You might remember that a small and relatively unknown company called i4i was successful in suing software giant Microsoft in the US District Court for the Eastern District of Texas, Tyler division back in the summer of 2009. The suit centered on i4i's allegation that Microsoft had willingly infringed on i4i patents that cover Extensible Markup Language or XML as covered by patent 5,787,449.
i4i was seeking an injunction against Microsoft and damages from Microsoft for use of the tech covered by the patent that was used in Microsoft Word's XML editing capability. Microsoft naturally appealed the decision since Word and the Office suite are the bread and butter of the software giant along with the Windows operating system.
I4i has announced that Microsoft has taken the case all the way to the Supreme court and this is the last chance that Microsoft has to get the decision overturned. Whether or not Microsoft can win here when it has lost on all other appeals is questionable at best. i4i also notes that the USPTO has denied Microsoft's second request for a re-examination of the patent owned by i4i at the heart of the case. The originally damages awarded to i4i totaled $290 million along with a permanent injunction that started in January 2010.