The patent administrative department can conduct substantive examination within a few years of invention patent application.

Within three years from the date of application for an invention patent, the patent administration department of the State Council may conduct a substantive examination of the application based on the request made by the applicant at any time; if the applicant fails to request a substantive examination beyond the time limit without justifiable reasons, the applicant shall The application is deemed to be withdrawn. When the patent administration department of the State Council deems it necessary, it may conduct a substantive examination of an invention patent application on its own.