New antitrust charges against Microsoft 

The industry group, labelled the 'European Committee for Interoperable Systems', had already joined the Commission's ongoing antitrust case against Microsoft in May 2005. They have now taken the legal battle with Microsoft a step further by filing a complaint of their own. The new complaint replicates the tenor of the Commission's March 2004 antitrust ruling against Microsoft and applies it to features of Microsoft's upcoming Window's Vista operating system, which the rivals say may lock competitors out of developing and modifying software of their own. 

In addition, Microsoft's competitors repeat accusations brought forward earlier on alleged Microsoft business practices such as using its dominance in the operating systems market to promote other products by bundling software up, withholding interface information that competitors need to develop their own applications, using digital rights management (DRM) technology to lock rivals' software out from Windows computers and withholding file format information. In addition, the rival companies say, Microsoft is trying to "proprietise the internet" with the introduction of its new XAML mark-up language for web applications, which they say will work only with the Windows operating system. 

Microsoft described ECRI as "a front for IBM", and says that the rival company's complaint came as no surprise: "When faced with innovation, they choose litigation."