Ex-parte re-examination (EPRx) has been available since 1981 (see MPEP 2200) and remains available under the America Invents Act (AIA).


Through Ex-parte re-examination, the patent owner or a third party may lodge a request for USPTO examination of an already-granted patent based on patents and printed publications that they bring to the USPTO’s attention. Such a request can be filed at any time during the enforceability of a patent, and the requester must establish that the submitted prior art establishes a substantial and new question of patentability (SNQ), at which point the USPTO will grant the reexamination request and order examination (i.e., reexamination) of the patent in question.