A German privacy watchdog this week ordered Facebook to allow users to join the social network with pseudonyms, Reuters reports, directly challenging the company's "authentic name" policy. In a decision handed down Tuesday, the Hamburg data protection authority said Facebook's name policy violates German privacy laws, adding that the company cannot force users to submit photo identification or change their profile names without their consent.

Facebook has come under increased criticism for its real name policy, with users complaining of having their accounts blocked or their names unilaterally changed. The company clarified its policy in March, saying that users are free to choose their "authentic identity" — the name they go by in real life, which may not be the name that appears on their official ID.

"If you like our game, you must play by our rules."

But Facebook still requires users to confirm their names with accepted forms of identification, which Germany's watchdog considers a violation of privacy. In the Hamburg case, a woman who tried to use a Facebook under an alias filed a complaint after the company blocked her account and requested a copy of her ID, before changing her name without her permission.

Facebook's privacy policy has come under fire from regulators across Europe, though the company has long argued that it should only be held to privacy laws in Ireland, where its European operations are headquartered. Johannes Caspar, Hamburg commissioner for data protection and freedom of information, rejected that argument this week, saying: "Facebook has economic activity in Germany with its branch in Hamburg. So: if you like our game, you must play by our rules."

Facebook defended its policy in a statement following the Hamburg decision, saying it enhances safety and transparency. "We’re disappointed Facebook’s authentic name policy is being revisited, since German courts have reviewed it on multiple occasions and regulators have determined it fully complies with applicable European data protection law," the company said. "The use of authentic names on Facebook protects people’s privacy and safety by ensuring people know who they’re sharing and connecting with."