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US

Methods and Systems for Drilling

US 8,939,233 In force
OverviewFamilyAssignmentsSources & methods

Term ends Apr 11, 2031 · Medium confidence

Why Medium: A parent in the chain could not be resolved.

Filed Oct 11, 2012 as application 13/649,434 · Granted Jan 27, 2015
Base term, 20 years from filing
Today
20 years from filing
2011 2031
Clock starts
Apr 11, 2011
Term ends
Apr 11, 2031
Granted
Jan 27, 2015
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.
2 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.
8
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 is its 20-year base term, with no adjustment for prosecution delay. 2 of 3 maintenance fees are paid so far. 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 Apr 11, 2011, when application PCT/US2011/031920, the earliest non-provisional in its chain, was filed (this one was filed Oct 11, 2012); a parent in its chain could not be resolved (the next row)Apr 11, 2031High confidence
Continuity chainA parent in the chain could not be resolveddated from this application's own claimMedium confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderApr 11, 2031Medium confidence

This family

Application PCT/US2011/031920PCT application
no patent term
no patent term
Application 13/649,462Abandoned
not computed
not computed
US 8,561,720In force
Apr 2031
Apr 2031
US 9,683,418In force
Apr 2033
Apr 2033
US 9,879,490In force
Apr 2031
Apr 2031
US 8,939,233this patent
Apr 2031
Apr 2031
US 9,470,052In force
Mar 2032
Mar 2032
US 10,415,365In force
Sep 2031
Sep 2031
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
Dec 9, 2014
Reel 34441, frame 274
Edbury, David Alston; Guerrero, Jose Victor; Macdonald, Duncan Charles; Rogers, James Byron; Sitton, Donald RayShell Oil CompanyAssignment of Assignor's Interest
Mar 7, 2022
Reel 59694, frame 819
Shell Oil CompanyShell USA, Inc.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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