legal ground
Article 17 of the patent law
If a foreigner, foreign enterprise or other foreign organization that has no habitual residence or business office in China applies for a patent in China, it shall be handled in accordance with the agreement signed between the country to which it belongs and China or the international treaties to which it is a party, or in accordance with the principle of reciprocity.
Article 18
Foreigners, foreign enterprises or other foreign organizations that have no habitual residence or business office in China shall entrust a legally established patent agency to apply for patents and handle other patent affairs in China.
Units or individuals applying for patents and handling other patent affairs in China may entrust a legally established patent agency to handle them.
Patent agencies shall abide by laws and administrative regulations, accept the entrustment of clients, and handle patent applications or other patent affairs; The contents of the client's invention and creation shall be kept confidential, except that the patent application has been published or announced. Specific measures for the administration of patent agencies shall be formulated by the State Council.