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System and Method of Slurry Treatment

US 7,488,423 Term ended
OverviewFamilyAssignmentsSources & methods

Term ended Dec 17, 2025 · High confidence

Filed Aug 2, 2005 as application 11/195,108 · Granted Feb 10, 2009
Base term plus 137 days of patent term adjustment (USPTO delay)
Today
20 years from filing
Term ended Dec 17, 2025
2005 2026
Clock starts
Aug 2, 2005
Term ended
Dec 17, 2025
Granted
Feb 10, 2009
base term patent term adjustment after the term ends fee events Updated Nov 15, 2026 · includes USPTO assignment & status data published Nov 15, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
137
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.
5
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 137 days past its 20-year base term on prosecution delay. All three maintenance fees were paid, so no fee lapse ended it. 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 Aug 2, 2005, when this application, 11/195,108, was filedAug 2, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+137 days, USPTO patent term adjustment recordDec 17, 2025High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidterm endedHigh confidence
Computed term endThe steps above, in orderDec 17, 2025High confidence

This family

US 7,604,725In force
Apr 2027
Apr 2027
US 7,390,399Lapsed on the fee record
Jun 2016
Jun 2016
US 7,488,423this patent
Dec 2025
Dec 2025
Application PCT/US2006/026336PCT application
no patent term
no patent term
US 7,867,401Term ended
Jun 2025
Jun 2025
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 2, 2005
Reel 16867, frame 27
Wismer, Michael W.; Woodling, Richard; Day, Richard C.Usfilter CorporationAssignment of Assignor's Interest
Oct 20, 2006
Reel 18418, frame 212
Usfilter CorporationSiemens Water Technologies Holding Corp.Change of Name
Apr 15, 2011
Reel 26138, frame 593
Siemens Water Technologies Holding Corp.Siemens Industry, Inc.Merger
Jan 1, 2014
Reel 31896, frame 256
Siemens Industry, Inc.Siemens Water Technologies LLCAssignment of Assignor's Interest
Jan 24, 2014
Reel 32126, frame 430
WTG Holdings III Corp.; WTG Holdings II Corp.; Siemens Treated Water Outsourcing Corp.; Siemens Water Technologies LLCCredit Suisse AG, Cayman Islands Branch, as Collateral AgentIntellectual Property Security Agreement (Second Lien)
Jan 24, 2014
Reel 32126, frame 487
WTG Holdings III Corp.; WTG Holdings II Corp.; Siemens Treated Water Outsourcing Corp.; Siemens Water Technologies LLCCredit Suisse AG, Cayman Islands Branch, as Collateral AgentIntellectual Property Security Agreement (First Lien)
Feb 7, 2014
Reel 32174, frame 282
Siemens Water Technologies LLCEvoqua Water Technologies LLCChange of Name
Apr 6, 2021
Reel 55845, frame 245
Credit Suisse AG, Cayman Islands Branch, as Collateral AgentSiemens Water Technologies LLCRelease of Security Interest (Reel/Frame 032126/0487)
Apr 6, 2021
Reel 55845, frame 311
Credit Suisse AG, Cayman Islands Branch, as Collateral AgentSiemens Water Technologies LLCRelease of Security Interest (Reel/Frame 032126/0430)
Apr 7, 2021
Reel 55848, frame 689
Evoqua Water Technologies LLC; Neptune Benson, Inc.JPMorgan Chase Bank, N.A., as Collateral AgentSecurity Interest
May 26, 2023
Reel 63787, frame 943
JPMorgan Chase Bank N.A., as Collateral AgentEvoqua Water Technologies LLC; Neptune Benson, Inc.Release of Security Interest
May 26, 2023
reel/frame not recorded
JPMorgan Chase Bank N.A., as Collateral AgentEvoqua Water Technologies LLCRelease of Security Interest
May 26, 2023
reel/frame not recorded
JPMorgan Chase Bank N.A., as Collateral AgentNeptune Benson, Inc.Release of 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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