Evo ga TL;DR:

In June 2014, a researcher named Aleksandr Kogan developed a personality-quiz app for Facebook […] about 270,000 people installed Kogan’s app […] but as with any Facebook developer at the time, Kogan could access data about those users or their friends. And when Kogan’s app asked for that data, it saved that information into a private database instead of immediately deleting it. Kogan provided that private database, containing information about 50 million Facebook users, to the voter-profiling company Cambridge Analytica […]

Cambridge Analytica has significant ties to some of President Trump’s most prominent supporters and advisers. […] Cambridge Analytica also used its “psychographic” tools to make targeted online ad buys for the Brexit “Leave” campaign, the 2016 presidential campaign of Ted Cruz, and the 2016 Trump campaign.

Navodno je zbog ovog skandala Zakerberg dampovao brdo FB akcija čime je spasio desetine miliona dolara svog bogatstva.