What is a CIP (continuation-in-part) patent application?
Under United States patent practice, it is possible for the owner of a pending patent application to file a what is called a “continuation-in-part” patent application. A CIP patent application is an application which contains some matter in common with a previous patent application (called the “parent” application), and that also contains new matter, and which was filed at a time when the parent application was pending. If such an application issues as a patent, then the patent has a sort of a blurred priority date. It is possible that some claims of the patent enjoy the priority date of the parent application, while other claims might enjoy only the filing date of the CIP application as their priority date.