Beware of What Your Canadian Patent Lawyer is Saying

Mar 02 2010

Recent case law has transformed Canada from a jurisdiction in which the file wrapper was not relevant to validity, to one in which the file wrapper is extremely important.

The United States has a well established duty of candour before its patent office. Decades of jurisprudence have established that a patent applicant and its agents must be forthright and candid with the USPTO.

In Canada, it was generally understood that the duty of candour was limited to an obligation to “reply in good faith to any requisition made by an examiner”. This requirement is found in s.73 of the “new” Patent Act, which addresses abandonment and reinstatement. It was generally understood that the phrase “good faith” was added to the Patent Act as a saving provision – if the applicant or its agent replied incorrectly (but “in good faith”) to a requisition, that would not be sufficient for an application to go abandoned. This is important because abandonment can have fatal effect in Canada. After the one year reinstatement period, an abandoned application or patent is finally, absolutely, and completely dead, regardless of the intentions of the applicant, and regardless of whether the applicant even knew the application was abandoned.

In G.D. Searle & Co. V. Novopharm Ltd. (2007 FC 81), Justice Hughes of the Federal Court found that the applicant had failed to disclose to the Patent Office that they had publicly disclosed the results of the tests on their claimed compound more than one year before filing. He held that this breached the “good faith” duty owed to the Patent Office under s. 73. This resulted in the retroactive abandonment of the application, thus the patent was dead. Justice Hughes held that the applicant had a duty to the Patent Office akin to the duty a litigant has to being candid when bringing an ex parte proceedings in court. As the proceeding is one-sided, the applicant had a high onus to present their position fairly and without bias. This finding appears to be contrary to the fact that there is no statute, rule, policy, or suggestion from the Patent Office that patentees have an obligation to disclose prior art, even their own, unless specifically requisitioned to do so by the Examiner. Further, this is somewhat inconsistent with a long history of jurisprudence that the validity of claims must be determined without reference to the file wrapper.

Justice Mactavish, also of the Federal Court, expanded on this duty of candour in Lundbeck Canada Inc. v. Ratiopharm inc. (2009 FC 1102). During prosecution of an application directed to a combination of drugs, the examiner cited a reference, “Wenk”, in an obviousness rejection. The applicant overcame that objection. The examiner raised a new obviousness objection, which the applicant also overcame, by arguing that the prior art taught away from the claimed combination. The applicant did not mention that Wenk stated that some combinations were effective while others were not.

Justice Mactavish followed the G.D. Searle finding there is a duty of candour akin to an ex parte proceeding, and held that the duty was not met, thus the patent application was abandoned and the patent was dead. The result is somewhat unusual in that Mactavish did not find that the Wenk article anticipated the claims or rendered them obvious, but failure to (again) draw the examiner’s attention to Wenk mischaracterized the prior art and thus breached the duty of candour.

For applicants, the lesson is that one must take extreme care in responding to examiners’ requisitions generally, and in characterizing the prior art in particular. Applicants should avoid general statements about the prior art, and should instead point to specific statements in the prior art. The applicant must take care to not mislead the examiner, even unintentionally.

For defendants, the lesson is that the file wrapper is a potential gold mine of patent busting material, and should be carefully scrutinized in considering patent validity.

The duty of candour owed by patent applicants has thus gone from almost non-existent to a high standard akin to ex parte proceedings. Unlike the US, which requires that any misdeed or mistake must be both material and intentional, Lundbeck indicates that there is no requirement that the breach be material (the Wenk article did not render the claims obvious or anticipated), nor does an inquiry need to be made into the applicant’s intention.

Canada appears to have transformed from a jurisdiction where the file wrapper is unimportant, to one where it is critical to validity.

This article is for information purposes only and does not constitute legal or professional advice.

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Tags: Federal Court, Patents, Prior Art