But how would Clearbit know the Facebook profile linked to that email address? The only way is: 1) Scraping Facebook by automating the process of searching fo

But how would Clearbit know the Facebook profile linked to that email address? The only way is: 1) Scraping Facebook by automating the process of searching for FB profiles based by email (most likely) 2) Having access to the same API Cambridge had years ago, where it's possible they downloaded the data from someone that had me in their friend's list (unlikely, this profile has ZERO friends :) Of course if you ask Clearbit this, they'll hide behind the guise that they just look at publicly available data, or they bought it from a "trusted 3rd party". Where does the rabbit hole lead?