How does the USPTO treat foreign language publications as prior art?
This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.
The USPTO considers foreign language publications as potential prior art, provided they meet the criteria for public accessibility and publication date. According to MPEP 2128:
“Prior art publications in a language other than English are considered as prior art as of their publication date, even though an English translation may not be available until a later date.”
Key points regarding foreign language publications:
- They are effective as prior art as of their original publication date
- An English translation is not required for the publication to be considered prior art
- If relied upon in a rejection, a translation may be necessary to establish the publication’s teachings
- The content of the foreign language publication must be enabling to a person of ordinary skill in the art
Examiners may use machine translations or human translations to understand the content, but the original foreign language publication serves as the basis for the prior art date.