Microsoft's appeal essentially argues that a district court judge who held against it was incompetent as a gatekeeper and in striking the "delicate balance" needed in patent law disputes.
Microsoft's loss in a patent dispute with Toronto-based i4i LP means that it will have to stop selling Microsoft Word in U.S. markets. The issue concerns the use of "custom XML" in Word in the Microsoft Office 2003 and Microsoft Office 2007 productivity suites.