WhatsApp just announced it will start sharing users’ phone numbers and other info with Facebook. The messaging app is known for its strong privacy policies, but after being acquired by Facebook two years ago, that’s changing.

Facebook shouldn’t be mining data from 1 billion WhatsApp users around the world. But that’s just what it plans to do by using WhatsApp user phone numbers and smartphone information to provide targeting ads on Facebook.  

Countless users come to WhatsApp because of its iron-clad encryption and ad-free interface. But with its recently announced privacy policy, Facebook is turning the tables by using WhatsApp as a gold mine for sensitive user information. We need to stop this shift before it gets even worse.

Tell Facebook not to compromise WhatsApp’s privacy policies by mining user data for ads.

Since Facebook bought WhatsApp in a $21.8 billion deal, it’s been looking for ways to get its money’s worth. Apparently Facebook executives have decided to cash in on the lucrative data that WhatsApp has long kept private.

During the acquisition, both companies pledged WhatsApp would operate separately from its parent, and the U.S. Federal Trade Commission even warned them against changing WhatsApp privacy settings without users’ consent. But now, WhatsApp is giving users’ just 30 days to opt out of sharing sensitive information with Facebook.

We’ve taken Facebook to task for violating user privacy in the past, like when a half million of us came together to oppose an ultimately abandoned Facebook app feature that would listen in to user’ conversations. Now, we need to raise our voices and preserve the privacy policies that make WhatsApp what it is.