Federal Court of Appeal Clarifies the Test for Overbreadth and the Territorial Limits on Infringement

On March 20, 2026, the Federal Court of Appeal (per Locke J.A., Roussel J.A., and Heckman J.A.) (“FCA”) released an important decision in the patent dispute between ProSlide and WhiteWater, two competitors in the water slide industry. The ruling restores the validity of three of ProSlide’s patents relating to water slides but confirms that WhiteWater did not infringe any of them. The FCA’s decision provides helpful clarity on how Canadian courts treat patent scope, foreign manufacturing, and the level of disclosure required to show an invention works. It also provides further guidance on the correct approach for assessing allegations of invalidity for overbreadth.