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Clarification and Sorptive-Filtration System for the Capture of Constituents and Particulate Matter in Liquids and Gases

US 7,524,422 Term ended
OverviewSources & methods

Term ended Nov 16, 2020 · Medium confidence

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

USPTO later recorded it as expired for non-payment on May 31, 2021.

Held by Unit Process Technologies, LLC
Filed Aug 22, 2007 as application 11/843,485 · Granted Apr 28, 2009
Base term, 20 years from filing
Today
20 years from filing
Term ended Nov 16, 2020
2000 2026
Clock starts
Nov 16, 2000
Term ended
Nov 16, 2020
Granted
Apr 28, 2009
base term 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
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.

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.
Step Input Date after this step Confidence
Base term, 20 years from filingClock starts Nov 16, 2000, when the earliest non-provisional application in its chain was filed (this one was filed Aug 22, 2007); a parent in its chain could not be resolved (the next row)Nov 16, 2020High 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 paidterm endedHigh confidence
USPTO status recordRecorded as expired for non-payment on May 31, 2021, after the term endedno changeHigh confidence
Computed term endThe steps above, in orderNov 16, 2020Medium confidence

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.

Not on this page: the patent's family, its recorded assignments and its citation count. USPTO's assignment records, linked above, list every recorded assignment.

Every date shows its work: the base term, any term adjustment or extension, any disclaimer cap, and the maintenance fee record, each with a confidence tier. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

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