with respect to one or more of the Underwriter Indemnified Parties. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending

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or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent (A) includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding and (B) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party. Notwithstanding anything contained herein to the contrary, if indemnity may be sought pursuant to paragraph (c) of this Section 8 in respect of such action or proceeding, then in addition to such separate firm for the indemnified parties, the indemnifying party shall be liable for the reasonable fees and expenses of not more than one separate firm (in addition to any local counsel) for Citigroup Global Markets Inc., the directors, officers, employees and agents of Citigroup Global Markets Inc., and all persons, if any, who control Citigroup Global Markets Inc. within the meaning of either the Act or the Exchange Act for the defense of any losses, claims, damages and liabilities arising out of the Directed Share Program.

(e) In the event that the indemnity provided in paragraph (a), (b) or (c) of this Section 8 is unavailable to or insufficient to hold harmless an indemnified party for any reason, the Company, the Operating Partnership and the Underwriters severally agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively “Losses”) to which the Company, the Operating Partnership and one or more of the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and by the Underwriters on the other from the offering of the Securities; provided, however, that in no case shall any Underwriter (except as may be provided in any agreement among underwriters relating to the offering of the Securities) be responsible for any amount in excess of the underwriting discount or commission applicable to the Securities purchased by such Underwriter hereunder. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company, the Operating Partnership and the Underwriters severally shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company and the Operating Partnership on the one hand and of the Underwriters on the other in connection with the statements or omissions which resulted in such Losses as well as any other relevant equitable considerations. Benefits received by the Company and the Operating Partnership shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Underwriters shall be deemed to be equal to the total underwriting discounts and commissions, in each case as set forth on the cover page of the Prospectus. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company or by the Operating Partnership on the one hand or the Underwriters on the other, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The Company, the Operating Partnership and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable

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considerations referred to above. Notwithstanding the provisions of this paragraph (e), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 8, each person who controls an Underwriter within the meaning of either the Act or the Exchange Act and each director, officer, employee and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls the Company or the Operating Partnership within the meaning of either the Act or the Exchange Act, each officer of the Company who shall have signed the Registration Statement and each director of the Company shall have the same rights to contribution as the Company and the Operating Partnership, subject in each case to the applicable terms and conditions of this paragraph (e).

9. Default by an Underwriter. If any one or more Underwriters shall fail to purchase and pay for any of the Securities agreed to be purchased by such Underwriter or Underwriters hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Underwriters shall be obligated severally to take up and pay for (in the respective proportions which the amount of Securities set forth opposite their names in Schedule I hereto bears to the aggregate amount of Securities set forth opposite the names of all the remaining Underwriters) the Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase; provided, however, that in the event that the aggregate amount of Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase shall exceed 10% of the aggregate amount of Securities set forth in Schedule I hereto, the remaining Underwriters shall have the right to purchase all, but shall not be under any obligation to purchase any, of the Securities, and if such nondefaulting Underwriters do not purchase all the Securities, this Agreement will terminate without liability to any nondefaulting Underwriter, the Company or the Operating Partnership. In the event of a default by any Underwriter as set forth in this Section 9, the Closing Date shall be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order that the required changes in the Registration Statement and the Prospectus or in any other documents or arrangements may be effected. Nothing contained in this Agreement shall relieve any defaulting Underwriter of its liability, if any, to the Company and any nondefaulting Underwriter for damages occasioned by its default hereunder.

10. Termination. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Securities, if at any time prior to such time (i) trading in the Company’s Common Stock shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such Exchange, (ii) a banking moratorium shall have been declared either by Federal or New York State authorities or (iii) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war, or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impractical or inadvisable to proceed with the offering or delivery of the Securities as contemplated by the Prospectus (exclusive of any supplement thereto).

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11. Representations and Indemnities to Survive. The respective agreements, representations, warranties, indemnities and other statements of the Company, the Operating Partnership or the officers of the Company and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of any Underwriter or the Company, the Operating Partnership or any of the officers, directors, employees, agents or controlling persons referred to in Section 8 hereof, and will survive delivery of and payment for the Securities. The provisions of Sections 7 and 8 hereof shall survive the termination or cancellation of this Agreement.

