How does a divisional application differ from a continuation-in-part application?

A divisional application discloses and claims only subject matter disclosed in the parent application, while a continuation-in-part (CIP) application may include new matter. The MPEP states:

A continuation-in-part application should not be designated as a divisional application. The Court of Appeals for the Federal Circuit has concluded that the protection of the third sentence of 35 U.S.C. 121 does not extend to continuation-in-part applications, stating that ‘the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.’

This means that divisional applications have certain protections against double patenting rejections that CIPs do not have.

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Topics: MPEP 200 - Types and Status of Application; Benefit and Priority, Patent Law, Patent Procedure
Tags: continuation-in-part application, Divisional application, patent application types