Legal basis: Article 35 of the Patent Law of People's Republic of China (PRC). Within three years from the date of filing, the administrative department for patent in the State Council may, upon the request of the applicant at any time, make a substantive examination of the application. If the applicant fails to request substantive examination within the time limit without justifiable reasons, the application shall be deemed to have been withdrawn. The patent administrative department of the State Council may, when it deems it necessary, examine the application for a patent for invention on its own.