What I call the “Facebook phone number ad thing” has been in the news a lot. Facebook confirmed it uses your two-factor authentication phone number for advertising purposes. But let’s cut through the clickbait headlines.
One of the many ways that ads get in front of your eyeballs on Facebook and Instagram is that the social networking giant lets an advertiser upload a list of phone numbers or email addresses it has on file; it will then put an ad in front of accounts associated with that contact information.
Facebook is not handing out your phone number to advertisers. What is happening is if an advertiser already has a phone number, they can go to Facebook and say: “Please show an ad to the profile with this phone number.” The only difference now is that Facebook uses your two-factor authentication number for this, even if you haven’t put your phone number in your profile elsewhere. Still sh*tty though.