Reexamination Proceeding Law and Legal Definition

Any time during the enforceability of a patent any person can file a request for the United States Patent and Trademark Office (PTO) to conduct a second examination of any claim of the patent on the basis of prior art patents or printed publications, which the person states to be pertinent and applicable to the patent and believes to have a bearing on the patentability. For granting the request for reexamination, a substantial new question of patentability should be present with regard to at least one patent claim. The request has to be made in writing and should be accompanied by payment of a reexamination request filing fee as set forth in the statute.