Filed Pursuant to Rule 424(b)(5)
Registration Nos. 333-220576 and 333-220576-01

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and are not soliciting an offer to buy these securities in any jurisdiction where such offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED JUNE 14, 2018

PRELIMINARY PROSPECTUS SUPPLEMENT

(To Prospectus dated September 22, 2017)

$            

Digital Realty Trust, L.P.

             % Notes due 20    

fully and unconditionally guaranteed by

Digital Realty Trust, Inc.

We are offering $        aggregate principal amount of our     % notes due 20     (the “notes”). The notes will bear interest at the rate of     % per year and will mature on                     , 20    . Interest on the notes is payable on                  and                 of each year, beginning on                     , 2019. The notes will be fully and unconditionally guaranteed by Digital Realty Trust, Inc., a Maryland corporation, our sole general partner, which has no material assets other than its investment in us. We may redeem some or all of the notes at any time at the prices and as described under the caption “Description of Notes—Optional Redemption at Our Election.” If any notes are redeemed on or after      days prior to the maturity date of the notes, the redemption price will not include a make-whole premium.

The notes will be our unsecured senior obligations and will rank equally in right of payment with all of our other unsecured senior indebtedness from time to time outstanding and will be effectively subordinated in right of payment to all of our existing and future secured indebtedness and to all existing and future liabilities and preferred equity of our subsidiaries.

There is currently no market for the notes. We do not intend to list the notes on any national securities exchange or apply for quotation of the notes on any automated dealer quotation system.

Investing in the notes involves risks. See “Risk Factors” beginning on page S-13.

Neither the U.S. Securities and Exchange Commission (the “SEC”) nor any state securities commission or other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

The public offering prices set forth above do not include accrued interest, if any. Interest will accrue from                     , 2018 if settlement occurs after that date.

The underwriters expect to deliver the notes in book-entry form only through the facilities of The Depository Trust Company for the accounts of its participants against payment in New York, New York on                     , 2018.

Joint Book-Running Managers

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any “free writing prospectus” we authorize to be delivered to you. We have not, and the underwriters have not, authorized anyone else to provide you with different or additional information. If anyone provides you with different or additional information, you should not rely on it. We are not, and the underwriters are not, making an offer of these securities or soliciting an offer to buy these securities in any jurisdiction where the offer is not permitted. You should assume that the information appearing in this prospectus supplement and the accompanying prospectus, including the documents incorporated by reference herein and therein, and any authorized “free writing prospectus” is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since those dates. The descriptions set forth in this prospectus supplement replace and supplement, where inconsistent, the description of the general terms and provisions set forth in the accompanying prospectus.

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering and also adds to and updates information contained in the accompanying prospectus as well as the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus, gives more general information about securities we may offer from time to time, some of which does not apply to the notes we are offering. To the extent any inconsistency or conflict exists between the information included in this prospectus supplement and the information included in the accompanying prospectus, the information included or incorporated by reference in this prospectus supplement updates and supersedes the information in the accompanying prospectus. This prospectus supplement incorporates by reference important business and financial information about us that is not included in or delivered with this prospectus supplement.

It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectus in making your investment decision. You should also read and consider the information contained in the documents identified under the heading “Where You Can Find More Information.”

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus supplement and the accompanying prospectus to “we,” “us,” “our,” “the company” or “our company” refer to Digital Realty Trust, Inc. together with our consolidated subsidiaries, including Digital Realty Trust, L.P., a Maryland limited partnership, of which Digital Realty Trust, Inc. is the sole general partner and which we refer to in this prospectus supplement and the accompanying prospectus as “the operating partnership” or “our operating partnership”.

All references in this prospectus supplement to our operating partnership’s global revolving credit facility mean our operating partnership’s $2.0 billion senior unsecured revolving credit facility and global senior credit agreement, and all references in this prospectus supplement to our operating partnership’s term loan facility mean our operating partnership’s senior unsecured multi-currency term loan facility and term loan agreement, which governs a $1.25 billion five-year senior unsecured term loan and a $300 million seven-year senior unsecured term loan.

“Turn-Key Flex^®,” “Powered Base Buildings^®,” “POD Architecture^®” and “Critical Facilities Management^®” are trademarks of our company. All other trademarks or trade names appearing in this prospectus supplement and the accompanying prospectus are the property of their respective owners.

The distribution of this prospectus supplement, the accompanying prospectus and any authorized “free writing prospectus” in this offering may be restricted by law. If you possess this prospectus supplement, the accompanying prospectus or any authorized “free writing prospectus”, you should find out about and observe these restrictions. This prospectus supplement, the accompanying prospectus and any authorized “free writing prospectus” are not an offer to sell the notes and are not soliciting an offer to buy the notes in any jurisdiction where the offer or sale is not permitted or where the person making the offer or sale is not qualified to do so or to any person to whom it is not permitted to make such offer or sale. See “Underwriting (Conflicts of Interest)” in this prospectus supplement.

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RISK FACTORS

In addition to other information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any “free writing prospectus” we authorize to be delivered to you, you should carefully consider the risks described below and incorporated herein by reference to our Combined Annual Report on Form 10-K for the year ended December 31, 2017, and other subsequent filings of Digital Realty Trust, Inc. and Digital Realty Trust, L.P. under the Securities Exchange Act of 1934, as amended, or the Exchange Act, in evaluating our company, our properties and our business before making a decision to invest in the notes. These risks are not the only ones faced by us. Additional risks not presently known to us or that we currently deem immaterial could also materially and adversely affect our financial condition, results of operations, business and prospects. The trading price of the notes could decline due to any of these risks, and you may lose all or part of your investment. This prospectus supplement, the accompanying prospectus and the documents incorporated herein and therein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks faced by us described below and elsewhere in this prospectus supplement, the accompanying prospectus and the documents incorporated herein and therein by reference. Please refer to the section below entitled “Forward-Looking Statements.”

Risks Related to this Offering

Our substantial indebtedness could adversely affect our financial condition and ability to fulfill our obligations under the notes and otherwise adversely impact our business and growth prospects.

We have a substantial amount of debt. At March 31, 2018, our operating partnership (excluding its subsidiaries) had total indebtedness of approximately $5.4 billion, its subsidiaries had total indebtedness of approximately $3.8 billion and Digital Realty Trust, Inc. (excluding its subsidiaries) had no indebtedness, in each case exclusive of intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit. We may incur significant additional debt to finance future acquisition and development activities. Our operating partnership has a global revolving credit facility, under which approximately $1.1 billion was available at March 31, 2018, net of outstanding letters of credit. Our operating partnership also has a term loan facility, under which approximately $1.4 billion was outstanding as of March 31, 2018.

Our level of debt and the limitations imposed on us by our debt agreements could have significant adverse consequences to holders of the notes, including the following:

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If any one of these events were to occur, our financial condition, results of operations, cash flow and cash available for distribution, including our ability to satisfy our debt service obligations with respect to the notes, could be materially adversely affected. Furthermore, foreclosures could create taxable income without accompanying cash proceeds, a circumstance which could hinder Digital Realty Trust, Inc.’s ability to meet the REIT distribution requirements imposed by the Internal Revenue Code of 1986, as amended.

The effective subordination of the notes may limit our ability to satisfy our obligations under the notes.

The notes will be senior unsecured obligations of our operating partnership and will rank equally in right of payment with all of its other senior unsecured indebtedness. However, the notes will be effectively subordinated in right of payment to all of the secured indebtedness of our operating partnership to the extent of the value of the collateral securing such indebtedness. While the indenture governing the notes will limit the ability of our operating partnership and its subsidiaries to incur additional secured indebtedness in the future, it will not prohibit us from incurring such indebtedness if we are in compliance with certain financial ratios and other requirements. In the event of a bankruptcy, liquidation, dissolution, reorganization or similar proceeding with respect to us, the holders of any secured indebtedness will be entitled to proceed directly against the collateral that secures the secured indebtedness. Therefore, such collateral will not be available for satisfaction of any amounts owed under our operating partnership’s unsecured indebtedness, including the notes, until such secured indebtedness is satisfied in full. As of March 31, 2018, our operating partnership (excluding its subsidiaries) had approximately $5.4 billion of senior unsecured indebtedness and no secured indebtedness (exclusive of debt of its subsidiaries, intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit).

The notes also will be effectively subordinated to all liabilities and preferred equity of the subsidiaries of our operating partnership. In the event of a bankruptcy, liquidation, dissolution, reorganization or similar proceeding with respect to any such subsidiary, our operating partnership, as an equity owner of such subsidiary, and therefore holders of our operating partnership’s debt, including the notes, will be subject to the prior claims of such subsidiary’s creditors, including trade creditors, and preferred equity holders. As of March 31, 2018, our operating partnership’s subsidiaries had approximately $3.8 billion of total indebtedness, which includes approximately $106.2 million of secured indebtedness, exclusive of intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit. While the indenture governing the notes will limit the ability of our operating partnership’s subsidiaries to incur additional unsecured indebtedness in the future, it will not prohibit such subsidiaries from incurring such indebtedness if such subsidiaries are in compliance with certain financial ratios and other requirements.

We may not be able to generate sufficient cash flow to meet our debt service obligations.

Our ability to make payments on and to refinance our indebtedness, including the notes, and to fund our operations, working capital and capital expenditures, depends on our ability to generate cash in the future. To a certain extent, our cash flow is subject to general economic, industry, financial, competitive, operating, legislative, regulatory and other factors, many of which are beyond our control.

We cannot assure you that our business will generate sufficient cash flow from operations or that future sources of cash will be available to us in an amount sufficient to enable us to pay amounts due on our indebtedness, including the notes, or to fund our other liquidity needs. Additionally, if we incur additional indebtedness in connection with future acquisitions or development projects or for any other purpose, our debt service obligations could increase.

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We may need to refinance all or a portion of our indebtedness, including the notes, on or before maturity. Our ability to refinance our indebtedness or obtain additional financing will depend on, among other things:

As a result, we may not be able to refinance any of our indebtedness, including the notes, on commercially reasonable terms, or at all. If we do not generate sufficient cash flow from operations, and additional borrowings or refinancings or proceeds of asset sales or other sources of cash are not available to us, we may not have sufficient cash to enable us to meet all of our obligations, including payments on the notes. Accordingly, if we cannot service our indebtedness, we may have to take actions such as seeking additional equity or delaying capital expenditures or strategic acquisitions and alliances, any of which could have a material adverse effect on our operations. We cannot assure you that we will be able to effect any of these actions on commercially reasonable terms, or at all.

Despite our substantial indebtedness, we may still incur significantly more debt, which could exacerbate any or all of the risks described above.

We may be able to incur substantial additional indebtedness in the future. Although the agreements governing our operating partnership’s global revolving credit facility, term loan facility, and certain other indebtedness and the indentures governing our other senior notes limit and the indenture governing the notes will limit our ability to incur additional indebtedness, these restrictions are subject to a number of qualifications and exceptions and, under certain circumstances, debt incurred in compliance with these restrictions could be substantial. To the extent that we incur additional indebtedness or such other obligations, the risks associated with our substantial leverage described above, including our possible inability to service our debt, including the notes, would increase. In addition, the credit agreements governing our operating partnership’s global revolving credit facility and term loan facility, and the indentures governing our outstanding notes do not and the indenture governing the notes will not prevent us from incurring obligations that do not constitute indebtedness.

Digital Realty Trust, Inc. generally has no significant operations, other than as our operating partnership’s general partner, and no material assets, other than its investment in our operating partnership.

The notes will be fully and unconditionally guaranteed by Digital Realty Trust, Inc. However, Digital Realty Trust, Inc. generally has no significant operations, other than as our operating partnership’s general partner, and no material assets, other than its investment in us. Furthermore, Digital Realty Trust, Inc.’s guarantees of the notes will be effectively subordinated in right of payment to all unsecured and secured liabilities and preferred equity of its subsidiaries (including our operating partnership and any entity Digital Realty Trust, Inc. accounts for under the equity method of accounting). As of March 31, 2018, the total indebtedness, including capital lease obligations, of Digital Realty Trust, Inc.’s subsidiaries was approximately $9.5 billion (exclusive of intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit).

Federal and state statutes allow courts, under specific circumstances, to void guarantees and require holders of notes to return payments received from guarantors.

Under the federal bankruptcy law and comparable provisions of state fraudulent transfer laws, a guarantee, such as the guarantee provided by Digital Realty Trust, Inc., could be voided, or claims in respect of a guarantee could be subordinated to all other debts of that guarantor if, among other things, the guarantor, at the time it incurred the indebtedness evidenced by its guarantee:

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In addition, any payment by that guarantor pursuant to its guarantee could be voided and required to be returned to the guarantor, or to a fund for the benefit of the creditors of the guarantor.

The measures of insolvency for purposes of these fraudulent transfer laws will vary depending upon the law applied in any proceeding to determine whether a fraudulent transfer has occurred. Generally, however, a guarantor would be considered insolvent if:

The court might also void such guarantee, without regard to the above factors, if it found that a guarantor entered into its guarantee with actual or deemed intent to hinder, delay, or defraud its creditors.

A court would likely find that a guarantor did not receive reasonably equivalent value or fair consideration for its guarantee unless it benefited directly or indirectly from the issuance of the notes. If a court voided such guarantee, holders of the notes would no longer have a claim against such guarantor or the benefit of the assets of such guarantor constituting collateral that purportedly secured such guarantee. In addition, the court might direct holders of the notes to repay any amounts already received from a guarantor. If the court were to void Digital Realty Trust, Inc.’s guarantee, we cannot assure you that funds would be available to pay the notes from any of our subsidiaries or from any other source.

The indenture governing the notes will contain restrictive covenants that limit our operating flexibility.

The indenture governing the notes will contain financial and operating covenants that, among other things, will restrict our ability to take specific actions, even if we believe them to be in our best interest, including restrictions on:

In addition, our operating partnership’s global revolving credit facility, term loan facility, and indentures governing our other senior notes require us to meet specified financial ratios and the indenture governing the notes will require our operating partnership and its subsidiaries to maintain at all times a specified ratio of unencumbered assets to unsecured debt. These covenants may restrict our ability to expand or fully pursue our business strategies. Our ability to comply with these and other provisions of the indenture governing the notes, our operating partnership’s global revolving credit facility and term loan facility, and indentures governing our other senior notes may be affected by changes in our operating and financial performance, changes in general business and economic conditions, adverse regulatory developments or other events beyond our control. The breach of any of these covenants could result in a default under our indebtedness, which could cause those and other obligations to become due and payable. If any of our indebtedness is accelerated, we may not be able to repay it.

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Our management will have broad discretion in allocating the net proceeds of this offering.

Our management has significant flexibility in applying the net proceeds we expect to receive in this offering. We intend to use the net proceeds from this offering as described in “Use of Proceeds,” but because the net proceeds are not required to be allocated to any specific investment or transaction, you cannot determine at this time the value or propriety of our application of the net proceeds, and you may not agree with our decisions. In addition, our use of the net proceeds from this offering may not yield a significant return or any return at all. The failure by our management to apply these funds effectively could have a material adverse effect on our financial condition, results of operations, business or prospects. See “Use of Proceeds.”

There is no prior public market for the notes, and if an active trading market does not develop for the notes, you may not be able to resell them.

Prior to this offering, there was no public market for the notes and we cannot assure you that an active trading market will ever develop for the notes. Although we have registered the offer and sale of the notes under the Securities Act of 1933, as amended, or the Securities Act, we do not intend to apply for listing of the notes on any securities exchange or for quotation of the notes on any automated dealer quotation system. The underwriters have informed us that they currently intend to make a market in the notes after this offering is completed. However, the underwriters may cease their market making at any time. The lack of a trading market could adversely affect your ability to sell the notes and the price at which you may be able to sell the notes. The liquidity of the trading market, if any, and future trading prices of the notes will depend on many factors, including, among other things, prevailing interest rates, our operating results, financial performance and prospects, the market for similar securities and the overall securities market, and may be adversely affected by unfavorable changes in these factors. It is possible that the market for the notes will be subject to disruptions which may have a negative effect on the holders of the notes, regardless of our operating results, financial performance or prospects.

A downgrade in our credit ratings could materially adversely affect our business and financial condition and the market value of the notes.

The credit ratings assigned to the notes and other debt securities of our operating partnership and the preferred stock of Digital Realty Trust, Inc. could change based upon, among other things, our results of operations and financial condition. These ratings are subject to ongoing evaluation by credit rating agencies, and we cannot assure you that any rating will not be changed or withdrawn by a rating agency in the future if, in its judgment, circumstances warrant. Moreover, these credit ratings are not recommendations to buy, sell or hold the notes or any other securities. If any of the credit rating agencies that have rated the notes or other debt securities of our operating partnership or the preferred stock of Digital Realty Trust, Inc. downgrades or lowers its credit rating, or if any credit rating agency indicates that it has placed any such rating on a so-called “watch list” for a possible downgrading or lowering or otherwise indicates that its outlook for that rating is negative, it could have a material adverse effect on the market value of the notes and our costs and availability of capital, which could in turn have a material adverse effect on our financial condition, results of operations, cash flows and our ability to satisfy our debt service obligations (including payments on the notes) and to make dividends and distributions to our security holders.

