What are the due years for maintenance fees for utility patents?

For utility patents, the due years for maintenance fees are set specifically to encourage the continued use and commercialization of the invention. The correct timeline for these maintenance fees is 3.5 years, 7.5 years, and 11.5 years after the grant of the patent.

At 3.5 years, the first maintenance fee is due. This is critical as it ensures the patent holder is still interested in maintaining their patent rights and is utilizing their invention. The subsequent maintenance fee is due at 7.5 years, after which the patent must again be maintained, indicating ongoing engagement with the patent. Finally, the last fee is due at 11.5 years, marking the end of a typical 20-year patent term from the grant date, accounting for any periods of earlier maintenance.

The other options do not align with the established timeline for maintenance fees set forth by the USPTO. The correct understanding of these due years is vital for any patent holder to avoid unintentional abandonment of their patent rights due to missed payments.