More revelations of data firms harvesting social profiles are emergeing.
The Cambridge Analytica whistleblower claims a second analytics company has also been exploiting internet users' profiles.
Christopher Wylie has told the British MPs that Canadian firm Aggregate IQ worked on software to identify Republican voters in the last U.S. Presidential election.
He's also claimed it was part of a plan to ensure that Britain voted in favour of Brexit.
The boss of Facebook has refused a request to appear before MPs, despite admitting that 50 million users had their personal details exploited.