12. Notices. All communications hereunder will be in writing and effective only on receipt, and, if sent to the Representatives, will be mailed, delivered or telefaxed to the Citigroup Global Markets Inc. General Counsel (fax no.: (212) 816-7912) and confirmed to the General Counsel, Citigroup Global Markets Inc., at 388 Greenwich Street, New York, New York, 10013, Attention: General Counsel, and to Merrill Lynch, Pierce, Fenner & Smith Incorporated, 4 World Financial Center, New York, New York 10080, Attention: General Counsel, with a copy to Goodwin Procter LLP, attention Ettore A. Santucci (fax no.: (617) 523-1231) and confirmed to it at Goodwin Procter LLP, 53 State Street, Boston, Massachusetts, 02109, Attention: Ettore A. Santucci; or, if sent to the Company or the Operating Partnership, will be mailed, delivered or telefaxed to Digital Realty Trust, Inc. (fax no.: (650) 233-3601) and confirmed to it at Digital Realty Trust, Inc., 2370 Sand Hill Road, Suite 280, Menlo Park, California 94025, Attention: Michael F. Foust, with a copy to Latham & Watkins LLP, attention Julian T.H. Kleindorfer (fax no.: (213) 891-8763) and confirmed to it at Latham & Watkins LLP, 633 West 5 th Street, Suite 4000, Los Angeles, California 90071, Attention: Julian T.H. Kleindorfer.

13. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers, directors, employees, agents and controlling persons referred to in Section 8 hereof, and no other person will have any right or obligation hereunder.

14. Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

15. Counterparts. This Agreement may be signed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same agreement.

16. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

17. Definitions. The terms which follow, when used in this Agreement, shall have the meanings indicated.

“Act” shall mean the Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

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“Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in New York City.

“Commission” shall mean the Securities and Exchange Commission.

“Effective Date” shall mean each date and time that the Registration Statement, any post-effective amendment or amendments thereto and any Rule 462(b) Registration Statement became or become effective.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Execution Time” shall mean the date and time that this Agreement is executed and delivered by the parties hereto.

“Preliminary Prospectus” shall mean any preliminary prospectus referred to in Section 1(a) above and any preliminary prospectus included in the Registration Statement at the Effective Date that omits Rule 430A Information.

“Prospectus” shall mean the prospectus relating to the Securities that is first filed pursuant to Rule 424(b) after the Execution Time or, if no filing pursuant to Rule 424(b) is required, shall mean the form of final prospectus relating to the Securities included in the Registration Statement at the Effective Date.

“Registration Statement” shall mean the registration statement referred to in Section 1(a) above, including exhibits and financial statements, as amended at the Execution Time (or, if not effective at the Execution Time, in the form in which it shall become effective) and, in the event any post-effective amendment thereto or any Rule 462(b) Registration Statement becomes effective prior to the Closing Date, shall also mean such registration statement as so amended or such Rule 462(b) Registration Statement, as the case may be. Such term shall include any Rule 430A Information deemed to be included therein at the Effective Date as provided by Rule 430A.

“Rule 424”, “Rule 430A” and “Rule 462” refer to such rules under the Act.

“Rule 430A Information” shall mean information with respect to the Securities and the offering thereof permitted to be omitted from the Registration Statement when it becomes effective pursuant to Rule 430A.

“Rule 462(b) Registration Statement” shall mean a registration statement and any amendments thereto filed pursuant to Rule 462(b) relating to the offering covered by the registration statement referred to in Section 1(a) hereof.

“subsidiary” shall mean each direct and indirect subsidiary of the Company, including, without limitation, the Operating Partnership and the Property Partnerships contributed to Operating Partnership pursuant to the Formation Transactions.

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company, the Operating Partnership and the several Underwriters.

Very truly yours,
DIGITAL REALTY TRUST, INC.
By: |  | /s/ Michael F. Foust
Name: |  | Michael F. Foust
Title: |  | Chief Executive Officer
DIGITAL REALTY TRUST, L.P.
By: |  | Digital Realty Trust, Inc., its General Partner
By: |  | /s/ Michael F. Foust
Name: |  | Michael F. Foust
Title: |  | Chief Executive Officer

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The foregoing Agreement is hereby

confirmed and accepted as of the

date first above written.

CITIGROUP GLOBAL MARKETS INC.
MERRILL LYNCH, PIERCE, FENNER & SMITH
INCORPORATED
By: |  | Citigroup Global Markets Inc.
By: |  | /s/ John Todd
Name: |  | John Todd
Title: |  | Vice President

For themselves and the other

several Underwriters named in

Schedule I to the foregoing

Agreement.