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Dual Fuel Vent Free Gas Heater

US 8,061,347 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Nov 22, 2023 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed Dec 21, 2009 as application 12/643,880 · Granted Nov 22, 2011
Base term, 20 years from filing, plus 122 days of patent term adjustment (USPTO delay)
Today
Lapsed Nov 22, 2023
2007 2027
Clock starts
Mar 9, 2007
No longer in force
Nov 22, 2023
Granted
Nov 22, 2011
Term would have run to
Jul 9, 2027
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
122
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.
5
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 Jul 9, 2027: its 20-year base term plus 122 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 Mar 9, 2007, when application 11/684,368, the earliest non-provisional in its chain, was filed (this one was filed Dec 21, 2009)Mar 9, 2027High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+122 days, USPTO patent term adjustment recordJul 9, 2027High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Nov 22, 2023High confidence
Computed term endThe steps above, in orderNov 22, 2023High confidence

This family

US 7,766,006In force
Apr 2027
Apr 2027
US 8,057,219Lapsed on the fee record
Nov 2023
Nov 2023
US 8,118,590Lapsed on the fee record
Feb 2024
Feb 2024
US 8,061,347this patent
Nov 2023
Nov 2023
Application 13/205,279Abandoned
not computed
not computed
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
Jan 6, 2012
Reel 27496, frame 641
Manning, SteveDesa IP, LLCAssignment of Assignor's Interest
Jan 6, 2012
Reel 27496, frame 650
Desa Heating, LLC; Desa LLC; Desa IP, LLC; DHP Holding II CorporationCoprecitec, S.l.Assignment of Assignor's Interest
Jan 6, 2012
Reel 27496, frame 647
Antxia Uribetxebarria, Jose Joaquin; Mateos Martin, RubenCoprecitec, S.l.Assignment 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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