Alexander Nix, CEO of Cambridge Analytica arrives at the offices of Cambridge Analytica in central London, Britain, March 20, 2018.

A man films Christopher Wylie, a whistleblower who formerly worked with Cambridge Analytica, the consulting firm that is said to have harvested private information from more than 50 million Facebook users, for a Facebook live cast as he speaks at the Frontline Club in London, Britain, March 20, 2018.

The nameplate of political consultancy, Cambridge Analytica, is seen in central London, Britain March 21, 2018.

The building housing the offices of Cambridge Analytica is seen in central London, Britain, March 20, 2018. REUTERS/Henry Nicholls

Christopher Wylie, a whistleblower who formerly worked with Cambridge Analytica, the consulting firm that is said to have harvested private information from more than 50 million Facebook users, arrives at the Frontline Club in London, Britain, March 20, 2018.

The offices of political consultancy, Cambridge Analytica, are seen in central London, Britain March 21, 2018.

Labels indicate the location of the offices of Cambridge Analytica in central London, Britain, March 20, 2018.

A photographer takes a photograph of the nameplate of political consultancy, Cambridge Analytica, in central London, Britain March 21, 2018.

Christopher Wylie, a whistleblower who formerly worked with Cambridge Analytica, the consulting firm that is said to have harvested private information from more than 50 million Facebook users, speaks at the Frontline Club in London, Britain, March 20, 2018. REUTERS/Henry Nicholls TPX IMAGES OF THE DAY - RC1BB51A8A90

People walk past the building housing the offices of Cambridge Analytica in central London, Britain, March 20, 2018.

A man delivers storage crates to the building that houses the offices of Cambridge Analytica in central London, Britain, March 20, 2018.

Men deliver storage crates to the building that houses the offices of Cambridge Analytica in central London, Britain, March 20, 2018.

A man films Christopher Wylie, a whistleblower who formerly worked with Cambridge Analytica, the consulting firm that is said to have harvested private information from more than 50 million Facebook users, for a Facebook live cast as he speaks at the Frontline Club in London, Britain, March 20, 2018.

The window of political consultancy, Cambridge Analytica, is seen at their office in central London, Britain March 21, 2018.

Mark Turnbull, Managing Director of SCL Elections/Cambridge Analytica arrives at the offices of Cambridge Analytica in central London, Britain, March 20, 2018.