Not Replying In Good Faith During Prosecution Not A Ground For Patent Invalidation Under Subsection 73(1)(a) of The Patent Act

Published August 11th, 2011

     On July 18, 2011 Canada’s Federal Court of Appeal (FCA) delivered a unanimous decision in the case of Corlac Inc. v. Weatherford Canada Ltd. (2011 FCA 228).

     What will be of particular interest to applicants, and to those who prepare, file and prosecute patents on their behalf, is the FCA’s determination that Subsection 73(1)(a) of the Patent Act – requiring the patent applicant to reply in good faith to all requisitions made by an Examiner lest the application be deemed abandoned –  cannot be used to invalidate a patent once it has issued.  This is simply because the Subsection specifically refers to a patent application and not to a patent.  

     The FCA stated that it is Subsection 53(1) of the Patent Act that speaks to misrepresentations in relation to patents, while Subsection 73(1)(a) speaks to good faith in the prosecution of the patent application to regulate the process, and that the two Subsections are mutually exclusive. 

     The FCA agreed with the Federal Court (FC)’s finding that one of the inventors had untruthfully alleged that an originally-named co-inventor was not in fact an inventor, when amending the petition.

     However, the court stated that “to the extent that the Federal Court decisions in G.D. Searle (2007 FC 81) and Lundbeck (2009 FC 1102) can be interpreted as standing for the proposition that paragraph 73(1)(a) can be relied upon for the purpose of attacking the validity of a patent, they should not be followed”.  Thus, it did not matter whether or not removal of the co-inventor was made in good faith, since in this case doing so did not constitute a ground for invalidating an issued patent under Subsection 73(1)(a).

     Furthermore, in assessing whether removing the co-inventor invalidated the patent under Subsection 53(1) of the Patent Act, the FCA stated that an untrue material allegation in the petition will not render a patent void unless it was wilfully made for the purpose of misleading (see Alberta Inc. v Q’Max Solutions 2003 FCA 241).  The FCA found that removal of the co-inventor from the petition in this case was not an act wilfully made for the purpose of misleading.  In fact, the FCA found that, in this case, removal of the co-inventor from the petition, while an untrue allegation, was not material.  In finding that the removal was not material, the FCA agreed with the FC that the notion of materiality is a fact-specific determination, and that inventorship is not material in all circumstances. 

     The FCA noted that the American cases raised by the appellant as examples in support of invalidating a patent for inequitable conduct only served to highlight the problems associated with an ever-expanding doctrine of inequitable conduct in the USA.  The FCA also noted that the United States Court of Appeals for the Federal Circuit (CAFC) had itself recently found it necessary to tighten the inequitable conduct standard “in order to redirect a doctrine that has been overused to the detriment of the public” (see Therasense, Inc. v. Becton, Dickinson and Company, Appeal No. 2008-1511).

     The FCA also reviewed the FC’s considerations as to patent anticipation and obviousness.  Regarding anticipation, the FCA was asked to consider the implications of two sales of prototypes which occurred more than a year before the application filing date, one to Amoco and one to Pan Canadian.  As to the Amoco sale, the FCA found that the FC made no palpable and overriding error in finding that the patentee shared a common cause and had a relationship of trust and co-operation with Amoco that led to an expectation of confidence.  Thus, the Amoco sale was not considered to be an anticipatory disclosure to the public.

     As to the Pan Canadian sale, despite concluding that there was no evidence to support a relationship of trust and co-operation between the patentee and Pan Canadian, the FCA agreed that the evidence supports the FC’s conclusion that the prototypes were test units and subject to a general industry practice of confidentiality.

     The FCA therefore found that no anticipatory disclosure had been made due to either of the sales.

     As to obviousness, the FCA noted that the FC did not explicitly follow the four-step approach for assessing whether a claimed invention is obvious, as outlined in Sanofi (Apotex Inc. v. Sanofi‑Synthelabo Canada Inc. 2008 SCC 61).  However, the FCA noted that the Sanofi test is not in fact a compulsory legal test.  Rather, it is but a helpful tool, and failure to follow it does not, in itself, constitute an error in law.  Further to this, the FCA found no overriding error in the FC’s obviousness analysis that would merit its intervention.

     The FCA did return the question of inducement of infringement of a method claim back to the FC for reconsideration, having found that the FC analysis in this regard was deficient and should be determined with the established three-prong test as set out in MacLennan v. Les Produits Gilbert Inc. 2008 FCA 35.

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