Cambridge Analytica: What is the company now embroiled in Facebook data controversy?

British data analytics firm Cambridge Analytica is at the centre of controversy in the US and UK after two newspapers reported the company harvested personal data about Facebook users beginning in 2014. Best known for assisting the 2016 presidential campaign of US President Donald Trump, Cambridge Analytica is now facing a government search of its London office, questions from US state authorities, and a demand by Facebook that it submit to a forensic audit. The UK's Information Commissioner has announced she is seeking a warrant to probe the company's servers – and also that she was forced to tell Facebook to "stand down" its own enquiries after its auditors and lawyers visited Cambridge Analytica's offices. "Such a search would potentially compromise a regulatory investigation," Elizabeth Denham said. Here is some of what is known about Cambridge Analytica.