Where a patent for invention is granted for four years from the date of application for a patent for invention and three years from the date of request for substantive examination, the patent administration department of the State Council shall, at the request of the patentee, compensate for the unreasonable delay of the invention patent in the process of authorization, except for the unreasonable delay caused by the applicant.
legal ground
In Article 42 of the Patent Law of People's Republic of China (PRC), the term of the invention patent right is 20 years, and the term of the utility model patent right and the design patent right is 10 years, all of which are counted from the date of application.