Corlac Inc. et al. v. Weatherford Canada Ltd. et al.

The Appellants appealed the findings of the Judge that the patent was valid and infringed. Seven issues were raised on appeal: the Court of Appeal returned the issue of infringement of one claim to the Judge for redetermination and dismissed the remaining issues.

The Court of Appeal refused to interfere with the Judge’s finding with respect to the issue of co-inventorship pursuant to section 53(1) of the Patent Act. In particular, the Court of Appeal agreed with the Judge that materiality is fact-specific, and the misstatement in this case was immaterial. The Court of Appeal agreed with the Judge that section 73(1)(a) of the Patent Act, abandonment by lack of good faith reply, applies only during the prosecution of patent applications, and is no longer is relevant once a patent issues. Section 53(1) governs misrepresentation in issued patents.