When Facebook bought the start-up WhatsApp in 2014, Jan Koum, one of WhatsApp’s founders, declared that the deal would not affect the digital privacy of his mobile messaging service’s millions of users.

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WhatsApp said on Thursday that it would start disclosing the phone numbers and analytics data of its users to Facebook. It will be the first time the messaging service has connected users’ accounts to the social network to share data, as Facebook tries to coordinate information across its collection of businesses.

WhatsApp is changing its policy as it begins building a moneymaking business after long placing little emphasis on revenue. The company plans to allow businesses to contact customers directly through its platform. A similar strategy is already being tested on Facebook Messenger, a separate messaging service Facebook owns.

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Among the changes, Facebook will be able to use a person’s phone number to improve other Facebook-operated services, such as making new Facebook friend suggestions, or better-tailored advertising, WhatsApp added. It said the data-sharing would also be used to fight spam text messages across it