What will happen when a prior art is found after the patent is granted?

A patent P was granted by USPTO and after the patent is published, a prior art PA of the P is found. Now what will happen to the patent P?

If publishers of PA sue to publishers of P for any product (made on P, as well as on PA), will USPTO take any portion of responsibility for justification?

Note: PA was itself published by USPTO as a patent but somehow everyone missed it in prior art search for P.

  • Of course they have a patent PA already published Oct 10, 2021 at 5:15
  • 1
    It was not clear that PA was a patent related document let alone an issued patent. “Published” is not synonymous with “issued a patent”. A magazine article is published and a patent application is published, a patent is granted or issued.
    – George White
    Oct 10, 2021 at 5:33
  • @GeorgeWhite sorry for the misunderstanding. I have updated the question. Oct 10, 2021 at 7:13
  • As George White explained, prior art in no way implies a previous patent. For the most part the USPTO is very good at finding prior art in patents. Prior art that is published on the internet, for instance, is more likely to go unnoticed.
    – Eric S
    Oct 10, 2021 at 16:03
  • I'd also like to point out that published and granted are two different things with respect to patents.
    – Eric S
    Oct 10, 2021 at 16:05

1 Answer 1


No the USPTO will have no responsibility for missing a particular prior art document.

In a comment the OP clarified that PA resulted in a patent. That was not stated in the original question. In that case the two patents have overlapping claims and if anyone makes a product within that overlap subject matter either of the two parties could sue the producer for infringement. The P patent is unlikely to survive such a law suit if the defendant finds PA.

Separately, anyone ( including the owners of PA) can file an IPR with the USPTO to attempt to invalidate P.


  • I have modified the question, sorry for the inconvenience. But why USPTO do not take any portion of liability as they are working as a trust centre for innovators? Oct 10, 2021 at 7:12
  • Perhaps a a link to background on an IPR would be helpful.
    – Eric S
    Oct 10, 2021 at 16:04

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .