Some 2.7 million European Union citizens had their Facebook information leaked to data analytics firm Cambridge Analytica, the European Commission (EC) has revealed.
Facebook wrote to the EC to disclose the number of people who had their information “improperly shared”.
The EC said it is investigating the matter further the European Commissioner for Justice, Vera Jourova, will speak to Facebook’s co-founder and chief executive Mark Zuckerberg next week.
Jourova and Zuckerberg are expected to discuss what changes Facebook needs to make to protect users and how the US company must adapt to new EU data protection rules.
An EC spokesperson said:
Facebook confirmed to us that the data of overall up to 2.7 million Europeans or people in the EU to be more precise may have been improperly shared with Cambridge Analytica.
The letter also explains the steps Facebook has taken in response since.
The EU citizen data is part of the 87 million Facebook users who were revealed to have had their information mined by Cambridge Analytica.
Around 1.1 million of UK Facebook users had their data shared with Cambridge Analytica, according to a Facebook blog post, with most of users in the US.
Facebook shares have been spiralling since the UK’s Observer newspaper reported the social network’s close relationship with Cambridge Analytic last month.
Over $100 billion has now been wiped from Facebook’s market cap this year.
Zuckerberg admitted to making “a big mistake” on a press call on Wednesday but insisted he would not be stepping down as Facebook’s CEO.