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US

Process for Manufacturing Zirconia-Treated Titanium Dioxide Pigments

US 7,238,231 In force
OverviewFamilyAssignmentsSources & methods
Collateral for a security interest recorded Oct 2, 2017 (Bank of America, N.A.).

Term ends Nov 16, 2026 · High confidence

Held by Tronox LLC
Filed Nov 16, 2006 as application 11/600,643 · Granted Jul 3, 2007
Base term, 20 years from filing
Today
20 years from filing
2006 2026
Clock starts
Nov 16, 2006
Term ends
Nov 16, 2026
Granted
Jul 3, 2007
base term 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
None
Term adjustment
No prosecution delay on this record.
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.
2
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 is its 20-year base term, with no adjustment for 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 Nov 16, 2006, when this application, 11/600,643, was filedNov 16, 2026High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh 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 orderNov 16, 2026High confidence

This family

US 7,238,231this patent
Nov 2026
Nov 2026
Application PCT/US2007/022059PCT 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
Nov 16, 2006
Reel 18612, frame 545
Craig, Daniel H.; Elliott, Jeffrey D.; Ray, Harmon E.Tronox LLCAssignment of Assignor's Interest
Aug 21, 2008
Reel 21411, frame 792
Tronox LLC F/K/A Kerr-McGee Chemical LLCLehman Commercial Paper Inc.Security Agreement
Feb 15, 2011
Reel 25795, frame 130
Tronox LLCGoldman Sachs Lending Partners LLC, as Collateral AgentSecurity Agreement
Feb 22, 2011
Reel 25822, frame 26
Tronox LLC; Tronox Pigments (Savannah) Inc.Wells Fargo Capital Finance, LLC, as AgentSecurity Agreement
Mar 24, 2011
Reel 26010, frame 684
Lehman Commercial Paper, Inc.Tronox LLCBankruptcy Court Notice Confirming Release of Liens Effective 2/14/2011
Feb 9, 2012
Reel 27682, frame 64
Goldman Sachs Lending Partners LLCTronox LLCRelease of Security Interest
Feb 9, 2012
Reel 27682, frame 86
Tronox LLCGoldman Sachs Bank USA, as Collateral AgentSecurity Agreement
Jul 12, 2012
Reel 28535, frame 362
Wells Fargo Capital Finance, LLCTronox LLC; Tronox Worldwide LLCRelease of Security Interest in Patents
Jul 12, 2012
reel/frame not recorded
Wells Fargo Capital Finance, LLCTronox LLCRelease of Security Interest in Patents
Jul 12, 2012
reel/frame not recorded
Wells Fargo Capital Finance, LLCTronox Worldwide LLCRelease of Security Interest in Patents
Jul 18, 2012
Reel 28582, frame 669
Tronox LLC; Tronox Worldwide LLCUBS AG, Stamford BranchPatent Security Agreement
Sep 25, 2017
Reel 43993, frame 306
UBS AG, Stamford Branch, as Collateral AgentTronox LLC; Tronox Worldwide LLCRelease of Security Interest in Patents
Sep 25, 2017
Reel 43993, frame 340
Tronox LLCWells Fargo Bank, National AssociationSecurity Interest
Sep 25, 2017
reel/frame not recorded
UBS AG, Stamford Branch, as Collateral AgentTronox LLCRelease of Security Interest in Patents
Sep 25, 2017
reel/frame not recorded
UBS AG, Stamford Branch, as Collateral AgentTronox Worldwide LLCRelease of Security Interest in Patents
Sep 26, 2017
Reel 44018, frame 893
Goldman Sachs Bank USA, as Collateral AgentTronox LLCRelease of Security Interest in Intellectual Property Collateral at Reel/Frame Nos. 027682/0086 and 030047/0422
Oct 2, 2017
Reel 44100, frame 339
Tronox LLCBank of America, N.A., as Collateral AgentPatent Security Agreement
May 1, 2020
Reel 52554, frame 529
Tronox LLCWilmington Trust, National Association, as Collateral AgentSecurity Interest
Mar 12, 2021
Reel 55578, frame 880
Bank Of America, N.a.HSBC Bank USA, National Association, as the Successor Administrative Agent and Collateral AgentAssignment of Security Interest in Patent Collateral Recorded at Reel/Frame 044100/0339
Mar 12, 2021
Reel 55583, frame 1
Wells Fargo Bank, National AssociationTronox LLCRelease of Security Interest
Apr 7, 2022
Reel 59629, frame 581
Wilmington Trust, National AssociationTronox LLCRelease of Security Interest
Sep 26, 2025
Reel 72942, frame 255
Tronox LLCWilmington Trust, National Association, as Collateral AgentSecurity 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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