German antitrust authorities restricted Facebook's ability to assign data from third-party apps to users' profiles Thursday, a move the company disagreed with and said it intends to appeal.

Germany's Federal Cartel Office, the Bundeskartellamt, said Facebook can continue to collect data from apps it owns, including WhatsApp and Instagram, but can't assign data from the apps to users' Facebook profiles without voluntary consent. Facebook will no longer be able to collect German users' data from third-party websites without voluntary consent.

“Voluntary consent means that the use of Facebook's services must not be subject to the users' consent to their data being collected and combined in this way,” Bundeskartellamt president Andreas Mundt said in a press release. “If users do not consent, Facebook may not exclude them from its services and must refrain from collecting and merging data from different sources.”

He said Facebook used its market power to force users into allowing “practically unrestricted collection” of their data from non-Facebook sources.

In a blog post published shortly after the decision, Facebook Ireland's head of data protection Yvonne Cunnane and director and associate general counsel Nikhil Shanbhag said the “decision misapplies German competition law to set different rules that apply to only one company.”

“Every day, people interact with companies that connect and use data in similar ways. And all of this should be—and is—a legitimate area of focus for regulators and policymakers around the world. Yet the Bundeskartellamt is trying to implement an unconventional standard for a single company,” Cunnane and Shanbhag said in the post.

The two outlined Facebook's argument against Germany's restrictions: that popularity in a market is not necessarily dominance, with 40 percent of Germans not using Facebook, that sharing data across apps and websites can improve services and safety and that the company complies with the European Union's General Data Protection Regulations.

Facebook's data processing should be regulated by data authorities rather than anti-competition authorities, Cunnane and Shanbhag said, adding Germany's order “threatens to undermine this.” The Mountain View, California-based company has its European headquarters in Dublin, falling under the Irish Data Protection Commission's jurisdiction.

“This is the point we'll continue to make to the Bundeskartellamt and defend these important arguments in court, so that people and businesses in Germany can continue to benefit from all of our services,” Cunnane and Shanbhag said.

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