Lapsed Aug 26, 2026 on the fee record · High confidence

Computed 20-year base term

Third maintenance fee unpaid; grace period ended.

Held by TDK Corporation

Filed Dec 21, 2012 as application 13/724,073 · Granted Aug 26, 2014

Base term, 20 years from filing, plus 6 days of patent term adjustment (USPTO delay)

Today

Lapsed Aug 26, 2026

2011 2031

Clock starts
Jun 13, 2011

No longer in force
Aug 26, 2026

Granted
Aug 26, 2014

Term would have run to
Jun 19, 2031

base term after the term ends 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

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.

Family applications on record here

Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Jun 19, 2031: its 20-year base term plus 6 days of term adjustment for prosecution delay. 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.

Step	Input	Date after this step	Confidence
Base term, 20 years from filing	Clock starts Jun 13, 2011, when application 13/159,011, the earliest non-provisional in its chain, was filed (this one was filed Dec 21, 2012)	Jun 13, 2031	High confidence
Continuity chain	Every parent in the chain resolved	no change	High confidence
Patent term adjustment	+6 days, USPTO patent term adjustment record	Jun 19, 2031	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 26, 2026	High confidence
Computed term end	The steps above, in order	Aug 26, 2026	High confidence

This family

US 8,929,098	In force May 2033	May 2033
US 8,830,700	Lapsed on the fee record Sep 2026	Sep 2026
US 8,830,701	Lapsed on the fee record Sep 2026	Sep 2026
US 8,817,490	this patent Aug 2026	Aug 2026

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.

Recorded	Assignor	Assignee	Conveyance
Dec 21, 2012 Reel 29518, frame 578	Takegami, Eiji; Kawakami, Jun; Kamono, Takeshi	TDK Corporation	Assignment of Assignor's Interest
Jul 17, 2013 Reel 30820, frame 995	TDK Corporation	TDK Corporation	Change of Address

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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Alerts on its grants, lapses and transfers.

What's changing

Note

The 6 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us

Citations

later US patents cite this one

That is below the median of utility patents granted in 2014 in our data, the only group it is compared against. How we rank

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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