The designated time limit refers to the time limit specified by the examiner in various notices issued in accordance with the Patent Law and its implementing regulations for the applicant (or patentee) and other parties to respond or perform certain actions. The designated period is generally two months. In the substantive examination procedure of an invention patent application, the applicant has a time limit of four months to respond to the first notice of examination action. The above specified period shall be calculated from the date on which the presumed party receives the notice.