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FORWARD-LOOKING STATEMENTS

We make statements in this prospectus supplement, the accompanying prospectus and the documents incorporated herein and therein by reference that are forward-looking statements within the meaning of the federal securities laws. In particular, statements pertaining to our capital resources, expected use of net proceeds from this offering, expected use of borrowings under our credit facility, portfolio performance, our ability to lease vacant space and space under development, leverage policy, acquisition and capital expenditure plans, capital recycling program, returns on invested capital, supply and demand for data center space, capitalization rates, expected proceeds from assets sales and cash flows from operations, rents to be received in future periods and expected rental rates on new or renewed data center space contain forward-looking statements. Likewise, all of our statements regarding anticipated market conditions, demographics and results of operations are forward-looking statements. You can identify forward-looking statements by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “seeks,” “approximately,” “intends,” “plans,” “pro forma,” “estimates” or “anticipates” or the negative of these words and phrases or similar words or phrases which are predictions of or indicate future events or trends and discussions which do not relate solely to historical matters. You can also identify forward-looking statements by discussions of strategy, plans or intentions.

Forward-looking statements involve numerous risks and uncertainties and you should not rely on them as predictions of future events. Forward-looking statements depend on assumptions, data or methods that may be incorrect or imprecise and that we may not be able to realize. We do not guarantee that the transactions and events described will happen as described or that they will happen at all. The following factors, among others, could cause actual results and future events to differ materially from those set forth or contemplated in the forward-looking statements:

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While forward-looking statements reflect our good faith beliefs, they are not guarantees of future performance. We disclaim any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors, new information, data or methods, future events or other changes. The risks included here are not exhaustive, and additional factors could adversely affect our business and financial performance, including factors and risks included in other sections of this prospectus supplement, the accompanying prospectus or the documents incorporated by reference herein or therein. Those risks continue to be relevant to our performance and financial condition. Moreover, we operate in a very competitive and rapidly changing environment. New risk factors emerge from time to time and it is not possible for management to predict all such risk factors, nor can we assess the impact of all such risk factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Given these risks and uncertainties, investors should not place undue reliance on forward-looking statements as a prediction of actual results. For a further discussion of these and other factors that could impact our future results, performance or transactions, see the section entitled “Risk Factors” in this prospectus supplement, in the accompanying prospectus and in our Combined Annual Report on Form 10-K for the year ended December 31, 2017, as may be updated by subsequent filings with the SEC that are incorporated by reference herein and therein.

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USE OF PROCEEDS

We expect that the net proceeds from this offering will be approximately $        million after deducting underwriters’ discounts and our estimated expenses of approximately $        million.

We intend to use the net proceeds from this offering to repay borrowings outstanding under our operating partnership’s global revolving credit facility and to acquire additional properties or businesses, fund development opportunities, to provide for working capital and other general corporate purposes, including potentially for the repayment of debt or the repurchase, redemption or retirement of outstanding debt or equity securities, or a combination of the foregoing.

Our operating partnership’s global revolving credit facility provides for borrowings in Australian dollars, British pound sterling, Canadian dollars, Euros, Hong Kong dollars, Japanese yen, Singapore dollars, and U.S. dollars, and includes the ability to add additional currencies in the future, subject to the receipt of lender commitments in such currencies and the satisfaction of other conditions. As of March 31, 2018, our operating partnership’s global revolving credit facility had a total outstanding balance of $958.5 million, excluding committed letters of credit of $22.9 million, leaving approximately $1.1 billion available for use. As of March 31, 2018, borrowings under operating partnership’s global revolving credit facility bore interest at an overall blended rate of 2.52% comprised of 2.78% (U.S. dollars), 1.51% (British pound sterling), 0.62% (Euro), 2.77% (Australian dollars), 1.84% (Hong Kong dollars), 0.92% (Japanese yen), 2.60% (Canadian dollars) and 4.75% (U.S. dollars). The interest rates are based on 1-month LIBOR, 1-month GBP LIBOR, 1-month EURIBOR, 1-month BBR, 1-month HIBOR, 1-month JPY LIBOR and 1-month CDOR, respectively, plus a margin of 1.00%, and U.S. Prime Rate. We have used and intend to use borrowings under our operating partnership’s global revolving credit facility to acquire additional properties or businesses, fund development opportunities and to provide for working capital and other corporate purposes, including potentially for the repurchase, redemption or retirement of outstanding debt or equity securities.

Affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC and U.S. Bancorp Investments, Inc. are lenders, affiliates of SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are co-documentation agents, affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC are syndication agents, Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC and affiliates of SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are joint lead arrangers and joint book running managers, and affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC are issuing banks under our operating partnership’s global revolving credit facility. Therefore, such underwriters and/or affiliates of such underwriters may receive more than 5% of the net proceeds from this offering through the repayment of the borrowings under the global revolving credit facility.

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CAPITALIZATION

The following table sets forth Digital Realty Trust, L.P.’s capitalization as of March 31, 2018:

This information should be read in conjunction with, and is qualified in its entirety by, Digital Realty Trust, L.P.’s consolidated financial statements and schedule and the notes to its financial statements included in our Combined Quarterly Report on Form 10-Q for the three months ended March 31, 2018 and our Combined Annual Report on Form 10-K for the year ended December 31, 2017, each of which is incorporated by reference in this prospectus supplement and the accompanying prospectus.

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DESCRIPTION OF NOTES

The following description of the terms of the notes (referred to in the accompanying prospectus as the “debt securities”) supplements, and to the extent inconsistent, replaces the description of the general terms and provisions of the debt securities set forth in the accompanying prospectus. The following description does not purport to be complete and is subject to, and qualified in its entirety by reference to, the actual terms and provisions of the notes and the indenture, which are incorporated herein by reference. Capitalized terms used but not otherwise defined herein shall have the meanings given to them in the notes or the indenture, as applicable. As used in this section, the terms “we,” “us,” “our” or “Digital Realty Trust, L.P.” refer only to Digital Realty Trust, L.P. and not to any of its subsidiaries or Digital Realty Trust, Inc.

General

The notes will be issued pursuant to an indenture, dated as of June 23, 2015, and a supplemental indenture (together, the “indenture”), to be dated as of                     , 2018, among Digital Realty Trust, L.P., as issuer, Digital Realty Trust, Inc., as guarantor, and Wells Fargo Bank, National Association, as trustee. You may request copies of the indenture and the form of the notes from us.

The notes will be senior unsecured obligations of Digital Realty Trust, L.P. and will rank equally in right of payment with each other and with all of Digital Realty Trust, L.P.’s other senior unsecured indebtedness. However, the notes will be effectively subordinated in right of payment to Digital Realty Trust, L.P.’s mortgages and its other secured indebtedness (to the extent of the value of the collateral securing the same) and to all preferred equity and liabilities, whether secured or unsecured, of Digital Realty Trust, L.P.’s subsidiaries. As of March 31, 2018, Digital Realty Trust, L.P. had outstanding $5.4 billion of senior unsecured indebtedness (exclusive of intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit) and subsidiaries of Digital Realty Trust, L.P. had approximately $3.8 billion of total indebtedness, which includes approximately $106.2 million of secured indebtedness, excluding intercompany debt, guarantees of debt, trade payables, distributions payable, accrued expenses and committed letters of credit. See “Risk Factors—Our substantial indebtedness could adversely affect our financial condition and ability to fulfill our obligations under the notes and otherwise adversely impact our business and growth prospects” and “Risk Factors—The effective subordination of the notes may limit our ability to satisfy our obligations under the notes.” As of March 31, 2018, our global revolving credit facility had a total outstanding balance of $958.5 million, excluding committed letters of credit of $22.9 million, leaving approximately $1.1 billion available for use, and $1.4 billion was outstanding under our term loan facility.

The notes will initially be limited to an aggregate principal amount of $         million. We may from time to time, without notice to or consent of existing note holders, create and issue additional notes having the same terms and conditions as the notes offered by this prospectus supplement in all respects, except for the issue date and, under certain circumstances, the issue price and first payment of interest thereon, provided that such issuance complies with the covenants described under “—Certain Covenants.” Additional notes issued in this manner will be consolidated with and will form a single series with the previously outstanding notes, provided, however, that if such additional notes will not be fungible with the previously outstanding notes for U.S. federal income tax purposes, such additional notes will have a separate CUSIP number. The notes offered by this prospectus supplement and any additional notes would rank equally and ratably in right of payment and would be treated as a single series of debt securities for all purposes under the indenture.

The notes will be issued only in fully registered, book-entry form, in denominations of $2,000 and integral multiples of $1,000 in excess thereof, except under the limited circumstances described below under “—Book-Entry, Delivery and Form.” The registered holder of a note will be treated as its owner for all purposes.

If any interest payment date, stated maturity date, redemption date or repurchase date is not a business day, the payment otherwise required to be made on such date will be made on the next business day without any additional payment as a result of such delay. All payments will be made in U.S. dollars.

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The terms of the notes provide that we are permitted to withhold from interest payments and payments upon a redemption or maturity of the notes any amounts we are required to withhold by law. For example, non-United States holders of notes may, under some circumstances, be subject to U.S. federal withholding tax with respect to payments of interest on the notes. See “United States Federal Income Tax Considerations—Taxation of Holders of the Operating Partnership’s Debt Securities—Non-U.S. Holders” in Exhibit 99.1 to our Current Report on Form 8-K filed with the SEC on June 14, 2018.

Except as described in this prospectus supplement under the headings “—Certain Covenants—Limitations on Incurrence of Indebtedness” and “—Merger, Consolidation or Sale,” the indenture will not contain any provisions that would limit our ability to incur indebtedness or that would afford you protection in the event of:

We or one of our affiliates may, to the extent permitted by applicable law, at any time purchase notes in the open market, by tender at any price or by private agreement. Any notes so repurchased may not be reissued or resold and will be canceled promptly.

Guarantee

Digital Realty Trust, Inc. will fully and unconditionally guarantee our obligations under the notes on a senior unsecured basis, including the due and punctual payment of principal of and interest and premium, if any, on the notes, whether at stated maturity, by declaration of acceleration, call for redemption, notice of repurchase or otherwise. The guarantee will be a senior unsecured obligation of Digital Realty Trust, Inc. and will rank equally in right of payment with other senior unsecured obligations of Digital Realty Trust, Inc.

Interest

Interest on the notes will accrue at the rate of     % per year from and including                 , 2018 or the most recent interest payment date to which interest has been paid or provided for, and will be payable semiannually in arrears on              and              of each year, beginning on                 , 2019.

The interest so payable will be paid to each holder in whose name a note is registered at the close of business on the              or              (whether or not a business day) immediately preceding the interest payment date. Interest on the notes will be computed on the basis of a 360-day year consisting of twelve 30-day months.

If we redeem the notes in accordance with the terms of such notes, we will pay accrued and unpaid interest and premium, if any, to the holder that surrenders such notes for redemption. However, if a redemption falls after a record date and on or prior to the corresponding interest payment date, we will pay the full amount of accrued and unpaid interest and premium, if any, due on such interest payment date to the holder of record at the close of business on the corresponding record date.

Maturity

The notes will mature on                     , 20         and will be paid against presentation and surrender thereof at the corporate trust office of the trustee unless earlier redeemed by us at our option, as described under “—Optional Redemption at Our Election” below. The notes will not be entitled to the benefits of, or be subject to, any sinking fund.

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Optional Redemption at Our Election

We may redeem on any one or more occasions some or all of the notes before they mature. The redemption price will equal the sum of (1) an amount equal to one hundred percent (100%) of the principal amount of the notes being redeemed plus accrued and unpaid interest up to, but not including, the redemption date and (2) a make-whole premium. Notwithstanding the foregoing, if the notes are redeemed on or after              days prior to the maturity date, the redemption price will not include a make-whole premium.

We will calculate the make-whole premium with respect to any notes redeemed before the                 th day prior to the maturity date of the notes as the excess, if any, of:

“Reinvestment Rate” means             percent (    %), plus the arithmetic mean of the yields under the respective headings “This Week” and “Last Week” published in the most recent Federal Reserve Statistical Release H.15 (519) that has become publicly available prior to the date of determining the make-whole premium (or if such statistical release is no longer published, any such other reasonably comparable index which shall be designated by us) under the caption “Treasury Constant Maturities” for the maturity (rounded to the nearest month) corresponding to the then remaining maturity of the notes. If no maturity exactly corresponds to such maturity of the notes, the applicable Reinvestment Rate will be obtained by linear interpolation (calculated to the nearest one-twelfth of a year) from the yields for the two published maturities most closely corresponding to such maturity of the notes.

We will give you notice of any optional redemption at your address, as shown in the security register, at least 15, but not more than 60, days before the redemption date. The notice of redemption will specify, among other items, the redemption price and the principal amount of the notes held by such holder to be redeemed.

If we decide to redeem the notes in part, the trustee will select the notes to be redeemed (in principal amounts of $2,000 and integral multiples of $1,000 in excess thereof) on a pro rata basis, by lot or such other method it deems fair and appropriate or as required by the depository for the notes. In the event of any redemption of the notes in part, we will not be required to:

If the paying agent holds funds sufficient to pay the redemption price of the notes on the redemption date, then on and after such date:

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Such will be the case whether or not book-entry transfer of the notes in book-entry form is made and whether or not notes in certificated form, together with the necessary endorsements, are delivered to the paying agent.

We will not redeem the notes on any date if the principal amount of the notes has been accelerated, and such an acceleration has not been rescinded or cured on or prior to such date.

Certain Covenants

Limitations on Incurrence of Indebtedness.

Limitation on Total Outstanding Debt. We will not, and will not permit any of our Subsidiaries to, Incur any Indebtedness, other than Intercompany Indebtedness and guarantees of Indebtedness Incurred by us or any of our Subsidiaries in compliance with the indenture governing the notes, if, immediately after giving effect to the Incurrence of such Indebtedness and the application of the proceeds thereof, Total Outstanding Debt would be greater than 60% of Total Assets as of the end of the fiscal quarter covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be.

Secured Debt. In addition to the preceding limitation on the Incurrence of Indebtedness, we will not, and will not permit any of our Subsidiaries to, Incur any Secured Debt, other than guarantees of Secured Debt Incurred by us or any of our Subsidiaries in compliance with the indenture governing the notes, if, immediately after giving effect to the Incurrence of such Secured Debt and the application of the proceeds thereof, the aggregate principal amount of Secured Debt would be greater than 40% of Total Assets as of the end of the fiscal quarter covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be.

Unencumbered Assets. We and our Subsidiaries will at all times maintain Total Unencumbered Assets of not less than 150% of the aggregate outstanding principal amount of Unsecured Debt.

Ratio of Consolidated EBITDA to Interest Expense. In addition to the preceding limitations on the Incurrence of Indebtedness, we will not, and will not permit any of our Subsidiaries to, Incur any Indebtedness other than Intercompany Indebtedness and guarantees of Indebtedness Incurred by us or any of our Subsidiaries in compliance with the indenture governing the notes, if the ratio of Consolidated EBITDA to Interest Expense for the most recent quarterly period covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be, in the manner described under “—Reports,” prior to such time, annualized (i.e., multiplied by four (4)) prior to the date on which such additional Indebtedness is to be Incurred shall have been less than 1.50:1.00 on a pro forma basis after giving effect thereto and to the application of the proceeds therefrom, and calculated on the assumption that:

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Reports. Whether or not required by the rules and regulations of the SEC, so long as any notes are outstanding, we will furnish to the holders of the notes or cause the trustee to furnish to the holders of the notes, within the time periods specified in the SEC’s rules and regulations:

All such reports will be prepared in all material respects in accordance with all of the rules and regulations applicable to such reports. Each annual report on Form 10-K will include a report on our consolidated financial statements by our independent registered public accounting firm. In addition, we will file a copy of each of the reports referred to above with the SEC for public availability within the time periods specified in the rules and regulations applicable to such reports (unless the SEC will not accept such a filing) and will make the reports available on our website within those time periods.

If, at any time we are not subject to the periodic reporting requirements of the Exchange Act for any reason, we will nevertheless continue filing the reports specified in the preceding paragraphs of this covenant with the SEC within the time periods specified above unless the SEC will not accept such a filing. We will not take any action for the purpose of causing the SEC not to accept any such filings. If, notwithstanding the foregoing, the SEC will not accept our filings for any reason, we will post the reports referred to in the preceding paragraphs on our website within the time periods that would apply if we were required to file those reports with the SEC.

Certain Definitions

Set forth below are certain defined terms used in this prospectus supplement and the indenture. We refer you to the indenture for a full disclosure of all such terms, as well as any other capitalized terms used in this prospectus supplement for which no definition is provided.

“Acquired Indebtedness” means Indebtedness of a Person (1) existing at the time such Person becomes a Subsidiary or (2) assumed in connection with the acquisition of assets from such Person, in each case, other than Indebtedness Incurred in connection with, or in contemplation of, such Person becoming a Subsidiary or such acquisition. Acquired Indebtedness shall be deemed to be Incurred on the date of the related acquisition of assets from any Person or the date the acquired Person becomes a Subsidiary.

“Capitalization Rate” means 8.25%.

“Consolidated EBITDA” means, for any period of time, without duplication, consolidated net income (loss) of Digital Realty Trust, L.P. and its Consolidated Subsidiaries plus amounts which have been deducted and

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minus amounts which have been added for, without duplication, (a) Interest Expense, (b) depreciation and amortization and other non-cash items deducted or added in arriving at net income (loss), (c) provision for taxes based on income or profits, (d) non-recurring or other unusual items, as determined by us in good faith (including, without limitation, all prepayment penalties and all costs or fees incurred in connection with any debt financing or amendment thereto, acquisition, disposition, recapitalization or similar transaction (regardless of whether such transaction is completed)), (e) extraordinary items, (f) noncontrolling interests, (g) the income or expense attributable to transactions involving derivative instruments that do not qualify for hedge accounting in accordance with GAAP, and (h) gains or losses on dispositions of depreciable real estate investments, property valuation losses and impairment charges; provided, however, that in no event will Consolidated EBITDA include (x) net income (loss) (whether pursuant to the equity method of accounting or otherwise) on account of any of our or our Consolidated Subsidiaries’ unconsolidated subsidiaries and other partially owned entities or (y) net income (loss) generated from our or our Consolidated Subsidiaries’ real property under construction or Redevelopment Properties; provided, further, that all amounts for such period shall be reasonably determined by us in accordance with GAAP to the extent GAAP is applicable. Consolidated EBITDA will be adjusted, without duplication, to give pro forma effect: (i) in the case of any assets having been placed in service or removed from service from the beginning of the period to the date of determination, to include or exclude, as the case may be, any Consolidated EBITDA earned or eliminated as a result of the placement of the assets in service or removal of the assets from service as if the placement of the assets in service or removal of the assets from service occurred at the beginning of the period; and (ii) in the case of any acquisition or disposition of any asset or group of assets from the beginning of the period to the date of determination, including, without limitation, by merger, or stock or asset purchase or sale, to include or exclude, as the case may be, any Consolidated EBITDA earned or eliminated as a result of the acquisition or disposition of those assets as if the acquisition or disposition occurred at the beginning of the period.

