Can an applicant retroactively obtain 35 U.S.C. 121 safe harbor protection?

No, an applicant cannot retroactively obtain the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting. The MPEP clearly states:

“A patentee cannot retroactively recover the safe harbor protection of 35 U.S.C. 121 against nonstatutory double patenting by amending a patent that issued from a continuation-in-part application to only subject matter in the parent application and redesignating the CIP as a divisional of the parent application.“

This principle has been affirmed in court decisions, including In re Janssen Biotech, Inc. and G.D. Searle LLC v. Lupin Pharm., Inc. The courts have emphasized that simply deleting new matter from a reissue patent or amending claims in a reexamination proceeding does not retroactively alter the nature of the application or bring it within the scope of the safe harbor provision.

To learn more:

• 35 U.S.C. 121
• safe harbor
• retroactive protection
• continuation-in-part
• divisional application