On November 8, 2016, the Supreme Court of Canada heard oral arguments in AstraZeneca Canada Inc. et al. v. Apotex Inc. et al. The decision in this case may have important consequences for the validity of many patents, particularly those in the pharmaceutical field. The Supreme Court will get to decide whether the Federal Courts have been running amok in invalidating patents for lack of utility or whether they have been simply following the jurisprudence all along.

The case revolved around the so-called “promise doctrine”, which we previously discussed here. The Federal Court of Appeal had found that where a patent makes a promise of a particular result, utility will be measured against that promise. By applying this doctrine, the appellants’ (AstraZeneca Canada et al.) patent was found to be invalid.

A large portion of the oral arguments dealt with the relationship, if any, between claim construction and utility. The appellants argued that utility should be assessed as part of claim construction. As a result, individual claims may each have differing requirements for utility, depending on how each claim is construed (on a purposive construction). The appellants contended that the promise doctrine, as developed by the Federal Court of Appeal, was counter to established Supreme Court jurisprudence on claim construction.

Unsurprisingly, the respondents (Apotex Inc. et al.) argued that the Federal Court of Appeal (and the Federal Court) was correct in finding the patent to be invalid. Utility, they argued, is separate from claim construction. Instead, an assessment of utility requires that the whole of the specification be examined to determine what the invention is. Where, for example, a particular result is promised in the description, all claims will be held to that “promise”.

A subsidiary issue that was canvassed during oral arguments was the degree of utility required for an invention. One of the intervenors on the appeal (Innovative Medicines Canada and BIOTECanada) proposed that evidence of utility that postdated the filing date be admissible to show utility. This would be a departure from the current jurisprudence, which requires that utility be demonstrated or soundly predicted as of the filing date.

Some of the questions from the justices suggest that at least some of them may be uncomfortable with the potentially serious ramifications of the promise doctrine. At one point, Chief Justice McLachlin asked whether a patent should be found invalid because of potentially one overstatement in the specification. In another instance, Justice Abella questioned whether the trial judge’s parsing of the words in the patent (e.g. use of the word “will” versus “could”) was consistent with the notion of purposive construction.

Decision was reserved and is not expected for at least several months.