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Intercell Interference Mitigation

US 9,509,459 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Nov 29, 2020 on the fee record · High confidence

First maintenance fee unpaid; grace period ended.

Held by Wi-Lan Inc.
Filed Dec 6, 2013 as application 14/099,255 · Granted Nov 29, 2016
Base term, 20 years from filing, plus 180 days of patent term adjustment (USPTO delay)
Today
Lapsed Nov 29, 2020
2008 2029
Clock starts
Dec 3, 2008
No longer in force
Nov 29, 2020
Granted
Nov 29, 2016
Term would have run to
Jun 1, 2029
base term patent term adjustment after the term ends 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
180
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
0 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.
7
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 Jun 1, 2029: its 20-year base term plus 180 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 Dec 3, 2008, when application 12/327,732, the earliest non-provisional in its chain, was filed (this one was filed Dec 6, 2013)Dec 3, 2028High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+180 days, USPTO patent term adjustment recordJun 1, 2029High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events0 of 3 maintenance fees paidlapsed Nov 29, 2020High confidence
Computed term endThe steps above, in orderNov 29, 2020High confidence

This family

US 8,204,442In force
Jan 2031
Jan 2031
US 8,626,072In force
Dec 2028
Dec 2028
US 9,509,459this patent
Nov 2020
Nov 2020
US 10,348,463In force
Dec 2028
Dec 2028
US 10,985,881In force
Dec 2028
Dec 2028
US 11,824,800In force
Dec 2028
Dec 2028
US 12,785,873In force
Dec 2028
Dec 2028
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
Jun 20, 2017
Reel 42914, frame 596
Wi-Lan Inc.; Quarterhill Inc.Quarterhill Inc.Merger and Change of Name
Jul 12, 2017
Reel 43168, frame 323
Quarterhill Inc.Wi-Lan Inc.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.

The Patent Finder CompaniesExpirationsCalculatorWatchlistPricing MethodologyCorrectionsLegalPrivacysupport@thepatentfinder.com Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) Part of 137 Finder · © 2026 137 Finder LLC · Sources cited