Case Comment

Diversified Products Corp. v.
Tye-Sil Companies Ltd.

citation(s): (1987),16 C.P.R. (3d) 207 per (F.C.T.D. Cullen J.)

copyright 1997 Donald M. Cameron, Aird & Berlis




The Decision

At p.229

"It is of great assistance to the plaintiff that both s. 47 of the Patent Act, R.S.C. 1970, c. P-4, and considerable case-law provide a presumption of the validity of a registered patent. The extent of this presumption is carefully enunciated by Thorson P. in Lovell Manufacturing Co. et al v. Beatty Bros. Ltd. (1962), 41 C.P.R. 18 at p. 44, 23 Fox Pat. C. 112...

The first reference to this statutory presumption of validity, or provision for prima facie validity, was in The King v. Uhlemann Optical Co., 11 C.P.R. 26 at p. 45, [1950] Ex. C.R. 142 at p. 161. Since then I have referred to it in several cases, the particulars of which were set out in McPhar Engineering Co. of Canada Ltd. v. Sharpe Instruments Ltd. (1960), 35 C.P.R. 105 at p. 128. There I referred to the comment which I had made in Unipak Cartons Ltd. v. Crown Zellerback Canada Ltd. (1960), 33 C.P.R. 1:

The statutory presumption is not confined to the attribute of inventiveness but extends to the other attributes that an invention must have if it is to be patentable under the Act, such as novelty and utility. The three attributes of patentability, namely, novelty, utility and inventiveness are all presumed to be present in an invention for which a patent has been granted until the contrary is clearly shown.'"

In the McPhar case I made a broader statement of the effect of the statutory provision. At p. 129, I said:

"On further consideration I am of the opinion that this statement is not as wide as the terms of the Act warrant. If must follow from the provision of the Act that a patent granted under it `shall thereafter be prima facie valid' and avail its grantee and his legal representatives for the term of the patent that the onus of showing that it is invalid lies on the person attacking it, no matter what the ground of attack may be, and that until it has been shown to be invalid the statutory presumption of its validity remains.

"This does not mean that the patent is immune from attack or that the patentee is free from the obligation that are incumbent on him by way of consideration for the grant of the patent monopoly to him, but it seems clear that, since Parliament has deliberately endowed a patent granted under the Act with a presumption of validity, the onus of showing that such a patent is invalid is not an easy one to discharge."


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