More than 17,000 people have signed up to join an Austrian law students class action against Facebook over the social media groups alleged violations of its users privacy, the student said on Tuesday. Max Schrems, 26, appealed last week to a billion Facebook users to join a claim he filed at Viennas commercial court as part of his campaign. Under Austrian law, a group of people may transfer their financial claims to a single person – in this case, Schrems. Legal proceedings are then effectively run as a class action.