Also listed on Chervon Limited, an earlier holder on the record. The recorded assignments below show how it moved.
Term ends Jul 14, 2031 · High confidence
20-year base term ends Oct 22, 2029
Held by Chervon (HK) Limited
Filed Oct 22, 2009 as application 12/589,326 · Granted Aug 5, 2014
Base term plus 630 days of patent term adjustment (USPTO delay)
Today
2009
2031
Clock starts
Oct 22, 2009
Oct 22, 2009
Term ends
Jul 14, 2031
Jul 14, 2031
Granted
Aug 5, 2014
Aug 5, 2014
base term
patent term adjustment
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
630
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
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.
This patent's term runs 630 days past its 20-year base term on 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 Oct 22, 2009, when this application, 12/589,326, was filed | Oct 22, 2029 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +630 days, USPTO patent term adjustment record | Jul 14, 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 | 3 of 3 maintenance fees paid | In force | High confidence |
| Computed term end | The steps above, in order | Jul 14, 2031 | High 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.
| Recorded | Assignor | Assignee | Conveyance |
|---|---|---|---|
| Dec 22, 2009 Reel 23687, frame 84 | Yamaoka, Toshinari; Xu, Haishen | Chervon Limited | Assignment of Assignor's Interest |
| Apr 20, 2016 Reel 38333, frame 750 | Chervon Limited | Chervon (HK) Limited | 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
Jul 2031
Term ends Jul 14, 2031. No further fees fall due before then
Note
The 630 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Citations
15
later US patents cite this one
That is above 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.
In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.