Legal basis: People's Republic of China (PRC) Patent Law.
Article 50 Where the patentee voluntarily declares in writing to the patent administration department of the State Council that he is willing to license any unit or individual to exploit his patent, and specifies the payment method and standard of the license fee, the patent administration department of the State Council shall make an announcement and implement the public license. Where a patent for utility model or design applies for a public license statement, a patent evaluation report shall be provided. Where the patentee withdraws the declaration of opening license, it shall make a written statement and make an announcement by the patent administration department of the State Council. The withdrawal of the statement of open license through public announcement shall not affect the effectiveness of the previously granted open license.
Article 75 Any of the following circumstances shall not be regarded as infringement of the patent right:
(1) The patentee or a unit or individual licensed by the patentee uses, promises to sell, sells or imports its patented products or products directly obtained by patented methods;
(2) Having manufactured the same product, used the same method or made necessary preparations for its manufacture and use before the patent application date, and continuing to manufacture and use it only within the original scope;
(3) Foreign means of transport temporarily passing through China's territorial waters and airspace use the relevant patents in their devices and equipment for their own needs in accordance with the agreements signed between their countries and China or international treaties to which they are both parties, or on the principle of reciprocity;
(four) the use of relevant patents for scientific research and experiments;
(5) manufacturing, using or importing patented drugs or patented medical devices for the purpose of providing information required for administrative examination and approval, or manufacturing or importing patented drugs or patented medical devices exclusively for them.