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Apparatus for Converting Direct Current to Alternating Current Using an Active Filter to Reduce Double-Frequency Ripple Power of Bus Waveform

US 8,279,642 In force
OverviewFamilyAssignmentsSources & methods

Also listed on Solarbridge Technologies, Inc., an earlier holder on the record. The recorded assignments below show how it moved.

Term ends Oct 20, 2030 · High confidence

Filed Sep 21, 2009 as application 12/563,499 · Granted Oct 2, 2012
Base term plus 394 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2009 2030
Clock starts
Sep 21, 2009
Term ends
Oct 20, 2030
Granted
Oct 2, 2012
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
394
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.
4
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 394 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 Sep 21, 2009, when this application, 12/563,499, was filedSep 21, 2029High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+394 days, USPTO patent term adjustment recordOct 20, 2030High 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 20, 2030High confidence

This family

US 8,279,642this patent
Oct 2030
Oct 2030
Application PCT/US2010/041149PCT application
no patent term
no patent term
US 9,093,919In force
Jan 2030
Jan 2030
US 9,722,504In force
Sep 2029
Sep 2029
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
Mar 26, 2010
Reel 24145, frame 42
Chapman, Patrick L., MR.; Kuhn, Brian T., MR.; Balog, Robert S., MR.; Kimball, Jonathan W., MR.; Krein, Philip T., MR.; Gray, Alexander, MR.Solarbridge Technologies, Inc.Assignment of Assignor's Interest
Sep 2, 2014
Reel 33677, frame 870
Solarbridge Technologies, Inc.Silicon Valley BankSecurity Interest
Dec 19, 2014
Reel 34681, frame 475
Silicon Valley BankSolarbridge Technologies, Inc.Release of Security Interest
Dec 19, 2014
Reel 34687, frame 232
Solarbridge Technologies, Inc.Sunpower CorporationAssignment of Assignor's Interest
Sep 10, 2018
Reel 46964, frame 203
Sunpower CorporationEnphase Energy, Inc.Assignment of Assignor's Interest
Mar 25, 2026
Reel 74174, frame 532
Enphase Energy, Inc.Powerbridge Networks, LLCAssignment of Assignor's Interest
Apr 21, 2026
Reel 74426, frame 830
Powerbridge Networks, LLCGridscale Solutions, LLCAssignment 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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