What is considered ‘diligent effort’ when trying to contact an inventor for joint invention?

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.

What is considered ‘diligent effort’ when trying to contact an inventor for joint invention?

When attempting to contact a joint inventor for patent application purposes, ‘diligent effort’ typically involves:

• Multiple attempts to reach the inventor through various communication methods (e.g., phone, email, postal mail)
• Reasonable time intervals between attempts
• Documenting all contact attempts and responses (or lack thereof)
• Exploring alternative contact methods if initial attempts fail

The MPEP 409.03(d) states: ‘Where inability to find or reach a nonsigning inventor ‘after diligent effort’ is the reason for filing under pre-AIA 37 CFR 1.47(b), a statement of facts should be submitted that fully describes the exact facts which are relied on to establish that a diligent effort was made.’ This emphasizes the importance of thoroughly documenting all efforts made to contact the inventor.