Case Comment

AlliedSignal Inc. v.
Du Pont Canada Inc., et al

citation(s): (1995), 61 C.P.R. (3d) 417 (F.C.A. per Desjardins J.A.)

copyright 1997 Donald M. Cameron, Cameron MacKendrick LLP




This is an appeal from a trial in an action for patent infringement reported at (1993) 50 C.P.R. (3d) 1 (F.C.T.D. per Reed J.) and (1994) 54 C.P.R. (3d) 351 (F.C.T.D. per Reed J.)

The Decision

A patent is to be construed as of the date it issued.

At p. 426:

“... a patent is to be construed at the date it is issued. Any doubt about such date is conclusively settled by reference to the French version of a statement made to that effect by Pigeon J. in Burton Parsons v. Hewlett-Packard [1976] 1 S.C.R. 555 at 560, where the words “la date de la delivrance du brevet” are used.2


2. The English version speaks about “the date of the patent”:

.. What must be ascertained is what the whole meant at the date of the patent to a person skilled in the art.

... Il nous faut determiner ce que le tout signifiait pour l’homme de l’art a la date de la delivrance du brevet.”

For the purpose of sufficiency of disclosure, the disclosure must give enough information to allow one to make the invention.

At p. 431:

“No evidence was adduced at trial that a person skilled in the art would not be able to prepare the film of the invention from the information contained in the patent specification and, accordingly, the specification was insufficient or ambiguous so far as the manufacture of the film was concerned. There may have been insufficiency as to the measurement of the crystallinity of the nylon 6,6 component of the film by the XRD. Reliability of the method of measurement, however, goes to infringement and not to the validity of the patent.”

What reasonable assumptions would a reader of the patent make to interpret the patent?

At p. 438-439:

“What the respondents and their experts contend is that the use of a value of FWHM of 5.9 gave Allied the answer it wanted but it is not scientifically legitimate. There are no publications or other references stating that a FWHM value is to be used to resolve the amorphous curve in determining the crystallinity of nylon 6,6. The appellant, they say, did not produce any document that stated that a FWMH value of 5.9 is to be used. No methodology is described. No document reports exactly how the numbers are to be determined.”

At p. 440:

“I also find that none of the articles submitted by Dr. Sibilia gives a definite figure for the FWMH in relation to nylon 6,6. Reference to the amorphous material as a basis for calculating the crystallinity of polymer can, however, be found in a number of articles...”

At p. 441-442:

“One is, therefore, tempted to query why Dr. Wilson, while making his numerous assumptions for the purpose of demonstrating that XRD was not reliable, never made one assumption using as a start the amorphous peak of molten nylon 6,6 which was used in the art at the time of the issuance of the patent. It is true that Dr. Wilson did not believe that XRD neither then, nor does he believe in it now, and that when questioned about the F.J. Balta-Calleja and C.G. Vonk paper, he acknowledged that “this is where reasonable people differ”. But others in the art used it and in, 1989, Dr. Murthy referred to it as “a definitive technique for estimating the degree of crystallinity in polymers.”

At p. 442-443:

“Had Dr. Wilson made a reasonable assumption with the FWHM of the amorphous peak of nylon 6,6 in the melt, and had he obtained a percentage of crystallinity above 35%, his experiment would have carried great weight in his demonstration that the method of measurement by XRD was unreliable. One would have thought that a person skilled in the art, at the relevant time (1984), would have used the method of measurement indicated in the patent, namely XRD, and would have made at least one assumption with molten polymer which, although not a perfect method, was in use at the relevant time. Ultimately, what is evidenced from the experts’ testimonies is that no method is absolute.

The appellant has established a prima facie case of infringment. The respondents could only discredit the appellant’s position by producing figures based on a reasonable scientific assumption as to the measurement of the FWHM. They failed to do so.

I can only conclude that, on the balance of probabilities, the appellant has made its case of infringement.”

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