What is prior art?
Prior art is everything that was available to the public, anywhere in the world and in any form, before the date a patent application was filed: patents, articles, websites, products, videos, talks. A patent can only be granted for something that is not part of the prior art. A defensive publication is prior art created on purpose, to keep an invention free of patents.
The definition, in plain words
In European law, the "state of the art" is everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing (EPC Article 54). US law since 2013 works the same way, worldwide, with a 12-month exception for the inventor's own disclosures (35 U.S.C. 102).
Three things follow:
- Language and place don't matter. A publication in Croatian in Zagreb counts against a US application just like an English one.
- Form doesn't matter. A patent, a product sold in a shop, a YouTube video and a conference talk can all be prior art.
- The date matters. Only what was public before the filing date counts.
What is a defensive publication?
A defensive publication is a description of an invention published deliberately so that it becomes prior art, usually because the author doesn't want to patent it but doesn't want anyone else to either. Large technology companies have used defensive publications for decades. Open Prior Art makes them free and simple for anyone.
A defensive publication works if it is public, has a provable date, and describes the invention clearly enough for a skilled person to carry it out.
How patent examiners look for prior art
Examiners search mainly in patent databases, by keywords and by patent classes (CPC and IPC codes), and in technical literature. That is why Open Prior Art entries carry:
- an English title and summary, whatever the language of the original;
- CPC/IPC classes proposed by the author, chosen with help from the classes similar patents use;
- keywords and references to related patents and articles;
- a public page for each entry that search engines can index, and a copy in the Internet Archive.
Why the date has to be provable
If a publication is ever used against a patent, someone may question when it really became public. Open Prior Art records a fingerprint of each entry and has it timestamped by two independent timestamping services, and requests a copy from the Internet Archive. Anyone can check those records without relying on us. See how the proof works.
Questions
Is prior art only patents?
No. Anything made public before the filing date can be prior art: articles, websites, products, videos, talks, manuals, theses and defensive publications.
Does prior art have to be in English?
No. Prior art counts in any language. English titles and summaries just make it much easier for examiners to find.
What is the difference between a prior art search and creating prior art?
A prior art search looks for what was already public, for example before filing a patent or launching a product. Creating prior art means publishing something yourself, so that it becomes part of what is public.