This January Canada’s Federal Court of Appeal in Canmar Foods Ltd. v. TA Foods Ltd., 2021 FCA 7 affirmed a decision dismissing a patent infringement action for a lack of infringement on a motion by the defendant for summary judgment (see here for the decision on the motion). While recent years have seen several other examples of successful motions for summary judgment in patent cases (see here, here, and here), such motions have historically been rare. Accordingly, a decision of the Federal Court of Appeal affirming a summary judgment in a patent case is significant and lends support to the idea that the Federal Court has become more receptive to such motions. Litigants in patent and other intellectual property matters should give serious thought to summary judgment motions as part of their litigation strategy where they think they have a strong position and there is no genuine issue for trial. 

Some key issues considered by Court of Appeal in reaching its decision were as follows.

Section 53.1 of the Patent Act

Admissibility of statements made during prosecution of foreign patents

Summary judgments aside, the decision is significant for its consideration of section 53.1 of the Patent Act. This section enacted a form of file wrapper estoppel when it came into force in 2018. Prior to that, statements made in the Patent Office (or, for that matter, anywhere other than in the issued patent) were not admissible in Canadian courts on the issue of claim construction. This prohibition created a risk that a patentee would try to construe claims in an issued patent in such a way so as to recapture subject-matter that the patentee had, in order to have the patent issued, previously given up during prosecution. Indeed, on a few occasions the Federal Court expressed a level of unease with not being able to consider the prosecution history when determining the scope of protection offered by a patent.

The law changed when section 53.1 was added to the Patent Act. The section states that written communications between the applicant and the Canadian Patent Office may be admitted into evidence in a proceeding to rebut any representations made by the patentee as to the construction of a patent claim.

The issue on this appeal was whether statements made in a foreign patent office fall under the section 53.1. The defendant successfully argued on the motion that certain statements made to the US Patent Office fell under section 53.1 because they were incorporated by reference into the Canadian prosecution. More specifically, at issue was the construction of two elements (which the defendant argued made the claims sufficiently narrow so as to not capture its devices) that were added to a set of claims in a related US application. Similar claims that included the same two limitations were filed with the Canadian Patent Office and made their way into the issued Canadian patent. When submitting the claims, the applicant wrote to the Canadian Patent Office that the claims “correspond substantially to those submitted during prosecution of a related United States application”, that the “newly submitted claims are much narrower in scope than previously examined claims in view of the introduction of significant limitations”, and further that the “new claims are submitted to encompass both novel and non-obvious subject-matter”.

Notably, the US application was amended to avoid a prior art patent which appeared to be for the device that the plaintiff alleged to be infringing. The plaintiff also appears to have admitted that the amendments limited the scope of the claims to overcome obviousness and novelty concerns of the type raised by the US Patent Office. In view of the evidence, the motions judge agreed that statements made to the US Patent Office were admissible on the issue of construction under section 53.1.

The Court of Appeal disagreed that the statements were admissible in this case. It cautioned that the courts should be wary to extend the detailed language of section 53.1, which explicitly specifies that the admissible communications are those with the Canadian Patent Office. Opening the door to allowing foreign patent prosecution history, the Court noted, might lead to overly contentious and expensive litigation. However, the Court of Appeal recognized that one should not underplay the public interest in keeping those who have previously disclaimed elements from their patents from re-claiming them in future infringement cases.

In the end, with respect to the broader issue of whether the prosecution history of a foreign application can ever be considered under section 53.1, as a result of incorporation by reference or otherwise, the Court of Appeal “wished to express no firm views on the matter”. However, in regard the specific appeal, the Court of Appeal concluded that the facts of the case did not lend themselves to a proper finding of incorporation by reference, as the communication with the Canadian Patent Office did not identify with any level of particularity what specific communications with the US Patent Office were being incorporated. 

Nonetheless, the Court of Appeal agreed with the motions judge on the issue of claim construction for other reasons.

Section 53.1 triggering event: specific rebuttal or claims construction generally

During its analysis of the issue of statements made to foreign patent offices, the Court of Appeal also touched on the purpose for which communications with the Patent Office can be introduced under section 53.1. Two lines of authority, the Court noted, have developed in the case law. In Eli Lilly Canada Inc. v. Apotex Inc., 2020 FC 814, the court adopted a more restrictive interpretation, namely that the purpose is the rebuttal of an identifiable representation by the patentee in regard to construction of a claim. On the other hand, in Bauer Hockey Ltd. v. Sport Maska Inc., 2020 FC 624, the court adopted a more permissive approach in holding that prosecution history is admissible whenever claim construction is at issue, with the emphasis being not so much on a rebuttal, but rather on the interpretive process itself. While the Court of Appeal left the resolution of this tension for another day, given that the Court noted elsewhere in its decision that “courts should be wary to extend the detailed language of section 53.1”, it may be that the better view is that the Court of Appeal would prefer the more restrictive reading of section 53.1 should this issue come before it.

 
Discovery does not have to happen before a motion for summary judgment

Another issue on the appeal was whether discovery should have taken place before the motion for summary judgment. The defendant brought the motion immediately after filing its defense. No discovery took place. The defendant provided evidence about its technology on the motion by way of an affidavit, but the plaintiff was not granted access to the defendant’s facilities. On appeal, the plaintiff argued that it should have been given a chance to discover the defendant. The Court of Appeal disagreed, noting that the rule governing motions for summary judgment does not require that discovery take place, and that the plaintiff could have, but chose not to file evidence available to it, including expert evidence. 

Absence of expert evidence not fatal on a motion for summary judgment

Speaking of expert evidence, an interesting feature of this case was that neither party produced expert evidence on the motion for summary judgment. The appellant argued consequently that it was an error for the court to construe the claims without the aid of expert evidence. The Court of Appeal rejected this argument, noting that the plaintiff could not make this argument having itself failed to lead any expert evidence, and noting further that after all, it was up to the court to construe the claims. The Court of Appeal cautioned, however, that “it is only in the clearest of cases that judges should feel confident enough to construe the claims of a patent as they would be understood by a skilled person, without the help of any expert evidence”.

Experimental testing versus a demonstration run

Finally, the defendant’s evidence on the summary judgment motion included evidence about the operation of the defendant’s device. The plaintiff argued that this evidence was based on experimental testing to which it should have been invited, as required by the Federal Court Notice to the Profession re: Experimental Testing. The Court of Appeal rejected this argument, agreeing with the motions judge that the respondent did not run an experimental test, but rather conducted a demonstration run in the normal course of commercial production, and the witness was merely measuring the temperature during production runs. It will be interesting to see whether this distinction will be utilized by litigants in future cases.