While high-tech industry vendors, including Apple Computer, Oracle, IBM and Compaq declined to comment on the ruling, lobbyist groups that represent Microsoft's opponents were quick to respond.
Ken Wasch, president of the Software & Information Industry Association (SIIA),which had lobbied against Microsoft throughout the antitrust trial, declared the appeals court ruling a victory for the anti-Microsoft forces.
"The Court of Appeals has now joined the US Justice Department, the District Court and most of the information technology industry in recognising that Microsoft's business practices are not just business as usual," Wasch said.
Microsoft's tactics have illegally cut off competitive technologies andeffectively deprived consumers of choice in the information technologyproducts they purchase, he said.
SIIA members include Deutsche Bank, Lucent Technologies, and Caldera.
Another group, ProComp, which is backed by Oracle, Sun Microsystems, Corel and other Microsoft rivals, said the ruling is good for consumers, good for competition and good for innovation in the industry.
ProComp spokesman and former White House prosecutor, Kenneth Starr, said: "Not only did the appellate court rule that Microsoft had violated antitrust laws, the decision to send the case back to the trial court to determine a remedy opens the door for hearings into the company's new initiatives, such as .Net and HailStorm."
Linux vendor Red Hat chief executive, Matthew Szulik, said: "I think we're dealing with the most vicious competitor of the last 30 years in technology, and they're only getting stronger."
The US Justice Department, which together with 19 states brought the case against Microsoft, issued a brief statement after the appeals court's decision became public."We are pleased that the Court of Appeals found that Microsoft had engaged in illegal conduct to maintain its operating system monopoly. We are reviewing the court's opinion and considering our options," the Justice Department statement said.
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