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US

Electromagnetic Surveying

US 7,565,245 In force
OverviewAssignmentsSources & methods

Also listed on Rock Solid Images, Inc., an earlier holder on the record. The recorded assignments below show how it moved.

Term ends Sep 20, 2027 · High confidence

Filed Sep 20, 2007 as application 11/858,239 · Granted Jul 21, 2009
Base term, 20 years from filing
Today
20 years from filing
2007 2027
Clock starts
Sep 20, 2007
Term ends
Sep 20, 2027
Granted
Jul 21, 2009
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
None
Term adjustment
No prosecution delay on this record.
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.

This patent's term is its 20-year base term, with no adjustment for prosecution delay. All three maintenance fees are recorded paid; no more fees are due. 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 Sep 20, 2007, when this application, 11/858,239, was filedSep 20, 2027High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderSep 20, 2027High 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
Oct 19, 2007
Reel 19989, frame 176
Andreis, David; Macgregor, Lucy; Golubev, NikolayOhm Ltd.Assignment of Assignor's Interest
Mar 25, 2011
Reel 26024, frame 241
Ohm LimitedOffshore Hydrocarbon Mapping PLCAssignment of Assignor's Interest
Sep 23, 2011
Reel 26956, frame 506
Offshore Hydrocarbon Mapping PLCRock Solid Images PLCChange of Name
Apr 27, 2015
Reel 35497, frame 896
Rock Solid Images PLCRock Solid Images, Inc.Assignment of Assignor's Interest
Jun 4, 2015
Reel 35783, frame 345
Rock Solid Images PLCRock Solid Images, Inc.Assignment of Assignor's Interest
Apr 8, 2020
Reel 52349, frame 588
SLLP 206 LimitedPGS Geophysical AsAssignment of Assignor's Interest
Apr 8, 2020
Reel 52351, frame 174
Rock Solid Images, Inc.; Rock Solid Images US Group, Inc.SLLP 206 LimitedDeed of Confirmation and Clarification

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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