Facebook founder and chief executive Mark Zuckerberg has been threatened with a £16,000 fine if he does not allow Germans anonymous accounts on the social networking site.
A German state data protection agency has already sent letter to Zuckerberg in California and Facebook Ireland Ltd stating that the current terms of service for Facebook, which require users to provide their identities, violate German law.
Thilo Weichert, data protection commissioner for Schleswig-Holstein, said: "It is unacceptable that a US portal like Facebook violates German data protection law, unopposed and with no prospect of an end."
Under German law, media services, including Facebook, must offer users the choice of using a pseudonym.
However, speaking to the Guardian, data protection experts said they thought it was unlikely that Facebook would comply with the latest attempt to force the site into line with German law.
"I think it is not very likely Facebook will change its business model for one country, or even just one region in Germany," said Jörg Hladjk, a lawyer specialising in data protection at Hunton & Williams in Brussels. "Just from a business perspective, this does not make a lot of sense."
A Facebook spokesman said the orders were without merit and a waste of German taxpayers' money and that the company would fight vigorously.