The Federation of German Consumer Organizations said today it has sent a cease-and-desist letter to Facebook's European headquarters in Ireland.
The letter cites 19 clauses in the company's terms of service and data protection guidelines that the consumer groups claim breach German law.
German Justice Minister Heiko Maas backed the complaint, saying Facebook's data protection rules are too vague. He said users should be able to opt out of certain requirements without having to quit Facebook entirely.
The California-based company has faced regular legal challenges from privacy advocates in Europe.