The spat between Spotify and Apple is going to be the focus on a new investigation from the EU, according to a report from the FT.

The paper reported today that the European Commission (EC), the EU’s regulatory body, plans to launch a competition inquiry around Spotify’s claim that the iPhone-maker uses its position as the gatekeeper of the App Store to “deliberately disadvantage other app developers.”

In a complaint filed to the EC in March, Spotify said Apple has “tilted the playing field” by operating iOS, the platform, and the App Store for distribution, as well as its own Spotify rival, Apple Music.

In particular, Spotify CEO Daniel Ek has said that Apple “locks” developers and their platform, which includes a 30 percent cut of in-app spending. Ek also claimed Apple Music has unfair advantages over rivals like Spotify, while he expressed concern that Apple controls communication between users and app publishers, “including placing unfair restrictions on marketing and promotions that benefit consumers.”

Spotify’s announcement was unprecedented — Ek claimed many other developers feel the same way, but do not want to upset Apple by speaking up. The EU is sure to tap into that silent base if the investigation does indeed go ahead as the FT claims.

Apple bit back at Spotify’s claims, but its response was more a rebuttal — or alternative angle — on those complaints. Apple did not directly address any of the demands that Spotify put forward, and those include alternative payment options (as offered in the Google Play store) and equal treatment for Apple apps and those from third-parties like Spotify.

The EU is gaining a reputation as a tough opponent that’s reining in U.S. tech giants.

Aside from its GDPR initiative, it has a history of taking action on apparent monopolies in tech.

Google fined €1.49 billion ($1.67 billion) in March of this year over antitrust violations in search ad brokering, for example. Google was fined a record $5 billion last year over Android abuses and there have been calls to look into breaking the search company up. Inevitably, Facebook has come under the spotlight for a series of privacy concerns, particularly around elections.

Pressure from the EU has already led to the social network introduce clear terms and conditions around its use of data for advertising, while it may also change its rules limiting overseas ad spending around EU elections following concern from Brussels.

Despite what some in the U.S. may think, the EU’s competition commissioner, Margrethe Vestager, has said publicly that she is against breaking companies up. Instead, Vestager has pledged to regulate data access.

“To break up a company, to break up private property would be very far-reaching and you would need to have a very strong case that it would produce better results for consumers in the marketplace than what you could do with more mainstream tools. We’re dealing with private property. Businesses that are built and invested in and become successful because of their innovation,” she said in an interview at SXSW earlier this year.