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Tilted Grating Sensor

US 8,554,024 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods
Collateral for a security interest recorded Dec 26, 2019 (Deutsche Bank Trust Company Americas).

Lapsed Oct 8, 2025 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed Feb 26, 2009 as application 12/439,031 · Granted Oct 8, 2013
Base term, 20 years from filing, plus 267 days of patent term adjustment (USPTO delay)
Today
Lapsed Oct 8, 2025
2006 2027
Clock starts
Oct 25, 2006
No longer in force
Oct 8, 2025
Granted
Oct 8, 2013
Term would have run to
Jul 19, 2027
base term patent term adjustment 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
267
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
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 grant. This counts the ones the record shows paid.
5
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Jul 19, 2027: its 20-year base term plus 267 days of term adjustment for prosecution delay. 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 Oct 25, 2006, when application PCT/CA2006/001749, the earliest non-provisional in its chain, was filed (this one was filed Feb 26, 2009)Oct 25, 2026High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+267 days, USPTO patent term adjustment recordJul 19, 2027High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Oct 8, 2025High confidence
Computed term endThe steps above, in orderOct 8, 2025High confidence

This family

US 8,554,024this patent
Oct 2025
Oct 2025
US 9,857,290Lapsed on the fee record
Jan 2022
Jan 2022
US 9,341,778In force
Nov 2033
Nov 2033
US 10,190,970Term ended
Oct 2026
Oct 2026
4 of 5 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
Feb 26, 2009
Reel 22316, frame 372
Albert, Jacques; Chen, Chengkun; Shevchenko, Yanina; Ivanov, AlexeiLxsix Photonics Inc.Assignment of Assignor's Interest
Feb 26, 2009
Reel 22316, frame 445
Lxsix Photonics Inc.Lxdata Inc.Change of Name
Jan 13, 2014
Reel 31997, frame 290
Lxdata Inc.Weatherford Canada PartnershipAmalgamation-Dissolution-General Conveyance and Assuption Agreement
Jul 27, 2017
Reel 43111, frame 828
Weatherford Canada PartnershipWeatherford Canada Ltd.Assignment of Assignor's Interest
Dec 18, 2019
Reel 51891, frame 89
Weatherford Technology Holdings LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity Inc.; Precision Energy Services Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Precision Energy Services ULC; Weatherford U.K. LimitedWells Fargo Bank National Association as AgentSecurity Interest
Dec 26, 2019
Reel 51419, frame 140
Weatherford Technology Holdings, LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity, Inc.; Precision Energy Services, Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Precision Energy Services ULC; Weatherford U.K. LimitedDeutsche Bank Trust Company Americas, as Administrative AgentSecurity Interest
Aug 28, 2020
Reel 54288, frame 302
Weatherford Technology Holdings, LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity, Inc.; Precision Energy Services, Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Precision Energy Services ULC; Weatherford U.K. LimitedWilmington Trust, National AssociationSecurity Interest
Aug 28, 2020
Reel 53838, frame 323
Wells Fargo Bank, National AssociationWeatherford Technology Holdings, LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity, Inc.; Precision Energy Services, Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Precision Energy Services ULC; Weatherford U.K. LimitedRelease of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford Technology Holdings, LLCRelease of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford Netherlands B.V.Release of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford Norge AsRelease of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationHigh Pressure Integrity, Inc.Release of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationPrecision Energy Services, Inc.Release of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford Canada Ltd.Release of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford Switzerland Trading and Development GmbHRelease of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationPrecision Energy Services ULCRelease of Security Interest
Aug 28, 2020
reel/frame not recorded
Wells Fargo Bank, National AssociationWeatherford U.K. LimitedRelease of Security Interest
Oct 1, 2021
Reel 57683, frame 423
Wilmington Trust, National AssociationWeatherford Technology Holdings, LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity, Inc.; Precision Energy Services, Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Precision Energy Services ULC; Weatherford U.K. LimitedRelease of Security Interest
Oct 1, 2021
Reel 57683, frame 706
Weatherford Technology Holdings, LLC; Weatherford Netherlands B.V.; Weatherford Norge As; High Pressure Integrity, Inc.; Precision Energy Services, Inc.; Weatherford Canada Ltd.; Weatherford Switzerland Trading and Development GmbH; Weatherford U.K. LimitedWilmington Trust, National AssociationSecurity Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford Technology Holdings, LLCRelease of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford Netherlands B.V.Release of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford Norge AsRelease of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationHigh Pressure Integrity, Inc.Release of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationPrecision Energy Services, Inc.Release of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford Canada Ltd.Release of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford Switzerland Trading and Development GmbHRelease of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationPrecision Energy Services ULCRelease of Security Interest
Oct 1, 2021
reel/frame not recorded
Wilmington Trust, National AssociationWeatherford U.K. LimitedRelease of Security Interest
Apr 26, 2023
Reel 63470, frame 629
Deutsche Bank Trust Company AmericasWells Fargo Bank, National AssociationPatent Security Interest Assignment Agreement

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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