What is required to claim the benefit of an earlier filing date under 35 U.S.C. 120?

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.

To claim the benefit of an earlier filing date under 35 U.S.C. 120, the following requirements must be met:

• The later-filed application must be an application for a patent for an invention which is also disclosed in the prior application
• The disclosure of the invention in the prior application and in the later-filed application must be sufficient to comply with the requirements of 35 U.S.C. 112(a) except for the best mode requirement
• The later-filed application must contain a specific reference to the prior application
• The later-filed application must be filed before the patenting or abandonment of or termination of proceedings on the first application

As stated in the MPEP: “To be entitled to the benefit of the filing date of an earlier-filed application, the later-filed application must be an application for a patent for an invention which is also disclosed in the prior application (the parent or earlier-filed nonprovisional application or provisional application for which benefit is claimed); the disclosure of the invention in the prior application and in the later-filed application must be sufficient to comply with the requirements of 35 U.S.C. 112(a) except for the best mode requirement.”