What is the significance of application and patent dates in interference searches?

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.

Application and patent dates are not limiting factors in interference searches. According to MPEP 2304.01(a):

“The search should be directed to all subject matter encompassed by the claims, whether or not the claims are limited by an application or patent date.”

This means that:

• Examiners must search for potentially interfering subject matter regardless of filing dates
• Older applications or patents can still be relevant to an interference search
• The focus is on the subject matter of the claims, not the temporal aspects of the applications or patents

This approach ensures a comprehensive search that identifies all potential conflicts, regardless of when the applications were filed or patents were issued.