Are signatures on facsimile-transmitted documents acceptable in international patent applications?

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.

Yes, signatures on documents received via facsimile are generally acceptable in international patent applications, provided the facsimile transmission is permitted for that specific document type. The MPEP section 1834.01 states:

“A signature on a document received via facsimile in a permitted situation is acceptable as a proper signature.”

This acceptance is based on both international and U.S. regulations:

• PCT Rule 92.4(b)
• 37 CFR 1.4(d)(1)(ii)

It’s important to note that this applies only to documents that are permitted to be filed by facsimile. Certain documents, such as the initial international patent application, cannot be filed by fax and therefore would not fall under this provision for signature acceptance.