Microsoft, the world’s largest software maker, faces two new antitrust cases. This time it is the European Commission that opened the most recent antitrust investigations regarding Microsoft’s activities. The European Commission represents the European Union’s antitrust watchdog and it has powers to fine companies up to 10 percent of their global annual revenues for their competition abuses. The institution’s most recent investigation of Microsoft’s business practices was prompted by the popular software maker’s rivals’ complaints in the European Committee for Interoperable Systems. The ECIS includes companies such as Sun Microsystems, Red hat, IBM, Adobe, Oracle and several others.

The European Commission said on Monday that it was trying to discover whether Microsoft was violating monopoly laws by failing to make its products interoperable with rivals’ offerings and by illegally bundling its popular Internet Web browser (Internet Explorer) with Windows operating system. “The initiation of proceedings does not imply that the Commission has proof of an infringement. It only signifies that the Commission will further investigate the case as a matter of priority,” the European Commission said in a statement.

On the other hand, ECIS officially claimed that “Microsoft continues to use its desktop monopolies to restrict competition.” ECIS also accused Microsoft of having refused to release the documentation the groups’ members need for making their own products work with Microsoft Office and the .NET Framework programming environment.

Microsoft replied these accusations by saying that it will fully cooperate with the European Union’s institution. "We are committed to ensuring that Microsoft is in full compliance with European law and court obligations," Microsoft said in statement.