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System and method for fault isolation in a packet switching network

US 8,867,335 In force
OverviewAssignmentsSources & methods

Also listed on Paradyne Corporation, an earlier holder on the record. The recorded assignments below show how it moved.

Collateral for a security interest recorded Feb 10, 2022 (JPMorgan Chase Bank, N.A., as Administrative Assistant).

Term ends Mar 17, 2032 · High confidence

Held by DZS Inc.
Filed May 12, 2003 as application 10/435,873 · Granted Oct 21, 2014
Base term plus 3232 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2003 2032
Clock starts
May 12, 2003
Term ends
Mar 17, 2032
Granted
Oct 21, 2014
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
3,232
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.

This patent's term runs 3232 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 May 12, 2003, when this application, 10/435,873, was filedMay 12, 2023High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+3232 days, USPTO patent term adjustment recordMar 17, 2032High 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 17, 2032High confidence

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 12, 2003
Reel 14064, frame 767
McLendon, Jonathon C.Paradyne CorporationAssignment of Assignor's Interest
Apr 26, 2012
Reel 28115, frame 393
Paradyne CorporationWells Fargo Bank, National AssociationPatent and Trademark Security Agreement
Aug 10, 2018
Reel 46619, frame 225
Paradyne CorporationWells Fargo Bank, National AssociationSecurity Interest
Feb 28, 2019
Reel 48467, frame 326
Dasan Network Solutions, Inc.; Premisys Communications, Inc.; Paradyne Networks, Inc.; Dasan Network Solutions, Inc. (Korea); Dasan Zhone Solutions, Inc.; Keymile GmbH; Paradyne CorporationPnc Bank, National AssociationSecurity Interest
Feb 28, 2019
Reel 49983, frame 856
Wells Fargo Bank, National AssociationParadyne CorporationRelease of Security Interest
Jun 4, 2020
Reel 52842, frame 504
Pnc Bank, National AssociationDasan Zhone Solutions, Inc.; Premisys Communications, Inc.; Paradyne Networks, Inc.; Paradyne Corporation; Dasan Network Solutions, Inc.; Keymile GmbH; Dasan Network Solutions, Inc.Release of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationDasan Zhone Solutions, Inc.Release of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationPremisys Communications, Inc.Release of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationParadyne Networks, Inc.Release of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationParadyne CorporationRelease of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationDasan Network Solutions, Inc.Release of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationKeymile GmbHRelease of Security Interest
Jun 4, 2020
reel/frame not recorded
Pnc Bank, National AssociationDasan Network Solutions, Inc.Release of Security Interest
Jan 19, 2022
Reel 58692, frame 577
Paradyne CorporationDZS Inc.Assignment of Assignor's Interest
Feb 10, 2022
Reel 58984, frame 564
DZS Inc.JPMorgan Chase Bank, N.A., as Administrative AssistantSecurity 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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