Legal basis: People's Republic of China (PRC) Patent Law.
Article 42 The term of patent right for invention is 20 years, and the term of patent right for utility model and patent right for design is 10 years, counting from the date of application.
Article 48 Under any of the following circumstances, the administrative department for patent in the State Council may grant a compulsory license to exploit a patent for invention or utility model upon the application of a unit or individual with the conditions for implementation:
(1) It has been three years since the patent right was granted and four years since the patent application was filed, and the patentee has not implemented or not fully implemented his patent;
(2) The patentee's act of exercising the patent right is recognized as a monopolistic act according to law, so as to eliminate or reduce the adverse effects of the act on competition.