In a reversal of previous pledges, WhatsApp is going to begin sharing data with Facebook in order to connect accounts, detect spam and improve ad targeting. This includes sharing your phone number and usage information for Facebook’s internal use, but not sharing any actual texts, since they are encrypted and neither Facebook or What’s has access to them.

WhatsApp is giving existing users 30 days to grandfather themselves into not sharing their data with Facebook. After that all users will be subject to their new Terms and Privacy Policy.

Here’s how WhatsApp describes the sharing of data with Facebook in the new Terms:

We joined the Facebook family of companies in 2014. As part of the Facebook family of companies, WhatsApp receives information from, and shares information with, this family of companies. We may use the information we receive from them, and they may use the information we share with them, to help operate, provide, improve, understand, customize, support, and market our Services and their offerings. This includes helping improve infrastructure and delivery systems, understanding how our Services or theirs are used, securing systems, and fighting spam, abuse, or infringement activities.

Facebook and the other companies in the Facebook family also may use information from us to improve your experiences within their services such as making product suggestions (for example, of friends or connections, or of interesting content) and showing relevant offers and ads. However, your WhatsApp messages will not be shared onto Facebook for others to see. In fact, Facebook will not use your WhatsApp messages for any purpose other than to assist us in operating and providing our Services.

WhatsApp is seeking new ways for its users, especially businesses, to utilize WhatsApp which will open up additional magnetization opportunities in the future. They are exploring the use of WhatsApp in business transactions with customers related to online orders and sales, appointments and reservations, delivery and shipping notifications, business updates to customers related to their products and services as well as integrating WhatsApp in company marketing.

“For example, you may receive flight status information for upcoming travel, a receipt for something you purchased, or a notification when a delivery will be made,” posted WhatsApp. “Messages you may receive containing marketing could include an offer for something that might interest you. We do not want you to have a spammy experience; as with all of your messages, you can manage these communications, and we will honor the choices you make.”

“But as we announced earlier this year, we want to explore ways for you to communicate with businesses that matter to you too, while still giving you an experience without third-party banner ads and spam,” added WhatsApp.”Whether it’s hearing from your bank about a potentially fraudulent transaction, or getting notified by an airline about a delayed flight, many of us get this information elsewhere, including in text messages and phone calls. We want to test these features in the next several months, but need to update our terms and privacy policy to do so.”

“We’re also updating these documents to make clear that we’ve rolled out end-to-end encryption,” they said. “When you and the people you message are using the latest version of WhatsApp, your messages are encrypted by default, which means you’re the only people who can read them. Even as we coordinate more with Facebook in the months ahead, your encrypted messages stay private and no one else can read them. Not WhatsApp, not Facebook, nor anyone else. We won’t post or share your WhatsApp number with others, including on Facebook, and we still won’t sell, share, or give your phone number to advertisers.”

“But by coordinating more with Facebook, we’ll be able to do things like track basic metrics about how often people use our services and better fight spam on WhatsApp,” the company stated. “And by connecting your phone number with Facebook’s systems, Facebook can offer better friend suggestions and show you more relevant ads if you have an account with them. For example, you might see an ad from a company you already work with, rather than one from someone you’ve never heard of.”