The Federal Court of Canada recently dismissed a patent infringement action brought by McCain Foods against a competitor, Simplot.

McCain Foods alleged that Simplot’s use of pulsed electric field (PEF) technology to treat vegetables infringed its Canadian patent, which claims a process that applies a “high electric field” to vegetables to reduce their resistance to cutting.

The decision centered on the term “high electric field” in the claims. The Court applied the principles of claim construction and reviewed extensive expert opinions in order to conclude that the reference to “high electric field” in the claims referred to electric fields in the range of 2-200 V/cm. Since Simplot’s PEF technology, which operated at 1,000 V/cm or higher, did not fall within the 2-200 V/cm range, the Court found that Simplot did not infringe the patent.

Alternatively, the Court held that even if “high electric field” was interpreted broadly enough to encompass PEF technology, the relevant claims would be invalid for overbreadth and lack of utility. The Court found that McCain’s inventors had never disclosed or contemplated using PEF technology as part of their invention, and the patent failed to either demonstrate or soundly predict that PEF technology would be useful for the claimed purpose. The patent disclosure lacked the necessary factual basis and line of reasoning to establish the utility of the invention when applied to PEF technology.

This case is an important reminder of the principles of claim construction. The decision illustrates the challenges of extending a claim’s scope to cover a technology that may not have been contemplated or disclosed by the inventors at the time of patent filing.

A copy of the full decision is available here.