Wednesday, Spotify founder Daniel Ek announced that—following “careful consideration”—he and his team had decided to file a complaint against Apple with the European Commission (EC). The EC, of course, is responsible for ensuring “fair and nondiscriminatory” competition. Spotify has alleged that they previously tried to resolve their issues directly with the Apple Music team, though those efforts apparently didn’t go their way.

“To illustrate what I mean, let me share a few examples,” Ek said Wednesday. “Apple requires that Spotify and other digital services pay a 30% tax on purchases made through Apple’s payment system, including upgrading from our Free to our Premium service. If we pay this tax, it would force us to artificially inflate the price of our Premium membership well above the price of Apple Music. And to keep our price competitive for our customers, that isn’t something we can do.”

Furthermore, Ek added, not using the Apple payment system would saddle the service with “technical and experience-limiting restrictions” for users.