Wednesday, August 21, 2013

The Duty to Disclose “The Invention”: The Wrong Tool for the Job

Teva Canada Ltd v Pfizer Canada Inc 2012 SCC 60
2,163,446 – Sildendafil – VIAGRA

My initial response to the SCC’s Sildenafil decision was quite positive about the general reasoning, though I was somewhat more critical of the doctrinal details of the decision. I have since completed a thorough analysis of the decision, which has caused me to substantially revise my opinion. In law, the doctrinal details matter, and in my article I argue that by using the wrong tool for the job, the SCC in Sildenafil did a poor job on the facts and damaged the tool of disclosure. My article, entitled “The Duty to Disclose ‘The Invention’: The Wrong Tool for the Job,” is forthcoming in the IPJ and is available in draft from SSRN. Here is the abstract:

In its Sildenafil decision, the Supreme Court of Canada held Pfizer’s Viagra patent to be invalid for failure to disclose “the invention,” though it provided no explicit definition of that term. I argue that on the best reading of the decision, “the invention” means the new, useful, non-obvious contribution to knowledge which is disclosed in the patent. While this is initially attractive, I argue that on this definition, a duty to disclose the invention is unsound as a matter of law and policy, because it implies that if any important claim in a patent is invalid, all the claims will be invalid. This eviscerates section 58 of the Patent Act, which provides that claims stand or fall independently. I argue that the Court’s reasoning was motivated by a mistaken belief that at the time of the application Pfizer had tested the other claimed compounds and knew them to be ineffective in treating ED, and that it claimed those compounds primarily to conceal the true invention. I argue that even if the Court’s understanding of the facts was correct, a duty to disclose the invention is not the appropriate tool to address the issue. The case properly raises questions relating to the duty of good faith disclosure, not a duty to disclose the invention.

My full analysis of the Sildenafil decision also confirms my initial view that Zinn J was wrong to grant summary judgment to Apotex in the subsequent impeachment action, Apotex v Pfizer / sildenafil 2012 FC 1339, in which he held the ‘446 patent to be of no force or effect, in part on the basis that “the determination by the Supreme Court in its Reasons that the '446 Patent fails to meet the requirement of sufficient disclosure pursuant to subsection 27(3) of the Patent Act is a legal determination binding on this Court and is dispositive of Apotex's claim in this action” [30]. While it is remarkably difficult to pin down precisely the core of the SCC’s legal reasoning in Sildenafil, the decision was clearly motivated by the belief that Pfizer had tried to “game” the system [Sildenafil 80; and see Imatinib 2013 FC 141, blogged here, in which Snider J at [387] emphasized this aspect of Sildenafil]. The SCC held this view because it apparently believed that Pfizer had tested the other compounds and knew them to lack utility. This is a factual question, and the SCC’s view appears to be wrong, in large part because the nature of the NOC proceedings did not allow the question to be fully explored. This illustrates the wisdom of the current rule that the results of NOC proceedings are not binding in a subsequent infringement or impeachment action. As the SCC said in Eli Lilly & Co v Novopharm Ltd [1998] 2 SCR 129, in affirming the rule developed in the Federal Courts (SCC’s emphasis):

[95] [T]he summary judicial review that is to be conducted on an application for a prohibition order under the Regulations is highly fact-specific and is generally considered to be binding only on the parties in the specific litigation. This is only appropriate, given the limited nature of the proceedings, the question that is to be answered, and the record generated for this limited purpose. [my emphasis]

[96] This point was reinforced more recently by Strayer J.A. in David Bull Laboratories, supra, at p. 600:
This Court is not prepared to accept that patentees and generic companies alike have been forced to make their sole assertion of their private rights through the summary procedure of a judicial review application. [SCC emphasis]

Note that in Eli Lilly v Novopharm the question on which the SCC refused to provide a binding declaration was whether the supply agreement constituted a sublicence. As a question of contractual interpretation, this would be a question of law, and despite having answered the question, the SCC refused to make a binding declaration, saying “For this Court to make a binding declaration concerning the private rights and obligations of the parties to the agreement would go well beyond the limited scope of the proceeding. Accordingly, I would deny the declarator relief requested by Novopharm” [97]. The same reasoning must surely hold with respect to the question of invalidity in Sildenafil, and for the same reason; my article on Sildenafil illustrates the perils of making a binding declaration based on the basis of the summary NOC proceeding.

1 comment:

  1. I would agree that it looks odd that “[t]he SCC held this view because it apparently believed that Pfizer had tested the other compounds and knew them to lack utility.” Apart from anything else, at their necessarily early stage of pharmaceutical research, how could Pfizer have proved the negative? Medicinal utility is an outcome that depends upon a complex mixture of pharmacokinetic and pharmacodynamic factors. In the jargon of the art, Pfizer had validated the therapeutic target, the PDE5 receptor, so that it was quickly apparent that a broad range of ligands would have physiologically relevant effects. Which of these ligands would make the best drugs was almost certainly an open question, and to some extent probably still is, but I don’t think that’s our standard for utility, and it shouldn’t be our standard for disclosure. Fundamentally, the invention wasn’t only a single compound. As a casual glance behind the counter at the local drugstore proves, it was a class of ligands that bound a validated target.