On May 29, 2013 Justice O’Reilly of the Federal Court dismissed Bayer PM Notice of Compliance (NOC) proceeding against Cobalt. The issue before the Court was whether Cobalt’s proposed generic product would infringe a single claim (claim 13) in a Canadian Bayer patent to drospirenone, an active ingredient in Bayer’s YASMIN contraceptive. The Court determined that Cobalt’s non-infringement allegation was justified. For the full written decision see: Bayer Inc. v. Cobalt Pharmaceuticals Company 2013 FC 573.

Nature of the Claim

The claim covered a product “prepared according to the process of claim 12, wherein the product comprises drospirenone and less than 0.2%” of contaminants identified in claim 12. Bayer contended that claim 13 is a pure product claim. Cobalt argued it was a product-by-process claim (i.e., a claim to a product when made by a particular process). Presumably Bayer pursued the former construction as Cobalt allegedly did not use the process of claim 12.

Bayer’s argument was, in part, based upon its reading of a relatively old and famous case called Hoffman-LaRoche & Co. v. Commissioner of Patents, [1955] SCR 414. The decision is often referred to for the proposition that a product-by-process claim is invalid if the product is old, despite novel development processes.

Bayer argued the upshot of Hoffman-LaRoche for product-by-process claims must be that the process aspect of the claim is essentially ignored, whether it be for the purposes of a validity or an infringement analysis. The Court disagreed with Bayer’s reading and held that “product-by-process claims should not always be read without reference to the specified process.” That statement seems imply that there are situation or circumstances in which the process aspect is to be ignored. In the end, the Court found Cobalt’s allegation justified — it would not use the complete process aspect of claim 13 to make drospirenone.

Remaining Issues

This decision highlights without resolving the apparent problem provided by Hoffman-LaRoche under current principles of Canadian patent law. This problem has been the subject of doubtful comment in other Federal Court decisions. For example, in Merck & Co. Inc. v. Apotex Inc. 2010 FC 1265 at paragraph 578 the Court states:

I admit to having considerable difficulty in understanding how the conclusion in Hoffmann-LaRoche 1955 can fit with the protection offered by the Patent Act. It seems illogical to me that a process for making a substance can be novel and thus patentable but that a claim for the product when made by that process is automatically not patentable.

There appears to be an irreconcilable inconsistency. How can it be that the essential process element of a product-by-process claim be necessarily present for infringement, but irrelevant to validity? This is especially so when processes themselves can be patentable subject matter in Canada.


The clarification of Hoffman-LaRoche may have to be left for another day. Given that Cobalt has defeated what appears to be the only patent listed on the Patent Register for YASMIN, its marketing approval may be imminent. If granted, there may never be an appeal ruling in this case.