prior art

noun

patent law

: 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

Word History

First Known Use

1883, in the meaning defined above

Legal Definition

prior art

noun

: 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