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US

Electromagnetic Surveying

US 8,265,913 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 Jun 6, 2030 · High confidence

Filed May 21, 2007 as application 11/751,220 · Granted Sep 11, 2012
Base term plus 1112 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2007 2030
Clock starts
May 21, 2007
Term ends
Jun 6, 2030
Granted
Sep 11, 2012
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
1,112
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.

This patent's term runs 1112 days past its 20-year base term on 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 May 21, 2007, when this application, 11/751,220, was filedMay 21, 2027High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+1112 days, USPTO patent term adjustment recordJun 6, 2030High 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 orderJun 6, 2030High 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
Jun 5, 2007
Reel 19384, frame 129
Macgregor, Lucy; Andreis, David; Barker, NevilleOhm 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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