The 497 million euro (613 million dollar) fine and other requirements by the European Commission drew a sharp reaction on both sides of the debate on Microsoft in the United States.

Some lashed out at European intrusion into the US market, while Microsoft's technology rivals termed it a positive message for competition in the marketplace.

The US Department of Justice said Wednesday's EU antitrust ruling on Microsoft was "unfortunate" and could have unintended effects on the marketplace.

"Imposing antitrust liability on the basis of product enhancements and imposing 'code removal' remedies may produce unintended consequences," the department's antitrust chief R. Hewitt Pate said in a statement.

"Sound antitrust policy must avoid chilling innovation and competition even by 'dominant' companies. A contrary approach risks protecting competitors, not competition, in ways that may ultimately harm innovation and the consumers that benefit from it."

Pate said the US settlement of its long-running antitrust case "provides clear and effective protection for competition and consumers."

But Microsoft rivals called the ruling a vindication of their charges that the company used its dominance to crush competitors.

"This decision is fundamentally significant because the European Commission has formally declared that Microsoft's media player bundling strategy is illegal and has established the guideposts for future bundling cases," said Bob Kimball, vice president and general counsel at RealNetworks.

RealNetworks was a key firm in the EU case because it complained that Microsoft's "bundling" of its media software for audio and video within the Windows operating system was an abuse of the Microsoft monopoly position.

The EU ordered Microsoft to offer a European version of its dominant Windows operating system without the Media Player program within 90 days.

Microsoft also was ordered to disclose "complete and accurate" data to enable rival companies to offer low-end servers that can work with Windows within 120 days.

Server hardware and software maker Sun Microsystems also hailed the EU decision.

"This decision is important for consumers not only in Europe, but also for increased innovation and competition worldwide," said Lee Patch, Sun's vice president for legal affairs.

Ed Black of the Computer and Communications Industry Association, a trade group of Microsoft rivals, said the EU decision is a "confirmation of Microsoft's anti-competitive and illegal business tactics."

"The issues outlined today will prevent Microsoft from controlling the platform for the delivery and subsequent control over digital content," Black said.

"The decision prevents Microsoft from 'locking in' their media player and their proprietary format as the de facto standard, which would force developers and consumers alike to bow to whatever demands or taxes Microsoft wishes to place on digital content."

But US Senator Trent Lott lashed out at the ruling, calling it "an unprecedented intrusion into the US marketplace."

"It will force Microsoft to disclose to its competitors in Europe, and potentially to non-European companies as well, some of Microsoft's most valuable trade secrets and other intellectual property assets," Lott said.

The activist group Citizens Against Government Waste called the measure "draconian" and said it flew in the face of traditional acceptance of antitrust settlements in the US and Europe.

"The decision by the European Commission will have a global impact of negative consequence," CAGW president Tom Schatz said. "The EC should not be making decisions that are best left to the marketplace. Attempting to restrict the future design of software is unprecedented and has been rejected by the US courts."

Meanwhile Massachusetts Attorney General Tom Reilly, who represents the only US state rejecting the US settlement, said the EU "sent a very clear message" that Microsoft "is not above the law."

"The EU's ruling underscores what we've known all along, that the remedies Massachusetts is seeking in its case against Microsoft are both practical and possible," Reilly said.

"Without a court order that curbs Microsoft's illegal use of its monopoly power and holds it accountable for past, present and future actions, this company will continue to crush innovation, competition and consumer choice in the software industry here in the United States."

SPACE.WIRE