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Electrostatic Fluid Accelerator

US 7,652,431 Lapsed on the fee record
OverviewSources & methods

Lapsed Jan 26, 2014 on the fee record · Low confidence

First maintenance fee unpaid; grace period ended.

Held by Tessera, Inc.
Filed May 3, 2005 as application 11/119,748 · Granted Jan 26, 2010
Base term, 20 years from filing, plus 315 days of patent term adjustment (USPTO delay)
Today
Lapsed Jan 26, 2014
1999 2026
Clock starts
Oct 14, 1999
No longer in force
Jan 26, 2014
Granted
Jan 26, 2010
Term would have run to
Aug 24, 2020
base term patent term adjustment after the term ends Updated Nov 15, 2026 · includes USPTO assignment & status data published Nov 15, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
315
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
Unresolved
Terminal disclaimer
On file, reference document not resolved, so the date above is an upper bound. We do not guess the cap.
0 of 2
Maintenance fees paid
Two maintenance fees can end this term early, the ones due 3.5 and 7.5 years from grant; the third one's grace period runs past the term end. This counts the ones the record shows paid.

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.
Step Input Date after this step Confidence
Base term, 20 years from filingClock starts Oct 14, 1999, when the earliest non-provisional application in its chain was filed (this one was filed May 3, 2005); a parent in its chain could not be resolved (the next row)Oct 14, 2019High confidence
Continuity chainA parent in the chain could not be resolveddated from this application's own claimMedium confidence
Patent term adjustment+315 days, USPTO patent term adjustment recordAug 24, 2020High confidence
Terminal disclaimer capDisclaimer on file (approved), reference document not resolvedno cap applied, and none guessedMedium confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events0 of 2 maintenance fees paidlapsed Jan 26, 2014High confidence
Computed term endThe steps above, in orderJan 26, 2014Low confidence

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.

Not on this page: the patent's family, its recorded assignments and its citation count. USPTO's assignment records, linked above, list every recorded assignment.

Every date shows its work: the base term, any term adjustment or extension, any disclaimer cap, and the maintenance fee record, each with a confidence tier. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

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