The Date For Assessing Disclosure Sufficiency ' Is This An Open Issue?

• Published date: 07 September 2022
• Subject Matter: Intellectual Property, Patent
• Law Firm: Aird & McBurney LP
• Author: Steve Hundal, B.Eng.

Overview

Recently, the Federal Court of Appeal released its decision in Pharmascience Inc. v. Bristol-Myers Squibb Canada Co., 2022 2022 FCA 142 142 (the "Decision"). The Decision touches on various issues, but I want to focus on one: the relevant date for assessing disclosure sufficiency.

The Decision results from consolidated appeals of Zinn J.'s decision in Bristol-Myers Squibb v. Pharmascience and Sandoz, 2021 2021 FC 1 1, which found Canadian Patent nos. 2,461,202 ("the '202 patent") and 2,791,171 ("the '171 patent"), Bristol-Myers Squibb's patents for apixaban, to be valid. The '202 patent claims the compound apixaban and its use in treating thromboembolic disorders (e.g., stroke), and the '171 patent claims formulations of apixaban. Below, I discuss the disclosure sufficiency attack on the '202 patent.

Previously, the Federal Court of Appeal, in Idenix Pharmaceuticals, Inc. v. Gilead Pharmasset LLC., 20172017 FCA 161 FCA 161 ("Idenix"), held that the filing date is the relevant date for assessing disclosure sufficiency:

Since the filing date, all three synthesis pathways... have been proven to work.... According to Idenix, this fact supports the sufficiency of its disclosure because no matter which pathway the skilled person chose, they would arrive at the Claimed Compound [a compound claimed in the issued patent]. Though reversed on other points, this Court held in Novopharm Limited v. Pfizer Canada Inc., 2010 FCA 242 at paragraph 79, [2012] 2 F.C.R. 69, that courts must "determine whether the disclosure was sufficient as of the date of filing. As a result, anything which occurred subsequent thereto is of no relevance." In my view, Idenix's argument reflects the benefit of hindsight rather than the knowledge of the skilled person at the relevant date. (Idenix, [46]; commentary in square brackets, emphasis added)

Generally, when we assess the validity of a patent, we of course are considering the patent's specification as issued; not as filed, nor as published. After all, we can only invalidate a patent, and not a pending application for one. So then, what exactly do we mean when we say that a disclosure's sufficiency is assessed as of the filing date? There are other factors, outside of the scope of the issued specification, that come into play in assessing disclosure sufficiency; the assessment is made from the perspective of the person of skill in the relevant art, in view of the common general knowledge in the art as of the relevant date...