“Consolidated Financial Statements” means, with respect to any Person, collectively, the consolidated financial statements and notes to those financial statements, of that Person and its Consolidated Subsidiaries prepared in accordance with GAAP.

“Consolidated Subsidiary” means each Subsidiary of Digital Realty Trust, L.P. that is consolidated in the Consolidated Financial Statements of Digital Realty Trust, L.P.

“GAAP” means generally accepted accounting principles in the United States of America as in effect from time to time.

“Incur” means, with respect to any Indebtedness or other obligation of any Person, to create, assume, guarantee or otherwise become liable in respect of the Indebtedness or other obligation, and “Incurrence” and “Incurred” have meanings correlative to the foregoing. Indebtedness or other obligation of us or any Subsidiary of ours will be deemed to be Incurred by us or such Subsidiary whenever we or such Subsidiary shall create, assume, guarantee or otherwise become liable in respect thereof. Indebtedness or other obligation of a Subsidiary of ours existing prior to the time it became a Subsidiary of ours will be deemed to be Incurred upon such Subsidiary becoming a Subsidiary of ours; and Indebtedness or other obligation of a Person existing prior to a merger or consolidation of such Person with us or any Subsidiary of ours in which such Person is the successor to us or such Subsidiary will be deemed to be Incurred upon the consummation of such merger or consolidation. Any issuance or transfer of capital stock that results in Indebtedness constituting Intercompany Indebtedness being held by a Person other than us, Digital Realty Trust, Inc. or any Consolidated Subsidiary or any sale or other transfer of any Indebtedness constituting Intercompany Indebtedness to a Person that is not us, Digital Realty Trust, Inc. or any Consolidated Subsidiary, will be deemed, in each case, to be an Incurrence of Indebtedness that is not Intercompany Indebtedness at the time of such issuance, transfer or sale, as the case may be.

“Indebtedness” of us, Digital Realty Trust, Inc. or any Consolidated Subsidiary means, without duplication, any of our indebtedness or that of any Consolidated Subsidiary, whether or not contingent, in respect of:

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(a) borrowed money evidenced by bonds, notes, debentures or similar instruments whether or not such indebtedness is secured by any lien existing on property owned by us or any Consolidated Subsidiary; (b) indebtedness for borrowed money of a Person other than us, Digital Realty Trust, Inc. or a Consolidated Subsidiary which is secured by any lien on property owned by us, Digital Realty Trust, Inc. or any Consolidated Subsidiary, to the extent of the lesser of (i) the amount of indebtedness so secured, and (ii) the fair market value of the property subject to such lien; (c) the reimbursement obligations, contingent or otherwise, in connection with any letters of credit actually issued or amounts representing the balance deferred and unpaid of the purchase price of any property or services, except any such balance that constitutes an accrued expense or trade payable; or (d) any lease of property by us, Digital Realty Trust, Inc. or any Consolidated Subsidiary as lessee which is reflected on our consolidated balance sheet as a capitalized lease in accordance with GAAP. Indebtedness also includes, to the extent not otherwise included, any obligation by us, Digital Realty Trust, Inc. or any Consolidated Subsidiary to be liable for, or to pay, as obligor, guarantor or otherwise (other than for purposes of collection in the ordinary course of business), indebtedness of another Person (other than us or any of our Consolidated Subsidiaries) of the type described in clauses (a)-(d) of this definition.

“Intercompany Indebtedness” means Indebtedness to which the only parties are any of us, Digital Realty Trust, Inc. and any Consolidated Subsidiary; provided, however, that with respect to any such Indebtedness of which we or Digital Realty Trust, Inc. is the borrower, such Indebtedness is subordinate in right of payment to the notes.

“Interest Expense” means, for any period of time, consolidated interest expense for such period of time, whether paid, accrued or capitalized, without deduction of consolidated interest income, of Digital Realty Trust, L.P. and its Consolidated Subsidiaries, including, without limitation or duplication, or, to the extent not so included, with the addition of (a) the portion of any rental obligation in respect of any capital lease obligation allocable to interest expense in accordance with GAAP and (b) the amortization of Indebtedness discounts, but excluding prepayment penalties, in all cases as reflected in the applicable Consolidated Financial Statements.

“Person” means a corporation, an association, a partnership, a limited liability company, an individual, a joint venture, a joint stock company, a trust, an unincorporated organization or a government or an agency or a political subdivision thereof.

“Redevelopment Property” means a property owned by us or a Consolidated Subsidiary (a) where the commenced leased square footage is less than 60% of the sum of net rentable square feet and redevelopment space, with reasonable adjustments to leased square footage determined in good faith by us, including adjustments for available power, required support space and common area and (b) that we reasonably characterize as held in whole or in part for redevelopment.

“Secured Debt” means, as of any date, that portion of Total Outstanding Debt as of that date that is secured by a mortgage, trust deed, deed of trust, deeds to secure Indebtedness, pledge, security interest, assignment for collateral purposes, deposit arrangement, or other security agreement, excluding any right of setoff but including, without limitation, any conditional sale or other title retention agreement, any financing lease having substantially the same economic effect as any of the foregoing, and any other like agreement granting or conveying a security interest.

“Subsidiary” means, with respect to any Person, (a) any corporation, association or other business entity of which more than 50% of the total voting power of shares of capital stock or other equity interest entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other subsidiaries of that Person (or a combination thereof) and (b) any partnership (i) the sole general partner or managing general partner of which is such Person or a subsidiary of such Person or (ii) the only general partners of which are such Person or of one or more subsidiaries of such Person (or any combination thereof).

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“Total Assets” as of any date means the sum, without duplication, of (a) Consolidated EBITDA for the most recent quarterly period covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be, in the manner described under “—Reports,” prior to such time, annualized (i.e., multiplied by four (4)), capitalized at the Capitalization Rate, (b) the undepreciated cost basis of our and our Consolidated Subsidiaries’ real property under construction and Redevelopment Property as of the end of the quarterly period used for purposes of clause (a) above, in each case as determined by us in good faith, and (c) for all assets of us and our Consolidated Subsidiaries other than the assets referred to in (a) and (b) above, the undepreciated book value as determined in accordance with GAAP (but excluding accounts receivable and intangible assets).

“Total Outstanding Debt” means, as of any date, the sum, without duplication, of (1) the aggregate principal amount of all outstanding Indebtedness of Digital Realty Trust, L.P. as of that date, excluding Intercompany Indebtedness; and (2) the aggregate principal amount of all outstanding Indebtedness of Digital Realty Trust, L.P.’s Consolidated Subsidiaries, all as of that date, excluding Intercompany Indebtedness.

“Total Unencumbered Assets” means, as of any time, the sum of (a) Unencumbered Consolidated EBITDA for the most recent quarterly period covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be, in the manner described under “—Reports,” prior to such time, annualized (i.e., multiplied by four (4)), capitalized at the Capitalization Rate, and (b) to the extent not subject to any Secured Debt, the value of the assets described in clauses (b) and (c) of the definition of Total Assets; provided, however, that all investments by us and our Subsidiaries in unconsolidated joint ventures, unconsolidated limited partnerships, unconsolidated limited liability companies and other unconsolidated entities shall be excluded from Total Unencumbered Assets to the extent that such investments would have otherwise been included.

“Unencumbered Consolidated EBITDA” means, for any quarter, Consolidated EBITDA for the most recent quarterly period covered in our annual or quarterly report most recently furnished to holders of the notes or filed with the SEC, as the case may be, in the manner described under “—Reports,” prior to the time of determination, less any portion thereof attributable to any properties or assets subject to any Secured Debt, as determined in good faith by us.

“Unsecured Debt” means that portion of Total Outstanding Debt that is not Secured Debt.

No Protection in the Event of a Change of Control

The notes will not contain any provisions that may afford holders of the notes protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) that could adversely affect holders of the notes.

Merger, Consolidation or Sale

Digital Realty Trust, L.P. and Digital Realty Trust, Inc. may consolidate with, or sell, lease or convey all or substantially all of their respective assets to, or merge with or into, any other entity, provided that the following conditions are met:

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Events of Default

The indenture provides that the following events are “Events of Default” with respect to the notes:

If an Event of Default under the indenture with respect to the notes occurs and is continuing (other than an Event of Default specified in the last bullet above, which shall result in an automatic acceleration), then, in every case, the trustee or the holders of not less than 25% in principal amount of the outstanding notes may declare the principal amount of all of the notes, to be due and payable immediately by written notice thereof to Digital Realty Trust, L.P. (and to the trustee if given by the holders). However, at any time after the declaration of acceleration with respect to the notes has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of outstanding notes may rescind and annul the declaration and its consequences if:

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The trustee will be required to give notice to the holders of the notes within 90 days of a default with respect to the notes actually known to the trustee under the indenture unless the default has been cured or waived; provided, however, that the trustee may withhold notice to the holders of the notes of any default with respect to the notes (except a default in the payment of the principal of or interest and premium on the notes) if the trustee considers such withholding to be in the interest of the holders of the notes.

The indenture provides that no holder of the notes may institute any proceedings, judicial or otherwise, with respect to the indenture or for any remedy thereunder, except in the case of failure of the trustee, for 60 days, to act after it has received a written request to institute proceedings in respect of an event of default with respect to the notes from the holders of not less than 25% in principal amount of the outstanding notes, as well as an offer of indemnity satisfactory to the trustee. This provision will not prevent, however, any holder of the notes from instituting suit for the enforcement of payment of the principal of and interest or premium on the notes at the respective due dates thereof.

Subject to provisions in the indenture relating to its duties in case of default, the trustee is under no obligation to exercise any of its rights or powers under the indenture at the request or direction of any holders of the notes then outstanding under the indenture, unless the holders of the notes shall have offered to the trustee security or indemnity reasonably satisfactory to it. The holders of a majority in principal amount of the outstanding notes (or of all the notes then outstanding under the indenture, as the case may be) shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred upon the trustee. However, the trustee may refuse to follow any direction which is in conflict with any law or the indenture, or which a responsible officer of the trustee determines would involve the trustee in personal liability.

Within 120 days after the close of each fiscal year, Digital Realty Trust, L.P. and Digital Realty Trust, Inc. must deliver an officers’ certificate certifying to the trustee whether or not the signing officers have knowledge of any default under the indenture and, if so, specifying each default and the nature and status thereof.

Modification, Waiver and Meetings

Modifications and amendments of the indenture will be permitted to be made only with the consent of the holders of not less than a majority in principal amount of all outstanding notes; provided, however, that no modification or amendment may, without the consent of each holder affected:

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Notwithstanding the foregoing, modifications and amendments of the indenture will be permitted to be made by Digital Realty Trust, L.P., Digital Realty Trust, Inc. and the trustee without the consent of any holder of the notes for any of the following purposes:

In determining whether the holders of the requisite principal amount of outstanding notes have given any request, demand, authorization, direction, notice, consent or waiver thereunder or whether a quorum is present at a meeting of holders of notes, the indenture provides that notes owned by Digital Realty Trust, L.P. or any other obligor upon the notes or any affiliate of Digital Realty Trust, L.P. or of the other obligor shall be disregarded.

The indenture contains provisions for convening meetings of the holders of notes. A meeting will be permitted to be called at any time by the trustee, and also, upon request, by Digital Realty Trust, L.P., Digital Realty Trust, Inc. or the holders of at least 10% in principal amount of the outstanding notes, in any case upon notice given as provided in the indenture. Except for any consent that must be given by the holder of each note affected by certain modifications and amendments of the indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present will be permitted to be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding notes; provided, however, that, except as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority, in principal amount of the outstanding notes may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of the specified percentage in principal amount of the outstanding notes. Any resolution passed or decision taken at any meeting of holders of notes duly held in accordance with the indenture will be binding on all holders of the notes. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, will be holders holding or representing a majority in principal amount of the outstanding notes; provided, however, that if any action is to

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be taken at the meeting with respect to a consent or waiver which may be given by the holders of not less than a specified percentage in principal amount of the outstanding notes, holders holding or representing the specified percentage in principal amount of the outstanding notes will constitute a quorum.

Notwithstanding the foregoing provisions, any action to be taken at a meeting of holders of the notes with respect to any action that the indenture expressly provides may be taken by the holders of a specified percentage which is less than a majority in principal amount of the outstanding notes may be taken at a meeting at which a quorum is present by the affirmative vote of holders of the specified percentage in principal amount of the outstanding notes.

Trustee

Wells Fargo Bank, National Association will initially act as the trustee, registrar and paying agent for the notes, subject to replacement at our option.

If an Event of Default occurs and is continuing, the trustee will be required to use the degree of care and skill of a prudent person in the conduct of his or her own affairs. The trustee will become obligated to exercise any of its powers under the indenture at the request of any of the holders of any notes only after those holders have offered the trustee indemnity satisfactory to it.

If the trustee becomes one of our creditors, it will be subject to limitations on its rights to obtain payment of claims or to realize on some property received for any such claim, as security or otherwise. The trustee is permitted to engage in other transactions with us. If, however, it acquires any conflicting interest, it must eliminate that conflict or resign.

No Personal Liability of Directors, Officers, Employees and Stockholders

No director, officer, employee, incorporator, stockholder, member or partner of Digital Realty Trust, L.P. or Digital Realty Trust, Inc. or any of their respective Subsidiaries, as such, will have any liability for any obligations of Digital Realty Trust, L.P. or Digital Realty Trust, Inc. under the notes, the indenture, the guarantee or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each holder of the notes by accepting a note waives and releases all such liability. The waiver and release are part of the consideration for issuance of the notes. The waiver may not be effective to waive liabilities under the federal securities laws.

Book-Entry, Delivery and Form

The notes will be represented by one or more global notes that will be deposited with, or on behalf of, the Depository Trust Company, or DTC, and registered in the name of Cede & Co., the nominee of DTC.

DTC has advised us and the underwriters that it is:

DTC was created to hold securities of its participating organizations, or participants, and to facilitate the clearance and settlement of securities transactions, such as transfers and pledges, among its participants in such

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securities through electronic computerized book-entry changes in accounts of the participants, thereby eliminating the need for physical movement of securities certificates. Participants include securities brokers and dealers (including the underwriters), banks, trust companies, clearing corporations and certain other organizations, some of whom (and/or their representatives) own DTC. Access to DTC’s book-entry system is also available to others, such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly. Persons who are not participants may beneficially own securities held by DTC only through participants.

Unless and until it is exchanged in whole or in part for certificated debt securities in definitive form, a global note may not be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any such nominee to a successor depositary or a nominee of such successor depositary. The transferor shall provide or cause to be provided to the trustee all information necessary to allow the trustee to comply with any applicable tax reporting obligations, including without limitation any cost basis reporting obligations under Internal Revenue Code Section 6045. The trustee may rely on the information provided to it and shall have no responsibility to verify or ensure the accuracy of such information.

In connection with any proposed transfer outside the book entry-system, there shall be provided to the trustee all information necessary to allow the trustee to comply with any applicable tax reporting obligations, including without limitation any cost basis reporting obligations under Internal Revenue Code Section 6045. The trustee may rely on the information provided to it and shall have no responsibility to verify or ensure the accuracy of such information.

A further description of DTC’s procedures with respect to the notes is set forth in the accompanying prospectus under the heading “Description of Debt Securities and Related Guarantees—Transfer and Exchange.”

Clearstream. Clearstream Banking, société anonyme, or Clearstream, is incorporated under the laws of Luxembourg as a professional depositary. Clearstream holds securities for its participating organizations, or Clearstream Participants, and facilitates the clearance and settlement of securities transactions between Clearstream Participants through electronic book-entry changes in accounts of Clearstream Participants, thereby eliminating the need for physical movement of certificates. Clearstream provides Clearstream Participants with, among other things, services for safekeeping, administration, clearance and establishment of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic markets in several countries. As a professional depositary, Clearstream is subject to regulation by the Luxembourg Monetary Institute. Clearstream Participants are recognized financial institutions around the world, including underwriters, securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations, and may include the underwriters. Indirect access to Clearstream is also available to others, such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a Clearstream Participant either directly or indirectly.

Distributions with respect to the notes held beneficially through Clearstream will be credited to cash accounts of Clearstream Participants in accordance with its rules and procedures to the extent received by DTC for Clearstream.

Euroclear. The Euroclear System, or Euroclear, was created in 1968 to hold securities for participants of Euroclear, or Euroclear Participants, and to clear and settle transactions between Euroclear Participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. Euroclear includes various other services, including securities lending and borrowing and interfaces with domestic markets in several markets in several countries. Euroclear is operated by Euroclear Bank S.A./ N.V., or the Euroclear Operator, under contract with Euro-clear Clearance Systems S.C., a Belgian cooperative corporation, or the Cooperative. All operations are conducted by the Euroclear Operator, and all Euroclear securities clearance accounts and Euroclear cash accounts are accounts with the Euroclear Operator, not the Cooperative. The

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Cooperative establishes policy for Euroclear on behalf of Euroclear Participants. Euroclear Participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries and may include the underwriters. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear Participant, either directly or indirectly.

