A US court has upheld a $290m (£182m) verdict against Microsoft in a patent dispute with Canadian company i4i.
The federal appeals court also upheld an injunction banning the company from selling Word software that includes the patented technology in the US.
The injunction is set to go into effect on 11 January.
Microsoft said the ban would prohibit the sale of all available versions of Microsoft Word and Microsoft Office software.
Microsoft was accused by i4i of infringing on a 1998 XML patent in its Word 2003 and Word 2007 programs.
Word uses XML, or Extensible Markup Language, to open .XML, .DOCX, and .DOCM files.
Microsoft said it might file further appeals, but that it was “moving quickly” to comply with the injunction.
