One of the most current topics in Canadian patent litigation is
whether there is a general duty of good faith during the course of
patent prosecution, and if so, whether a breach of that duty is a
ground for invalidating a patent. In Corlac Inc. v. Weatherford
Canada Ltd.1 the Federal Court of Appeal has ruled
that any lack of good faith in responding to an office action will
not invalidate a patent in a subsequent court proceeding. It is for
the Commissioner of Patents to determine if an applicant has
responded in good faith, not the courts.
Section 73 of the Patent Act includes an obligation to
reply in good faith to any office action. If a reply is not made in
good faith, the consequence is a deemed abandonment of the
In 2009, a decision of the Federal Court in Lundbeck Canada
Inc. v. Ratiopharm Inc.2 invalidated an issued
patent because the applicant failed to respond to an office action
in good faith. When responding to an office action, Lundbeck's
patent agents provided the examiner with four prior art references
and argued that they "taught away" from the invention.
Lundbeck's agents did not mention another prior art reference
in the file which contained a directly relevant study that came to
the opposite conclusion. Justice MacTavish compared patent
prosecution to an ex parte court proceeding. A party
seeking ex parte relief has the duty of ensuring that the
court is apprised of all of the relevant facts, and must do more
than simply present its own case in the best possible light, as
would be the case if the other side were present. Like an ex
parte litigant, patent applicants must state their case fairly
and raise any points of fact or law known to it which favour the
other side. Having failed to mention the article, Justice MacTavish
determined that Lundbeck failed to reply in good faith to the
office action. The patent was held invalid. Many defendants in
patent actions began combing through file histories, particularly
office action responses, to raise invalidity defences based on a
lack of good faith.
Weatherford was the first opportunity for the Court of
Appeal to squarely consider whether a patent may be invalidated
because of a demonstrated lack of good faith in responding to an
The Court determined that Lundbeck should not be
followed; section 73 only applies during prosecution of the patent
application. The operation of this section is extinguished once the
patent issues. If there was a lack of good faith in responding to
an office action, that is for the Commissioner of Patents to
determine, not the courts. A defendant in a later infringement
action cannot raise a lack of good faith in responding to an office
action as a ground of invalidity.
Section 53 of the Patent Act provides that an issued
patent may be held invalid if a material allegation in the petition
is untrue. (The petition is a one-page document listing the
applicant, inventors and the identity of the agent; it does not set
out the substance of the invention). This was also an issue in
Weatherford as the named inventor, Grenke, had filed a
request to remove the name of a co-inventor, Torfs. It was
determined that Grenke did this not only because he had acquired
all of the rights through assignments, but because Torfs had
"cut him out" of other patents. While this was a
misstatement, it was not found to be material. The patent was not
invalidated because Torfs was removed as an inventor.
The Weatherford decision will no doubt come as a relief
to Canadian patent agents, whose past office action responses will
no longer be subject to scrutiny when the validity of a patent is
challenged. It is also expected that parties will pay closer
attention to the patent filings of their competitors and, where
appropriate, attempt to file protests to raise allegations of lack
of good faith in responding to an office action while applications
are still pending.
1 2011 FCA 228
2 2009 FC 1102
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A recent Saskatchewan Court of Queen's Bench decision allowed a court-appointed receiver to sell and transfer intellectual property rights free and clear of encumbrances, finding that a license to use improvements of an invention was a contractual interest and not a property interest.
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