Back in 2012, Thomson Reuters tri struck a deal with the European Commission’s antitrust authorities over the short codes it uses to identify securities and their trading locations.

That deal has now been upheld by the EU’s highest court, marking a defeat for Thomson Reuters rival Morningstar morn , which had tried to have the settlement struck down.

The settlement was about Reuters Instruments Codes, or RICs. Following a three-year probe, the Commission found that Thomson Reuters—a company with a dominant position in the market for consolidated real-time data feeds—had been prohibiting its customers from using RICs to retrieve data from other providers’ feeds.

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Those other providers (such as Morningstar, an investment research firm based in Chicago) were also unable to use RICs in their mapping tables, which would have allowed interoperability with the systems of Thomson Reuters customers.

Thomson Reuters agreed to let its customers use RICs to retrieve data from its competitors’ feeds, and also to help them map between the RICs system and its rivals’ coding systems. Satisfied that this would make it easier to switch providers, the Commission ended its case.

Morningstar challenged that decision on the basis that the settlement didn’t let competitors such as itself use Thomson Reuters’ coding system.

However, on Thursday the Court of Justice of the European Union said the settlement gave customers the benefits they needed, and that there had been no need to include Thomson Reuters’ competitors in its license terms.

It pointed out that Thomson Reuters’ customers had everything they needed for them, as well as third-party software developers, to map RICs to the competing providers’ coding systems.

“Those commitments therefore represent a genuine improvement for Thomson Reuters’ customers since, in the absence of the need extensively to modify IT applications, they do not face prohibitive costs during a possible switch of providers,” the court said.