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US

3-D Optical Microscope

US 7,944,609 In force
OverviewFamilyAssignmentsSources & methods

Also listed on Kla Corporation, an earlier holder on the record. The recorded assignments below show how it moved.

Term ends May 26, 2027 · High confidence

Filed Feb 3, 2010 as application 12/699,821 · Granted May 17, 2011
Base term, 20 years from filing
Today
20 years from filing
2007 2027
Clock starts
May 26, 2007
Term ends
May 26, 2027
Granted
May 17, 2011
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.
No effect
Terminal disclaimer
Resolved from the filed document, referencing US 7,729,049, to May 26, 2027. The term already ends on or before that date, so the cap shortened nothing.
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.
4
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. A terminal disclaimer is resolved from the filed document, and it ends no earlier than this term, so it shortens nothing. 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 26, 2007, when application 11/754,282, the earliest non-provisional in its chain, was filed (this one was filed Feb 3, 2010)May 26, 2027High 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 7,729,049)resolves to May 26, 2027, no earlier than this term, so no changeHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderMay 26, 2027High confidence

This family

US 7,729,049In force
Jan 2028
Jan 2028
US 8,184,364In force
Apr 2029
Apr 2029
US 7,944,609this patent
May 2027
May 2027
US 8,174,762In force
May 2027
May 2027
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 1, 2018
Reel 46530, frame 323
Zeta Instruments, Inc.Kla-Tencor CorporationAssignment 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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