The appellants appealed a finding that they infringed the respondents' patent for a dual action washing machine agitator with flexible vanes.
The appellants argued the patent was invalid due to double patenting, asserting that an earlier patent already covered the invention or rendered it obvious.
The Supreme Court of Canada dismissed the appeal, affirming the validity of the patent and the finding of infringement.
In doing so, the Court established that 'purposive construction' is the proper approach to patent claims construction for both validity and infringement analyses.
