As a competitive strategy to lower costs and increase efficiency, banks often outsource their data service units to ad hoc data processing companies. The VAT exemption of these companies is a decisive factor in the economic viability of the outsourcing strategy. This article tackles the issue of the application of the exemption of Art. 13 (B) (d) of the Sixth Directive to data processing centres in the light of the decisions of the European Court of Justice and national courts.