Facebook “shadow profile” is an industry term for personal data amassed by Facebook from multiple sources: info you provide, plus information shared by your friends (via the sharing of their contact lists, for example), and online tracking pixels. Because the data in the profile is not just provided by the individual in question, it is not limited to Facebook users, nor is it controlled by the target individual.What is a #Facebook shadow profile? It is personal data amassed from multiple sources. #privacyClick To Tweet
The first use of the term was in 2013*, when a bug in Facebook revealed that phone data was collected not just from the user, but also from the phonebooks of friends. The phrase returned to the headlines in April, 2018, when the US congress House Energy and Commerce Committee questioned Mark Zuckerberg, Facebook founder and CEO, about Facebook shadow profiles. Zuckerberg denied that such profiles existed, and insisted that Facebook users control their own data.
So, are Facebook shadow profiles real? Evidence exists, via security breaches and experimentation, that Facebook (and other powerhouse data aggregators) do collect and combine data from multiple sources. For example, even if you have never provided Facebook with your phone number, it is possible that they already know it.
Which leads to an important question: how do users control data that we don’t even know is out there? The long road to controlling the data monster has just begun.
Science Advances, Leaking privacy and shadow profiles in online social networks. Aug 4, 2017.
TechCrunch, Zuckerberg denies knowledge of Facebook shadow profiles, Apr 11, 2018.