Case Comment

Control Data Canada Ltd. v. Senstar Corporation


citation(s (1989), 23 C.P.R. (3d) 449 (F.C.T.D. per Cullen J.)

copyright 1997-2007 Donald M. Cameron




The Decision

At pp. 464-465:

The suggestion that the work being performed by Beal made the patent in suit obvious, or was in fact prior art, is questionable. Beal himself and his colleagues who were working with the only leaky coaxial cable saw the invention as novel, an "elegant solution to the problems encountered by other". There is not the hint of suggestion that Beal felt his work and effort had been usurped by Harman or that his ideas had been used to buttress the patent, quite the opposite in fact, and as late as the trial date, even with the assistance of hindsight, is still able to say, "I am certain I would not have thought of using two leaky coaxial cables, one attached to a transmitter and the other attached to a receiver as was done by Dr. Harman in the Patent" (para. 19 of Beal’s affidavit) (emphasis added).

The expertise of Beal in this area is unquestioned and he, along with others, was actually working on "intruder detection". The other engineers working hand-in-glove with Beal and each other suggested a solution pointing in a completely different direction.

The situation that arose in this case is not unlike most cases namely, the expert witnesses for the plaintiff say the invention is not obvious and expert witnesses for the defendant say it is. Here, however, one of the plaintiff’s expert witnesses was actually working on the problem of intruder detection, namely, Beal.

In Windsurfing Int’l Inc. v. Trilantic Corp. (1985), 8 C.P.R. (3d) 241, a decision of the Federal Court of Appeal, Urie J. was commenting on the fact that the trial judge preferred the evidence of the expert for the defendant over that of the expert for the plaintiff to hold a patent invalid. A new name in patent law surfaced with this case, Mr. Newman Darby (Darby). At the bottom of p. 259, Urie J. states, after he repeats an exchange from cross-examination of Darby and what he had done with his sailboard up to the time of the invention of the windsurfers:

From all of this I can only conclude that as at the date of the invention in suit, August 20, 1967, the advantages inherent in the use of a Marconi rig so obvious to Mr. Herreshoff [expert witness for the defendant] were not so obvious to Mr. Darby [who was the alleged prior inventor, the prior user the sailboard maker] unquestionably a person skilled in the art of designing sailboards.

. . . . .

In summary, it is my view that the testimony of Cuthbertson [expert for the plaintiff] in effect was neutralized by that of Herreshoff [who was saying it was obvious]. It was not necessary to determine the testimony of which of those experts the trial judge preferred because the testimony of Darby ought to have been, if not conclusive, at least seriously considered as providing an important insight on the question of inventiveness. Since the use of the Marconi rig and of the wishbone boom and the concomitant advantages of using both sides of the sail were not obvious to this skilled witness until after the invention date, I find it difficult to say that the finding of obviousness of the learned trial judge can be supported by the evidence. I have concluded, therefore, that the invention in the patents in suit was not obvious.

Here, I will quote directly from the words of counsel for the plaintiff at p. 2098 of the transcript:

My lord, Dr. Beal is Newman Darby. He is the Newman Darby of the patent world. He had thought of the idea of using the one cable system, where the cable was attached to both a transmitter and a receiver. He knew about the Japanese articles. He wrote about it. He wrote an article. He was the classic skilled person possessed of the knowledge of the prior art. He was inventive; he had made inventions which were patented. He was respected by Dr. Harman as his mentor, at least initially, and it escaped Dr. Beal’s clever mind to go to an two-cable system to overcome the problem with the signal to noise ratio of the one cable system. If it wasn’t obvious to Dr. Beal, it could hardly be said that it would have been obvious to the unimaginative skilled workman, this unreal person.

My lord, I place the evidence of a real person who was possessed of better mental faculties than the unreal notional skilled workman to say conclusively that the invention was not obvious.

Counsel for the plaintiff also quotes Strayer J. in Mahurkar v. Vas-Cath of Canada Ltd., supra, who also found a "Newman Darby" in that case, and stated at p. 433:

…Dr. Uldall has no interest at stake [similar to Beal] and his evidence was to the same effect. He was indeed a most persuasive witness. He is generally credited with introducing the technique of using a catheter in the subclavian vein for purposes of dialysis. He invented a single lumen catheter for this purpose and then a co-axial double lumen catheter. Before his co-axial lumen catheter had really enjoyed wide-spread sales, however, the Mahurkar catheter as manufactured and sold by Quinton had come on the market. Dr. Uldall testified that he immediately recognized the Mahurkar catheter was superior to his own… If the invention was not obvious to Dr. Uldall, it would not have been obvious to a mere skilled but unimaginative technician.

The same thing is true of Beal. As indicated earlier, I find that the invention of the patent in suit was not obvious.


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