What happens if a duplicate maintenance fee payment is submitted for a patent?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

When a duplicate maintenance fee payment is submitted for a patent, the USPTO’s handling depends on whether the payment complies with 37 CFR 1.366(c). The MPEP states:

“If the duplicate payment does not comply with 37 CFR 1.366(c) by not containing both the patent number and the corroborating application number, the Office will return the duplicate payment to the second fee submitter with an indication that the maintenance fee for the patent was already paid.“

If the payment does comply, the Office will verify the first payment’s processing and either return the duplicate payment or attempt to apply it, depending on the circumstances.