Terrific, predictable, horrifying reporting from Gizmodo:
Facebook is not content to use the contact information you willingly put into your Facebook profile for advertising. It is also using contact information you handed over for security purposes and contact information you didn't hand over at all, but that was collected from other people's contact books, a hidden layer of details Facebook has about you that I've come to call "shadow contact information." I managed to place an ad in front of Alan Mislove by targeting his shadow profile. This means that the junk email address that you hand over for discounts or for shady online shopping is likely associated with your account and being used to target you with ads.Facebook is not upfront about this practice. In fact, when I asked its PR team last year whether it was using shadow contact information for ads, they denied it. Luckily for those of us obsessed with the uncannily accurate nature of ads on Facebook platforms, a group of academic researchers decided to do a deep dive into how Facebook custom audiences work to find out how users' phone numbers and email addresses get sucked into the advertising ecosystem.
No one cared about security until Windows got hit by tons of viruses. The prevailing wisdom was that no one would care about privacy until Facebook wracked up similar abuses. The difference between then and now, though, couldn't be any more terrifying: Facebook is the virus.
