Deutsche Telekom’s T-Mobile Netherlands division has scored a win for zero rating after a court in Rotterdam ruled it can continue to offer its music streaming service to its customers.

The decision comes nearly four months after the Dutch Consumer and Market Authority (ACM) ordered T-Mobile Netherlands to end its zero-rated music streaming service. The ACM noted that while European telecom regulators do allow some services to be allowed for free or at “favorable rates” under strict conditions, the practice was forbidden under Netherlands law.

T-Mobile Netherlands was set to be fined 50,000 euros for each day it continued to offer the service, with a maximum penalty of 500,000 euros.

The court of Rotterdam acknowledged the Dutch prohibition, but ruled it didn’t apply because the Netherlands law was not authorized by the European Network Neutralization Regulation. Thus, the EU’s laws allowing zero rating supersede the Dutch regulations.

“Neither the net neutrality regulation nor the zero rating is prohibited,” the court wrote in its decision. “The manner in which T-Mobile offers the Computer-Free Music service is potentially contrary to the Network Neutralization Regulation, but ACM has deliberately not investigated, as it considered that zero rating was in any case prohibited. The court ruling means that T-Mobile can still continue with the Datavrije Music service.”

T-Mobile Netherlands CEO Soren Abildgaard called the ruling a “breakthrough in the Netherlands and in Europe.”

“Last October, we took a big and bold step to reach a new and very innovative service, against the prevailing belief in the established order, Datavrije Music. We firmly believed that this is in the interests of our customers. We can now continue innovating and break through boundaries to give our customers the full freedom of unlimited mobile internet,” he said.

The decision also comes two months after the FCC – under new Chairman Ajit Pai – closed its own investigation into the legality of zero-rated programs. Services under investigation included those from AT&T, Verizon, and T-Mobile US.