Electro-magnetic closed-loop speed control for air-turbine spindles

US 7,989,972 Lapsed on the fee record

Overview Sources & methods

Lapsed Aug 2, 2023 on the fee record · From the USPTO record

Computed 20-year base term

Third maintenance fee unpaid; grace period ended.

Named at grant Microlution Inc. · find this owner

Filed Oct 23, 2006 as application 11/551,967 · Granted Aug 2, 2011

Base term, 20 years from filing, plus 1286 days of patent term adjustment (USPTO delay)

Today

Lapsed Aug 2, 2023

2006 2030

Clock starts
Oct 23, 2006

No longer in force
Aug 2, 2023

Granted
Aug 2, 2011

Term would have run to
May 1, 2030

base term patent term adjustment after the term ends fee events 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

1,286

Days of term adjustment

Read from the USPTO patent term adjustment record, not recalculated here.

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.

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 filing	Clock starts Oct 23, 2006, when this application, 11/551,967, was filed	Oct 23, 2026	High confidence
Continuity chain	Every parent in the chain resolved	no change	High confidence
Patent term adjustment	+1286 days, USPTO patent term adjustment record	May 1, 2030	High confidence
Terminal disclaimer cap	None on record	no cap applied	High confidence
Patent term extension	None on file	no change	High confidence
Fee events	2 of 3 maintenance fees paid	lapsed Aug 2, 2023	High confidence
Computed term end	The steps above, in order	Aug 2, 2023	From the USPTO record

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.

Electro-magnetic closed-loop speed control for air-turbine spindles

Lapsed Aug 2, 2023 on the fee record · From the USPTO record

20-year base term ended Oct 23, 2026

How we calculated this date

Sources