In this way, companies were not technically breaking their privacy policies—by purchasing Facebook app companies, the “third party” data brokers suddenly because the first-party owners of the data. For example, a data analytics company called RapLeaf was caught purchasing user information from various Facebook apps. Facebook eventually shut down RapLeaf, but the company simply sold itself to two data brokers, Acxiom and Tower Data. Today, Acxiom is a “Facebook Marketing Partner” which allows would-be advertisers to supplement that information they already have with the data that Acxiom has already gathered.
"People were writing apps manically—photo of the day, quizzes, any sort of garbage people would install so you would have a big user base to take the data. And there were absolutely cases where people developed Facebook apps for fun, got a huge user base, and then sold the apps for hundreds of thousands of dollars to a marketing company."
Data brokers create databases of information that’s pulled from Facebook and elsewhere. And once taken off the platform, data can be analyzed and re-imported later to be used to target people. Facebook allows advertisers to upload .CSV spreadsheets of information about people and use that information to specifically target people using its “Custom Audiences” product. That data can then be further used to target “Lookalike Audiences” on Facebook—people that data brokers might not know much about but who Facebook itself does know a lot about, according to Mislove.Facebook’s partnerships with data brokers like Acxiom and Experian allow advertisers to leverage what Facebook knows about you with what data brokers know about you to create a more complex profile of who you are.Together, Facebook and data brokers have made a list of things that it thinks I like, based on my likes, my apps, my web behavior, and, crutially, what data brokers already know about me. It also creates a rough profile of who I am:
"The incentive is to extract every iota of value out of users"