Can be paid back.
If the patentee fails to pay the annual fee on time (excluding the annual fee for the year when the patent right is granted) or the amount paid is insufficient, he may make up the payment within six months from the expiration date of the annual fee. If the payment time exceeds the prescribed period but is less than one month, no late payment fee will be paid. If the back payment exceeds the prescribed time by one month or more, a late payment fee of the corresponding amount calculated according to the following calculation method shall be paid:
One month (excluding a whole month) and two months (inclusive) exceeding the prescribed period two full months), the payment amount is 5% of the full annual fee.
If the period exceeds the prescribed period by two to three months (including three full months), the payment amount will be 10% of the full annual fee.
If the period exceeds the prescribed period by three to four months (including four full months), the payment amount is 15% of the full annual fee.
If the period exceeds the prescribed period by four to five months (including five full months), the payment amount will be 20% of the full annual fee.
If the period exceeds the prescribed period by five to six months, the payment amount is 25% of the full annual fee.
If the annual fee or late payment penalty is insufficient within the six-month late payment period and needs to be paid again, the late payment fee shall be made up in accordance with the late payment penalty standard during the late payment penalty period when the annual fee or late payment penalty is paid again. All annual fees and late fees paid.