The Euroclear Operator is regulated and examined by the Belgian Banking Commission.

Links have been established among DTC, Clearstream and Euroclear to facilitate the initial issuance of the notes sold outside of the United States and cross-market transfers of the notes associated with secondary market trading.

Although DTC, Clearstream and Euroclear have agreed to the procedures provided below in order to facilitate transfers, they are under no obligation to perform these procedures, and these procedures may be modified or discontinued at any time.

Clearstream and Euroclear will record the ownership interests of their participants in much the same way as DTC, and DTC will record the total ownership of each of the U.S. agents of Clearstream and Euroclear, as participants in DTC. When the notes are to be transferred from the account of a DTC participant to the account of a Clearstream Participant or a Euroclear Participant, the purchaser must send instructions to Clearstream or Euroclear through a participant at least one day prior to settlement. Clearstream or Euroclear, as the case may be, will instruct its U.S. agent to receive the notes against payment. After settlement, Clearstream or Euroclear will credit the Clearstream Participant’s or Euroclear Participant’s account, as applicable. Credit for the notes will appear on the next day (European time).

Because settlement is taking place during New York business hours, DTC participants will be able to employ their usual procedures for sending the notes to the relevant U.S. agent acting for the benefit of Clearstream Participants or Euroclear Participants. The sale proceeds will be available to the DTC seller on the settlement date. As a result, to a DTC participant, a cross-market transaction will settle no differently than a trade between two DTC participants.

When a Clearstream Participant or Euroclear Participant wishes to transfer the notes to a DTC participant, the seller will be required to send instructions to Clearstream or Euroclear through a participant at least one business day prior to settlement. In these cases, Clearstream or Euroclear will instruct its U.S. agent to transfer these notes against payment for them. The payment will then be reflected in the account of the Clearstream or Euroclear Participant the following day, with the proceeds back valued to the value date, which would be the preceding day, when settlement occurs in New York. If settlement is not completed on the intended value date, that is, the trade fails, proceeds credited to the Clearstream or Euroclear Participant’s account will instead be valued as of the actual settlement date.

You should be aware that you will only be able to make and receive deliveries, payments and other communications involving the notes through Clearstream and Euroclear on the days when those clearing systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States. In addition, because of time zone differences there may be problems with completing transactions involving Clearstream and Euroclear on the same business day as in the United States.

Notices

Except as otherwise provided in the indenture, notices to holders of the notes will be given by mail to the addresses of holders of the notes as they appear in the note register; provided that notices given to holders holding the notes in book-entry form may be given through the facilities of DTC or any successor depository.

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Governing Law

The indenture, the notes and the guarantee will be governed by, and construed in accordance with, the law of the State of New York without regard to conflict of law principles that would result in the application of any law other than the law of the State of New York.

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UNDERWRITING (CONFLICTS OF INTEREST)

Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC, SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are acting as the book-running managers of the offering and as the representatives of the underwriters named below. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has severally agreed to purchase, and we have agreed to sell to that underwriter, the principal amount of the notes set forth opposite the underwriter’s name.

The underwriting agreement provides that the obligations of the underwriters to purchase the notes are subject to approval of legal matters by counsel and other conditions. The underwriters must purchase all the notes if they purchase any of the notes.

We have been advised by the representatives of the underwriters that the underwriters propose to offer the notes directly to the public at the public offering price set forth on the cover page of this prospectus supplement and may offer the notes to certain dealers at such price less a concession not in excess of     % of the principal amount of the notes. The underwriters may allow, and such dealers may re-allow, a concession not in excess of     % of the principal amount of the notes to certain other dealers. After the initial public offering, the representatives of the underwriters may change the offering price and other selling terms. This offering by the underwriters is subject to receipt and acceptance and subject to the underwriters’ right to reject any order in whole or in part.

The notes will constitute a new class of securities with no established trading market. We do not intend to list the notes on any national securities exchange or apply for quotation of the notes on any automated dealer quotation system. The underwriters have advised us that they currently intend to make a market in the notes.

However, they are not obligated to do so and they may discontinue any market-making activities with respect to the notes at any time without notice. We cannot assure you that the prices at which the notes will sell in the market after this offering will not be lower than the initial offering price or that an active trading market

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for the notes will develop and continue after this offering. Accordingly, we cannot assure you as to the liquidity of, or the trading market for, the notes.

We estimate that our portion of the total expenses of this offering will be $1.5 million. The following table shows the underwriters’ discounts that we are to pay to the underwriters in connection with this offering (expressed as a percentage of the principal amount of the notes).

In connection with the offering, the underwriters may purchase and sell notes in the open market. Purchases and sales in the open market may include short sales, purchases to cover short positions and stabilizing purchases.

Purchases to cover short positions and stabilizing purchases, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the market price of the notes. They may also cause the price of the notes to be higher than the price that would otherwise exist in the open market in the absence of these transactions. The underwriters may conduct these transactions in the over-the-counter market or otherwise. If the underwriters commence any of these transactions, they may discontinue them at any time.

Conflicts of Interest

In the ordinary course of their business, the underwriters or their respective affiliates have in the past performed, and may continue to perform, investment banking, broker dealer, financial advisory or other services for us, for which they received or may receive, customary fees and commissions.

In addition, affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC and U.S. Bancorp Investments, Inc. are lenders, affiliates of SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are co-documentation agents, affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC are syndication agents, Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC and affiliates of SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are joint lead arrangers and joint book running managers, and affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC are issuing banks under our operating partnership’s global revolving credit facility. Therefore, such underwriters and/or affiliates of such underwriters may receive more than 5% of the net proceeds from this offering through the repayment of the borrowings under the global revolving credit facility.

Affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC are syndication agents, Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC and affiliates of SMBC Nikko Securities America, Inc. and U.S. Bancorp Investments, Inc. are joint lead arrangers and joint book running managers, and affiliates of Merrill Lynch, Pierce, Fenner & Smith Incorporated, J.P. Morgan Securities LLC and U.S. Bancorp Investments, Inc. are lenders under our term loan facility.

Underwriters and their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own

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account and for the accounts of their customers. Such investment and securities activities may involve securities and/or instruments of ours or our affiliates. Of the underwriters (or their affiliates) that have lending relationships with us, certain of them routinely hedge and others may hedge their credit exposure to us consistent with their customary risk management policies. Typically, these underwriters and/or their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any such credit default swaps or short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Merrill Lynch, Pierce, Fenner & Smith Incorporated is a sales agent under our equity distribution agreements, pursuant to which we can issue and sell shares of our common stock having an aggregate offering price of up to $400.0 million from time to time through them. Certain underwriters and their affiliates in the past have leased, currently lease and in the future may lease space from us.

We have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the underwriters may be required to make because of any of those liabilities.

In connection with the offering, certain of the underwriters or securities dealers may distribute prospectuses by electronic means, such as e-mail.

Notice to Prospective Investors in the Dubai International Financial Centre

This prospectus supplement relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (“DFSA”). This prospectus supplement is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for this prospectus supplement. The notes to which this prospectus supplement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the notes offered should conduct their own due diligence on the notes. If you do not understand the contents of this prospectus supplement you should consult an authorized financial advisor.

Notice to Prospective Investors in the European Economic Area

The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the European Economic Area (“EEA”). For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, “MiFID II”); or (ii) a customer within the meaning of Directive 2002/92/EC (as amended, the “Insurance Mediation Directive”), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Directive 2003/71/EC (as amended, the “Prospectus Directive”) . Consequently, no key information document required by Regulation (EU) No 1286/2014 (as amended, the “PRIIPs Regulation”) for offering or selling the notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPS Regulation. This prospectus supplement and the accompanying prospectus have been prepared on the basis that any offer of the notes in any Member State of the EEA will be made pursuant to an exemption under the Prospectus Directive from the requirement to publish a prospectus for offers of the notes. This prospectus supplement and the accompanying prospectus are not a prospectus for the purposes of the Prospectus Directive.

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Notice to Prospective Investors in France

Neither this prospectus supplement nor any other offering material relating to the notes described in this prospectus supplement has been submitted to the clearance procedures of the Autorite des Marches Financiers or of the competent authority of another member state of the European Economic Area and notified to the Autorite des Marches Financiers. The notes have not been offered or sold and will not be offered or sold, directly or indirectly, to the public in France. Neither this prospectus supplement nor any other offering material relating to the notes has been or will be:

Such offers, sales and distributions will be made in France only:

The notes may be resold directly or indirectly, only in compliance with articles L.411-1, L.411-2, L.412-1 and L.621-8 through L.621-8-3 of the French Code monétaire etfinancier.

Notice to Prospective Investors in Germany

Any offer or solicitation of the notes within Germany must be in full compliance with the German Securities Prospectus Act Wertpapierprospektgesetz—WpPG. The offer and solicitation of the notes to the public in Germany requires the publication of a prospectus that has to be filed with and approved by the German Federal Financial Services Supervisory Authority Bundesanstalt fur Finanzdienstleistungsaufsicht—BaFin. This prospectus supplement has not been and will not be submitted for filing and approval to the BaFin and consequently will not be published. Therefore, this prospectus supplement does not constitute a public offer under the German Securities Prospectus Act Wertpapierprospektgesetz. This prospectus supplement and any other document relating to the notes as well as any information contained therein must therefore not be supplied to the public in Germany or used in connection with any offer for subscription of the notes to the public in Germany, any public marketing of the notes or any public solicitation for offers to subscribe for or otherwise acquire the notes. This prospectus supplement and other offering materials relating to the offer of the notes are strictly confidential and may not be distributed to any person or entity other than the designated recipients hereof.

Notice to Prospective Investors in Japan

This offering has not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948 of Japan, as amended) (the “FIEL”) and the initial purchaser will not offer or sell any notes, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIEL and any other applicable laws, regulations and ministerial guidelines of Japan.

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Notice to Prospective Investors in Hong Kong

The notes have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that Ordinance. No advertisement, invitation or document relating to the notes has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to the notes which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the Securities and Futures Ordinance and any rules made under that Ordinance.

Notice to Prospective Investors in the Republic of Korea

The notes have not been and will not be registered under the Financial Investment Services and Capital Markets Act and the decrees and regulations thereunder (the “FSCMA”) and the notes have been and will be offered in Korea as a private placement under the FSCMA. None of the notes may be offered, sold and delivered directly or indirectly, or offered or sold to any person for re-offering or resale, directly or indirectly, in Korea or to any resident of Korea except as otherwise permitted under the applicable laws and regulations of Korea, including the FSCMA and the Foreign Exchange Transaction Law of Korea and the decrees and regulations thereunder (the “FETL”). For a period of one year from the issue date of the notes, any acquirer of the notes who was solicited to buy the notes in Korea is prohibited from transferring any of the notes to another person in any way other than as a whole to one transferee. Furthermore, the purchaser of the notes shall comply with all applicable regulatory requirements (including but not limited to requirements under the FETL) in connection with the purchase of the notes.

Notice to Prospective Investors in the Netherlands

The notes may not, directly or indirectly, be offered or acquired in the Netherlands and this prospectus supplement may not be circulated in the Netherlands, as part of an initial distribution or any time thereafter, other than to individuals or (legal) entities who or which qualify as qualified investors within the meaning of Article 1:1 of the Financial Supervision Act (Wet op het financieel toezicht) as amended from time to time.

Notice to Prospective Investors in Singapore

This prospectus supplement has not been and will not be lodged or registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the notes may not be circulated or distributed, nor may the notes be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than: (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”); (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in Section 275, of the SFA; or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the notes are subscribed or purchased under Section 275 of the SFA by a relevant person which is: (a) a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (b) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor, securities (as defined in Section 239(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (howsoever

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described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the notes pursuant to an offer made under Section 275 of the SFA except: (i) to an institutional investor or to a relevant person defined in Section 275(2) of the SFA, or to any person arising from an offer referred to in Section 275(1A) or Section 276(4)(i)(B) of the SFA; (ii) where no consideration is or will be given for the transfer; (iii) where the transfer is by operation of law; (iv) as specified in Section 276(7) of the SFA; or (v) as specified in Regulation 32 of the Securities and Futures (Offers of Investments) (Shares and Debentures) Regulations 2005 of Singapore.

Notice to Prospective Investors in the Kingdom of Sweden

This prospectus supplement is not a prospectus and has not been prepared in accordance with the prospectus requirements laid down in the Swedish Financial Instruments Trading Act (lag (1991:980) om handel med finansiella instrument) nor any other Swedish enactment. Neither the Swedish Financial Supervisory Authority nor any other Swedish regulatory body has examined, approved or registered this prospectus supplement. No notes will be offered or sold to any investor in Sweden except in circumstances that will not result in a requirement to prepare a prospectus pursuant to the provisions of the Swedish Financial Instruments Trading Act.

Notice to Prospective Investors in Switzerland

This prospectus supplement, as well as any other material relating to the notes which are the subject of the offering contemplated by this prospectus supplement, do not constitute an issue prospectus pursuant to Article 652a and/or 1156 of the Swiss Code of Obligations. The notes will not be listed on the SIX Swiss Exchange and, therefore, the documents relating to the notes, including, but not limited to, this prospectus supplement, do not claim to comply with the disclosure standards of the listing rules of SIX Swiss Exchange and corresponding prospectus schemes annexed to the listing rules of the SIX Swiss Exchange. The notes may be offered in Switzerland by way of a private placement, i.e., to a small number of selected investors only, without any public offer and only to investors who do not purchase the notes with the intention to distribute them to the public. The investors may be individually approached by us from time to time. This prospectus supplement, as well as any other material relating to the notes, is personal and confidential and do not constitute an offer to any other person. This prospectus supplement may only be used by those investors to whom it has been handed out in connection with the offering described herein and may neither directly nor indirectly be distributed or made available to other persons without our express consent. It may not be used in connection with any other offer and shall in particular not be copied and/or distributed to the public in (or from) Switzerland.

Notice to Prospective Investors in the United Kingdom

This prospectus supplement and the accompanying prospectus are only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors within the meaning of Article 2(1)(e) of the Prospectus Directive that are also (i) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”) or (ii) high net worth entities, and other persons to whom it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order (each such person being referred to as a “relevant person”). This prospectus supplement and its contents are confidential and should not be distributed, published or reproduced (in whole or in part) or disclosed by recipients to any other persons in the United Kingdom. Any person in the United Kingdom that is not a relevant person should not act or rely on this document or any of its contents.

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SUPPLEMENTAL U.S. FEDERAL INCOME TAX CONSIDERATIONS

For a discussion of certain material United States federal income tax consequences regarding our company and holders of our operating partnership’s debt securities, please see Exhibit 99.1 to our Current Report on Form 8-K filed with the SEC on June 14, 2018 which was filed pursuant to Item 8.01 of Form 8-K. Such Form 8-K (including Exhibit 99.1 thereto) is incorporated by reference into the accompanying prospectus and supersedes and replaces, in its entirety, the discussion under the heading “United States Federal Income Tax Considerations” in the accompanying prospectus and in our registration statement on Form S-3 (File Nos. 333-220576 and 333-220576-01) filed with the SEC on September 22, 2017. Prospective investors in our operating partnership’s debt securities should consult their tax advisors regarding the United States federal income and other tax considerations to them of the acquisition, ownership and disposition of our operating partnership’s debt securities offered by this prospectus supplement.

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LEGAL MATTERS

Certain legal matters with respect to the validity of the notes will be passed upon for us by Latham & Watkins LLP, Los Angeles, California. Venable LLP, Baltimore, Maryland, will issue an opinion to us regarding certain matters of Maryland law. Certain legal matters will be passed upon for the underwriters by Goodwin Procter LLP, Boston, Massachusetts.

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EXPERTS

The consolidated financial statements and financial statement schedule III of Digital Realty Trust, Inc. and its subsidiaries as of December 31, 2017 and 2016 and for each of the years in the three-year period ended December 31, 2017 and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2017 have all been incorporated by reference in this prospectus supplement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The consolidated financial statements and financial statement schedule III of Digital Realty Trust, L.P. and its subsidiaries as of December 31, 2017 and 2016 and for each of the years in the three-year period ended December 31, 2017 have all been incorporated by reference in this prospectus supplement in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The audited historical financial statements of DuPont Fabros Technology, Inc. and DuPont Fabros Technology, L.P. included in Digital Realty Trust, Inc.’s and Digital Realty Trust, L.P.’s Current Reports on Form 8-K filed on July 10, 2017 and August 2, 2017, have been so incorporated in reliance on the report of Ernst & Young LLP, independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any document we file with the SEC at the SEC’s public reference rooms at 100 F Street, N.E. Room 1580, Washington, DC 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. The SEC also maintains a web site that contains reports, proxy and information statements, and other information regarding registrants that file electronically with the SEC at www.sec.gov. You can inspect reports and other information we file at the offices of the NYSE, 20 Broad Street, New York, New York 10005. In addition, we maintain a web site that contains information about us at www.digitalrealty.com. The information found on, or otherwise accessible through, our website is not incorporated into, and does not form a part of, this prospectus supplement, the accompanying prospectus or any other report or document we file with or furnish to the SEC.

