(2) the right of first use of a patented invention.
(3) Patents exclusively used for scientific research and experiments are not regarded as infringement.
(4) On a foreign means of transport that transits temporarily, the use of relevant patents in the devices and equipment of the means of transport for one's own needs shall not be regarded as patent infringement.
(5) Compulsory license. For a patent for invention or utility model, if the patentee fails to exploit or not fully exploit its invention within three years from the date of granting the patent right without justifiable reasons, the Patent Office may, upon the application of a unit with the conditions for exploitation, allow the unit to exploit its invention without the consent of the patentee, and the unit that has obtained the compulsory license shall still pay the patentee the royalties.
(6) An invention patent of great significance to the national economy or national defense construction may be requisitioned by the state, and the patentee shall be given reasonable compensation.
Legal basis: Article 50 of the Patent Law of People's Republic of China (PRC). 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 an open 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.