The main complaint is Microsoft's bundling of its own markup language XAML with Vista.
According to ECIS, XAML has been positioned to compete with the universally used HTML (hypertext markup language), which is the code used to design web pages of sites in use today. ECIS contends that bundling XAML with Vista is an attempt to promote the creation of websites that work only with Vista.
Other complaints from ECIS focus on Microsoft's bundling of competing proprietary standards to Adobe's widely used PDF document creation product Acrobat and the ISO (international standards organization) approved open document format for document files ODF.
Microsoft has been criticised by parties among its competitors in both the commercial and open source software comunities for bundling a document creation application called XPS (XML paper specification) which competes with PDF. In addition, the software giant has been widely condemned for bundling and promoting its OOXML (open XML) document file format instead of ODF with Vista and its new office productivity suite Office 2007.
Rivals have long complained that the promotion of Microsoft proprietary standards such as XPS and OOXML are an attempt to cement the lock-in of users to Windows and Office. However, a platform independent Internet with Web 2.0 applications is widely seen as the biggest threat to Microsoft's desktop dominance. The bundling of XAML is being presented by ECIS as an attempt by Microsoft to threaten the platform independence of the Internet.
Microsoft has reportedly dismissed ECIS as a front for IBM and other competitors who want to avoid competition by using EU courts.