Facebook allows targeting by numbers

Journalist Kashmir Hill experimented with Facebook, launching an ad targeted at the familiar Alan Mislov. The advertisement was aimed at a number that he never indicated on the social network. It is also noted that Facebook allows targeting by numbers that were used for two-factor authentication, and numbers from contacts of other users. That is, to get your number, the advertiser needs a pair of your friends.
Representatives of the company confirmed this information and noted that the social network uses contacts for more accurate targeting.

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