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System and Method for Damping Vibration in a Drill String Using a Magnetorheological Damper

US 8,087,476 In force
OverviewFamilyAssignmentsSources & methods

Term ends Dec 31, 2029 · High confidence

Held by APS Tech LLC
Filed Mar 5, 2009 as application 12/398,983 · Granted Jan 3, 2012
Base term plus 301 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2009 2029
Clock starts
Mar 5, 2009
Term ends
Dec 31, 2029
Granted
Jan 3, 2012
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
301
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.
4
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 301 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 Mar 5, 2009, when this application, 12/398,983, was filedMar 5, 2029High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+301 days, USPTO patent term adjustment recordDec 31, 2029High 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 orderDec 31, 2029High confidence

This family

US 8,087,476this patent
Dec 2029
Dec 2029
Application PCT/US2010/025897PCT application
no patent term
no patent term
US 9,976,360In force
Nov 2030
Nov 2030
Application PCT/US2012/054207PCT application
no patent term
no patent term
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 3, 2009
Reel 23045, frame 219
Wassell, Mark Ellsworth; Burgess, Daniel E.; Barbely, Jason R.APS Technology, Inc.Assignment of Assignor's Interest
Mar 14, 2012
Reel 27859, frame 181
APS Technology, Inc.Td Bank, N.a.Security Agreement
Apr 20, 2012
Reel 28080, frame 80
APS Technology, Inc.Enhanced Capital Connecticut Fund I, LLC; Enhanced Capital Connecticut Fund II, LLC; Enhanced Capital Connecticut Fund III, LLCSecurity Agreement
Apr 20, 2012
reel/frame not recorded
APS Technology, Inc.Enhanced Capital Connecticut Fund I, LLCSecurity Agreement
Apr 20, 2012
reel/frame not recorded
APS Technology, Inc.Enhanced Capital Connecticut Fund II, LLCSecurity Agreement
Apr 20, 2012
reel/frame not recorded
APS Technology, Inc.Enhanced Capital Connecticut Fund III, LLCSecurity Agreement
Mar 14, 2016
Reel 38077, frame 218
APS Technology, Inc.Enhanced Capital Connecticut Fund I, LLC, Enhanced Capital Connecticut Fund II, LLC, Enhanced Capital Connecticut Fund III, LLCRelease of Security Interest
Mar 24, 2016
Reel 38088, frame 615
TD Banknorth NATD Banknorth NARelease of Security Interest
Oct 10, 2017
Reel 44169, frame 53
APS Technology, Inc.; APS Industries, Inc.; Apst International, Inc.Balance Point Capital Partners III, LPSecurity Interest
Dec 21, 2017
Reel 44935, frame 125
TD Banknorth NAAPS TechnologyCorrective Assignment to Correct the Receiving Party Name Previously Recorded on Reel 038088 Frame 0615. Assignor(S) Hereby Confirms the Trademark Security Agreement.
Dec 21, 2017
Reel 44935, frame 603
Enhanced Capital Connecticut Fund I, LLC, Enhanced Capital Connecticut Fund II, Enhanced Capital Connecticut Fund III, LLCAPS TechnologyCorrective Assignment to Correct the Conveying Party Name Previously Recorded on Reel 038077 Frame 0218. Assignor(S) Hereby Confirms the Terminates Security Agreement.
Feb 7, 2019
Reel 48375, frame 848
APS Technology, Inc.; APS Industries, Inc.; Apst International, Inc.Keybank National AssociationSecurity Interest
Feb 7, 2019
Reel 49856, frame 434
APS Technology, Inc.; APS Industries, Inc.; Apst International, Inc.Balance Point Capital Partners III, LPAmended and Restated Intellectual Property Security Agreement
Jan 17, 2024
Reel 66341, frame 846
APS Technology LLCBalance Point Capital Partners III, LP, as AgentSecurity Interest
Feb 1, 2024
Reel 66405, frame 762
Keybank National AssociationAPS Technology Inc.; APS Industries Inc.; Apst International Inc.Release of Security Interest
Feb 1, 2024
reel/frame not recorded
Keybank National AssociationAPS Technology Inc.Release of Security Interest
Feb 1, 2024
reel/frame not recorded
Keybank National AssociationAPS Industries Inc.Release of Security Interest
Feb 1, 2024
reel/frame not recorded
Keybank National AssociationApst International Inc.Release of Security Interest
Oct 7, 2025
Reel 73016, frame 572
APS Technology LLCAPS Tech LLCAssignment 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.

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