Matthew Szulik, chairman and chief executive officer of Red Hat, hailed a European Union court ruling Monday against Microsoft as “great news for innovation and consumer choice.”

The court dismissed Microsoft’s appeal of an EU antitrust order. The order requires Microsoft to share communications code with rivals and to sell a version of Windows without a Media Player.

The court also upheld a $613 million anti-trust fine against Microsoft.

Red Hat, a developer of open source Linux software solutions, has battled with Microsoft for years.

“Today’s decision by the Court of First Instance in Luxembourg in the Microsoft matter is great news for innovation and consumer choice, both in Europe and around the world,” Szulik said in a statement issued by Red Hat shortly after the court decision was announced. “The Court has confirmed that competition law prevents a monopolist from simply using its control of the market to lock in customers and stifle new competitors.

“In our business, interoperability information is critically important and cannot simply be withheld to exclude all competition. Given Red Hat’s firm belief that competition, not questionable patent and trade secret claims, drives innovation and creates greater consumer value, we were pleased with the overall decision and look forward to examining the decision in greater detail,” Szulik added.

The rivalry between Red Hat and Microsoft has heated up in recent months following a deal struck between Microsoft and Novell, another open source developer, about intellectual property and indemnification. Microsoft has often said Linux infringes on Microsoft code. Red Hat and others have denied that claim.

Red Hat has also rebuffed Microsoft when it sought a Novell-like deal with the Raleigh-based company

In the EU-Microsoft case, the EU Court of First Instance ruled against Microsoft on both parts of the case, saying the European Commission was correct in concluding that Microsoft was guilty of monopoly abuse in trying to use its power over desktop computers to muscle into server software.

It also said regulators had clearly demonstrated that selling media software with Windows had damaged rivals.

"The court observes that it is beyond dispute that in consequence of the tying, consumers are unable to acquire the Windows operating system without simultaneously acquiring Windows Media Player," it said. "In that regard, the court considers that neither the fact that Microsoft does not charge a separate price for Windows Media Player nor the fact that consumers are not obliged to use that Media Player is irrelevant."

But it did overturn regulators’ decision to appoint a monitoring trustee to watch how Microsoft had complied with the ruling, saying the Commission had exceeded its powers by ordering Microsoft to pay for all the costs of the trustee.

Microsoft can appeal the decision to the EU’s highest court, the European Court of Justice, within two months.

"I don’t want to talk about what will come next," said Microsoft lawyer Brad Smith in answer to questions about the possibility of an appeal. "We need to read the ruling before we make any decision."

European Union Competition Commissioner Neelie Kroes urged Microsoft to move now to "comply fully" with the 2004 antitrust ruling.

"The court has upheld a landmark Commission decision to give consumers more choice in software markets," Kroes said in a statement. "Microsoft must now comply fully with its legal obligations to desist from engaging in anticompetitive conduct. The Commission will do its utmost to ensure that Microsoft complies swiftly."

The European Committee for Interoperable Systems called the ruling a good result.

"It’s a very good day, for it signals that there will be fair competition for the sector," said Maurits Dolmans, a lawyer for the group.

In its 248-page ruling, the court upheld both the Commission’s argument and its order for Microsoft to hand over information on server protocols to rivals. Microsoft had claimed these were protected by patents and the Commission was forcing it to give away valuable intellectual property at little or no cost.

The court confirmed "that the necessary degree of interoperability required by the Commission is well founded and that there is no inconsistency between that degree of interoperability and the remedy imposed by the Commission.