On November 23, 2009, the Canadian Federal Court publicly released its decision in Lundbeck v. ratiopharm, 2009 FC 1102, in which a patent was considered invalid for failure to respond in good faith to an Examiner's requisition.
The patent claimed a combination of two drugs. During prosecution, the Canadian Examiner noted that separate use of these drugs was known and rejected the combination as obvious. In response, the applicant referred to four prior art references in which similar combinations had reduced the effectiveness of one of the drugs and stated that "the prior art clearly teaches away from the [claimed] combination."
The response did not mention a fifth reference, an article by Wenk. The Wenk article was listed in the international search report of the corresponding PCT application and had been listed by the applicant in responding to an earlier requisition of the Examiner (under section 29 of our Patent Rules) to disclose prior art cited in respect of related foreign patent applications. The Court considered the Wenk article to have speculated at use of the claimed combination and to be more relevant than any of the four references referred to by the applicant in its response. On the other hand, the Court did not consider that the claims of the patent were anticipated or rendered obvious by the Wenk article.
Section 73 of our Patent Act provides that an "application for a patent in Canada shall be deemed to be abandoned if the applicant does not … reply in good faith to any requisition made by an examiner in connection with an examination" (emphasis added). The Court referenced this section and a previous decision that had considered it: G.D. Searle & Co. v. Novopharm Limited, 2007 FC 81. In Searle, a patent was considered invalid due to the applicant having presented arguments during prosecution that were inconsistent with an article that had been published by the applicant and was not brought to the attention of the Examiner. The Searle decision was overturned on appeal (2007 FCA 173). However, the Court in Lundbeck noted that this was only for the reason that the article was not properly considered to be prior art. The Court therefore considered the Searle decision to present an accurate overview of the obligations of the applicant and quoted the following language from that decision:
[C]ommunications with the examiner must be made in good faith. It is to be expected that there will be full, frank and fair disclosure. There is afforded during the prosecution ample opportunity to make further disclosure or to correct an earlier misstatement or shortcoming. It is not harsh or unreasonable, if after the patent issues, and disclosure is found to lack good faith, that the Court deems the application and thus the patent, to have been abandoned.
Moreover, the Court considered prosecution of a patent application to be analogous to an ex parte court proceeding wherein a party "must state his or her own case fairly and must inform the Court of any points of fact or law known to it which favour the other side." The Court held that the applicant's statement that the prior art "clearly teaches away from the [claimed] combination" was not a fair representation of the teachings of the prior art. The Court therefore concluded that the applicant had failed to reply in good faith to the requisition of the Examiner and held that the application, and thus the patent, should be deemed to be abandoned.
Several other recent Federal Court decisions have also relied upon the noted language in the Searle decision relating to the good faith requirement of section 73 of the Act. Some of these decisions are under appeal.
As a result, the extent of the good faith requirement in Canadian patent prosecution is currently uncertain. Therefore, the cautious approach is for an applicant to carefully "state his or her own case fairly" and to inform the Examiner "of any points of fact or law known to it" that are unfavourable to its position. If an applicant is aware of prior art that is more relevant than what is before the Examiner, it would be prudent to make such prior art of record during prosecution.