The limitation of patent disputes is 2 years, counting from the date when the patentee or interested party knows or should know. The so-called "knowing" means that the patentee or interested party has found out exactly that their rights and interests have been infringed.
The so-called "should know" means that the patentee or interested party does not know that his rights and interests have been infringed, but it can be inferred from objective facts that he should know. Such as public sale and use of infringing products; Patent Gazette has published other people's patent application documents, etc.
In the patent disputes mediated by the patent administration department, in most cases, the date when a legal fact appears is taken as the starting date of the limitation of action. For example, from the date of the authorization announcement, because the legal facts published in the patent announcement can be used as a condition to infer that it should know. Therefore, the patentee or interested party should pay attention to the information in the patent announcement, exercise the right to claim in time, and avoid losses caused by the delay of prescription.
Article 68 of the Patent Law stipulates that the limitation of action for patent infringement is two years, counting from the date when the patentee or interested party knows or should know about the infringement.
If the patentee fails to pay the appropriate royalty before the patent right is granted after the publication of the application for a patent for invention, the limitation period for requesting the royalty is two years, counting from the date when the patentee knows or should know that others are using his invention. However, if the patentee knows or should know before the patent right is granted, it shall be counted from the date when the patent right is granted.