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US

Sodium Nitrite Oxidation of Hydrogen Sulfide

US 11,383,994 In force
OverviewFamilyAssignmentsSources & methods

Term ends Mar 31, 2029 · High confidence

Filed Jul 28, 2020 as application 16/941,319 · Granted Jul 12, 2022
Base term plus 23 days of patent term adjustment (USPTO delay) · capped by a resolved terminal disclaimer
Today
20 years from filing
2009 2029
Clock starts
Mar 31, 2009
Term ends
Mar 31, 2029
Granted
Jul 12, 2022
base term 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
23
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
Capped
Terminal disclaimer
Resolved from the filed document, referencing US 10,065,874, US 10,723,641, US 8,702,994.
1 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 23 days past its 20-year base term on prosecution delay. A terminal disclaimer resolved from the filed document caps it earlier. 1 of 1 maintenance fees is paid so far. 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 Mar 31, 2009, when application 12/415,283, the earliest non-provisional in its chain, was filed (this one was filed Jul 28, 2020)Mar 31, 2029High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+23 days, USPTO patent term adjustment recordApr 23, 2029High confidence
Terminal disclaimer capDisclaimer resolved from the filed document (refs US 10,065,874, US 10,723,641, US 8,702,994)capped to Mar 31, 2029High confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events1 of 1 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderMar 31, 2029High 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 11,383,994this patent
Mar 2029
Mar 2029
US 12,391,588In force
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
Oct 6, 2021
Reel 57718, frame 959
Frost, Jack G.; Snyder, Kenneth J.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.

The Patent Finder CompaniesExpirationsCalculatorWatchlistPricing MethodologyCorrectionsLegalPrivacysupport@thepatentfinder.com Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) Part of 137 Finder · © 2026 137 Finder LLC · Sources cited