Tech editor Irene Tham answered.
It claimed this is to allow Facebook to suggest more phone contacts as friends and display more relevant ads. WhatsApp promised "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."
You can still opt out of such sharing within 30 days from Aug 25. Get moving if you object to the sharing.
Click on the "read more" option below the "agree" button on WhatsApp's new terms of service. Do not click on "agree" until you turn off the option that reads "Share my WhatsApp account information with Facebook to improve my Facebook ads and product experiences..."
If you have already accepted the new terms without first turning off the sharing option, you can still change the settings. Tap on the app's settings menu, select "account" and turn off the option that reads "Share my account info". This will stop WhatsApp from sharing your data with Facebook.
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