Priority principle

if the same product has been manufactured before the filing date, the same method has been used, or the products have been manufactured, used and prepared, and they continue to be manufactured and used only within the original scope, it will not be regarded as infringement. This is the principle of preemption.

Legal basis:

Article 62 of the Patent Law of the People's Republic of China, where the same product has been manufactured before the filing date, the same method has been used, or the manufacturing, use and preparation have been made, and the manufacturing and use are continued only within the original scope, it shall not be regarded as infringement.