Filed by InterXion Holding N.V.
Pursuant to Rule 425 under the Securities Act of 1933
Subject Company: InterXion Holding N.V.
Filer’s SEC File No.:001-35053

Press release 18 February 2020
Glass Lewis Joins Other Leading Independent Proxy Advisory Firm ISS in Recommending InterXion Shareholders Vote “FOR” All Proposals Related to ProposedStock-for-Stock Combination with Digital Realty
InterXion Urges Shareholders to Vote “FOR” All Merger-Related Proposals Today
AMSTERDAM – 18 February 2020— InterXion Holding N.V. (NYSE: INXN), a leading European provider of carrier and cloud-neutral colocation data centre services, today announced that leading independent proxy advisory firm, Glass Lewis & Co. (“Glass Lewis”), joined Institutional Shareholder Services (“ISS”) in recommending that InterXion shareholders vote “FOR” all proposals related to the Company’s proposed strategicstock-for-stock combination with Digital Realty Trust, Inc. (NYSE: DLR) at the Extraordinary General Meeting of InterXion (the “EGM”) scheduled for 27 February 2020.
In recommending that InterXion shareholders vote “FOR” all proposals to be presented at the EGM, Glass Lewis noted in its report dated 14 February 2020, “Overall, we find that the proposed transaction appears strategically compelling and financially reasonable to both InterXion and Digital Realty.1”
Commenting on the report, David Ruberg, InterXion’s Chief Executive Officer, said, “We are pleased that Glass Lewis has joined ISS in recommending that shareholders vote ‘FOR’ all shareholder proposals relating to our proposed combination with Digital Realty. We are confident that this is the right transaction, at the right time with the right partner. The InterXion Board recommends that shareholders vote ‘FOR’ all proposals at our upcoming EGM to enable the process and exchange offer to proceed.”
At the EGM, InterXion shareholders will consider proposals related to the reorganization of InterXion following completion of Digital Realty’s exchange offer for InterXion shares.