Nycomed’s ‘748 patent claims a combination of pantoprazole with a heliobacter inhibiting anti-microbial agent. Apotex and Novopharm sell generic pantoprazole. Since the ‘748 patent does not claim pantoprazole itself, Nycomed sought to allege that the generics’ sale of pantoprazole constitutes contributory infringement. The theory is that pharmacists and physicians who dispense or prescribe pantoprazole and an anti-microbial agent are direct infringers, and the generics have “contributed to the infringing activities of these third parties through its product monograph, website and its marketing strategies to physicians and pharmacists” [FC 2].
The factual problem for Nycomed is that the combination of an antibiotic with a proton pump inhibitor (PPI), such as pantoprazole, is now the “gold standard” for the treatment of ulcers caused by H pylori (see 2006 FC 1411 at ), so it is very likely that substantial infringement would occur regardless of the generics’ marketing. Nycomed therefore sought to allege that the generics were liable for contributory infringement “distinct from the ‘but for’ allegation of inducement” [FC 2].
The legal problem with this claim is that contributory infringement is not recognized as such in Canadian law. As the FCA stated in Beloit Canada Ltee/Ltd et al v Valmet Oy (1988) 20 CPR(3d) 1 (FCA) (citations omitted):
Moreover, it is well established that there is no infringement of a patent in selling an article which does not in itself infringe the patent even when the vendor knows that the purchaser buys the article for the purpose of using it in the infringement of the patent. There seems to be only two exceptions to that rule, namely, that there is infringement:
(a) if the vendor, alone or in association with another person, sells all the components of the invention to a purchaser in order that they be assembled by him; and
(b) if the vendor, knowingly and for his own ends and benefit, induces or procures the purchaser to infringe the patent.
The second branch, inducement, is defined by the following three part test, set out most recently in Corlac v Weatherford 2011 FCA 228 at :
First, the act of infringement must have been completed by the direct infringer.
Second, the completion of the acts of infringement must be influenced by the acts of the alleged inducer to the point that, without the influence, direct infringement would not take place.
Third, the influence must knowingly be exercised by the inducer, that is, the inducer knows that this influence will result in the completion of the act of infringement.
The second part amounts to a requirement that the direct infringement would not have taken place “but for” the acts of the alleged inducer.
Consequently, Simpson J held that Nycomed could not amend its claim to allege contributory inducement distinct from the “but for” allegation of inducement. Nycomed argued that the SCC decision in Monsanto v Schmeiser, 2004 SCC 34 had changed the law. Simpson J disagreed, and the FCA affirmed, saying “we adopt the reasoning set out at paragraph 27 of her reasons for holding that the decision of the Supreme Court in Monsanto Canada Inc. v. Schmeiser, 2004 SCC 34, is not indicative of an intention to depart from the existing precedents and to recognize 'contributory infringement' as a cause of action under the Canadian law.” My own view is also that Simpson J’s interpretation of Schmeiser was entirely correct.
There is nonetheless a problem in this kind situation, at least in principle. Assume that the physicians are directly infringing, as alleged. Suppose that most would have infringed in any event, but in a substantial minority of cases, say 40%, the generics were the “but for” cause of the direct infringement. In that case Nycomed would not be able to establish “but for” causation for physicians as a class, even though the generics marketing efforts were the “but for” cause of a substantial loss.
This is exactly the problem of mass torts, which was addressed at common law by permitting liability based on “material contribution” rather than but for causation: see McGhee v National Coal Board  3 All ER 1008 (HL). This solution is very unsatisfactory, as it raises the opposite problem, that the defendant might be liable for all the loss, even though it was only the “but for” cause of a part. Material contribution is consequently disfavoured: see, most recently, Clements v. Clements, 2012 SCC 32. In refusing to relax the causation requirement for contributory infringement to something approaching material contribution, the FCA holding in this case is consistent with this general trend. The problem is solved more satisfactorily by class actions, in which the defendant can be made liable for only the proportion of the harm that it actually caused. I am not suggesting that a class action would be appropriate in this case. Class actions allow a class of plaintiffs to sue a single defendant for what might be called “contributory” causation, rather than allowing a single plaintiff to sue a class of defendants, and in any event, Nycomed wants to sue the generics, not the doctors. The point is simply that there is a real problem in principle which is not satisfactorily addressed by “but for” causation.
At another level, the problem is that the only practical means of enforcing the patent at issue in this case, or a use patent, as was at issue in Abbott / lansoprazole (NOC) 2006 FC 1411 aff’d 2007 FCA 251, is by an action against the generic, and yet the generic is entitled to sell the individual compound. I can’t help but think that there must be a better way of sorting this out than disputing over whether 40% or 60% of doctors would be influenced by the product monograph, but I have to admit that I can’t think of what that better way might be.