We have filed with the SEC a registration statement on Form S-3 (File Nos. 333-220576 and 333-220576-01), of which this prospectus supplement and the accompanying prospectus are a part, including exhibits, schedules and amendments filed with, or incorporated by reference in, such registration statement, under the Securities Act. This prospectus supplement and the accompanying prospectus do not contain all of the information set forth in the registration statement and exhibits and schedules to the registration statement. For further information with respect to our company, reference is made to the registration statement, including the exhibits to the registration statement. Statements contained in this prospectus supplement and the accompanying prospectus as to the contents of any contract or other document referred to, or incorporated by reference, in this prospectus supplement and the accompanying prospectus are not necessarily complete and, where that contract or document is an exhibit to the registration statement, each statement is qualified in all respects by the exhibit to which the reference relates. Copies of the registration statement, including the exhibits and schedules to the registration statement, may be examined at the SEC’s public reference rooms at 100 F Street, N.E. Room 1580, Washington, DC 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. Copies of all or a portion of the registration statement can be obtained from the public reference rooms of the SEC upon payment of prescribed fees. The registration statement is also available to you on the SEC’s web site at www.sec.gov.

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INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” certain information we file with them which means that we can disclose important information to you by referring you to those documents instead of having to repeat the information in this prospectus supplement. The information incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference into this prospectus supplement and the accompanying prospectus the following documents (except for any document or portion thereof deemed to be “furnished” and not filed in accordance with SEC rules and regulations):

We will provide without charge to each person to whom a prospectus supplement is delivered, on written or oral request of that person, a copy of any or all of the documents we are incorporating by reference into this prospectus supplement, other than exhibits to those documents unless those exhibits are specifically incorporated by reference into those documents. A written request should be addressed to Investor Relations, Digital Realty Trust, Inc., Four Embarcadero Center, Suite 3200, San Francisco, California 94111.

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PROSPECTUS

Digital Realty Trust, Inc.

Common Stock, Preferred Stock, Depositary Shares, Warrants and Guarantees

Digital Realty Trust, L.P.

Debt Securities

We may from time to time offer, in one or more series or classes, separately or together, and in amounts, at prices and on terms to be set forth in one or more supplements to this prospectus, the following securities: (i) shares of Digital Realty Trust, Inc.’s common stock, par value $0.01 per share, (ii) shares of Digital Realty Trust, Inc.’s preferred stock, par value $0.01 per share, (iii) depositary shares representing entitlement to all rights and preferences of fractions of shares of Digital Realty Trust, Inc.’s preferred stock of a specified series and represented by depositary receipts, (iv) warrants to purchase shares of Digital Realty Trust, Inc.’s common stock or preferred stock or depositary shares and (v) debt securities of Digital Realty Trust, L.P. which may be fully and unconditionally guaranteed by Digital Realty Trust, Inc.

This prospectus also covers delayed delivery contracts that may be issued by Digital Realty Trust, Inc. or Digital Realty Trust, L.P. under which the counterparty may be required to purchase common stock, preferred stock, depositary shares or warrants to purchase common stock, preferred stock or depositary shares of Digital Realty Trust, Inc. or debt securities of Digital Realty Trust, L.P. (including guarantees of the debt securities by Digital Realty Trust, Inc.). Delayed delivery contracts may be issued together with the specific securities to which they relate. In addition, securities registered hereunder may be sold separately, together or as units with other securities registered hereunder.

We refer to the common stock, preferred stock, depositary shares, warrants and debt securities (together with any related guarantees) registered hereunder collectively as the “securities” in this prospectus. We will offer our securities in amounts, at prices and on terms determined at the time of the offering of any such security.

The specific terms of each series or class of the securities will be set forth in the applicable prospectus supplement and will include, as applicable: (i) in the case of common stock, any public offering price; (ii) in the case of preferred stock, the specific title and any dividend, liquidation, redemption, conversion, voting and other rights and any public offering price; (iii) in the case of depositary shares, the fractional share of preferred stock represented by each such depositary share; (iv) in the case of warrants, the duration, offering price, exercise price and detachability; and (v) in the case of debt securities and, as applicable, related guarantees, the specific terms of such debt securities and related guarantees. In addition, because Digital Realty Trust, Inc. is organized and conducts its operations so as to qualify as a real estate investment trust, or REIT, for U.S. federal income tax purposes, the specific terms of any securities may include limitations on actual or constructive ownership and restrictions on transfer of the securities, in each case as may be appropriate to preserve Digital Realty Trust, Inc.’s status as a REIT.

The securities may be offered directly by us, through agents designated from time to time by us, or to or through underwriters or dealers. These securities also may be offered by securityholders, if so provided in a prospectus supplement hereto. We will provide specific information about any selling securityholders in one or more supplements to this prospectus. If any agents, dealers or underwriters are involved in the sale of any of the securities, their names, and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections entitled “Plan of Distribution” and “About this Prospectus” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such series of securities.

Digital Realty Trust, Inc.’s common stock, series C preferred stock, series G preferred stock, series H preferred stock, series I preferred stock and series J preferred stock currently trade on the New York Stock Exchange, or NYSE, under the symbols “DLR”, “DLR Pr C”, “DLR Pr G”, “DLR Pr H”, “DLR Pr I” and “DLR Pr J”, respectively.

See “Risk Factors” beginning on page 3 for certain risk factors relevant to an investment in the securities.

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

The date of this prospectus is September 22, 2017.

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus to “we,” “us,” “our,” “our company” or “the company” refer to Digital Realty Trust, Inc., a Maryland corporation, together with its consolidated subsidiaries, including Digital Realty Trust, L.P., a Maryland limited partnership, of which Digital Realty Trust, Inc. is the sole general partner. Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus to “our operating partnership” or “the operating partnership” refer to Digital Realty Trust, L.P. together with its consolidated subsidiaries.

You should rely only on the information contained in this prospectus, in an accompanying prospectus supplement or incorporated by reference herein or therein. We have not authorized anyone to provide you with information or make any representation that is different. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the registered securities to which they relate, and this prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction where, or to any person to whom, it is unlawful to make such an offer or solicitation. You should not assume that the information contained in this prospectus and any accompanying prospectus supplement is correct on any date after the respective dates of this prospectus and such prospectus supplement or supplements, as applicable, even though this prospectus and such prospectus supplement or supplements are delivered or securities are sold pursuant to this prospectus and such prospectus supplement or supplements at a later date. Since the respective dates of the prospectus contained in this registration statement and any accompanying prospectus supplement, our business, financial condition, results of operations and prospects may have changed. We may only use this prospectus to sell the securities if it is accompanied by a prospectus supplement.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the United States Securities and Exchange Commission, or SEC, using a “shelf” registration process. Under this process, we may sell common stock, preferred stock, depositary shares, warrants and debt securities (and related guarantees, as applicable) in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement containing specific information about the terms of the applicable offering. Such prospectus supplement may add, update or change information contained in this prospectus. To the extent that this prospectus is used by any securityholder to resell any securities, information with respect to the securityholder and the terms of the securities being offered will be contained in a prospectus supplement. You should read this prospectus and the applicable prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”

We or any selling securityholders may offer the securities directly, through agents, or to or through underwriters. The applicable prospectus supplement will describe the terms of the plan of distribution and set forth the names of any agents or underwriters involved in the sale of the securities. See “Plan of Distribution” for more information on this topic. No securities may be sold without delivery of a prospectus supplement describing the method and terms of the offering of those securities.

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OUR COMPANY

We own, acquire, develop and operate data centers. We are focused on providing data center, colocation and interconnection solutions for domestic and international tenants across a variety of industry verticals ranging from financial services, cloud and information technology services, to manufacturing, energy, health care, and consumer products. Digital Realty Trust, L.P., a Maryland limited partnership, is the entity through which Digital Realty Trust, Inc., a Maryland corporation, conducts its business and owns its assets. Digital Realty Trust, Inc. operates as a REIT for U.S. federal income tax purposes.

We are diversified in major metropolitan areas where data center and technology tenants are concentrated, including the Atlanta, Boston, Chicago, Dallas, Los Angeles, New York, Northern Virginia, Phoenix, San Francisco, Seattle and Silicon Valley metropolitan areas in the United States, the Amsterdam, Dublin, Frankfurt, London and Paris metropolitan areas in Europe and the Singapore, Sydney, Melbourne, Hong Kong and Osaka metropolitan areas in the Asia Pacific region. The types of properties within our portfolio include:

Unlike traditional office and flex/research and development space, the location of and improvements to our facilities, including network density, interconnection infrastructure and connectivity-centric customers in certain of our facilities, are generally essential to our tenants’ businesses, which we believe results in high occupancy levels, longer average lease terms and customer relationships and lower turnover. In addition, many of our properties have tenant improvements that have been installed at our tenants’ expense. The tenant improvements in our facilities are generally readily adaptable for use by similar tenants.

Digital Realty Trust, Inc. was incorporated in the state of Maryland on March 9, 2004. Digital Realty Trust, L.P. was organized in the state of Maryland on July 21, 2004. Our principal executive offices are located at Four Embarcadero Center, Suite 3200, San Francisco, California 94111. Our telephone number at that location is (415) 738-6500. Our website is located at www.digitalrealty.com. The information found on, or otherwise accessible through, our website is not incorporated into, and does not form a part of, this prospectus or any other report or document we file with or furnish to the SEC.

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RISK FACTORS

Investment in any securities offered pursuant to this prospectus involves risks. Before acquiring any offered securities pursuant to this prospectus, you should carefully consider the information contained or incorporated by reference in this prospectus or in any accompanying prospectus supplement, including, without limitation, the risk factors incorporated by reference to the company’s and the operating partnership’s most recent combined Annual Report on Form 10-K, and the other information contained or incorporated by reference in this prospectus, as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended, or the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or a part of your investment in the offered securities. Please also refer to the section below entitled “Forward-Looking Statements.”

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any document we file with the SEC at the SEC’s public reference room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information about the public reference room. The SEC also maintains a web site that contains reports, proxy and information statements and other information regarding registrants that file electronically with the SEC at www.sec.gov. You can inspect reports and other information that Digital Realty Trust, Inc. files at the offices of the NYSE, 20 Broad Street, New York, New York 10005. In addition, we maintain a website that contains information about us at www.digitalrealty.com. The information found on, or otherwise accessible through, this website is not incorporated into, and does not form a part of, this prospectus or any other report or document we file with or furnish to the SEC.

We have filed with the SEC a registration statement on Form S-3, of which this prospectus is a part, including exhibits, schedules and amendments filed with, or incorporated by reference in, this registration statement, under the Securities Act of 1933, as amended, or the Securities Act, with respect to the securities registered hereby. This prospectus and any accompanying prospectus supplement do not contain all of the information set forth in the registration statement and exhibits and schedules to the registration statement. For further information with respect to our company and the securities registered hereby, reference is made to the registration statement, including the exhibits to the registration statement. Statements contained in this prospectus and any accompanying prospectus supplement as to the contents of any contract or other document referred to, or incorporated by reference in, this prospectus and any accompanying prospectus supplement are not necessarily complete and, where that contract is an exhibit to the registration statement, each statement is qualified in all respects by the exhibit to which the reference relates. Copies of the registration statement, including the exhibits and schedules to the registration statement, may be examined at the SEC’s public reference room. Copies of all or a portion of the registration statement can be obtained from the public reference room of the SEC upon payment of prescribed fees. This registration statement is also available to you on the SEC’s website.

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INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” in this prospectus the information we file with the SEC, which means that we can disclose important information to you by referring to those documents. The information incorporated by reference is an important part of this prospectus. The incorporated documents contain significant information about us, our business and our finances. Any statement contained in a document which is incorporated by reference in this prospectus is automatically updated and superseded if information contained in this prospectus, or information that we later file with the SEC, modifies or replaces this information. We incorporate by reference the following documents we filed with the SEC:

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We will provide without charge to each person, including any beneficial owner, to whom a prospectus is delivered, on written or oral request of that person, a copy of any or all of the documents we are incorporating by reference into this prospectus, other than exhibits to those documents unless those exhibits are specifically incorporated by reference into those documents. A written request should be addressed to Investor Relations, Digital Realty Trust, Inc., Four Embarcadero Center, Suite 3200, San Francisco, California 94111.

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FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains “forward-looking statements” within the meaning of the federal securities laws. Also, documents we subsequently file with the SEC and incorporate by reference will contain forward-looking statements. In particular, statements pertaining to our capital resources, portfolio performance and results of operations contain forward-looking statements. Likewise, all of our statements regarding anticipated market conditions, demographics and results of operations are forward-looking statements.

Forward-looking statements involve numerous risks and uncertainties and you should not rely on them as predictions of future events. Forward-looking statements depend on assumptions, data or methods which may be incorrect or imprecise and we may not be able to realize them. We do not guarantee that the transactions and events described will happen as described or that they will happen at all. You can identify forward-looking statements by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “seeks,” “approximately,” “intends,” “plans,” “pro forma,” “estimates” or “anticipates” or the negative of these words and phrases or similar words or phrases which are predictions of or indicate future events or trends and discussions which do not relate solely to historical matters. You can also identify forward-looking statements by discussions of strategy, plans or intentions. The following factors, among others, could cause actual results and future events to differ materially from those set forth or contemplated in the forward-looking statements:

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For a further discussion of these and other factors that could impact our future results, performance or transactions, see the section entitled “Risk Factors,” including the risks incorporated therein, from Digital Realty Trust, Inc.’s and Digital Realty Trust, L.P.’s most recent combined Annual Report on Form 10-K, as updated by our subsequent filings, including filings we make after the date of this prospectus. While forward-looking statements reflect our good faith beliefs, they are not guaranties of future performance. We disclaim any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors, new information, data or methods, future events or other changes.

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USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement, Digital Realty Trust, Inc. intends to contribute the net proceeds from any sale of common stock, preferred stock, depositary shares or warrants pursuant to this prospectus to our operating partnership. Unless otherwise indicated in the applicable prospectus supplement, our operating partnership intends to use such net proceeds received from Digital Realty Trust, Inc. and any net proceeds from any sale of debt securities pursuant to this prospectus for general corporate purposes, including, the repayment of outstanding indebtedness, the repurchase, redemption or retirement of outstanding debt or equity securities, and the funding of development and acquisition opportunities.

Pending application of cash proceeds, our operating partnership may use the net proceeds to temporarily reduce borrowings under our global revolving credit facility or we may invest the net proceeds in interest-bearing accounts and short-term, interest-bearing securities which are consistent with Digital Realty Trust, Inc.’s intention to qualify as a REIT for U.S. federal income tax purposes.

We will not receive any of the proceeds from sales of securities by selling securityholders, if any, pursuant to this prospectus.

Further details regarding the use of the net proceeds of a specific series or class of the securities will be set forth in the applicable prospectus supplement.

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RATIO OF EARNINGS TO FIXED CHARGES AND PREFERRED DIVIDENDS

Our ratios of earnings to fixed charges and earnings to fixed charges and preferred dividends for the periods indicated are as follows:

Digital Realty Trust, Inc.

Digital Realty Trust, Inc.’s ratios of earnings to fixed charges are computed by dividing earnings by fixed charges. Digital Realty Trust, Inc.’s ratios of earnings to fixed charges and preferred dividends are computed by dividing earnings by the sum of fixed charges and preferred dividends. For this purpose, “earnings” consist of income from continuing operations before noncontrolling interests and fixed charges. “Fixed charges” consist of interest expense, capitalized interest and amortization of deferred financing fees, whether expensed or capitalized, and interest within rental expense. “Preferred stock dividends” consist of the amount of pre-tax earnings required to pay dividends on Digital Realty Trust, Inc.’s series C convertible preferred stock (which was converted to common stock of Digital Realty Trust, Inc. on April 17, 2012), series D convertible preferred stock (which was converted to common stock on February 26, 2013), series E preferred stock (which was redeemed on September 15, 2016), series F preferred stock (which was redeemed on April 5, 2017), series G preferred stock, series H preferred stock and series I preferred stock.

Digital Realty Trust, L.P.

Digital Realty Trust, L.P.’s ratios of earnings to fixed charges are computed by dividing earnings by fixed charges. Digital Realty Trust, L.P.’s ratios of earnings to fixed charges and preferred unit distributions are computed by dividing earnings by the sum of fixed charges and preferred unit distributions. For this purpose, “earnings” consist of income from continuing operations before noncontrolling interests and fixed charges. “Fixed charges” consist of interest expense, capitalized interest and amortization of deferred financing fees, whether expensed or capitalized, and interest within rental expense. “Preferred unit distributions” consist of the amount of pre-tax earnings required to pay distributions on Digital Realty Trust, L.P.’s series C convertible preferred units (which were converted to common units of Digital Realty Trust, L.P. on April 17, 2012), series D convertible preferred units (which were converted to common units on February 26, 2013), series E preferred units (which were redeemed on September 15, 2016), series F preferred units (which were redeemed on April 5, 2017), series G preferred units, series H preferred units and series I preferred units.

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GENERAL DESCRIPTION OF SECURITIES

We or any selling securityholders named in a prospectus supplement directly or through agents, dealers or underwriters designated from time to time, may from time to time offer, issue and sell, together or separately, under this prospectus one or more of the following categories of securities:

We may issue Digital Realty Trust, L.P.’s debt securities, and related guarantees thereof by Digital Realty Trust, Inc., as exchangeable for and/or convertible into shares of Digital Realty Trust, Inc.’s common stock, preferred stock and/or other securities and related guarantees. Digital Realty Trust, Inc.’s preferred stock may also be exchangeable for and/or convertible into shares of its common stock, another series of its preferred stock, or its other securities. Digital Realty Trust, L.P.’s debt securities and related guarantees by Digital Realty Trust, Inc., and Digital Realty Trust, Inc.’s preferred stock, common stock, depositary shares and warrants are collectively referred to in this prospectus as the “securities.” When a particular series of securities is offered, a supplement to this prospectus will be delivered with this prospectus, which will set forth the terms of the offering and sale of the offered securities.

