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Process for Regenerating a Spent Sorbent

US 8,440,585 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed May 14, 2021 on the fee record · High confidence

Second maintenance fee unpaid; grace period ended.

Filed Mar 20, 2012 as application 13/425,288 · Granted May 14, 2013
Base term, 20 years from filing
Today
Lapsed May 14, 2021
2004 2026
Clock starts
Apr 23, 2004
No longer in force
May 14, 2021
Granted
May 14, 2013
Term would have run to
Apr 23, 2024
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.
No effect
Terminal disclaimer
Resolved from the filed document, referencing US 8,173,566, to Apr 23, 2024. The term already ends on or before that date, so the cap shortened nothing.
1 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.
28
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Apr 23, 2024: its 20-year base term, with no adjustment for prosecution delay. A terminal disclaimer is resolved from the filed document, and it ends no earlier than this term, so it shortens nothing. 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 Apr 23, 2004, when application PCT/US2004/012828, the earliest non-provisional in its chain, was filed (this one was filed Mar 20, 2012)Apr 23, 2024High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capDisclaimer resolved from the filed document (refs US 8,173,566)resolves to Apr 23, 2024, no earlier than this term, so no changeHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events1 of 2 maintenance fees paidlapsed May 14, 2021High confidence
Computed term endThe steps above, in orderMay 14, 2021High confidence

This family

US 7,435,286Term ended
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 8,440,585this patent
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
Aug 29, 2014
Reel 33643, frame 538
Holmes, Michael J.Energy and Environmental Research Center FoundationAssignment of Assignor's Interest
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
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

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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