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Sodium Nitrite Oxidation of Hydrogen Sulfide

US 12,391,588 In force, term unresolved
OverviewFamilyAssignmentsSources & methods

Term ends no later than May 5, 2030 · Medium confidence

In force on USPTO's status record and by its fee record. A terminal disclaimer on file may shorten this term, possibly to a date already past; its reference document is unresolved, so the date above is an upper bound and no earlier date is guessed.

Filed Jul 12, 2022 as application 17/863,243 · Granted Aug 19, 2025
Base term plus 400 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2009 2030
Clock starts
Mar 31, 2009
Ends no later than
May 5, 2030
Granted
Aug 19, 2025
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
400
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
Unresolved
Terminal disclaimer
On file, reference document not resolved, so the date above is an upper bound. We do not guess the cap.
0 of 1
Maintenance fees paid
One maintenance fee can end this term early, the one due 3.5 years from grant; the next one's grace period runs past the term end. This counts it if the record shows it paid.
7
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 400 days past its 20-year base term on prosecution delay. A terminal disclaimer is on file with no resolved reference, so no cap is applied and none is guessed. 0 of 1 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 Mar 31, 2009, when application 12/415,283, the earliest non-provisional in its chain, was filed (this one was filed Jul 12, 2022)Mar 31, 2029High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+400 days, USPTO patent term adjustment recordMay 5, 2030High confidence
Terminal disclaimer capDisclaimer on file (approved), reference document not resolvedno cap applied, and none guessedMedium confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events0 of 1 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderno later than May 5, 2030Medium confidence

This family

US 8,702,994In force
Oct 2031
Oct 2031
US 9,682,878In force
Mar 2029
Mar 2029
US 10,065,874In force
Mar 2029
Mar 2029
US 10,723,641In force
Mar 2029
Mar 2029
US 11,383,994In force
Mar 2029
Mar 2029
US 12,391,588this patent
no later than May 2030
no later than May 2030
Application 19/270,401Pending
not computed
not computed
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 15, 2022
Reel 61769, frame 146
Frost, Jack G; Snyder, Kenneth J, JR.United Laboratories International, LLCAssignment of Assignor's Interest
Mar 12, 2025
Reel 70491, frame 243
United Laboratories International, LLCTristar Global Energy Solutions, Inc.Merger
Mar 13, 2025
Reel 70508, frame 396
Tristar Global Energy Solutions, Inc.CR3 Zymeflow, Inc.Merger
Mar 15, 2025
Reel 70523, frame 169
CR3 Zymeflow, Inc.Zymeflow, Inc.Merger

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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