Can a parent application be used as prior art against a CIP application?

Yes, a parent application can be used as prior art against claims in a Continuation-In-Part (CIP) application that are not fully supported by the parent application. This situation is addressed in MPEP 2133.01, which cites a relevant case:

“See, e.g., Santarus, Inc. v. Par Pharmaceutical, Inc., 694 F.3d 1344, 104 USPQ2d 1641 (Fed. Cir. 2012)(patent issuing from parent application was relied upon as prior art against the claims in CIPs that did not find support in the parent application).”

This means that if a claim in the CIP application includes new matter not disclosed in the parent application, the parent application (or a patent issued from it) can potentially be used as prior art against that claim. This underscores the importance of carefully considering the content and timing of CIP filings.

To learn more:

Topics: MPEP 2100 - Patentability, MPEP 2133.01 - Rejections Of Continuation - In - Part (Cip) Applications, Patent Law, Patent Procedure
Tags: Cip, continuation-in-part, parent application