For purposes of the sections below entitled “Description of Common Stock,” “Description of Preferred Stock,” “Description of Depositary Shares,” “Description of Warrants,” and “Description of Debt Securities and Related Guarantees” references to “the company,” and “our company” refer only to Digital Realty Trust, Inc. and not to Digital Realty Trust, L.P. or its other subsidiaries.

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DESCRIPTION OF COMMON STOCK

The following description of Digital Realty Trust, Inc.’s common stock sets forth certain general terms and provisions of the common stock to which any prospectus supplement may relate and will apply to the common stock offered by this prospectus unless we provide otherwise in the applicable prospectus supplement. The description of Digital Realty Trust, Inc.’s common stock set forth below and in any prospectus supplement does not purport to be complete and is subject to and qualified in its entirety by reference to the applicable provisions of Digital Realty Trust, Inc.’s charter and bylaws.

General. The company’s charter provides that it may issue up to 315 million shares of its common stock, par value $0.01 per share, or the common stock. As of September 21, 2017, 205,164,931 shares of the common stock were issued and outstanding, excluding:

All outstanding shares of the common stock are duly authorized, fully paid and nonassessable. Subject to the preferential rights of any other class or series of stock and to the provisions of the company’s charter regarding the restrictions on transfer of stock, holders of shares of the common stock are entitled to receive dividends on such stock if, as and when authorized by the company’s board of directors out of assets legally available therefor and declared by the company and to share ratably in the assets of the company legally available for distribution to the company’s stockholders in the event of the company’s liquidation, dissolution or winding up after payment or establishment of reserves for all known debts and liabilities of the company.

Subject to the provisions of the company’s charter regarding the restrictions on transfer of stock and except as may be otherwise specified therein with respect to any class or series of common stock, each outstanding share of the common stock entitles the holder to one vote on all matters submitted to a vote of stockholders, including the election of directors and, except as provided with respect to any other class or series of stock, the holders of such shares will possess the exclusive voting power. There is no cumulative voting in the election of the company’s board of directors, which means that the holders of a majority of the outstanding shares of the common stock can elect all of the directors then standing for election and the holders of the remaining shares will not be able to elect any directors.

Holders of shares of the common stock have no preference, conversion, exchange, sinking fund or redemption rights, have no preemptive rights to subscribe for any securities of the company and generally have no appraisal

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rights unless the company’s board of directors determines that appraisal rights apply, with respect to all or any classes or series of stock, to one or more transactions occurring after the date of such determination in connection with which stockholders would otherwise be entitled to exercise appraisal rights. Subject to the provisions of the company’s charter regarding the restrictions on transfer of stock, shares of the common stock will have equal dividend, liquidation and other rights.

Under the Maryland General Corporation Law, or MGCL, a Maryland corporation generally cannot dissolve, amend its charter, merge, convert, sell all or substantially all of its assets, engage in a share exchange or engage in similar transactions outside the ordinary course of business unless the action is approved by the affirmative vote of stockholders entitled to cast at least two-thirds of the votes entitled to be cast on the matter unless a lesser percentage (but not less than a majority of all of the votes entitled to be cast on the matter) is set forth in the corporation’s charter. Except for certain charter amendments relating to the removal of directors and the vote required for certain amendments, the company’s charter provides that these actions may be taken if declared advisable by a majority of the company’s board of directors and approved by the vote of stockholders entitled to cast a majority of the votes entitled to be cast on the matter. However, Maryland law permits a corporation to transfer all or substantially all of its assets without the approval of the stockholders of the corporation to one or more persons if all of the equity interests of the person or persons are owned, directly or indirectly, by the corporation. In addition, operating assets may be held by a corporation’s subsidiaries, as in the company’s situation, and these subsidiaries may be able to transfer all or substantially all of such assets without a vote of the parent corporation’s stockholders.

The company’s charter authorizes its board of directors to reclassify any unissued shares of the common stock into other classes or series of stock and to establish the number of shares in each class or series and to set the preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications or terms or conditions of redemption for each such class or series.

Power to Increase Authorized Stock and Issue Additional Shares of the Common Stock

The company’s board of directors has the power to amend the company’s charter from time to time without stockholder approval to increase or decrease the number of authorized shares of common stock, to issue additional authorized but unissued shares of the common stock and to classify or reclassify unissued shares of the common stock into other classes or series of stock and thereafter to cause the company to issue such classified or reclassified shares of stock. The company believes these powers provide it with increased flexibility in structuring possible future financings and acquisitions and in meeting other needs which might arise. Subject to the limited rights of holders of the company’s series C preferred stock, series G preferred stock, series H preferred stock, series I preferred stock and series J preferred stock and each other parity class or series of preferred stock, voting together as a single class, to approve certain issuances of senior classes or series of stock, the additional classes or series, as well as the common stock, will be available for issuance without further action by the company’s stockholders, unless stockholder consent is required by applicable law or the rules of any stock exchange or automated quotation system on which the company’s securities may be listed or traded. Although the company’s board of directors does not intend to do so, it could authorize us to issue a class or series that could, depending upon the terms of the particular class or series, delay, defer or prevent a transaction or a change of control of the company that might involve a premium price for the company’s stockholders or otherwise be in their best interest.

Restrictions on Ownership and Transfer

To assist us in complying with certain U.S. federal income tax requirements applicable to REITs, the company has adopted certain restrictions relating to the ownership and transfer of the common stock. See “Restrictions on Ownership and Transfer.”

Transfer Agent and Registrar

The transfer agent and registrar for the common stock is American Stock Transfer & Trust Company, LLC.

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DESCRIPTION OF PREFERRED STOCK

The specific terms of a particular class or series of preferred stock will be described in the prospectus supplement relating to that class or series, including a prospectus supplement providing that preferred stock may be issuable upon the exercise of warrants the company issues. The description of preferred stock set forth below and the description of the terms of a particular class or series of preferred stock set forth in the applicable prospectus supplement do not purport to be complete and are qualified in their entirety by reference to the articles supplementary relating to that class or series.

General

The company’s charter provides that it may issue up to 110 million shares of preferred stock, $0.01 par value per share, or preferred stock. The company’s charter authorizes its board of directors to amend its charter from time to time without stockholder approval to increase the number of authorized shares of preferred stock. As of September 21, 2017, 8,050,000 shares of the company’s series C preferred stock, 10,000,000 shares of the company’s series G preferred stock, 14,600,000 shares of the company’s series H preferred stock, 10,000,000 shares of the company’s series I preferred stock and 8,000,000 shares of the company’s series J preferred stock were issued and outstanding. No other shares of the company’s preferred stock are currently outstanding.

The company’s charter authorizes its board of directors to classify any unissued shares of preferred stock and to reclassify any previously classified but unissued shares of any series into other classes or series of stock. Prior to the issuance of shares of each class or series, the company’s board of directors is required by the MGCL and the company’s charter to set, subject to the provisions of the company’s charter regarding the restrictions on transfers of stock, the terms, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications and terms or conditions of redemption for each such class or series. Thus, the company’s board of directors could authorize the issuance of shares of preferred stock with terms and conditions which could have the effect of delaying, deferring or preventing a transaction or a change of control of the company that might involve a premium price for holders of the common stock or otherwise be in their best interest.

The preferences and other terms of the preferred stock of each class or series will be fixed by the articles supplementary relating to such class or series. A prospectus supplement, relating to each class or series, will describe the terms of the preferred stock, including, where applicable, the following:

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Rank

Unless otherwise specified in the applicable prospectus supplement, the preferred stock will, with respect to dividend rights and rights upon liquidation, dissolution or winding up of the company, rank: (i) senior to all classes or series of the common stock, and to any other class or series of the company’s stock expressly designated as ranking junior to the preferred stock; (ii) on parity with any class or series of the company’s stock expressly designated as ranking on parity with the preferred stock; and (iii) junior to any other class or series of the company’s stock expressly designated as ranking senior to the preferred stock.

Conversion Rights

The terms and conditions, if any, upon which any shares of any class or series of preferred stock are convertible into the common stock will be described in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of the common stock into which the shares of preferred stock are convertible, the conversion price (or manner of calculation thereof), the conversion period, provisions as to whether conversion will be at the option of the holders of such class or series of preferred stock, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of such class or series of preferred stock.

Power to Increase Authorized Stock and Issue Additional Shares of Preferred Stock

The company’s board of directors has the power to amend the company’s charter from time to time without stockholder approval to increase the number of authorized shares of preferred stock, to issue additional authorized but unissued shares of the company’s preferred stock and to classify or reclassify unissued shares of the company’s preferred stock into other classes or series of stock and thereafter to cause us to issue such classified or reclassified shares of stock. Subject to the limited rights of holders of the company’s series C preferred stock, series G preferred stock, series H preferred stock, series I preferred stock and series J preferred stock and each other parity class or series of preferred stock, voting together as a single class, to approve certain issuances of senior classes or series of stock, the additional classes or series will be available for issuance without further action by the company’s stockholders, unless stockholder consent is required by applicable law or the rules of any stock exchange or automated quotation system on which the company’s securities may be listed or traded. Although the company’s board of directors does not intend to do so, it could authorize the company to issue a class or series that could, depending upon the terms of the particular class or series, delay, defer or prevent a transaction or a change of control of the company that might involve a premium price for the company’s stockholders or otherwise be in their best interest.

Restrictions on Ownership and Transfer

To assist the company in complying with certain U.S. federal income tax requirements applicable to REITs, the company has adopted certain restrictions relating to the ownership and transfer of the company’s series C

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preferred stock, series G preferred stock, series H preferred stock, series I preferred stock and series J preferred stock. The company expects to adopt similar restrictions with respect to any class or series offered pursuant to this prospectus under the articles supplementary for each such class or series. The applicable prospectus supplement will specify any additional ownership limitation relating to such class or series. See “Restrictions on Ownership and Transfer.”

6.625% Series C Cumulative Redeemable Perpetual Preferred Stock

General

The company’s board of directors approved articles supplementary, a copy of which has been previously filed with the SEC and which is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part, creating the series C preferred stock as a series of the company’s preferred stock, designated as the 6.625% Series C Cumulative Redeemable Perpetual Preferred Stock. The following description of the series C preferred stock is qualified in its entirety by reference to such articles supplementary and the company’s charter. The series C preferred stock is validly issued, fully paid and nonassessable

The series C preferred stock is currently listed on the NYSE as “DLR Pr C”.

Ranking

The series C preferred stock ranks, with respect to dividend rights and rights upon the company’s liquidation, dissolution or winding-up:

Dividend Rate and Payment Date

Holders are entitled to receive cumulative cash dividends on the series C preferred stock from and including the date of original issue, payable quarterly in arrears on or about the last calendar day of March, June, September and December of each year at the rate of 6.625% per annum of the $25.00 liquidation preference per share (equivalent to an annual amount of $1.65625 per share). Dividends on the series C preferred stock will accrue whether or not the company has earnings, whether or not there are funds legally available for the payment of such dividends and whether or not such dividends are authorized or declared.

Liquidation Preference

In the event of a liquidation, dissolution or winding up, holders of the series C preferred stock will have the right to receive $25.00 per share, plus accrued and unpaid dividends (whether or not earned or declared) up to but excluding the date of payment, before any payment is made to holders of the common stock and any other class or series of stock ranking junior to the series C preferred stock as to liquidation rights. The rights of holders of series C preferred stock to receive their liquidation preference will be subject to the proportionate rights of any other class or series of stock ranking on parity with the series C preferred stock as to liquidation.

Optional Redemption

The series C preferred stock may not be redeemed prior to May 15, 2021, except in limited circumstances to preserve the company’s status as a REIT and pursuant to the special optional redemption right described below.

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On and after May 15, 2021, the series C preferred stock will be redeemable at the company’s option, in whole or in part at any time or from time to time, for cash at a redemption price of $25.00 per share, plus accrued and unpaid dividends (whether or not authorized or declared) up to but excluding the redemption date. However, unless full cumulative dividends on the series C preferred stock for all past dividend periods have been, or contemporaneously are, paid or an amount in cash sufficient for the payment thereof is set apart, no shares of series C preferred stock may be redeemed; provided, that the foregoing restriction does not prevent DLR from taking action necessary to preserve its status as a REIT. Any partial redemption will be on a pro rata basis.

Special Optional Redemption

Upon the occurrence of a Change of Control, the company may, at its option, redeem the series C preferred stock, in whole or in part within 120 days after the first date on which such Change of Control occurred, by paying $25.00 per share, plus any accrued and unpaid dividends to, but not including, the date of redemption. If, prior to the Change of Control Conversion Date (as defined below), the company exercises any of its redemption rights relating to the series C preferred stock (whether its optional redemption right or its special optional redemption right), the holders of series C preferred stock will not have the conversion right described below.

A “Change of Control” is when, after the original issuance of the series G preferred stock, the following have occurred and are continuing:

No Maturity, Sinking Fund or Mandatory Redemption

The series C preferred stock has no stated maturity date and the company is not required to redeem the series C preferred stock at any time. Accordingly, the series C preferred stock will remain outstanding indefinitely, unless the company decides, at its option, to exercise its redemption right or, under circumstances where the holders of the series C preferred stock have a conversion right, such holders decide to convert the series C preferred stock into common stock. The series C preferred stock is not subject to any sinking fund.

Voting Rights

Holders of series C preferred stock generally have no voting rights. However, if the company is in arrears on dividends on the series C preferred stock for six or more quarterly periods, whether or not consecutive, holders of the series C preferred stock (voting together as a class with the holders of all other classes or series of parity preferred stock upon which like voting rights have been conferred and are exercisable) will be entitled to vote at a special meeting called upon the written request of at least 10% of such holders or at the next annual meeting of stockholders and each subsequent annual meeting of stockholders for the election of two additional directors to serve on the company’s board of directors until all accumulated dividends with respect to the series C preferred stock and any other class or series of parity preferred stock have been fully paid. In addition, the company may

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not make certain material and adverse changes to the terms of the series C preferred stock without the affirmative vote of the holders of at least two-thirds of the outstanding shares of series C preferred stock and all other shares of any class or series ranking on parity with the series C preferred stock that are entitled to similar voting rights (voting together as a single class).

Conversion

Upon the occurrence of a Change of Control, each holder of series C preferred stock will have the right (unless, prior to the Change of Control Conversion Date, the company has provided or provides notice of its election to redeem the series C preferred stock) to convert some or all of the series C preferred stock held by such holder on the date the series of C preferred stock is to be converted, which we refer to as the Change of Control Conversion Date, into a number of shares of common stock per share of series C preferred stock to be converted equal to the lesser of:

subject, in each case, to provisions for the receipt of alternative consideration as described in the articles supplementary relating to the series C preferred stock.

The “Common Stock Price” will be (i) if the consideration to be received in the Change of Control by the holders of common stock is solely cash, the amount of cash consideration per share of common stock, (ii) if the consideration to be received in the Change of Control by holders of common stock is other than solely cash, the average of the closing price per share of common stock on the ten consecutive trading days immediately preceding, but not including, the effective date of such Change of Control and (iii) if there is not a readily determinable closing price for the common stock, the fair market value of such other consideration received in the Change of Control per share of common stock as determined by the company’s board or a committee thereof.

If, prior to the Change of Control Conversion Date, the company has provided or provides a redemption notice, whether pursuant to its special optional redemption right in connection with a Change of Control or its optional redemption right, holders of series C preferred stock will not have any right to convert the series C preferred stock into shares of the company’s common stock in connection with the Change of Control and any shares of series C preferred stock selected for redemption that have been tendered for conversion will be redeemed on the related date of redemption instead of converted on the Change of Control Conversion Date.

Except as provided above in connection with a Change of Control, the series C preferred stock is not be convertible into or exchangeable for any other securities or property.

Transfer Agent and Registrar

The transfer agent and registrar for the series C preferred stock is American Stock Transfer & Trust Company, LLC. 

5.875% Series G Cumulative Redeemable Preferred Stock

General

The company’s board of directors and a duly authorized committee thereof approved articles supplementary, a copy of which has been previously filed with the SEC and which is incorporated by reference as an exhibit to the

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registration statement of which this prospectus is a part, creating the series G preferred stock as a series of the company’s preferred stock, designated as the 5.875% Series G Cumulative Redeemable Preferred Stock. The series G preferred stock is validly issued, fully paid and nonassessable.

The series G preferred stock is currently listed on the NYSE as “DLR Pr G”.

Ranking

The series G preferred stock ranks, with respect to dividend rights and rights upon the company’s liquidation, dissolution or winding-up:

Dividend Rate and Payment Date

Holders are entitled to receive cumulative cash dividends on the series G preferred stock from and including the date of original issue, payable quarterly in arrears on or about the last calendar day of March, June, September and December of each year, at the rate of 5.875% per annum of the $25.00 liquidation preference per share (equivalent to an annual amount of $1.46875 per share). Dividends on the series G preferred stock will accrue whether or not the company has earnings, whether or not there are funds legally available for the payment of such dividends and whether or not such dividends are authorized or declared.

Liquidation Preference

If the company liquidates, dissolves or winds up, holders of the series G preferred stock will have the right to receive $25.00 per share, plus accrued and unpaid dividends (whether or not earned or declared) up to but excluding the date of payment, before any payment is made to holders of the common stock and any other class or series of stock ranking junior to the series G preferred stock as to liquidation rights. The rights of holders of series G preferred stock to receive their liquidation preference will be subject to the proportionate rights of any other class or series of the company’s stock ranking on parity with the series G preferred stock as to liquidation.

