Term ends Sep 8, 2031 · High confidence
20-year base term ends Sep 8, 2031
Held by NHK Spring Co., Ltd.
Filed Sep 8, 2011 as application 13/228,146 · Granted Oct 15, 2013
Base term, 20 years from filing
Today
2011
2031
Clock starts
Sep 8, 2011
Sep 8, 2011
Term ends
Sep 8, 2031
Sep 8, 2031
Granted
Oct 15, 2013
Oct 15, 2013
base term
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
None
Term adjustment
No prosecution delay on this record.
None
Terminal disclaimer
No disclaimer on this record.
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.
72
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. 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.
| Step | Input | Date after this step | Confidence |
|---|---|---|---|
| Base term, 20 years from filing | Clock starts Sep 8, 2011, when this application, 13/228,146, was filed | Sep 8, 2031 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | None on file | no change | 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 | 3 of 3 maintenance fees paid | In force | High confidence |
| Computed term end | The steps above, in order | Sep 8, 2031 | High confidence |
This family
| US 10,109,306 | In force Mar 2031 | Mar 2031 |
| US 9,047,895 | In force Jun 2031 | Jun 2031 |
| US 8,559,137 | this patent Sep 2031 | Sep 2031 |
| US 8,859,039 | In force Apr 2032 | Apr 2032 |
| US 9,318,135 | In force Dec 2034 | Dec 2034 |
| US 9,536,551 | In force May 2034 | May 2034 |
| US 9,339,941 | In force Jan 2034 | Jan 2034 |
| US 9,230,581 | In force Dec 2033 | Dec 2033 |
8 of 72 applications in this family shown, earliest filings first. 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 |
|---|---|---|---|
| Sep 8, 2011 Reel 26874, frame 704 | Imuta, Shogo | NHK Spring Co., Ltd. | 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.
Free plan: 3 watched companies. Pro: unlimited.
Alerts on its grants, lapses and transfers.
What's changing
Sep 2031
Term ends Sep 8, 2031. No further fees fall due before then
Citations
44
later US patents cite this one
That is top 25% of utility patents granted in 2013 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.
In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.