What is the effect of a foreign patent’s term on its use as prior art under pre-AIA 35 U.S.C. 102(d)?

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 term or expiration of a foreign patent can impact its use as prior art under pre-AIA 35 U.S.C. 102(d). According to MPEP 2126:

“In re Monks, 588 F.2d 308, 200 USPQ 129 (CCPA 1978) interpreted the language ‘patented in a foreign country’ in pre-AIA 35 U.S.C. 102(d) to mean a patent which is enforceable.”

This interpretation means that a foreign patent must be enforceable to be considered as prior art under pre-AIA 35 U.S.C. 102(d). If a foreign patent has expired or is no longer in force, it may not qualify as prior art under this specific provision. However, it’s important to note that the patent might still be usable as prior art under other subsections of 35 U.S.C. 102, depending on its publication date and content.