When can a patent owner file a request for supplemental examination?

A patent owner can file a request for supplemental examination at any time during the period of enforceability of the patent. This is specified in 37 CFR 1.601(c), which states:

“A request for supplemental examination of a patent may be filed at any time during the period of enforceability of the patent.”

This rule was established because the USPTO believes that Congress did not intend for resources to be spent on supplemental examination of patents that can no longer be enforced.

Patent Owner Can Request Supplemental Examination Any Time During Patent Enforceability MPEP 2808 Permitted
Period for Requesting Supplemental Examination Determined by Rule MPEP 2808 Prohibited
Supplemental Examination After Statute of Limitations MPEP 2808 Permitted
Patent Owner Determines Expiration Date for Supplemental Examination MPEP 2808 Informative
Enforceability Period Extended for Pending Litigation MPEP 2808 Permitted