MasterCard maybe stepping into some hot antitrust trouble with the European Union amid reports of anti-competitive behavior between its swipe fees on credit and debit cards, said a Bloomberg Report.

According to the article, regulators may issue a “statement of objectives” as part of its antitrust probe to the credit card giant toward the end of July. For decades, EU regulators have monitored swipe fees on credit and debit cards and agreed that it reflects anti-competitive practices.

The most recent case, opened in 2013, points out the mounting regulatory concerns around excessive fees that tourists incur when shopping within the 28-nation bloc, as well as anti-competitive practices that limits banks from offering services to traders, the Bloomberg article said.

MasterCard’s “honor all cards” rule, which ensures that a merchant accepts all types of cards from the company is also subjected to some scrutiny from the EU antitrust regulator.

In light of a slew of regulatory changes, the European Union mandated a law that would cap interchange fees on card payments and slash the costs on transactions by 6 billion euros, annually. In effect, MasterCard was accused for launching a “mad campaign,” which illegally circumvented the caps on card payments.