What are the potential risks or drawbacks of filing a continuation-in-part application?

Filing a continuation-in-part (CIP) application can present several risks and potential drawbacks:

1. Different Effective Filing Dates: New matter in the CIP only gets the benefit of the CIP filing date, potentially exposing those claims to more prior art.

2. Reduced Patent Term: The patent term is measured from the filing date of the earliest application to which the CIP claims priority, potentially reducing the overall protection period for new matter.

3. Double Patenting Issues: Claims in the CIP may be subject to obviousness-type double patenting rejections based on the claims of the parent application.

4. Complexity in Litigation: The varying effective filing dates can complicate patent litigation, particularly when determining relevant prior art.

5. Difficulty in Claiming Priority: International applications may have difficulty claiming priority to a CIP due to the new matter.

While not explicitly stated in the provided MPEP section, these are important considerations derived from patent law and practice. The MPEP does note: “The mere filing of a continuation-in-part application does not itself create a presumption that the applicant acquiesces in any rejections which may be outstanding in the copending national nonprovisional application or applications upon which the continuation-in-part application relies for benefit.”

Applicants should carefully consider these factors when deciding whether to file a CIP or a new application.