# Maintenance fees

Periodic fees that must be paid to the USPTO to keep a granted utility patent in force. For US utility patents, fees are due at 3.5 years, 7.5 years, and 11.5 years after grant. If a fee is missed, the patent expires. Many patents go abandoned not because the invention was worthless, but because the owner decided the cost of maintenance wasn't justified by the remaining commercial value.

**Full entry:** https://patentbrief.org/glossary/maintenance-fees

**All patent terms:** https://patentbrief.org/glossary

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_Source: PatentBrief — https://patentbrief.org. A plain-English glossary of US patent terms._