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Printed Publication Means Findable

Written from MPEP 2128. Examination guidance, not law. Current as of 22 August 2026.

What it says

A document is a printed publication if an interested skilled person exercising reasonable diligence could locate it, and Wayback Machine captures are prima facie dated by their time stamp.

Printed publication is a term of art that has almost nothing to do with printing. The test is findability. Was the document disseminated or made available such that a person interested and ordinarily skilled in the art, exercising reasonable diligence, could locate it?

A thesis in a university library qualifies if sufficiently accessible. So does a document in an online database.

The manual records a forum posting that counted, and the two findings it rested on are the ones that reach an engineering audience: the post was directed to those having ordinary skill in the art, and it was publicly accessible because sufficiently disseminated. Those are properties a mailing list, an issue tracker or a public discussion could have.

There is a second point that makes internet prior art usable at all. Web pages carry no inherent date, which is the practical obstacle to relying on one. The manual states that publications obtained via the Wayback Machine are prima facie deemed publicly accessible at the date and time in the time stamp. A page taken down years ago can still be dated.

What This Does Not Decide

Whether your repository is a printed publication is not answered here, and silence is not permission. The manual does not resolve it, and an engineer reading a page that does not mention repositories will reasonably conclude they are safe. They may not be. The forum-post finding turned on dissemination and audience, and a public repository can have both.
  • It does not say whether your docs site, post, repository or archived page is a printed publication.
  • It does not say anything was publicly accessible on any particular date.
  • The forum-post record is one posting that qualified on two findings. It is not a rule that forum posts are prior art.
  • It is not law. The MPEP is examiner guidance.

Educational, not legal advice. Whether any of this reaches a particular disclosure is a determination for a registered patent practitioner working from the actual facts and dates.

Sources