Three recent Canadian Federal Court and Federal Court of Appeal decisions make reference to fundamentals of the patent system and all involve questions of validity of claims that are directed to either (i) a specific form of a known chemical molecule having distinct biological properties (so-called enantiomers, mirror images of the same molecule where each enantiomer can have significantly different biological activity); or (ii) a particular medical use of a known chemical compound [Janssen-Ortho v Novopharm (2007), Pfizer v Ranbaxy (2008); and Eli Lilly v Apotex (2008)].

In situations like these it is especially important to establish a clear understanding of the inventor's new and non-obvious contribution to the art as a background for claim interpretation. In the words of Justice Hughes in Eli Lilly v Apotex: "Information is to be gained from the patent as a whole in order to determine the context in which the claims are to be considered, and from experts whose role is to provide assistance, if necessary, in respect of the technical meaning of the terms and concepts used in the claims."

Following proper construction, it is then generally clear on the facts whether a claim is valid. This approach to claim interpretation and assessment of validity is also similar to the approach taken in the UK Court of Appeal decision Lundbeck v Generics (2008), where the issue was the scope to be given to a new, non-obvious enantiomer isolated from a known racemate. As Lord Hoffmann said: "One could read the claim as including the enantiomer when part of the racemate. But is this what the skilled person would have understood the patentee to mean?"

Mathias Dormann and Jennifer Holly

Marks & Clerk Canada
PO Box 957, Station B
Ottawa ON K1P 1C2
Canada
Tel: +1 613 236 9561
Fax: +1 613 230 8821
info@marks-clerk.ca 
www.marks-clerk.ca