Optional Redemption

The company may not redeem the series G preferred stock prior to April 9, 2018, except in limited circumstances to preserve the company’s status as a REIT and pursuant to the special optional redemption right described below. On and after April 9, 2018, the series G preferred stock will be redeemable at the company’s option, in whole or in part at any time or from time to time, for cash at a redemption price of $25.00 per share, plus accrued and unpaid dividends (whether or not authorized or declared) up to but excluding the redemption date. However, unless full cumulative dividends on the series G preferred stock for all past dividend periods have been, or contemporaneously are, paid or an amount in cash sufficient for the payment thereof is set apart by the company, no shares of series G preferred stock may be redeemed unless all outstanding shares of series G preferred stock are simultaneously redeemed; provided, that the foregoing restriction does not prevent the company from taking action necessary to preserve the company’s status as a REIT. Any partial redemption will be on a pro rata basis.

Special Optional Redemption

Upon the occurrence of a Change of Control (as defined below), the company may, at its option, redeem the series G preferred stock, in whole or in part within 120 days after the first date on which such Change of Control

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occurred, by paying $25.00 per share, plus any accrued and unpaid dividends to, but not including, the date of redemption. If, prior to the Change of Control Conversion Date (as defined below), the company exercises any of its redemption rights relating to the series G preferred stock (whether its optional redemption right or its special optional redemption right), the holders of series G preferred stock will not have the conversion right described below.

A “Change of Control” is when, after the original issuance of the series G preferred stock, the following have occurred and are continuing:

No Maturity, Sinking Fund or Mandatory Redemption

The series G preferred stock has no stated maturity date and the company is not required to redeem the series G preferred stock at any time. Accordingly, the series G preferred stock will remain outstanding indefinitely, unless the company decides, at its option, to exercise its redemption right or, under circumstances where the holders of the series G preferred stock have a conversion right, such holders decide to convert the series G preferred stock into the company’s common stock. The series G preferred stock is not subject to any sinking fund.

Voting Rights

Holders of series G preferred stock generally have no voting rights. However, if the company is in arrears on dividends on the series G preferred stock for six or more quarterly periods, whether or not consecutive, holders of the series G preferred stock (voting together as a class with the holders of all other classes or series of parity preferred stock upon which like voting rights have been conferred and are exercisable) will be entitled to vote at a special meeting called upon the written request of at least 10% of such holders or at the company’s next annual meeting and each subsequent annual meeting of stockholders for the election of two additional directors to serve on the company’s board of directors until all unpaid dividends with respect to the series G preferred stock and any other class or series of parity preferred stock have been paid or declared and a sum sufficient for the payment thereof set aside for payment. In addition, the company may not make certain material and adverse changes to the terms of the series G preferred stock without the affirmative vote of the holders of at least two-thirds of the outstanding shares of series G preferred stock and all other shares of any class or series ranking on parity with the series G preferred stock that are entitled to similar voting rights (voting together as a single class).

Conversion

Upon the occurrence of a Change of Control, each holder of series G preferred stock will have the right (unless, prior to the Change of Control Conversion Date, the company has provided or provides notice of its election to redeem the series G preferred stock) to convert some or all of the series G preferred stock held by such holder on the date the series of G preferred stock is to be converted, which we refer to as the Change of Control Conversion

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Date, into a number of shares of the company’s common stock per share of series G preferred stock to be converted equal to the lesser of:

subject, in each case, to provisions for the receipt of alternative consideration as described in the articles supplementary relating to the Series G preferred stock.

The “Common Stock Price” will be (i) if the consideration to be received in the Change of Control by the holders of the company’s common stock is solely cash, the amount of cash consideration per share of the company’s common stock or (ii) if the consideration to be received in the Change of Control by holders of the company’s common stock is other than solely cash (x) the average of the closing sale prices per share of the company’s common stock (or, if no closing sale price is reported, the average of the closing bid and ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control as reported on the principal U.S. securities exchange on which the company’s common stock is then traded, or (y) the average of the last quoted bid prices for the company’s common stock in the over-the-counter market as reported by Pink Sheets LLC or similar organization for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control, if the company’s common stock is not then listed for trading on a U.S. securities exchange.

If, prior to the Change of Control Conversion Date, the company has provided or provides a redemption notice, whether pursuant to its special optional redemption right in connection with a Change of Control or its optional redemption right, holders of series G preferred stock will not have any right to convert the series G preferred stock into shares of the company’s common stock in connection with the Change of Control and any shares of series G preferred stock selected for redemption that have been tendered for conversion will be redeemed on the related date of redemption instead of converted on the Change of Control Conversion Date.

Except as provided above in connection with a Change of Control, the series G preferred stock is not convertible into or exchangeable for any other securities or property.

Transfer Agent and Registrar

The transfer agent and registrar for the company’s series G preferred stock is American Stock Transfer & Trust Company, LLC.

7.375% Series H Cumulative Redeemable Preferred Stock

General

The company’s board of directors and a duly authorized committee thereof approved articles supplementary, a copy of which has been previously filed with the SEC and which is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part, creating the series H preferred stock as a series of the company’s preferred stock, designated as the 7.375% Series H Cumulative Redeemable Preferred Stock. The series H preferred stock is validly issued, fully paid and nonassessable.

The series H preferred stock is currently listed on the NYSE as “DLR Pr H”.

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Ranking

The series H preferred stock ranks, with respect to dividend rights and rights upon the company’s liquidation, dissolution or winding-up:

Dividend Rate and Payment Date

Holders are entitled to receive cumulative cash dividends on the series H preferred stock from and including the date of original issue, payable quarterly in arrears on or about the last calendar day of March, June, September and December of each year, at the rate of 7.375% per annum of the $25.00 liquidation preference per share (equivalent to an annual amount of $1.84375 per share). Dividends on the series H preferred stock will accrue whether or not the company has earnings, whether or not there are funds legally available for the payment of such dividends and whether or not such dividends are authorized or declared.

Liquidation Preference

If the company liquidates, dissolves or winds up, holders of the series H preferred stock will have the right to receive $25.00 per share, plus accrued and unpaid dividends (whether or not earned or declared) up to but excluding the date of payment, before any payment is made to holders of the common stock and any other class or series of stock ranking junior to the series H preferred stock as to liquidation rights. The rights of holders of series H preferred stock to receive their liquidation preference will be subject to the proportionate rights of any other class or series of the company’s stock ranking on parity with the series H preferred stock as to liquidation.

Optional Redemption

The company may not redeem the series H preferred stock prior to March 26, 2019, except in limited circumstances to preserve the company’s status as a REIT and pursuant to the special optional redemption right described below. On and after March 26, 2019, the series H preferred stock will be redeemable at the company’s option, in whole or in part at any time or from time to time, for cash at a redemption price of $25.00 per share, plus accrued and unpaid dividends (whether or not authorized or declared) up to but excluding the redemption date. However, unless full cumulative dividends on the series H preferred stock for all past dividend periods have been, or contemporaneously are, paid or an amount in cash sufficient for the payment thereof is set apart by the company, no shares of series H preferred stock may be redeemed unless all outstanding shares of series H preferred stock are simultaneously redeemed; provided, that the foregoing restriction does not prevent the company from taking action necessary to preserve the company’s status as a REIT. Any partial redemption will be on a pro rata basis.

Special Optional Redemption

Upon the occurrence of a Change of Control (as defined below), the company may, at its option, redeem the series H preferred stock, in whole or in part within 120 days after the first date on which such Change of Control occurred, by paying $25.00 per share, plus any accrued and unpaid dividends to, but not including, the date of redemption. If, prior to the Change of Control Conversion Date (as defined below), the company exercises any of its redemption rights relating to the series H preferred stock (whether its optional redemption right or its special optional redemption right), the holders of series H preferred stock will not have the conversion right described below.

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A “Change of Control” is when, after the original issuance of the series H preferred stock, the following have occurred and are continuing:

No Maturity, Sinking Fund or Mandatory Redemption

The series H preferred stock has no stated maturity date and the company is not required to redeem the series H preferred stock at any time. Accordingly, the series H preferred stock will remain outstanding indefinitely, unless the company decides, at its option, to exercise its redemption right or, under circumstances where the holders of the series H preferred stock have a conversion right, such holders decide to convert the series H preferred stock into the company’s common stock. The series H preferred stock is not subject to any sinking fund.

Voting Rights

Holders of series H preferred stock generally have no voting rights. However, if the company is in arrears on dividends on the series H preferred stock for six or more quarterly periods, whether or not consecutive, holders of the series H preferred stock (voting together as a class with the holders of all other classes or series of parity preferred stock upon which like voting rights have been conferred and are exercisable) will be entitled to vote at a special meeting called upon the written request of at least 10% of such holders or at the company’s next annual meeting and each subsequent annual meeting of stockholders for the election of two additional directors to serve on the company’s board of directors until all unpaid dividends with respect to the series H preferred stock and any other class or series of parity preferred stock have been paid or declared and a sum sufficient for the payment thereof set aside for payment. In addition, the company may not make certain material and adverse changes to the terms of the series H preferred stock without the affirmative vote of the holders of at least two-thirds of the outstanding shares of series H preferred stock and all other shares of any class or series ranking on parity with the series H preferred stock that are entitled to similar voting rights (voting together as a single class).

Conversion

Upon the occurrence of a Change of Control, each holder of series H preferred stock will have the right (unless, prior to the Change of Control Conversion Date, the company has provided or provides notice of its election to redeem the series H preferred stock) to convert some or all of the series H preferred stock held by such holder on the date the series of H preferred stock is to be converted, which we refer to as the Change of Control Conversion Date, into a number of shares of the company’s common stock per share of series H preferred stock to be converted equal to the lesser of:

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subject, in each case, to provisions for the receipt of alternative consideration as described in the articles supplementary relating to the Series H preferred stock.

The “Common Stock Price” will be (i) if the consideration to be received in the Change of Control by the holders of the company’s common stock is solely cash, the amount of cash consideration per share of the company’s common stock or (ii) if the consideration to be received in the Change of Control by holders of the company’s common stock is other than solely cash (x) the average of the closing sale prices per share of the company’s common stock (or, if no closing sale price is reported, the average of the closing bid and ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control as reported on the principal U.S. securities exchange on which the company’s common stock is then traded, or (y) the average of the last quoted bid prices for the company’s common stock in the over-the-counter market as reported by Pink Sheets LLC or similar organization for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control, if the company’s common stock is not then listed for trading on a U.S. securities exchange.

If, prior to the Change of Control Conversion Date, the company has provided or provides a redemption notice, whether pursuant to its special optional redemption right in connection with a Change of Control or its optional redemption right, holders of series H preferred stock will not have any right to convert the series H preferred stock into shares of the company’s common stock in connection with the Change of Control and any shares of series H preferred stock selected for redemption that have been tendered for conversion will be redeemed on the related date of redemption instead of converted on the Change of Control Conversion Date.

Except as provided above in connection with a Change of Control, the series H preferred stock is not convertible into or exchangeable for any other securities or property.

Transfer Agent and Registrar

The transfer agent and registrar for the company’s series H preferred stock is American Stock Transfer & Trust Company, LLC.

6.350% Series I Cumulative Redeemable Preferred Stock

General

The company’s board of directors and a duly authorized committee thereof approved articles supplementary, a copy of which has been previously filed with the SEC and which is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part, creating the series I preferred stock as a series of the company’s preferred stock, designated as the 6.350% Series I Cumulative Redeemable Preferred Stock. The series I preferred stock is validly issued, fully paid and nonassessable.

The series I preferred stock is currently listed on the NYSE as “DLR Pr I”.

Ranking

The series I preferred stock ranks, with respect to dividend rights and rights upon the company’s liquidation, dissolution or winding-up:

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Dividend Rate and Payment Date

Holders are entitled to receive cumulative cash dividends on the series I preferred stock from and including the date of original issue, payable quarterly in arrears on or about the last calendar day of March, June, September and December of each year, at the rate of 6.350% per annum of the $25.00 liquidation preference per share (equivalent to an annual amount of $1.5875 per share). Dividends on the series I preferred stock will accrue whether or not the company has earnings, whether or not there are funds legally available for the payment of such dividends and whether or not such dividends are authorized or declared.

Liquidation Preference

If the company liquidates, dissolves or winds up, holders of the series I preferred stock will have the right to receive $25.00 per share, plus accrued and unpaid dividends (whether or not earned or declared) up to but excluding the date of payment, before any payment is made to holders of the common stock and any other class or series of stock ranking junior to the series I preferred stock as to liquidation rights. The rights of holders of series I preferred stock to receive their liquidation preference will be subject to the proportionate rights of any other class or series of the company’s stock ranking on parity with the series I preferred stock as to liquidation.

Optional Redemption

The company may not redeem the series I preferred stock prior to August 24, 2020, except in limited circumstances to preserve the company’s status as a REIT and pursuant to the special optional redemption right described below. On and after August 24, 2020, the series I preferred stock will be redeemable at the company’s option, in whole or in part at any time or from time to time, for cash at a redemption price of $25.00 per share, plus accrued and unpaid dividends (whether or not authorized or declared) up to but excluding the redemption date. However, unless full cumulative dividends on the series I preferred stock for all past dividend periods have been, or contemporaneously are, paid or an amount in cash sufficient for the payment thereof is set apart by the company, no shares of series I preferred stock may be redeemed unless all outstanding shares of series I preferred stock are simultaneously redeemed; provided, that the foregoing restriction does not prevent the company from taking action necessary to preserve the company’s status as a REIT. Any partial redemption will be on a pro rata basis.

Special Optional Redemption

Upon the occurrence of a Change of Control (as defined below), the company may, at its option, redeem the series I preferred stock, in whole or in part within 120 days after the first date on which such Change of Control occurred, by paying $25.00 per share, plus any accrued and unpaid dividends to, but not including, the date of redemption. If, prior to the Change of Control Conversion Date (as defined below), the company exercises any of its redemption rights relating to the series I preferred stock (whether its optional redemption right or its special optional redemption right), the holders of series I preferred stock will not have the conversion right described below.

A “Change of Control” is when, after the original issuance of the series I preferred stock, the following have occurred and are continuing:

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No Maturity, Sinking Fund or Mandatory Redemption

The series I preferred stock has no stated maturity date and the company is not required to redeem the series I preferred stock at any time. Accordingly, the series I preferred stock will remain outstanding indefinitely, unless the company decides, at its option, to exercise its redemption right or, under circumstances where the holders of the series I preferred stock have a conversion right, such holders decide to convert the series I preferred stock into the company’s common stock. The series I preferred stock is not subject to any sinking fund.

Voting Rights

Holders of series I preferred stock generally have no voting rights. However, if the company is in arrears on dividends on the series I preferred stock for six or more quarterly periods, whether or not consecutive, holders of the series I preferred stock (voting together as a class with the holders of all other classes or series of parity preferred stock upon which like voting rights have been conferred and are exercisable) will be entitled to vote at a special meeting called upon the written request of at least 10% of such holders or at the company’s next annual meeting and each subsequent annual meeting of stockholders for the election of two additional directors to serve on the company’s board of directors until all unpaid dividends with respect to the series I preferred stock and any other class or series of parity preferred stock have been paid or declared and a sum sufficient for the payment thereof set aside for payment. In addition, the company may not make certain material and adverse changes to the terms of the series I preferred stock without the affirmative vote of the holders of at least two-thirds of the outstanding shares of series I preferred stock and all other shares of any class or series ranking on parity with the series I preferred stock that are entitled to similar voting rights (voting together as a single class).

Conversion

Upon the occurrence of a Change of Control, each holder of series I preferred stock will have the right (unless, prior to the Change of Control Conversion Date, the company has provided or provides notice of its election to redeem the series I preferred stock) to convert some or all of the series I preferred stock held by such holder on the date the series of I preferred stock is to be converted, which we refer to as the Change of Control Conversion Date, into a number of shares of the company’s common stock per share of series I preferred stock to be converted equal to the lesser of:

subject, in each case, to provisions for the receipt of alternative consideration as described in the articles supplementary relating to the Series I preferred stock.

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The “Common Stock Price” will be (i) if the consideration to be received in the Change of Control by the holders of the company’s common stock is solely cash, the amount of cash consideration per share of the company’s common stock or (ii) if the consideration to be received in the Change of Control by holders of the company’s common stock is other than solely cash (x) the average of the closing sale prices per share of the company’s common stock (or, if no closing sale price is reported, the average of the closing bid and ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control as reported on the principal U.S. securities exchange on which the company’s common stock is then traded, or (y) the average of the last quoted bid prices for the company’s common stock in the over-the-counter market as reported by Pink Sheets LLC or similar organization for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control, if the company’s common stock is not then listed for trading on a U.S. securities exchange.

If, prior to the Change of Control Conversion Date, the company has provided or provides a redemption notice, whether pursuant to its special optional redemption right in connection with a Change of Control or its optional redemption right, holders of series I preferred stock will not have any right to convert the series I preferred stock into shares of the company’s common stock in connection with the Change of Control and any shares of series I preferred stock selected for redemption that have been tendered for conversion will be redeemed on the related date of redemption instead of converted on the Change of Control Conversion Date.

Except as provided above in connection with a Change of Control, the series I preferred stock is not convertible into or exchangeable for any other securities or property.

Transfer Agent and Registrar

The transfer agent and registrar for the company’s series I preferred stock is American Stock Transfer & Trust Company, LLC.

5.250% Series J Cumulative Redeemable Preferred Stock

General

The company’s board of directors and a duly authorized committee thereof approved articles supplementary, a copy of which has been previously filed with the SEC and which is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part, creating the series J preferred stock as a series of the company’s preferred stock, designated as the 5.250% Series J Cumulative Redeemable Preferred Stock. The following description of the series J preferred stock is qualified in its entirety by reference to such articles supplementary and the company’s charter. The series J preferred stock is validly issued, fully paid and nonassessable.

