LONDON (AP) — European Union regulators filed antitrust charges Tuesday against Amazon, accusing the e-commerce giant of using its access to data to gain an unfair advantage over merchants using its platform.

The EU’s executive Commission, the bloc’s top antitrust enforcer, issued the charges after it started looking into the company two years ago. Adding to Amazon’s regulatory headaches, the EU also opened a second investigation into whether the company favors product offers and merchants that use its own logistics and delivery system.

It’s the latest effort by Executive Vice President Margrethe Vestager, the EU commissioner in charge of competition issues, to curb the power of big technology companies. She has slapped Google with antitrust fines totaling nearly $10 billion and opened twin antitrust investigations this summer into Apple. The U.S. has started taking a tougher line as well, suing Google this year for abusing its dominance in online search and advertising.

It’s not a problem that Amazon is big and successful but “our concern is very specific business conduct which appears to distort genuine competition,” Vestager said.

EU officials focused on the company’s dual role as a marketplace and retailer. In addition to selling its own products, the U.S. company allows third-party retailers to sell their own goods through its site.