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What is prior art?

Prior art is the body of public knowledge that patent examiners (and you) can sift through to determine whether a patent application describes a new and nonobvious invention.

Prior art can take many forms, from patents granted in the 1800s, to diagrams published in foreign scientific journals. High quality prior art, described accurately and submitted to the USPTO is one of the most important things that determine whether a patent is granted.

But what is good prior art?

Good prior art is prior art that is significant to the patent’s claims. To demonstrate this, when you submit prior art to the USPTO, the examiners ask that you submit a short description (no more than a paragraph) that describes the significance of your submission. That should generally include:

  • What is it? (Link or attach)
  • When was it published?
  • What, specifically, did it do first?

Relevant prior art must prove that an infringing application or patent breaches one of 2 tenets of patent law: novelty and non-obviousness. It either proves a patent or application describes an old idea, or it that it is an obvious innovation on the old idea.

Novelty is fairly straightforward. Non-obviousness is not. What’s obvious to you is not obvious to someone else. A non-obvious patent is a patent that takes a substantial leap into the future from the “state of the art” that precedes it. Wikipedia — which is sometimes used by examiners to get an overview of a class of inventions — puts it well:

One of the main requirements of patentability is that the invention being patented is not obvious, meaning that a “person having ordinary skill in the art” would not know how to solve the problem at which the invention is directed by using exactly the same mechanism.

You may have to read that more than once. The gist: find prior art that shares a mechanism and solves the same problem as a patent, and you may have found a good reason that patent should not be granted.