"The European Commission has opened a formal antitrust investigation to assess whether Facebook violated EU competition rules by using advertising data gathered in particular from advertisers in order to compete with them in markets where Facebook is active such as classified ads. The formal investigation will also assess whether Facebook ties its online classified ads service 'Facebook Marketplace' to its social network, in breach of EU competition rules", the commission said in a press release.
According to the press release, the European Commission will cooperate closely with the UK Competition and Markets Authority, which has launched its own independent investigation into Facebook's use of data.
Introduced in 2016, Facebook Marketplace is estimated to be used by almost a billion users in 70 countries. However, the social media giant has been accused of using the data it collects from users to undermine its rivals in online advertising.