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US

Hybrid Cycle Rotary Engine

US 7,909,013 In force
OverviewFamilyAssignmentsSources & methods

Term ends Oct 23, 2028 · High confidence

Filed Aug 1, 2007 as application 11/832,483 · Granted Mar 22, 2011
Base term plus 449 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2007 2028
Clock starts
Aug 1, 2007
Term ends
Oct 23, 2028
Granted
Mar 22, 2011
base term patent term adjustment 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
449
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
3 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.
46
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term runs 449 days past its 20-year base term on prosecution delay. All three maintenance fees are recorded paid; no more fees are due. 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 1, 2007, when this application, 11/832,483, was filedAug 1, 2027High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+449 days, USPTO patent term adjustment recordOct 23, 2028High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderOct 23, 2028High confidence

This family

US 7,191,738Term ended
Jul 2023
Jul 2023
Application PCT/US2005/000932PCT application
no patent term
no patent term
US 7,909,013this patent
Oct 2028
Oct 2028
US 8,365,698In force
Jul 2029
Jul 2029
Application 61/085,928Provisional application
no patent term
no patent term
Application 61/149,889Provisional application
no patent term
no patent term
Application 61/154,539Provisional application
no patent term
no patent term
Application 61/184,627Provisional application
no patent term
no patent term
8 of 46 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
Sep 4, 2007
Reel 19777, frame 672
Shkolnik, Alexander C.; Shkolnik, NikolayLiquidpiston, Inc.Assignment of Assignor's Interest
Jun 10, 2009
Reel 22805, frame 396
Liquidpiston, Inc.Adams Capital Management IV, L.P.Security Agreement
Jan 21, 2011
Reel 25676, frame 991
Adams Capital Management IV, L.P.Liquidpiston, Inc.Release of Security Interest
Dec 16, 2015
Reel 37307, frame 760
Liquidpiston, Inc.Adams Capital Management IV, L.P.; Northwater Intellectual Property Fund L.P. 2Security Interest
Dec 16, 2015
reel/frame not recorded
Liquidpiston, Inc.Adams Capital Management IV, L.P.Security Interest
Dec 16, 2015
reel/frame not recorded
Liquidpiston, Inc.Northwater Intellectual Property Fund L.P. 2Security Interest
Nov 23, 2016
Reel 40410, frame 559
Adams Capital Management IV, L.P.; Northwater Intellectual Property Fund L.P.2Liquidpiston, Inc.Release of Security 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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