Vertical Computer Systems is suing Microsoft for patent infringement related to Microsoft's .Net framework for building Windows-based software.
Vertical filed a lawsuit on 18 April in a US alleging that Microsoft has infringed on its Patent No. 6,826,744, for a "system and method for generating websites in an arbitrary object framework".
The patent is for Vertical's SiteFlash technology, which utilises Extensible Markup Language (XML) to create a component-based structure to build and efficiently operate websites.
The complaint says Microsoft is still wilfully infringing on the patent despite Vertical having put Microsoft on notice about it on 7 February. Vertical is asking for a jury trial.
Vertical describes itself as a global web services provider. It went public in 2000 but is not listed on a major stock exchange.
A Microsoft representative was not immediately available for comment.