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US

Turbidimeter Improvements

US 7,430,043 In force
OverviewFamilyAssignmentsSources & methods

Also listed on North American Filtration Holdings LLC, an earlier holder on the record. The recorded assignments below show how it moved.

Collateral for a security interest recorded May 7, 2026 (JPMorgan Chase Bank, N.A.).

Term ends Jun 7, 2027 · High confidence

Held by Chemtrac LLC
Filed Jun 7, 2007 as application 11/810,817 · Granted Sep 30, 2008
Base term, 20 years from filing
Today
20 years from filing
2007 2027
Clock starts
Jun 7, 2007
Term ends
Jun 7, 2027
Granted
Sep 30, 2008
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.
3
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 Jun 7, 2007, when this application, 11/810,817, was filedJun 7, 2027High 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 orderJun 7, 2027High confidence

This family

US 7,303,685Term ended
Aug 2026
Aug 2026
US 7,413,666In force
Mar 2027
Mar 2027
US 7,430,043this patent
Jun 2027
Jun 2027
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 2, 2010
Reel 25227, frame 406
Evans, James MChemtrac Systems, Inc.Assignment of Assignor's Interest
Apr 28, 2011
Reel 26191, frame 754
Chemtrac Systems, Inc.Chemtrac, Inc.Assignment of Assignor's Interest
Apr 6, 2022
Reel 59509, frame 921
North American Filtration Holdings LLC; Naf Water Filtration Enterprises LLC; Naf Water Solutions Enterprises LLC; Naf Aquatics Enterprises LLC; Naf Water Filtration LLC; Chemtrac LLC; Naf Aquatics LLCLive Oak Banking CompanySecurity Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNorth American Filtration Holdings LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNaf Water Filtration Enterprises LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNaf Aquatics Enterprises LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNaf Aquatics LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyChemtrac LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNaf Water Solutions Enterprises LLCRelease of Security Interest
Nov 3, 2025
reel/frame not recorded
Live Oak Banking CompanyNaf Water Filtration LLCRelease of Security Interest
Nov 3, 2025
Reel 72760, frame 571
Live Oak Banking CompanyNorth American Filtration Holdings LLC; Naf Water Filtration Enterprises LLC; Naf Aquatics Enterprises LLC; Naf Aquatics LLC; Chemtrac LLC; Naf Water Solutions Enterprises LLC; Naf Water Filtration LLCRelease of Security Interest
Nov 26, 2025
Reel 73042, frame 38
Chemtrac, Inc.Naf Contrco LLCNunc Pro Tunc Assignment
Nov 26, 2025
Reel 73042, frame 288
Naf Contrco LLCNorth American Filtration Holdings LLCNunc Pro Tunc Assignment
Nov 26, 2025
Reel 73042, frame 585
North American Filtration Holdings LLCNaf Water Solutions Enterprises LLCNunc Pro Tunc Assignment
Nov 26, 2025
Reel 73042, frame 830
Naf Water Solutions Enterprises LLCChemtrac LLCNunc Pro Tunc Assignment
May 7, 2026
Reel 74586, frame 152
North American Filtration Holdings LLC; Naf Water Filtration Enterprises LLC; Naf Water Filtration LLC; Naf Water Solution Enterprises LLC; Chemtrac LLC; Naf Aquatics LLCJpmorgan Chase Bank, N.a.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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