The data firm credited with helping Donald Trump win the 2016 US election has been suspended from Facebook.
At the centre of the row is University of Cambridge professor Aleksandr Kogan who, according to Facebook, made a “personality app” that in fact gathered data he then sold to third parties.
Facebook said it had now received reports that Cambridge Analytica and others had not destroyed all the data that was obtained in breach of Facebook’s policies.
Cambridge Analytica has yet to comment on the decision.
Facebook announced the move during the early hours of Saturday morning in the UK – the BBC has not yet been able to reach Prof Kogan. The University of Cambridge has yet to comment.
Cambridge Analytica recently rose to prominence for its significant role in President Trump’s election campaign, where it provided intricate data on the thoughts of American voters. Former presidential advisor Steve Bannon was on its board of directors.
The company also played a role in the Brexit referendum campaign.
Facebook said the suspension would remain in place “pending further information”.
Facebook’s deputy legal counsel Paul Grewal wrote at length about the decision in a blog post.
“In 2015, we learned that a psychology professor at the University of Cambridge named Dr. Aleksandr Kogan violated our platform policies,” Mr Grewal wrote.
Prof Kogan is said to have created an app called “thisisyourdigitallife”. It was accessed by approximately 270,000 people, Facebook said.
“In so doing, they gave their consent for Kogan to access information such as the city they set on their profile, or content they had liked, as well as more limited information about friends who had their privacy settings set to allow it.”
Users who downloaded it were told they were taking a personality prediction test that was part of a “research app used by psychologists”.
While that was initially true – Prof Kogan is a psychologist – Facebook said the data was then kept and sold on to third-parties including Cambridge Analytica and its parent company Strategic Communications Laboratories. Another recipient was said to be an employee at Eunoia Technologies.
Mr Grewal claimed: “Although Kogan gained access to this information in a legitimate way and through the proper channels that governed all developers on Facebook at that time, he did not subsequently abide by our rules.”
Facebook says that, if notified, the companies who bought the data that it must be deleted immediately. At the time Facebook said it was given assurances the information would be destroyed.
“Several days ago, we received reports that, contrary to the certifications we were given, not all data was deleted,” Mr Grewal said.
“We are moving aggressively to determine the accuracy of these claims. If true, this is another unacceptable violation of trust and the commitments they made.”
The firm said it would not rule out legal action over the incidents.
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