Michel Vulpe and i4i Inc., the tiny Toronto technology firm he founded, won a key ruling this week in a patent infringement case that could force Microsoft Corp. to stop selling current versions of its popular Word software in the United States.

A Texas judge found Microsoft “wilfully” infringed on i4i’s patent by including certain features in the 2003 and 2007 versions of its popular word processing software.

The ruling upheld an earlier decision against Microsoft that was issued in May and added another $90 million US in damages to the court’s initial award of $200 million.