It’s been less than a week since WhatsApp announced it would start sharing some user data with parent company Facebook, but in that short time, app users and privacy advocates alike have raised a ruckus over what they see as a broken promise. Now, some consumer privacy watchdog groups have filed a formal complaint with the FTC, asking them to look into it.

The complaint (PDF) comes from the Electronic Privacy Information Center (EPIC) and the Center for Digital Democracy (CDD). The groups ask the FTC to investigate the new terms that Facebook and WhatsApp have set, saying it constitutes “an unfair and deceptive trade practice,” which is the legal term for all those misleading things the FTC’s responsible for quashing.

The change, EPIC and CDD claim, is widely viewed as a reduction of users’ privacy. They cite several tech journalists, international regulators, and experts who all shared negative views of the news when it broke. They also cite the FTC’s own previous communications to Facebook and WhatsApp about, well, exactly this.

Back when Facebook first announced its plans to buy WhatsApp back in 2014, the FTC warned the two to play nice when it came to users’ privacy. Facebook has been subject to strict privacy rules since a 2011 settlement with the FTC, and the feds warned the social network that it has to uphold its end of the bargain.

At the time, in 2014, the FTC advised, “WhatsApp must continue to honor these [existing] promises to consumers.”

And also at the time, both companies’ executives promised to do just that. In 2014, Mark Zuckerberg said that Facebook was “absolutely not going to change plans around WhatsApp and the way it uses user data.” The CEO of WhatsApp echoed the sentiment, saying flatly, “We will never change our privacy policy.”

Given that the existing promise has now changed, as has the privacy policy, EPIC contends, Facebook and WhatsApp are now violating a promise to their billions of users, and are violating Section 5 of the FTC Act.

“When Facebook acquired WhatsApp, WhatsApp made a commitment to its users, to the Federal Trade Commission, and to privacy authorities around the world not to disclose user data to Facebook,” EPIC president Marc Rotenberg said in a statement. “Now they have broken that commitment.”

For what it’s worth, WhatsApp users have 30 days to opt out of having their data shared with Facebook. Clock’s a-ticking!

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