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Membrane Cleaning with Pulsed Airlift Pump

US 9,573,824 In force
OverviewFamilyAssignmentsSources & methods

Term ends May 29, 2028 · Medium confidence

Why Medium: A parent in the chain could not be resolved.

Filed Nov 26, 2013 as application 14/090,491 · Granted Feb 21, 2017
Base term, 20 years from filing
Today
20 years from filing
2008 2028
Clock starts
May 29, 2008
Term ends
May 29, 2028
Granted
Feb 21, 2017
base term 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
None
Term adjustment
No prosecution delay on this record.
None
Terminal disclaimer
No disclaimer on this record.
2 of 2
Maintenance fees paid
Two maintenance fees can end this term early, the ones due 3.5 and 7.5 years from grant; the third one's grace period runs past the term end. This counts the ones the record shows paid.
10
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. 2 of 2 maintenance fees are paid so far. Confidence: Medium. 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 May 29, 2008, when application PCT/US2008/006799, the earliest non-provisional in its chain, was filed (this one was filed Nov 26, 2013); a parent in its chain could not be resolved (the next row)May 29, 2028High confidence
Continuity chainA parent in the chain could not be resolveddated from this application's own claimMedium confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 2 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderMay 29, 2028Medium confidence

This family

Application 12/792,307Abandoned
not computed
not computed
US 8,287,743In force
May 2028
May 2028
US 8,622,222In force
May 2028
May 2028
US 8,372,276In force
May 2028
May 2028
Application 13/396,275Abandoned
not computed
not computed
US 8,840,783In force
Jul 2028
Jul 2028
US 9,573,824this patent
May 2028
May 2028
US 10,507,431In force
May 2029
May 2029
8 of 10 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
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 32173, frame 401
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)
Oct 16, 2026
Reel 76718, frame 189
Dupont Specialty Materials Singapore Pte. Ltd.Filmtec Water Singapore Pte. Ltd.Assignment 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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