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Wear Assembly

US 8,839,535 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Sep 23, 2026 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed Dec 5, 2012 as application 13/705,615 · Granted Sep 23, 2014
Base term, 20 years from filing
Today
Lapsed Sep 23, 2026
2007 2027
Clock starts
Mar 28, 2007
No longer in force
Sep 23, 2026
Granted
Sep 23, 2014
Term would have run to
Mar 28, 2027
base term after the term ends fee events Updated Nov 15, 2026 · includes USPTO assignment & status data published Nov 15, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
None
Term adjustment
No prosecution delay on this record.
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.
13
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 Mar 28, 2027: its 20-year base term, with no 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 28, 2007, when application 11/729,502, the earliest non-provisional in its chain, was filed (this one was filed Dec 5, 2012)Mar 28, 2027High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Sep 23, 2026High confidence
Computed term endThe steps above, in orderSep 23, 2026High confidence

This family

US 7,882,649In force
Sep 2028
Sep 2028
US 8,122,621In force
Mar 2027
Mar 2027
Application 13/369,699Abandoned
not computed
not computed
US 8,689,472Lapsed on the fee record
Apr 2026
Apr 2026
Application 13/705,562Abandoned
not computed
not computed
US 8,839,535this patent
Sep 2026
Sep 2026
US 9,493,930In force
Mar 2027
Mar 2027
US 9,816,254Lapsed on the fee record
Nov 2025
Nov 2025
8 of 13 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
Jan 31, 2013
Reel 29730, frame 860
Carpenter, Christopher M; Conklin, Donald M; Morris, Ray J; Bearden, James E; Durand, Severn DEsco CorporationAssignment of Assignor's Interest
May 9, 2013
Reel 30388, frame 273
Radzius, DziugasEsco CorporationAssignment of Assignor's Interest
Jul 6, 2016
Reel 39267, frame 771
Esco CorporationBank of America, N.A., as Administrative AgentNotice of Grant of Security Interest in Patents
Jul 16, 2018
Reel 46356, frame 64
Bank Of America, N.a.Esco CorporationRelease of Security Interest
Aug 17, 2018
Reel 46848, frame 493
Esco Corporation; Esco Group LLCEsco Group LLCMerger and Change of Name

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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