Whether south or north of the US-Canada border, the proper
standard of review of patent claim construction sometimes,
especially in complex cases, can be problematic. South of the
border, a recent decision of the Supreme Court of the United States
signals a growing acceptance that deference should be accorded to
the interpretation of patents reached by those who have seen
experts and evaluated them: Teva Pharmaceuticals USA v
Sandoz, 574 US __ (2015).
This observation was also made north of the border, in a recent
appeal to the Canadian Federal Court of Appeal. In Cobalt
Pharmaceuticals Company v Bayer, 2015 FCA 116, the Court of
Appeal considered the standard of review on claim construction. The
Court acknowledged that, as the law currently stands in Canada,
claim construction is to be reviewed on a standard of correctness
as it is a question of law (and so no deference is given to the
lower court's construction). The assessment of expert evidence
on a matter of fact is reviewed on a deferential standard (meaning
the assessment by the lower court is overturned only if it contains
a palpable and overriding error).
However, the Court of Appeal further noted in passing that,
"Often the experts' testimony stretches beyond opinion
evidence and goes into factual matters within their knowledge that
are relevant to the construction exercise". The Court asked,
"Can appellate judges really second-guess the trial judge,
who, often over many days, has been educated in the relevant art
and has seen and evaluated the experts? Who are the appellate
judges to review on the basis of correctness, stepping into the
shoes of the trial judge and imposing their own views of the
matter?"
As noted by the Supreme Court of Canada, the inventor is
addressing others in the same line of work. However, words have
layers of significance and secondary meanings. The word
"bench", for example, means a physical object to
weight-lifters but has numerous secondary meanings for members of
the legal profession.
The Court of Appeal suggested that claim construction cannot
reasonably be a "pure" question of law that is reviewable
on a non-deferential standard – except for an extricable
legal question, which is reviewed for correctness. Rather, the
Court suggested that interpretations of the specification should be
reviewed on a deferential standard when they are heavily dependent
on expert testimony.
The Court of Appeal invited the Supreme Court of Canada to provide
guidance on the standard of review on claim construction. Leave to
appeal to the Supreme Court of Canada was not sought though.
However, the Cobalt decision leaves the door open. In
future cases where claim construction is disputed, parties may
seize the opportunity to ask the Supreme Court to revisit the issue
of standard of review on claim construction.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
