Canada: Federal Court Of Appeal Affirms Invalidity Of All But A Single Claim For Failure To Meet Promises In A Mechanical Patent

Last Updated: October 10 2013
Article by Ronald D. Faggetter

In the 2012 decision of Eurocopter v Bell Helicopter Textron Canada Limiteé, 2012 FC 113, Canada's Federal Court invalidated all but one claim of a patent for helicopter landing gear on the basis that the invalidated claims encompassed an embodiment that failed to achieve the utility promised in the patent. In a recently released appeal of that decision — Bell Helicopter Textron Canada Limiteé v Eurocopter ("Eurocopter"), 2013 FCA 219 — Canada's Federal Court of Appeal has upheld this invalidity ruling.

Promised utility. Canada's Patent Act, similar to the legislation in many other countries, provides that an invention must be useful to be patentable. If a claimed invention is inoperable, then the claim is invalid.

Canadian courts, in interpreting the requirement for utility, have considered that if a patent promises a particular utility for an invention, the invention must achieve this promised utility to avoid invalidity of claims directed to the invention. Thus, while there is no requirement to promise a specific utility, if a promise is made, the question of whether the invention has utility has been assessed by reference to the explicit promise.

In Eurocopter, the specification of the patent disclosed embodiments where the landing gear had a forward offset cross-piece and a further embodiment where this cross-piece had a backward offset. The specification stated that the landing gear reduced the problem of ground resonance (potentially dangerous vibrations that can occur on landing). This statement in the specification was considered by the Court to be a promised utility for all of the embodiments of the invention.

Sound prediction. Where there is an explicit promise, utility is established if the promised utility is demonstrated by the date of filing the patent application or if the promised utility is soundly predicted as of the filing date. A sound prediction is shown if (1) there is a factual basis for the prediction; (2) the inventor has a sound line of reasoning from which the desired result can be inferred from the factual basis; and (3) there is proper disclosure.

The patentee, Eurocopter, submitted that the doctrine of sound prediction was developed in the context of patents in the pharmaceutical field and argued that the inherent uncertainty of results in chemistry and biology had led to development of this doctrine. The patentee concluded from this that the doctrine of sound prediction should not apply to mechanical inventions, where there is no such inherent unpredictability.

Further, while the patentee admitted that it had never made the backward offset landing gear, it argued that it had nevertheless demonstrated utility of this landing gear as of the date of the patent application with mathematical models.

The Federal Court of Appeal disagreed with the patentee and held that the doctrine of sound prediction can apply to the field of mechanical inventions.

Regarding the mathematical models, the Court opined that "calculations and mathematical modeling are, by their very essence, a prediction of a given utility" and not a demonstration of utility. Thus, the patentee had to show the three requirements for a sound prediction.

Regarding the requirement for a factual basis, the Court stated:

Where the factual basis can be found in scientifically accepted laws or principles ... no disclosure of such factual basis may be required in the specification. On the other hand, where the factual basis is reliant on data which does not form part of the common general knowledge, then disclosure in the specification may indeed be required ...

Regarding the requirement for a sound line of reasoning, the Court noted that the soundness of the reasoning can be assessed by asking whether a skilled person would accept the logic presented in the specification.

The Court then stated that "where the sound prediction is based on ... common general knowledge and on a line of reasoning ... apparent to the skilled person (which is often the case with mechanical inventions), the requirements of disclosure" — that is, the third requirement for sound prediction — "may readily be met by simply describing the invention in sufficient detail such that it can be practiced."

The Court noted that Eurocopter had no explanation in the patent relating to the promised effect of reduced ground resonance for the backward offset embodiment. The Court then stated "Eurocopter did not provide evidence that it had either demonstrated or soundly predicted the utility of the backward inclination embodiment prior to [the filing date]. Eurocopter did not do so in the patent specification and it failed to do so at trial." The Court therefore upheld the invalidity of the claims covering this embodiment.

The Eurocopter decision is another step in the evolution of the sound prediction doctrine. The Eurocopter decision highlights the need for caution in Canada in making promises in a patent specification as to the utility of any invention.

Punitive Damages. The decision is also notable for the damages award. The Federal Court of Appeal upheld the punitive damages award for infringement by Bell Helicopter of the valid claim. Punitive damages are rarely awarded in patent cases. The award was considered appropriate in this case in view of Bell Helicopter's misappropriation of the invention as its own, and since an accounting of profits and compensatory damages were considered inappropriate to adequately deter similar conduct in the future.

Within sixty days after the date of the decision of the Federal Court of Appeal in Eurocopter, either party could seek leave to appeal to the Supreme Court of Canada.

The preceding is intended as a timely update on Canadian intellectual property and technology law. The content is informational only and does not constitute legal or professional advice. To obtain such advice, please communicate with our offices directly.

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Ronald D. Faggetter
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