Case Comment

B.V.D. Company Ltd v.
Canadian Celanese Ltd.

citation(s): [1936] S.C.R. 221 (per Davis, J.)

copyright 1997 Donald M. Cameron, Aird & Berlis




The Decision

At p. 233

"It may be stated as a general rule that the ambit of the invention must be circumscribed by definite claims. It is a question of law, then, whether or not the claims in this case read in the light of the specification may be limited. If they cannot, the claims remain so broad as to be invalid because of the prior art. If limited, they have not been anticipated. It is difficult to understand why the inventor in defining his claims in his British application should have expressly mentioned

"woven, knitted or other fabric composed of or containing filaments or fibers of a thermoplastic cellulose derivative or derivatives,

and in defining his claims in the United States application should have expressly mentioned

a fabric containing yarns comprising a thermoplastic derivative of cellulose

and should have entirely omitted such words in his subsequent application in Canada. Why do the claims omit what counsel for the respondent contended at the trial was the "new and all-important feature of the invention," namely, the use of the thermoplastic yarns of cellulose derivative woven into the fabric? We cannot say. Throughout the somewhat long specification there is a continuous reference to the use of the thermoplastic derivative of cellulose in the form of yarns, filaments or fibers and it is plainly the very essence of the disclosure in the specification. Why, then, was it left out of the claims? It may have been a slip of the draftsman or it may have been a deliberate omission in an effort to secure a wider field of protection than the disclosure warranted.

The Patent Act, 1923 (13-14 Geo. V, c.23) in force at the time of the application and grant of the patent expressly required by subsection (1) of section 14 thereof that the specification

"shall end with a claim or claims stating distinctly the things or combinations which the applicant regards as new and in which he claims an exclusive property and privilege."

At pp. 236-237

"In the Canadian patent involved in this appeal before us the inventor did not state in his claims the essential characteristic of his actual invention though it does appear in the claims in this British and United States patents. No explanation is offered. We are invited to read through the lengthy specification and import into the wide and general language of the claims that which is said to be the real inventive step disclosed. But the claims are unequivocal and complete upon their face. It is not necessary to resort to the context and as a matter of construction the claims do not import the context. In no proper sense can it be not mentioned in the claims the process defined in the claims necessarily possesses that essential feature. The Court cannot limit the claims by simply saying that the inventor must have meant that which he has described. The claims in fact go far beyond the invention. Upon that ground the patent is invalid.


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