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Method and Apparatus of Model-Based Photomask Synthesis

US 7,480,891 In force
OverviewAssignmentsSources & methods

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

Term ends Dec 27, 2026 · Medium confidence

Why Medium: The disclaimer's references carry disclaimers of their own not yet read (US 7,743,358), so the cap could be lower.

Filed Aug 13, 2005 as application 11/203,505 · Granted Jan 20, 2009
Base term plus 501 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2005 2026
Clock starts
Aug 13, 2005
Term ends
Dec 27, 2026
Granted
Jan 20, 2009
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
501
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
No effect
Terminal disclaimer
Resolved from the filed document, referencing US 7,743,358, to Dec 27, 2026. 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.

This patent's term runs 501 days past its 20-year base term on 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: 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 Aug 13, 2005, when this application, 11/203,505, was filedAug 13, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+501 days, USPTO patent term adjustment recordDec 27, 2026High confidence
Terminal disclaimer capDisclaimer resolved from the filed document (refs US 7,743,358)resolves to Dec 27, 2026, no earlier than this term, so no changeMedium confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderDec 27, 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
Oct 16, 2006
Reel 18396, frame 437
Sezginer, AbdurrahmanInvarium, Inc.Assignment of Assignor's Interest
Jun 19, 2008
Reel 21122, frame 542
Invarium, Inc.Cadence Design Systems, Inc.Assignment of Assignor's Interest
Mar 14, 2025
Reel 70519, frame 972
Cadence Design Systems, Inc.Silvaco, 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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