What is a Continuation-in-Part Patent Application?

A continuation-in-part (“CIP”) application is a special type of patent application.  Today I’ll discuss  what a CIP application is, and later this week I’ll go over reasons you might want to file a CIP or file an original utility patent application instead.  CIP application practice, however, is complicated and subject to many considerations about past disclosures and uses of the subject matter as well as future handling of the application.  This explanation is just a brief description of what a CIP generally is in comparison to other patent applications.

A CIP application is a continuing application in that it continues a chain of cases from a senior, or parent, patent application with child patent applications.  The child applications possess a link in subject matter with the parent application.  A CIP application can be useful when you’ve made improvements to an existing invention that are so closely related that it would be desirable to place the new material in an application together with the old material.

A continuation-in-part application carries old subject matter over from a parent patent application and then adds new subject matter that was not contained within the parent.  The claims of a CIP application can have different filing dates from that of the parent application.  If claims in the CIP application are supported by the disclosure made in the parent application, then they will be given the filing date of the parent application; if there are claims which are supported only by the new subject matter, they receive the CIP’s actual filing date.