(Bloomberg) -- Apple Inc. could be forced to scale back its App Store fees for developers after one of the European Union’s antitrust watchdogs said its commissions violate the bloc’s rules.

In the latest twist in a long-running clash between the Dutch Authority for Consumers & Markets and the US tech giant, officials ruled that Apple’s commission on certain app subscriptions are an abuse of the company’s market power.

In a confidential decision seen by Bloomberg, the Dutch regulator said Apple’s rules unfairly target companies that offer subscription services, such as Match Group Inc.’s dating app Tinder, which has to pay high commission rates on app sales, unlike ones that don’t have paid digital content.

Apple harms such companies “by charging them an additional and inexplicably higher fee,” according to the Dutch decision, which was sent in July.         

Apple had earlier offered to reduce app sale commission in the Netherlands from 30% to 27%, but the ACM’s confidential findings state this offer doesn’t go far enough. 

The decision could pave the wave for greater antitrust scrutiny across the 27-nation EU on the fairness of Apple’s fee structure for different apps. The European Commission in Brussels is already investigating how Apple restricts apps from informing users of cheaper subscriptions outside the app store.   

Apple didn’t respond to a request for comment. The company can oppose the ACM’s findings or attempt to remedy the concerns by restructuring its commissions. The ACM and the commission in Brussels declined to comment.

The Netherlands watchdog has been embroiled in a legal battle with Cupertino, California-based Apple since 2021, when it said Apple had breached Dutch competition rules in the dating app market following complaints sent to the regulator from a group of dating apps. 

Apple was fined a total of €50 million ($53.2 million) for failing to comply with an order to allow developers of dating apps to use third-party payments systems, before brokering a truce with the Dutch regulator by allowing dating-app providers to offer different payment methods. 

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