I don't think it's negligence that resulted in the sawmakers not using it -- but a recognition that the method was too expensive for the consumer value.
There I think you've got it wrong. This article has some real numbers on costs, and my very conservative estimates are that the costs to a consumer of the hazard of a saw are at least $50,000 (price of finger) * 1/50 (changes of a given saw cutting off a finger) = $1,000 while the costs of adding the technology are at most $150 (materials and manufacturing) + $150 (max licensing fee for an expensive machine) = $300. This, ahem, very strongly makes an economic case for the feature, and the fact that a no-name company has become successful selling table saws based on it provides an existence proof of its viability as well.
Whether it was poor judgement or an anti-safety conspiracy which led to the manufacturers not licensing the feature is something one could debate, but the applicability of liability here is very clear cut, unless one believes that noone should have product liability for anything ever.
I just find it troubling that a patented technology should ever be required purchasing. It seems to go against the whole exclusive rights part of the patent system.
We seem to disagree with where the logic has gone off the rails here. I believe the logic behind the liability in this case is rock solid - seriously, have you *seen* how effective the sawstop is? Do you know how common lost fingers are? My opinion is that the system goes off the rails at the point where it gives a flat monopoly protection with no exceptions where something is crucial to the public good. That is assuming, of course, that the monopoly should be granted at all in the first place. I agree with what other commenters have said about this being an unusually non-abusive patent, but even in this case I think things would be much the same even if there were no patents - sawstop would have still invented their safety device, and still have started selling high end saws based on it, they just would have gone straight to manufacturing their own and not wasted time trying to license the technology first.
As for Sawstop lauding this court decision, my guess is that whoever's behind it has an honest concern for keeping peoples's fingers from getting cut off. Sure it's probably good for their business (and would be without patents too) but there's no need to assume machiavellian motivation.
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