Case Comment
Tennessee Eastman Co. v. 
Commissioner of Patents          


citation(s): [1974] S.C.R. 111 at 116-117, 120

copyright 1997-2003 Donald M. Cameron, Ogivly Renault




The Decision

At p. 118

Section 41 was enacted for the purpose of restricting the scope of patents “relating to substances prepared or produced by chemical processes and intended for food or medicine”. The first principle proclaimed is that in the case of such inventions, “the specification itself, except when prepared or produced by the methods or processes of manufacture particularly described in the claim or by their obvious equivalents”. In my view, this necessarily implies that, with respect to such substances, the therapeutic use cannot be claimed by a process claim apart from the substance itself. Otherwise, it would mean that while the substance could not be claimed except when prepared by the patented process, its use however prepared could be claimed as a method of treatment. In other words, if a method of treatment consisting in the application of a new drug could be claimed as a process apart from the drug itself, then the inventor, by making such a process claim, would have an easy way out of the restriction in s. 41(1).

Having come to the conclusion that methods of medical treatment are not contemplated in the definition of “invention” as a kind of “process”, the same must, on the same basis, be true of a method of surgical treatment. In this connection, I would note that in Imperial Chemical Industries v. Commissioner of Patents ((1996), 33 Fox Pat. C. 153, 51 C.P.R. 102, [1967] 1 Ex.C.R. 57.), the Exchequer Court decided that an anaesthetic was a substance “intended for medicine” within the meaning of s. 41(1), relying on the decision of this Court in Parke Davis & Co. v. Fine Chemicals of Canada Ltd. ([1959] S.C.R. 219, 30 C.P.R. 59, 17 D.L.R. (3d) 153), in which it was held that the word “medicine” should be interpreted broadly so as to include the product in bulk as well as in dosage form.

At p.120

"In this decision, the Commissioner pointed out that the generality of the meaning of the word "art" in the definition of "invention" was effectively circumscribed, not only by s. 28(3) but also by other statutes such as the Design Act and the Copyright Act. This principle obviously applies equally to the construction of the word "process" with which we are concerned in this case. This is clearly what is being claimed as a "method". I can perceive no material difference between those two expressions in this context. In the Shorter Oxford English Dictionary, one of the definitions of "process" is "A particular method of operation in any manufacture". Similarly, in the Robert dictionary, one of the definitions of "procédé" (process) is [TRANSLATION] "Way in which an operation is performed. Means or method used or available for obtaining a given result".


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