The annual patent fee in Japan needs to be paid every year after the patent is granted. Generally, an annual fee of 1~3 years from the date of authorization is required when paying the authorization fee. Therefore, the annual fee of Japanese patent is paid from the fourth year from the date of patent application authorization, and the specific period is before the anniversary of patent authorization. If the annual fee is overdue, it can be paid within a grace period of 6 months after the normal payment period, but a certain late fee is required; The amount of overdue fine is twice the annual fee payable in the current year.
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