Are applications with different effective filing dates treated differently 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.

Yes, applications with different effective filing dates require special consideration during interference searches. The MPEP 1302.08 states: “Examiners are reminded that some applications, such as continuation-in-part applications, may contain claims entitled to different effective filing dates (see MPEP §§ 2133.01 and 2152.01), and that each effective filing date should be considered when performing the interference search.” This ensures that the search accounts for potential interfering subject matter across different time periods relevant to the application’s claims.