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Single-chip audio circuits, methods, and systems using the same

US 6,952,621 Term ended
OverviewSources & methods

Term ended Aug 6, 2020 · From the USPTO record

Named at grant Crystal Semiconductor Corp. · find this owner
Filed Nov 20, 2000 as application 09/717,407 · Granted Oct 4, 2005
Base term plus 1027 days of patent term adjustment (USPTO delay)
Today
20 years from filing
Term ended Aug 6, 2020
1997 2026
Clock starts
Oct 14, 1997
Term ended
Aug 6, 2020
Granted
Oct 4, 2005
base term patent term adjustment 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
1,027
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.

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 Oct 14, 1997, when the earliest non-provisional application in its chain was filed (this one was filed Nov 20, 2000)Oct 14, 2017High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+1027 days, USPTO patent term adjustment recordAug 6, 2020High 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 6, 2020From 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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