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

Examples of prior art in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Patents filed earlier in the 'gold rush' are often granted with broader coverage on average than applications filed later due to the rapid growth in prior art patent filings. — Peter Su, Forbes.com, 21 July 2026 No prior art experience necessary. — Sarah Z. Sleeper, San Diego Union-Tribune, 14 Mar. 2026 According to guidelines from the European Patent Office, clinical trial results can be critical to prior art, particularly when revealing unexpected or previously undisclosed therapeutic benefits. — Lucy Xiaolu Wang, The Conversation, 23 Sep. 2025 And in the university rankings, Harvard has seized the top spot from traditional tech powerhouses like MIT and Stanford, driven by patents that are more often cited as prior art in other recent patents. — Harry Goldstein, IEEE Spectrum, 1 June 2025 See All Example Sentences for prior art

Word History

First Known Use

1883, in the meaning defined above

Time Traveler
The first known use of prior art was in 1883

Rhymes for prior art

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Browse Nearby Words

prioral
prior art
priorate
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Cite this Entry

“Prior art.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prior%20art. Accessed 2 Aug. 2026.

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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
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