How does a continuation-in-part application affect the priority date?

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.

A continuation-in-part (CIP) application can have different priority dates for different parts of the disclosure. According to MPEP 201.08:

‘The continuation-in-part application may be entitled to the benefit of the filing date of the prior application as to the common subject matter disclosed in compliance with 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph.’

This means:

• Content shared with the parent application retains the earlier priority date.
• New matter added in the CIP has the filing date of the CIP as its priority date.
• Different claims in the CIP may have different priority dates based on their disclosure in the parent or CIP application.

Understanding these priority date implications is crucial for determining patentability and prior art considerations.

For more information on new matter, visit: new matter.