The Patent Finder
US

Acid Mixing System

US 11,992,591 In force
OverviewSources & methods

Term ends Aug 18, 2039 · High confidence

Held by Isopure, Corp.
Filed Jun 28, 2021 as application 17/360,419 · Granted May 28, 2024
Base term plus 514 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2018 2039
Clock starts
Mar 22, 2018
Term ends
Aug 18, 2039
Granted
May 28, 2024
base term patent term adjustment 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
514
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
0 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.

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 Mar 22, 2018, when the earliest non-provisional application in its chain was filed (this one was filed Jun 28, 2021)Mar 22, 2038High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+514 days, USPTO patent term adjustment recordAug 18, 2039High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events0 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderAug 18, 2039High 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.

In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.

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