On what date are patents generally concentrated?

The two most important dates of a patent are the filing date (priority date should be considered in special circumstances) and the announcement date (also called authorization date and authorization announcement date). The relevant legal provisions are summarized as follows for reference: Article 42 of the Patent Law stipulates that the term of the invention patent right is 20 years, and the term of the utility model patent right and the design patent right is 10 year, all of which are counted from the date of filing. Article 39 of the Patent Law stipulates that if the application for a patent for invention is not found to be rejected after substantive examination, the administrative department for patent in the State Council shall make a decision to grant the patent right for invention, issue a patent certificate for invention, and register and announce it at the same time. The invention patent right shall take effect as of the date of announcement. Article 40 of the Patent Law stipulates that if the application for a patent for utility model or design is not rejected after preliminary examination, the administrative department for patent in the State Council shall make a decision to grant the patent right for utility model or design, issue the corresponding patent certificate, and register and announce it at the same time. The patent right for utility model and the patent right for design shall take effect as of the date of announcement.