Ex Officio Examination in the Invalidation Procedure

Under the current Guidelines for Patent Examination, in the invalidation procedure, the Patent Reexamination Board follows two basic principles—the principle of examination upon request and the principle of conducting examinations ex officio—to determine the scope of examination of a case, i.e., to generally perform examination only on the causes and evidence of the request for invalidation submitted by the invalidation petitioner. But the causes and evidence not mentioned by the invalidation petitioner may be introduced ex officio in specific circumstances.