Elizabeth Denham, head of the ICO, sought the warrant after a whistleblower said Cambridge Analytica had gathered private information of 50 million Facebook users to support Donald Trump’s 2016 U.S. presidential campaign.

Britain is investigating whether Facebook, the world’s largest social media network, did enough to protect data.

…U.S. and European lawmakers have demanded an explanation of how the British consulting firm gained access to the data in 2014 and why Facebook failed to inform its users, raising broader industry questions about consumer privacy.

Investigators raid Cambridge Analytica’s London offices | VentureBeat

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