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US

Sorbents for the Oxidation and Removal of Mercury

US 7,435,286 Term ended
OverviewFamilyAssignmentsSources & methods

Term ended Mar 18, 2026 · High confidence

Filed Aug 22, 2005 as application 11/209,163 · Granted Oct 14, 2008
Base term plus 208 days of patent term adjustment (USPTO delay)
Today
20 years from filing
Term ended Mar 18, 2026
2005 2026
Clock starts
Aug 22, 2005
Term ended
Mar 18, 2026
Granted
Oct 14, 2008
base term patent term adjustment 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
208
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
3 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.
28
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 208 days past its 20-year base term on prosecution delay. All three maintenance fees were paid, so no fee lapse ended it. 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 Aug 22, 2005, when this application, 11/209,163, was filedAug 22, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+208 days, USPTO patent term adjustment recordMar 18, 2026High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidterm endedHigh confidence
Computed term endThe steps above, in orderMar 18, 2026High confidence

This family

US 7,435,286this patent
Mar 2026
Mar 2026
US 8,173,566Term ended
Oct 2026
Oct 2026
Application 12/201,595Abandoned
not computed
not computed
US 8,168,147Term ended
Aug 2025
Aug 2025
US 8,652,235Term ended
Jan 2026
Jan 2026
US 8,440,585Lapsed on the fee record
May 2021
May 2021
US 8,512,655Term ended
Aug 2025
Aug 2025
US 8,821,819Term ended
Aug 2025
Aug 2025
8 of 28 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
Nov 22, 2005
Reel 16810, frame 286
Olson, Edwin S; Holems, Michael J; Pavlish, John HEnergy & Environmental Research CenterAssignment of Assignor's Interest
Feb 27, 2007
Reel 18937, frame 132
Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.Energy & Environmental Research CenterCorrective Assignment to Correct the Spelling of the Last Name of Inventor Michael J. Holmes Previously Recorded on Reel 016810 Frame 0286. Assignor(S) Hereby Confirms the Assignment of Assignors' Interest..
Mar 16, 2007
Reel 19023, frame 539
Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.Energy & Environmental Research Center FoundationCorrective Assignment to Correct the Addition of the Word "Foundation" After the Word "Center" in Receiving Party Previously Recorded on Reel 018937 Frame 0132. Assignor(S) Hereby Confirms the Assignment of Assignors' Interest.
Jun 26, 2008
Reel 21154, frame 528
University of North Dakota, Energy & Environmental Resch Center FoundationEnergy, United States Department OfConfirmatory License
Aug 29, 2014
Reel 33643, frame 339
Pavlish, John H.Energy and Environmental Research Center FoundationAssignment of Assignor's Interest
Aug 29, 2014
Reel 33643, frame 436
Olson, Edwin S.Energy and Environmental Research Center FoundationAssignment of Assignor's Interest
Aug 29, 2014
Reel 33643, frame 538
Holmes, Michael J.Energy and Environmental Research Center FoundationAssignment of Assignor's Interest
Sep 9, 2014
Reel 33698, frame 612
Olson, Edwin S.Energy and Environmental Research Center FoundationCorrective Assignment to Correct the Receiving Party's Address Previously Recorded on Reel 033643 Frame 0436. Assignor(S) Hereby Confirms the Assignment.
Jun 8, 2017
Reel 42647, frame 351
Energy and Environmental Research Center FoundationMidwest Energy Emissions Corp.Assignment of Assignor's Interest
Mar 11, 2020
Reel 52144, frame 657
Energy and Environmental Research Center FoundationMidwest Energy Emissions Corp.Corrective Assignment to Correct the Correct the Address of the Receiving Party Previously Recorded on Reel 042647 Frame 0351. Assignor(S) Hereby Confirms the Assignment.
Nov 7, 2024
Reel 69187, frame 413
Midwest Energy Emissions Corp.Birchtech Corp.Change of Name

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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