WhatsApp users have received a brief message stating that WhatsApp may share their data with Facebook if the need arises. It states that whenever users message businesses that use Facebook through the app, their data could be shared with Facebook.
The WhatsApp user data that may be shared with Facebook includes WhatsApp account registration, phone numbers, transaction data, service-related information, interaction information, mobile device information, IP addresses, and other information obtained or identified upon notice to the user based on his or her consent.
Facebook reveals that it will make use of the data to enable a better understanding of how their services work or how WhatsApp itself is used. They also see it as a means to improve their services and intend to make suggestions available for users. The platform also intends to personalize features and content, showing relevant offers and ads across the Facebook Company Products.
The new terms make sense only as a means of assisting WhatsApp integrating with Facebook more closely as they belong together.