UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 12, 2012

DIGITAL REALTY TRUST, INC.

DIGITAL REALTY TRUST, L.P.

(Exact name of registrant as specified in its charter)

(415) 738-6500

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

The information in this Current Report on Form 8-K is furnished pursuant to Item 7.01 and shall not be deemed “filed” for any purpose, including for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section. The information in this Current Report on Form 8-K shall not be deemed incorporated by reference into any filing of Digital Realty Trust, Inc. (the company) or Digital Realty Trust, L.P. (our operating partnership) under the Securities Act of 1933, as amended, regardless of any general incorporation language in such filing.

On or around December 12, 2012, we will distribute a Notice of Adjustment to Exchange Rate to the holders of our operating partnership’s 5.50% Exchangeable Senior Debentures due 2029. The form of notice is attached as Exhibit 99.1 to this report.

As of December 12, 2012, the conversion rate on the company’s convertible preferred stock and exchange rate on our operating partnership’s exchangeable senior debentures are as follows:

(d) Exhibits.

Forward-Looking Statements

This report contains forward-looking statements which are based on current expectations, forecasts and assumptions that involve risks and uncertainties that could cause actual outcomes and results to differ materially, including statements related to expected dividend payments. These risks and uncertainties include, among others, the following: the impact of the recent deterioration in global economic, credit and market conditions, including the downgrade of the U.S. government’s credit rating; current local economic conditions in our geographic markets; decreases in information technology spending, including as a result of economic slowdowns or recession; adverse economic or real estate developments in our industry or the industry sectors that we sell to (including risks relating to decreasing real estate valuations and impairment charges); our dependence upon significant tenants; bankruptcy or insolvency of a major tenant or a significant number of smaller tenants; defaults on or non-renewal of leases by tenants; our failure to obtain necessary debt and equity financing; increased interest rates and operating costs; risks associated with using debt to fund our business activities, including re-financing and interest rate risks, our failure to repay debt when due, adverse changes in our credit ratings or our breach of covenants or other terms contained in our loan facilities and agreements; financial market fluctuations; changes in foreign currency exchange rates; our inability to manage our growth effectively; difficulty acquiring or operating properties in foreign jurisdictions; our failure to successfully integrate and operate acquired or redeveloped properties or businesses; risks related to joint venture investments, including as a result of our lack of control of such investments; delays or unexpected costs in development or redevelopment of properties; decreased rental rates or increased vacancy rates; increased competition or available supply of data center space; our inability to successfully develop and lease new properties and space held for redevelopment; difficulties in identifying properties to acquire and completing acquisitions; our inability to acquire off-market properties; our inability to comply with the rules and regulations applicable to reporting companies; the company’s failure to maintain its status as a REIT; possible adverse changes to tax laws; restrictions on our ability to engage in certain business activities; environmental uncertainties and risks related to natural disasters; losses in excess of our insurance coverage; changes in foreign laws and regulations, including those related to taxation and real estate ownership and operation; and changes in local, state and federal regulatory requirements, including changes in real estate and zoning laws and increases in real property tax rates. For a further list and description of such risks and uncertainties, see the reports and other filings by the company and our operating partnership with the U.S. Securities and Exchange Commission, including our combined Annual Report on Form 10-K for the year ended December 31, 2011 and Quarterly Reports on Form 10-Q for the quarters ended March 31, 2012, June 30, 2012 and September 30, 2012. We disclaim any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrants have duly caused this report to be signed on their behalf by the undersigned hereunto duly authorized.

Date: December 12, 2012

EXHIBITS