In March 2004 the Commission found Microsoft guilty of breaking competition law by leveraging its near monopoly in the market for PC operating systems onto the markets for work group server operating systems and for media players.
It imposed a fine, ordered Microsoft to offer an alternative stripped-down version of Windows, and ordered the firm to publish some of its interfaces, so that competitors could make their products interoperable with Windows.
Speaking to the New York Times, Competition Commissioner Neelie Kroes, explained, "We have had informal complaints, and we are using our time now to look at them”.
"We're not going to wait and do nothing,” she added, but refused to give any further details.
Commission spokesman Jonathon Todd later stressed that the regulator was not planning to take formal action at present.
“The European Commission is not intending at the moment to open a new case against Microsoft. The Commission is, however, determined to ensure the proper application of the March 2004 decision and in particular the remedies imposed by that decision," he told Reuters.
European anti-software patent campaigner Florian Mueller believes that the EU Commission "favours bureaucracy over a free market and lacks a truly convincing strategy for the European software market".
The Commission’s actions were about 15 years too late, according to Mueller. In his view, “If they want to provide for a more competitive software market, they should establish a superior [intellectual property rights] system in Europe and leverage open-source software as an opportunity for economic growth and cost savings."