: knowledge that is publicly available (as from the description in an already existing patent, from publications, or from public use or sale) before the date of filing a claim for a patent for an invention
a finding by the judge that there was no advancement of design in the new invention over the prior art
: the processes, devices, and modes of achieving the end of an alleged invention that were known or knowable by due diligence before and at the date of the invention;
also: the knowledge or description of such processes, devices, or modes —used chiefly in patent law
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