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Systems and Methods for Synchronizing Operations Among a Plurality of Independently Clocked Digital Data Processing Devices Without a Voltage Controlled Crystal Oscillator

US 8,020,023 In force
OverviewFamilyAssignmentsSources & methods

Term ends Mar 15, 2027 · High confidence

Held by Sonos, Inc.
Filed May 9, 2007 as application 11/801,468 · Granted Sep 13, 2011
Base term plus 1078 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2004 2027
Clock starts
Apr 1, 2004
Term ends
Mar 15, 2027
Granted
Sep 13, 2011
base term patent term adjustment 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
1,078
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.
110
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term runs 1078 days past its 20-year base term on prosecution delay. All three maintenance fees are recorded paid; no more fees are due. 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 Apr 1, 2004, when application 10/816,217, the earliest non-provisional in its chain, was filed (this one was filed May 9, 2007)Apr 1, 2024High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+1078 days, USPTO patent term adjustment recordMar 15, 2027High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderMar 15, 2027High confidence

This family

US 8,234,395Term ended
Mar 2026
Mar 2026
US 7,571,014In force
Mar 2027
Mar 2027
Application PCT/US2004/023102PCT application
no patent term
no patent term
Application 11/278,473Abandoned
not computed
not computed
US 8,020,023this patent
Mar 2027
Mar 2027
US 8,086,752Lapsed on the fee record
Dec 2023
Dec 2023
US 8,290,603Lapsed on the fee record
Oct 2024
Oct 2024
US 8,370,678Term ended
Apr 2024
Apr 2024
8 of 110 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
May 9, 2007
Reel 19342, frame 752
Millington, Nicholas A. J.; Ericson, MichaelSonos, Inc.Assignment of Assignor's Interest
Nov 15, 2015
Reel 37112, frame 14
Sonos, Inc.Jpmorgan Chase Bank, N.a.Patent Security Agreement
Apr 1, 2016
Reel 38329, frame 253
Sonos, Inc.Gordon Brothers Finance CompanySecurity Interest
Jul 25, 2018
Reel 46625, frame 882
Gordon Brothers Finance CompanySonos, Inc.Release of Security Interest
Oct 15, 2021
Reel 58123, frame 206
Sonos, Inc.Jpmorgan Chase Bank, N.a.Security Agreement
Oct 18, 2021
Reel 58213, frame 597
Jpmorgan Chase Bank, N.a.Sonos, Inc.Release of Security 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.

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