Maintenance fee information includes details of last payment and next payment associated with the processing as follows:
No maintenance fee status is provided for patents granted prior to October 1, 1989.
For patent documents filed or granted from October 1, 1989, no maintenance fee status is provided if the patent document is no longer in force.
The last maintenance fee payment that was made. If some of the maintenance fees are prepaid, only the last of the prepaid payments is shown.
The date that the last maintenance fee payment was received in the Patent Office.
The amount actually paid for the last payment.
The next payment for either the small entity fee or the standard fee.
The date that the next maintenance fee payment is due in the Patent Office.
This is the prescribed amount due for the next maintenance fee payment (depending on whether or not the applicant/patentee is paying the standard fee or the small entity fee).