The US Supreme Court on Thursday upheld a lower court ruling ordering software giant Microsoft to pay $290 million to a Canadian company in a patent infringement case. Toronto-based i4i Inc. sued the Redmond, Washington-based Microsoft in 2007 claiming that some versions of popular Word software violated patent rights it held to XML technology. In December 2009, a US Court of Appeals upheld a jury verdict and lower court ruling in the case ordering Microsoft to pay $290 million to i4i. The Supreme Court unanimously upheld the appeals court ruling on Thursday. 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.