On 24th September 2013 the Federal Court of Appeal rendered its decision in the appeal and cross-appeal of Justice Martineau’s decision in Eurocopter v Bell Helicopter Textron Canada Ltée. Before the appeal court, Bell contended that the trial judge had made numerous errors of law and fact in finding that Eurocopter’s patent claim covering helicopter landing gear was valid. Further, Bell argued that the trial judge ought not to have awarded punitive damages. Eurocopter cross-appealed the trial judge’s finding that all but one claim of its patent were invalid for inutility.

While the appeal court dismissed the appeal and cross-appeal, its comments with respect to the issue of utility were of particular interest, as they dealt with the often controversial doctrine of sound prediction. After rejecting Eurocopter’s argument that this doctrine applied only to certain areas of technology (eg, pharmaceuticals), Justice Mainville went on to consider the disclosure requirement for sound prediction.

Mainville held that the degree of disclosure required of the factual basis and line of reasoning depended on the knowledge of the skilled person. If the factual basis and line of reasoning can be found in accepted scientific laws, principles or information that form part of the common general knowledge, they need not be disclosed. In other words:

"where the sound prediction is based on knowledge forming part of the common general knowledge and on a line of reasoning which would be apparent to the skilled person… the requirements of disclosure may readily be met by simply describing the invention in sufficient detail such that it can be practised."

Many patent holders will view this approach as a welcome departure from previous decisions of the federal courts, which had applied a much more rigid test for disclosure. Further, it is consistent with the way in which a patent is to be read for other purposes - namely, by the skilled person in light of the knowledge that they possess.

As a final point of interest, the court upheld the trial judge’s award of punitive damages against Bell. However, in doing so, it confirmed that punitive damages remain the exception rather than the rule, even in cases of intentional infringement. The court held that the guiding principle, as previously noted by the Supreme Court of Canada, is that punitive damages may be awarded when an accounting for profits or compensatory damages would be inadequate to achieve the objectives of retribution, deterrence and denunciation of such conduct.