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Protective Circuit for Intrinsically Safe Electro-Magnetic Actuators, and Protective Circuit for Intrinsically Safe Energy Supply Systems

US 7,872,846 In force, term unresolved
OverviewAssignmentsSources & methods

Term ends no later than Nov 25, 2026 · 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 Jan 27, 2006 as application 11/341,112 · Granted Jan 18, 2011
Base term plus 302 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2006 2026
Clock starts
Jan 27, 2006
Ends no later than
Nov 25, 2026
Granted
Jan 18, 2011
base term patent term adjustment 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
302
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.
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.

This patent's term runs 302 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. All three maintenance fees are recorded paid; no more fees are due. 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 Jan 27, 2006, when this application, 11/341,112, was filedJan 27, 2026High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+302 days, USPTO patent term adjustment recordNov 25, 2026High 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 events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderno later than Nov 25, 2026Medium confidence

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
Jan 27, 2006
Reel 17525, frame 44
Titschert, Jens; Sondermann, AchimDBT GmbHAssignment of Assignor's Interest
Nov 16, 2010
Reel 25375, frame 865
DBT GmbHBucyrus DBT Europe GmbHChange of Name
Dec 10, 2010
Reel 25492, frame 934
Bucyrus DBT Europe GmbHBucyrus Europe GmbHChange of Name
Sep 1, 2015
Reel 36526, frame 184
Bucyrus Europe GmbHCaterpillar Global Mining Europe GmbHChange of Name
Nov 22, 2022
Reel 61987, frame 528
Caterpillar Global Mining Europe GmbHCaterpillar Inc.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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