What are the circumstances of compulsory licensing of patent right?

1. A compulsory license that fails to obtain the right to use within a reasonable period of time shall meet the following conditions: First, the requester must meet the implementation conditions, that is, the basic conditions for producing, manufacturing and selling patented products or using patented methods; Second, the claimant must negotiate with the patentee on the implementation of his patent on reasonable terms, mainly on the payment of royalties, technical services and other basic obligations that both parties need to perform; Third, the claimant failed to obtain the permission of the patentee within a reasonable period of time. 2. In case of national emergency or extraordinary circumstances, or for the purpose of public interest, the administrative department for patent in the State Council may grant a compulsory license to exploit the patent for invention or utility model. 3. Compulsory license of subordinate patents The compulsory license of subordinate patents is granted based on the dependence between patents, that is, "a patented invention or utility model is a significant technological progress with significant economic significance compared with the invention or utility model for which the patent was applied earlier, and its implementation depends on the implementation of the prior invention or utility model". In order to promote the implementation of advanced patented technology, it is necessary to give the post-patentee a compulsory license to implement the pre-patented technology. At the same time, the former patentee should also be granted a compulsory license for the patented technology after implementation.