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Wireless location determining device

US RE42,435 Lapsed on the fee record
OverviewSources & methods

Lapsed Dec 26, 2018 on the fee record · From the USPTO record

Third maintenance fee unpaid; grace period ended.

Named at grant Daak Wireless Fund L.L.C. · find this owner
Filed Dec 24, 2008 as application 12/343,706 · Granted Jun 7, 2011
Base term, 20 years from filing
Today
Lapsed Dec 26, 2018
2004 2026
Clock starts
Jul 6, 2004
No longer in force
Dec 26, 2018
Granted
Jun 7, 2011
Term would have run to
Jul 6, 2024
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 the original patent's grant, which is not on record here. This counts the ones the record shows paid.

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.
Step Input Date after this step Confidence
Base term, 20 years from filingClock starts Jul 6, 2004, when the earliest non-provisional application in its chain was filed (this one was filed Dec 24, 2008)Jul 6, 2024High confidence
Continuity chainA reissue: its term follows the original patent's, with the original's term adjustmentfollows the original patentMedium confidence
Patent term adjustmentNo term adjustment record on a grant after 2005, so none is addedno changeMedium confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Dec 26, 2018High confidence
Computed term endThe steps above, in orderDec 26, 2018From the USPTO record

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.

Not on this page: the patent's family, its recorded assignments and its citation count. USPTO's assignment records, linked above, list every recorded assignment.

Every date shows its work: the base term, any term adjustment or extension, any disclaimer cap, and the maintenance fee record, each with a confidence tier. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

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