META Meta Platforms Inc

By Friedrich Geiger 

BERLIN--A German privacy watchdog has ordered Facebook Inc. to stop collecting user data from its messenger subsidiary WhatsApp, the latest clash between European privacy authorities and the social-network company.

Hamburg's commissioner for data protection, Johannes Caspar, said user-data exchange between the two services infringed German data-protection law after WhatsApp changed its data-sharing terms last month. The Federation of German Consumer Organizations sent WhatsApp a similar warning earlier this month.

A Facebook spokeswoman said, "We will appeal this order and we will work with the Hamburg [authority] in an effort to address their questions and resolve any concerns."

Facebook complied with EU data-protection law, she said.

Mr. Caspar said Facebook reneged on a pledge it made on acquiring WhatsApp in 2014, when it said the services would keep user data separate. His office's order, Mr. Caspar said, protected the data of roughly 35 million WhatsApp users in Germany.

WhatsApp has notified existing users of the change and given them the opportunity to opt out. In Mr. Caspar's view, however, Facebook is an independent entity that also has to ask the permission of WhatsApp users.

"It has to be their decision whether they want to connect their accounts with Facebook," he said. "Facebook must ask their permission in advance (but) this did not happen."

In Germany, Mr. Caspar's office oversees Facebook's privacy practices because the company has its national office in Hamburg. His order forbids Facebook from collecting and storing data of German WhatsApp users and requires the company to delete data it has already received.

WhatsApp's plan to share user information with Facebook immediately raised concerns among privacy regulators in Europe when it was announced last month. The Article 29 Working Party, a body representing the European Union's 28 national data-protection authorities, at the time said its members were scrutinizing the WhatsApp change of terms "with great vigilance."

The change of terms is just one in a series of concerns about Facebook's data policies. France threatened the company with fines if it didn't change how it handled data, and Germany's Federal Cartel Office earlier this year began an investigation into whether Facebook abused its dominance as a social network to harvest personal information.

According to Mr. Caspar, people who don't use WhatsApp or Facebook were also at risk of having their details collected should WhatsApp forward data that it collected from users' address books of external contacts.

"Facebook's answer that it hasn't done this yet nevertheless is a reason to worry that the magnitude of the data-protection breach will have a much more severe impact."

As part of its warning earlier this month, the Federation of German Consumer Organizations said it had given WhatsApp until Sept. 21 to agree to a cease-and-desist order regarding data transfer to Facebook. The federation's spokesman Timo Beyer said WhatsApp asked for a postponement of the deadline until Oct. 14, which was granted.

Write to Friedrich Geiger at friedrich.geiger@wsj.com

(END) Dow Jones Newswires

September 27, 2016 11:23 ET (15:23 GMT)

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