The patentee is obligated to pay for an annual fee beginning with the year in which the patent right is granted. He may choose to pay for the annual fee for one or several years at the same time. The patent law also allows the patentee having six-month to revive the patent by paying a penalty if he missed the initial deadline. But once the patentee fails to pay the annual fee and penalty within the prescribed time limit, the patent would be deemed to be abandoned.
 
Here is a list of the annual fees for utility model patent in China. The penalty is charged from the second months of the expiration date, in an amount of 5% of current year's annual fee, and increased at a rate of 5% of each month until the six months, i.e. 25% of the annual fee of the current year. For example, the penalty for the 4th years of an invention patent is from 60 CNY and up to 300 CNY.

 

How to restore the patent if you missed the deadline?
 
If the applicant still fails to pay or pay in the full amount of the annual fee and the penalty, a Notification of Termination of Patent Right will be issued approximately two months after the expiration of the penalty period. The applicant can file a petition to request for restoration of right within two months from the receipt date of the notification by paying 1000 CNY restoration fee. It is the last chance for the patentee to remedy, once the patentee still fails to request for restoration and pay all the fee, the patent would be invalid. The patent right shall be terminated from the date on which the time limit for payment of the annual fee expires.