The European Union filed a complaint against Meta for a potential breach of antitrust policies.

Meta stock slumped 2.53% following the news on Monday. Shares shed 65.63% year-to-date as the social media giant faces continued hits over founder Mark Zuckerberg's $15 billion metaverse plans, along with harsh interest rate hikes beating down tech stocks across the board. 

"With its Facebook social network, Meta reaches globally billions of monthly users and millions active advertisers," EU Antitrust Commissioner Margrethe Vestager said in a statement. "Our preliminary concern is that Meta ties its dominant social network Facebook to its online classified ad services called Facebook Marketplace."

In a statement to Insider, Meta's head of competition for Europe, the Middle East, and Africa said, "The claims made by the European Commission are without foundation. We will continue to work with regulatory authorities to demonstrate that our product innovation is pro-consumer and pro-competitive." 

The tech giant could face a fine of up to 10% of its annual global revenue, the European Commission said. Based on its 2021 figures, that means the Facebook-parent company could pay up to $11.8 billion. 

The European Commission first launched a probe into Meta in June 2021 to investigate "possible anticompetitive conduct."

"This means Facebook users have no choice but to have access to Facebook Marketplace. Furthermore, we are concerned that Meta imposed unfair trading conditions, allowing it to use of data on competing online classified ad services," Vestager said. "If confirmed, Meta's practices would be illegal under our competition rules."