This Report on Form 6-K is being filed in connection with the
consummation of the transactions contemplated by that certain Purchase Agreement, dated as of October 29, 2019, as amended on January 23, 2020 (the Purchase Agreement), by and among Digital Realty Trust, Inc., a Maryland
Corporation (DLR), Digital Intrepid Holding B.V. (formerly known as DN 39J 7A B.V.), a private limited liability company organized under the laws of the Netherlands and an indirect subsidiary of DLR (Buyer), and InterXion
Holding N.V., a public limited liability company organized under the laws of the Netherlands (INXN). Pursuant to the Purchase Agreement, Buyer commenced an exchange offer (the Exchange Offer) to purchase all of the
outstanding ordinary shares of INXN, nominal value 0.10 per share (INXN Shares), in exchange for 0.7067 shares of common stock of DLR, par value $0.01 per share (DLR Common Stock), per INXN Share (the Offer
Consideration). Following the completion of the Exchange Offer, DLR, Buyer and INXN initiated the Post-Offer Reorganization (as defined in the Purchase Agreement). As part of the Post-Offer Reorganization, the Legal Merger and the Post-Merger
Share Sale have been implemented and the Liquidation and Second Step Distribution have been initiated (all pursuant to, and as defined in, the Purchase Agreement). Upon the consummation of the Exchange Offer, the Post-Offer Reorganization and the
other transactions contemplated by the Purchase Agreement, INXN merged with and into InterXion II B.V. (formerly known as Intrepid II B.V.), a private limited liability company organized under the laws of the Netherlands and an indirect subsidiary
of Buyer (InterXion II), and DLR has become the indirect owner of all of INXNs business operations. The following events took place in connection with the consummation of the transactions contemplated by the Purchase Agreement.
Completion of Acquisition or Disposition of Assets
At 12:01 a.m. (New York City time), on March 9, 2020, the Exchange Offer expired as scheduled and was not extended. Buyer was advised by American Stock
Transfer & Company, LLC (AST), the exchange agent for the Exchange Offer, that, as of the expiration of the initial offering period, a total of 64,732,624 INXN Shares, collectively representing approximately 83.3% of INXNs
outstanding capital on a fully diluted and as-converted basis, were validly tendered and not properly withdrawn in the Exchange Offer. Following the expiration of the initial offering period, DLR and Buyer
provided a subsequent offering period of three business days, which commenced on March 9, 2020 and expired at 12:01 a.m. (New York City time) on March 12, 2020. INXN shareholders who did not tender their INXN Shares during the initial
offering period were able to tender their INXN Shares any time prior to the expiration of the subsequent offering period. Buyer was advised by AST, that, as of the expiration of the subsequent offering period, a total of 70,862,736 INXN Shares,
collectively representing approximately 92.3% of INXNs issued and outstanding capital, were validly tendered and not properly withdrawn in the Exchange Offer. All conditions to the Exchange Offer having been satisfied, Buyer accepted for
exchange all of INXN Shares validly tendered during the initial offering period and the subsequent offering period.
Following the acceptance of INXN
Shares tendered in the Exchange Offer, on March 12, 2020, DLR, Buyer and INXN effectuated the Legal Merger (as defined in the Purchase Agreement) to initiate the Post-Offer Reorganization pursuant to the terms of the Purchase Agreement and as
further described below. As a result of the completion of the Post-Offer Reorganization, INXN merged with and into InterXion II and DLR has become the indirect owner of all of INXNs business operations.
At the time of the completion of the Exchange Offer, subject to applicable withholding taxes (if any): (1) (i) each then-outstanding INXN restricted share
award held by a non-employee member of the board of directors of INXN was cancelled and converted into the unrestricted right to receive the Offer Consideration, including any Fractional Share Cash Amount (as
defined in the Purchase Agreement), and (ii) each INXN restricted share award that was outstanding as of immediately prior to the completion of the Exchange Offer and that was held by a person other than a
non-employee member of the board of directors of INXN was assumed by DLR and converted into a number of restricted stock units covering shares of DLR Common Stock (DLR RSUs) (rounded to the nearest
whole DLR RSU) equal to the product of (x) the total number of INXN restricted shares subject to such award and (y) 0.7067; (2) (i) each outstanding award of INXN performance shares was deemed to have satisfied the performance condition
applicable thereto as follows: (A) with respect to INXN performance share awards subject to a performance period that has been completed prior to the completion of the Exchange Offer, at actual performance attained for such performance period
and (B) with respect to INXN performance share awards subject to a performance period that has not been completed as of the completion of the Exchange Offer, (x) for awards granted on or prior to October 29, 2019, at 150% of target
and (y) for awards granted after October 29, 2019, with respect to awards of performance shares held by members of INXNs senior management team other than David C. Ruberg, the executive director of INXN, at 115% of target or, with
respect to the awards of performance shares held by the executive director of INXN, at 100% of target; and (ii) each such performance share with performance levels