The Patent Finder
US

Multiple Channel Locating

US 8,836,921 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Sep 16, 2026 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed Aug 7, 2013 as application 13/961,397 · Granted Sep 16, 2014
Base term, 20 years from filing
Today
Lapsed Sep 16, 2026
2009 2029
Clock starts
Jul 8, 2009
No longer in force
Sep 16, 2026
Granted
Sep 16, 2014
Term would have run to
Jul 8, 2029
base term 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
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.
6
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 Jul 8, 2029: 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 Jul 8, 2009, when application 12/499,758, the earliest non-provisional in its chain, was filed (this one was filed Aug 7, 2013)Jul 8, 2029High 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 16, 2026High confidence
Computed term endThe steps above, in orderSep 16, 2026High confidence

This family

US 8,531,650In force
Jun 2032
Jun 2032
US 8,836,921this patent
Sep 2026
Sep 2026
US 9,696,137In force
May 2030
May 2030
US 10,317,193In force
no later than Aug 2029
no later than Aug 2029
US 11,680,790In force
Nov 2031
Nov 2031
US 12,435,968In force
Jan 2030
Jan 2030
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
Aug 7, 2013
Reel 30963, frame 603
Feldkhun, Daniel; Braker, Benjamin; Moore, Eric DanielChiaro Technologies LLCAssignment of Assignor's Interest
Dec 5, 2016
Reel 40521, frame 378
Chiaro Technologies LLCCognex CorporationAssignment 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