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Methods for Treating "Plunge Zone" Issues When Extinguishing Full Surface Liquid Tank Fires

US 8,424,612 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Apr 23, 2025 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed Aug 4, 2005 as application 11/196,882 · Granted Apr 23, 2013
Base term, 20 years from filing, plus 931 days of patent term adjustment (USPTO delay)
Today
Lapsed Apr 23, 2025
2005 2028
Clock starts
Aug 4, 2005
No longer in force
Apr 23, 2025
Granted
Apr 23, 2013
Term would have run to
Feb 21, 2028
base term patent term adjustment after the term ends fee events Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
931
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
2 of 3
Maintenance fees paid
Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from grant. This counts the ones the record shows paid.
4
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Feb 21, 2028: its 20-year base term plus 931 days of term adjustment for prosecution delay. Confidence: High. from the record

How we calculated this date

One row per rule, each showing its own input and what it did to the date. A step we could not verify says so instead of resolving itself.
StepInputDate after this stepConfidence
Base term, 20 years from filingClock starts Aug 4, 2005, when this application, 11/196,882, was filedAug 4, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+931 days, USPTO patent term adjustment recordFeb 21, 2028High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Apr 23, 2025High confidence
Computed term endThe steps above, in orderApr 23, 2025High confidence

This family

US 8,424,612this patent
Apr 2025
Apr 2025
US 8,881,839Grace period ended
no later than Aug 2028
no later than Aug 2028
US 8,689,896Term ended
Aug 2025
Aug 2025
3 of 4 applications in this family shown, earliest filings first. The applications whose file history this site holds. The family may have others.

Assignments

Assignment documents as recorded at the USPTO, oldest first, with the reel and frame each was recorded at. A recorded assignment is a filed document, not a statement of current ownership, and the absence of a later one is not evidence that the last one still stands.
RecordedAssignorAssigneeConveyance
Nov 21, 2005
Reel 17254, frame 386
Williams, Dwight P.Williams Fire and Hazard Control, Inc.Assignment of Assignor's Interest
Nov 3, 2011
Reel 27171, frame 472
Williams Fire and Hazard Control, Inc.Willfire HC, LLCAssignment of Assignor's Interest
Oct 15, 2013
Reel 31407, frame 651
Willfire HC, LLCTyco Fire & Security GmbHAssignment of Assignor's Interest
Sep 27, 2018
Reel 47158, frame 767
Tyco Fire & Security GmbHTyco Fire Products LPAssignment of Assignor's Interest

Sources

Google Patents · The patent document at USPTO · Assignment records at USPTO

USPTO account required: This application in Patent Center · USPTO's maintenance fee lookup

Maintenance fee events come from USPTO's own fee records. Its fee lookup asks for the patent number and the application number.

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