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Silicon Carbide Devices Having Smooth Channels

US 8,188,483 Term ended
OverviewFamilyAssignmentsSources & methods

Term ended Aug 3, 2025 · High confidence

No current holder resolved from the recorded chain.
Filed Apr 16, 2009 as application 12/424,960 · Granted May 29, 2012
Base term plus 71 days of patent term adjustment (USPTO delay)
Today
20 years from filing
Term ended Aug 3, 2025
2005 2026
Clock starts
May 24, 2005
Term ended
Aug 3, 2025
Granted
May 29, 2012
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
71
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.
5
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 71 days past its 20-year base term on prosecution delay. All three maintenance fees were paid, so no fee lapse ended it. 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 May 24, 2005, when application 11/136,057, the earliest non-provisional in its chain, was filed (this one was filed Apr 16, 2009)May 24, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+71 days, USPTO patent term adjustment recordAug 3, 2025High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidterm endedHigh confidence
Computed term endThe steps above, in orderAug 3, 2025High confidence

This family

US 7,528,040In force
Nov 2026
Nov 2026
Application PCT/US2006/009493PCT application
no patent term
no patent term
US 8,188,483this patent
Aug 2025
Aug 2025
US 8,859,366Term ended
no later than Jul 2025
no later than Jul 2025
US 9,142,663Term ended
May 2025
May 2025
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
Apr 2, 2013
Reel 30129, frame 507
Cree Inc.; Cree, Inc.UsafConfirmatory License
Jun 30, 2023
Reel 64185, frame 755
Wolfspeed, Inc.U.S. Bank Trust Company, National AssociationSecurity Interest
Sep 30, 2025
Reel 72989, frame 1
U.S. Bank Trust Company, National Association, as Collateral AgentWolfspeed, Inc.Release of Security Interest in Intellectual Property Collateral at Reel/Frame No. 64185/0755

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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