The News Minute | September 2, 2014 | 11:26 am ISTLondon: In a bid to understand what separates a social network from a messaging application, European Union (EU) anti-trust officials have sent a detailed questionnaire to the competitors as well as customers of Facebook and WhatsApp.The move is part of the EU's formal review of the $19 billion acquisition of the popular mobile messaging service WhatsApp by the social network earlier this year, Wall Street Journal (WSJ) reported.The unusual 70-page questionnaire comes after Facebook and WhatsApp formally notified the EU antitrust body of the deal Aug 29.Europe's telecom industry argues that "over-the-top" operators such as WhatsApp use telecom companies' infrastructure but are not taxed or regulated in the same way.Some European politicians also have expressed deep concern in recent months at the way US technology companies have come to dominate Europe's digital economy, the WSJ report added.Recipients of the questionnaire are telecommunications operators, social-networking sites and other internet service providers.The provisional deadline for a decision in the case is Oct 3.With IANS