The series J preferred stock is currently listed on the NYSE as “DLR Pr J”.

Ranking

The series J preferred stock ranks, with respect to dividend rights and rights upon the company’s liquidation, dissolution or winding-up:

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Dividend Rate and Payment Date

Holders are entitled to receive cumulative cash dividends on the series J preferred stock from and including the date of original issue, payable quarterly in arrears on or about the last calendar day of March, June, September and December of each year, at the rate of 5.250% per annum of the $25.00 liquidation preference per share (equivalent to an annual amount of $1.3125 per share). Dividends on the series J preferred stock will accrue whether or not DLR has earnings, whether or not there are funds legally available for the payment of such dividends and whether or not such dividends are authorized or declared.

Liquidation Preference

In the event of a liquidation, dissolution or winding up, holders of the series J preferred stock will have the right to receive $25.00 per share, plus accrued and unpaid dividends (whether or not earned or declared) up to but excluding the date of payment, before any payment is made to holders of the common stock and any other class or series of stock ranking junior to the series J preferred stock as to liquidation rights. The rights of holders of series J preferred stock to receive their liquidation preference will be subject to the proportionate rights of any other class or series of stock ranking on parity with the series J preferred stock as to liquidation.

Optional Redemption

The series J preferred stock may not be redeemed prior to August 7, 2022, except in limited circumstances to preserve the company’s status as a REIT and pursuant to the special optional redemption right described below. On and after August 7, 2022, the series J preferred stock will be redeemable at the company’s option, in whole or in part at any time or from time to time, for cash at a redemption price of $25.00 per share, plus accrued and unpaid dividends (whether or not authorized or declared) up to but excluding the redemption date. However, unless full cumulative dividends on the series J preferred stock for all past dividend periods have been, or contemporaneously are, paid or an amount in cash sufficient for the payment thereof is set apart, no shares of series J preferred stock may be redeemed unless all outstanding shares of series J preferred stock are simultaneously redeemed; provided, that the foregoing restriction does not prevent the company from taking action necessary to preserve its status as a REIT. Any partial redemption will be on a pro rata basis.

Special Optional Redemption

Upon the occurrence of a Change of Control, the company may, at its option, redeem the series J preferred stock, in whole or in part within 120 days after the first date on which such Change of Control occurred, by paying $25.00 per share, plus any accrued and unpaid dividends to, but not including, the date of redemption. If, prior to the Change of Control Conversion Date (as defined below), the company exercises any of its redemption rights relating to the series J preferred stock (whether its optional redemption right or its special optional redemption right), the holders of series J preferred stock will not have the conversion right described below.

A “Change of Control” is when, after the original issuance of the series I preferred stock, the following have occurred and are continuing:

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No Maturity, Sinking Fund or Mandatory Redemption

The series J preferred stock has no stated maturity date and the company is not required to redeem the series J preferred stock at any time. Accordingly, the series J preferred stock will remain outstanding indefinitely, unless the company decides, at its option, to exercise its redemption right or, under circumstances where the holders of the series J preferred stock have a conversion right, such holders decide to convert the series J preferred stock into common stock. The series J preferred stock is not subject to any sinking fund.

Voting Rights

Holders of series J preferred stock generally have no voting rights. However, if the company is in arrears on dividends on the series J preferred stock for six or more quarterly periods, whether or not consecutive, holders of the series J preferred stock (voting together as a class with the holders of all other classes or series of parity preferred stock upon which like voting rights have been conferred and are exercisable) will be entitled to vote at a special meeting called upon the written request of at least 10% of such holders or at the next annual meeting of stockholders and each subsequent annual meeting of stockholders for the election of two additional directors to serve on the company’s board of directors until all unpaid dividends with respect to the series J preferred stock and any other class or series of parity preferred stock have been paid or declared and a sum sufficient for the payment thereof set aside for payment. In addition, the company may not make certain material and adverse changes to the terms of the series J preferred stock without the affirmative vote of the holders of at least two-thirds of the outstanding shares of series J preferred stock and all other shares of any class or series ranking on parity with the series J preferred stock that are entitled to similar voting rights (voting together as a single class).

Conversion

Upon the occurrence of a Change of Control, each holder of series J preferred stock will have the right (unless, prior to the Change of Control Conversion Date, the company has provided or provides notice of its election to redeem the series J preferred stock) to convert some or all of the series J preferred stock held by such holder on the date the series of J preferred stock is to be converted, which we refer to as the Change of Control Conversion Date, into a number of shares of common stock per share of series J preferred stock to be converted equal to the lesser of:

subject, in each case, to provisions for the receipt of alternative consideration as described in the articles supplementary relating to the Series J preferred stock.

The “Common Stock Price” will be (i) if the consideration to be received in the Change of Control by the holders of common stock is solely cash, the amount of cash consideration per share of common stock or (ii) if the consideration to be received in the Change of Control by holders of common stock is other than solely cash (x) the average of the closing sale prices per share of the common stock (or, if no closing sale price is reported,

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the average of the closing bid and ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control as reported on the principal U.S. securities exchange on which the common stock is then traded, or (y) the average of the last quoted bid prices for the DLR’s common stock in the over-the-counter market as reported by Pink Sheets LLC or similar organization for the ten consecutive trading days immediately preceding, but not including, the effective date of the Change of Control, if the common stock is not then listed for trading on a U.S. securities exchange.

If, prior to the Change of Control Conversion Date, the company has provided or provides a redemption notice, whether pursuant to its special optional redemption right in connection with a Change of Control or its optional redemption right, holders of series J preferred stock will not have any right to convert the series J preferred stock into shares of the company’s common stock in connection with the Change of Control and any shares of series J preferred stock selected for redemption that have been tendered for conversion will be redeemed on the related date of redemption instead of converted on the Change of Control Conversion Date.

Except as provided above in connection with a Change of Control, the series J preferred stock is not convertible into or exchangeable for any other securities or property.

Transfer Agent and Registrar

The transfer agent and registrar for the series J preferred stock is American Stock Transfer & Trust Company, LLC.

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DESCRIPTION OF DEPOSITARY SHARES

The company may, at its option, elect to offer depositary shares rather than full shares of preferred stock. Each depositary share will represent ownership of and entitlement to all rights and preferences of a fraction of a share of preferred stock of a specified series (including dividend, voting, redemption and liquidation rights). The applicable fraction will be specified in a prospectus supplement. The shares of preferred stock represented by the depositary shares will be deposited with a depositary named in the applicable prospectus supplement, under a deposit agreement, among the company, the depositary and the holders of the certificates evidencing depositary shares, or depositary receipts. Depositary receipts will be delivered to those persons purchasing depositary shares in the offering. The depositary will be the transfer agent, registrar and dividend disbursing agent for the depositary shares. Holders of depositary receipts agree to be bound by the deposit agreement, which requires holders to take certain actions such as filing proof of residence and paying certain charges.

The summary of the terms of the depositary shares contained in this prospectus shall apply unless otherwise specified on a supplement to this prospectus. This summary, as modified by any supplement to this prospectus, does not purport to be complete and is subject to, and qualified in its entirety by, the provisions of the deposit agreement, the company’s charter and the form of articles supplementary for the applicable series of preferred stock.

Dividends

The depositary will distribute all cash dividends or other cash distributions received in respect of the series of preferred stock represented by the depositary shares to the record holders of depositary receipts in proportion to the number of depositary shares owned by such holders on the relevant record date, which will be the same date as the record date fixed by the company for the applicable series of preferred stock. The depositary, however, will distribute only such amount as can be distributed without attributing to any depositary share a fraction of one cent, and any balance not so distributed will be added to and treated as part of the next sum received by the depositary for distribution to record holders of depositary receipts then outstanding.

In the event of a distribution other than in cash, the depositary will distribute property received by it to the record holders of depositary receipts entitled thereto, in proportion, as nearly as may be practicable, to the number of depositary shares owned by such holders on the relevant record date, unless the depositary determines (after consultation with the company) that it is not feasible to make such distribution, in which case the depositary may (with the company’s approval) adopt any other method for such distribution as it deems equitable and appropriate, including the sale of such property (at such place or places and upon such terms as it may deem equitable and appropriate) and distribution of the net proceeds from such sale to such holders.

Liquidation Preference

In the event of the liquidation, dissolution or winding up of the affairs of the company, whether voluntary or involuntary, the holders of each depositary share will be entitled to the fraction of the liquidation preference accorded each share of the applicable series of preferred stock as set forth in the applicable prospectus supplement.

Redemption

If the series of preferred stock represented by the applicable series of depositary shares is redeemable, such depositary shares will be redeemed from the proceeds received by the depositary resulting from the redemption, in whole or in part, of preferred stock held by the depositary. Whenever the company redeems any preferred stock held by the depositary, the depositary will redeem as of the same redemption date the number of depositary shares representing the preferred stock so redeemed. The depositary will mail the notice of redemption promptly upon receipt of such notice from the company and not less than 30 nor more than 60 days prior to the date fixed for redemption of the preferred stock and the depositary shares to the record holders of the depositary receipts.

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Voting

Promptly upon receipt of notice of any meeting at which the holders of the series of preferred stock represented by the applicable series of depositary shares are entitled to vote, the depositary will mail the information contained in such notice of meeting to the record holders of the depositary receipts as of the record date for such meeting. Each such record holder of depositary receipts will be entitled to instruct the depositary as to the exercise of the voting rights pertaining to the number of shares of preferred stock represented by such record holder’s depositary shares. The depositary will endeavor, insofar as practicable, to vote such preferred stock represented by such depositary shares in accordance with such instructions, and the company will agree to take all action which may be deemed necessary by the depositary in order to enable the depositary to do so. The depositary will abstain from voting any of the preferred stock to the extent that it does not receive specific instructions from the holders of depositary receipts.

Withdrawal of Preferred Stock

Upon surrender of depositary receipts at the principal office of the depositary and payment of any unpaid amount due the depositary, and subject to the terms of the deposit agreement, the owner of the depositary shares evidenced thereby is entitled to delivery of the number of whole shares of preferred stock and all money and other property, if any, represented by such depositary shares. Partial shares of preferred stock will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred stock to be withdrawn, the depositary will deliver to such holder at the same time a new depositary receipt evidencing such excess number of depositary shares. Holders of preferred stock thus withdrawn will not thereafter be entitled to deposit such shares under the deposit agreement or to receive depositary receipts evidencing depositary shares therefor.

Amendment and Termination of Deposit Agreement

The form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may at any time and from time to time be amended by agreement between the company and the depositary. However, any amendment which materially and adversely alters the rights of the holders (other than any change in fees) of depositary shares will not be effective unless such amendment has been approved by at least a majority of the depositary shares then outstanding. No such amendment may impair the right, subject to the terms of the deposit agreement, of any owner of any depositary shares to surrender the depositary receipt evidencing such depositary shares with instructions to the depositary to deliver to the holder the preferred stock and all money and other property, if any, represented thereby, except in order to comply with mandatory provisions of applicable law.

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

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Charges of Depositary

The company will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. The company will pay charges of the depositary in connection with the initial deposit of the preferred stock and initial issuance of the depositary shares, and redemption of the preferred stock and all withdrawals of preferred stock by owners of depositary shares. Holders of depositary receipts will pay transfer, income and other taxes and governmental charges and certain other charges as are provided in the deposit agreement to be for their accounts. In certain circumstances, the depositary may refuse to transfer depositary shares, may withhold dividends and distributions and sell the depositary shares evidenced by such depositary receipt if such charges are not paid. The applicable prospectus supplement will include information with respect to fees and charges, if any, in connection with the deposit or substitution of the underlying securities, the receipt and distribution of dividends, the sale or exercise of rights, the withdrawal of the underlying security, and the transferring, splitting or grouping of receipts. The applicable prospectus supplement will also include information with respect to the right to collect the fees and charges, if any, against dividends received and deposited securities.

Miscellaneous

The depositary will forward to the holders of depositary receipts all notices, reports and proxy soliciting material from the company which are delivered to the depositary and which the company is required to furnish to the holders of the preferred stock. In addition, the depositary will make available for inspection by holders of depositary receipts at the principal office of the depositary, and at such other places as it may from time to time deem advisable, any notices, reports and proxy soliciting material received from the company which are received by the depositary as the holder of preferred stock. The applicable prospectus supplement will include information about the rights, if any, of holders of receipts to inspect the transfer books of the depositary and the list of holders of receipts.

Neither the depositary nor the company assumes any obligation or will be subject to any liability under the deposit agreement to holders of depositary receipts other than for its negligence or willful misconduct. Neither the depositary nor the company will be liable if it is prevented or delayed by law or any circumstance beyond its control in performing its obligations under the deposit agreement. The obligations of the company and the depositary under the deposit agreement will be limited to performance in good faith of their duties thereunder, and they will not be obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred stock unless satisfactory indemnity is furnished. The company and the depositary may rely on written advice of counsel or accountants, on information provided by holders of the depositary receipts or other persons believed in good faith to be competent to give such information and on documents believed to be genuine and to have been signed or presented by the proper party or parties.

In the event the depositary shall receive conflicting claims, requests or instructions from any holders of depositary receipts, on the one hand, and the company, on the other hand, the depositary shall be entitled to act on such claims, requests or instructions received from the company.

Resignation and Removal of Depositary

The depositary may resign at any time by delivering to us notice of its election to do so, and the company may at any time remove the depositary, any such resignation or removal to take effect upon the appointment of a successor depositary and its acceptance of such appointment. Such successor depositary must be appointed within 60 days after delivery of the notice for resignation or removal and must be a bank or trust company having its principal office in the United States and having a combined capital and surplus of at least $150,000,000.

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DESCRIPTION OF WARRANTS

The company may issue warrants for the purchase of the common stock, preferred stock or depositary shares of Digital Realty Trust, Inc., and may issue warrants independently or together with common stock, preferred stock, depositary shares or debt securities or attached to or separate from such securities. The company will issue each series of warrants under a separate warrant agreement, and may appoint a bank or trust company as warrant agent, all as specified in the applicable prospectus supplement. Any warrant agent will act solely as the company’s agent in connection with the warrants and will not act for or on behalf of warrant holders.

The following sets forth certain general terms and provisions of the warrants that may be offered under this registration statement. Further terms of the warrants and applicable warrant agreements will be set forth in the applicable prospectus supplement.

The applicable prospectus supplement will describe the terms of the warrants in respect of which this prospectus is being delivered, including, where applicable, the following:

Warrant certificates will be exchangeable for new warrant certificates of different denominations and warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise or to any dividend payments or voting rights, as applicable, as to which holders of the shares of the common stock or preferred stock purchasable upon such exercise may be entitled.

Each warrant will entitle the holder to purchase for cash such number of shares of common stock, shares of preferred stock, or depository shares, at such exercise price as shall, in each case, be set forth, or be determinable as set forth, in the applicable prospectus supplement relating to the warrants offered thereby. Unless otherwise specified in the applicable prospectus supplement, warrants may be exercised at any time up to 5:00 p.m. New York City time on the expiration date set forth in applicable prospectus supplement. After 5:00 p.m. New York City time on the expiration date, unexercised warrants will be void.

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Warrants may be exercised as set forth in the applicable prospectus supplement relating to the warrants. Upon receipt of payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, the company will, as soon as practicable, forward the securities purchasable upon such exercise. If less than all of the warrants are presented by such warrant certificate of exercise, a new warrant certificate will be issued for the remaining amount of warrants.

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DESCRIPTION OF DEBT SECURITIES AND RELATED GUARANTEES

The following is a description of the general terms and provisions of our operating partnership’s debt securities and related guarantees by Digital Realty Trust, Inc., if applicable. When our operating partnership offers to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus, including the terms of any related guarantees by Digital Realty Trust, Inc. and the terms, if any, on which a series of debt securities may be convertible into or exchangeable for other securities. We will also indicate in the prospectus supplement whether the general terms and provisions described in this prospectus apply to a particular series of debt securities. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

The debt securities may be offered in the form of either senior debt securities or subordinated debt securities. Unless otherwise specified in a prospectus supplement, the debt securities will be the direct, unsecured obligations of Digital Realty Trust, L.P., and will rank equally in right of payment with all of Digital Realty Trust, L.P.’s other unsecured and unsubordinated indebtedness. The debt securities that are sold may be exchangeable for and/or convertible into common stock or any of the other securities that may be sold under this prospectus.

Unless otherwise specified in a prospectus supplement, the debt securities will be issued under an indenture between us and Wells Fargo Bank, National Association, as trustee, or the trustee. We have summarized select portions of the indenture below. The summary is not complete. We have filed the indenture as an exhibit to the registration statement of which this prospectus is a part, and you should read the indenture and our debt securities carefully for provisions that may be important to you. Capitalized terms used in the summary and not defined in this prospectus have the meaning specified in the indenture.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of the company’s board of directors and set forth or determined in the manner provided in an officer’s certificate or by a supplemental indenture. The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series, including any pricing supplement.

Unless otherwise specified in a prospectus supplement, the indenture will designate Wells Fargo Bank, National Association as the trustee for the indenture with respect to one or more series of our operating partnership’s debt securities and related guarantees of our company, if applicable. Wells Fargo Bank, National Association, or any other specified trustee, may resign or be removed with respect to one or more series of our debt securities, and a successor trustee may be appointed to act with respect to that series.

Unless otherwise specified in a supplement to this prospectus, the debt securities will be our operating partnership’s direct, unsecured obligations and will rank equally with all of its other unsecured and unsubordinated indebtedness, and may be fully and unconditionally guaranteed by the company. We can issue an unlimited amount of our operating partnership’s debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will set forth in a prospectus supplement, including any pricing supplement, relating to any series of debt securities being offered, the aggregate principal amount and the following terms of such series of debt securities, to the extent applicable:

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