Maintenance fees coming due
3 maintenance fees come due in the 12 months from Nov 15, 2026, the next on Nov 30, 2026. Unpaid by Jun 1, 2027, that one lapses early.
A maintenance fee does not end a patent on its due date. It falls due at 3.5, 7.5
and 11.5 years from grant, and the patent lapses only if the fee is still unpaid at the end of the
six month grace period that follows.
| Patent | Title | Holder | Status | Fee due | Lapses if unpaid | Expires | Confidence |
|---|---|---|---|---|---|---|---|
| US 11,662,120 | Reduced Size Fire Tube Boiler System and Method of Operating Same In force Fee due Nov 30, 2026 Lapses if unpaid Jun 1, 2027 · High confidence | The Cleaver-Brooks Company, Inc. | In force | Nov 30, 2026 | Jun 1, 2027 | High confidence | |
| US 11,859,811 | Auxiliary Boiler Systems and Methods of Operating and Implementing Same In force Fee due Jul 2, 2027 Lapses if unpaid Jan 3, 2028 · High confidence | The Cleaver-Brooks Company, Inc. | In force | Jul 2, 2027 | Jan 3, 2028 | High confidence | |
| US 11,933,491 | Burner with Adjustable End Cap and Method of Operating Same In force Fee due Sep 19, 2027 Lapses if unpaid Mar 20, 2028 · High confidence | The Cleaver-Brooks Company, Inc. | In force | Sep 19, 2027 | Mar 20, 2028 | High confidence |
3 of 3 patents shown. Soonest fee due date first, then patent number.
Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.