Thanks. So a patent could conceivably be obtained for the broader concept, but the claims would have to be drafted in such a way that they exclude the existing patent, correct? Then anyone producing a chair with 4 legs would have to obtain a license from (only) the first patent holder, and anyone producing a chair with any other number of legs would have to obtain a license from (only) the holder of the new patent.
From my limited understanding it's correct. If any of the existing patents/products infringe on (is covered by)
your claim, that claim is invalid.
In a case like this, would the existing patent work against the person trying to obtain the broader patent because of obviousness issues, or could the fact that the original patent didn't make a broader claim be used as evidence that the broader concept wasn't obvious? I know it would depend on the specific details of the case, but do you have any thoughts about the likely outcome in an abstract/generic sense?
Again, in my limited understanding, for getting a patent it's sort of irrelevant what the previous patent claims
. It's important
what it teaches
(describes in the specifications). Of course there such things as self enabling claims, but I would say that
those are both the claim and the spec at the same time. And it's not just patents that count, industry publications and known products
count too. I do not think you have to prove that the broad concept IS NOT obvious (although many examiners
would like to make you, judging by the info on these forums
). It's the examiner's job to prove that either
a) the broad concept you are describing IS obvious or b) each the inventions that are enabled by this concept and that
you are trying to claim would have been obvious to arrive to without the benefit of knowing your broad concept.
It's possible that after your patent is granted that your claims and the other patent claims overlap for some products. In that case
somebody making the product would have to either get licenses from both patent holders, or one of the patent holders would have
to invalidate the other's claim in court.