Fees that come due after grant
A granted US utility patent does not stay in force on its own. The USPTO charges maintenance fees at set points during the patent's life, each with a payment window followed by a grace period that carries a surcharge. If a fee is still unpaid when the grace period closes, the patent expires. Design patents and plant patents do not carry maintenance fees in the US, which surprises owners who manage mixed portfolios. Patents granted in other countries run on their own schedules, often with yearly annuities, and a missed payment in one country does not cure or affect the others.
When a payment has been missed
An expired patent is not always lost for good. The USPTO has a petition process for accepting a late maintenance fee when the delay was unintentional, and the statement made in that petition should be accurate, because an inaccurate one can later be used to challenge the patent. The law also gives some protection to people who began using the invention while the patent was lapsed, so a revived patent may not reach everything that happened in the gap. Owners who find a lapse should move promptly rather than wait for the next budget cycle. Bring the patent number, the notices you received, and an account of who was responsible for the docket and what went wrong.
Deciding what is worth keeping
Each fee point is also a decision point. A patent that no longer covers anything you sell, license, or expect to assert may not justify the cost, while one that reads on a competitor's product may be worth more now than when it issued. Entity status matters as well: small and micro entities pay reduced fees, but eligibility is judged when each payment is made, and a company that has since licensed or assigned rights to a larger business may no longer qualify. Ownership and correspondence records should match reality, because notices go to the address on file. When a fee is coming due, we look at your docket, the status of each patent, and which ones line up with your current products and plans.
