The European Commission is investigating allegations that Microsoft is violating anti-trust rules in the European Union, a Commission official who asked not to be identified said.

"We have two complaints that are currently being investigated, one filed by a rival software maker and another by a personal computer manufacturer," the official said in response to questions about the Commission's reaction to Friday's ruling, by a US District Court, that found that Microsoft is a monopoly.

"Those facts are not correct," John Frank, director of law and corporate affairs, Microsoft Europe, said to IDG: "In the normal course of business there are certain open matters," he said. "It would be inappropriate for either the Commission, or Microsoft to make further comments."

According to the Commission, however, the investigations concern allegations that the company is abusing its dominant position in the European market for operating systems running on PCs and servers.

At least one of the investigations has been underway since last December, but there is no time limit for a Commission ruling, the Commission official said.

The European Commission declined to comment officially on the US court ruling, explaining that the institution never comments on rulings by foreign courts, Jonathan Faull, deputy spokesman for the Commission said Monday in response to questions.

The US and the EU cooperate successfully in the anti-trust field, and the Microsoft case has been the subject of regular discussions at various levels of government, Faull stressed. The Transatlantic Competition Agreement promotes cooperation between the US and EU anti-trust authorities through exchange of information.

Despite concerns of its own, the Commission has taken a backseat to the US in the Microsoft investigations, because the US government has a greater ability to act, former Commission spokesman Stefan Rating told journalists last year. At that time, the Commission also expressed confidence in Microsoft to apply any agreements accepted in the US to the European market.

Although Microsoft is expected to appeal the ruling, Frank confirmed: "publicly and privately, we have told the Commission that any remedy that comes from the Department of Justice case, will be applied on a global basis".