Also listed on SK Telecom Co., Ltd., an earlier holder on the record. The recorded assignments below show how it moved.
Term ends Nov 24, 2026 · High confidence
20-year base term ended Oct 20, 2024
Held by KT Corporation
Filed Oct 20, 2004 as application 10/970,208 · Granted Sep 23, 2008
Base term plus 765 days of patent term adjustment (USPTO delay)
Today
2004
2026
Clock starts
Oct 20, 2004
Oct 20, 2004
Term ends
Nov 24, 2026
Nov 24, 2026
Granted
Sep 23, 2008
Sep 23, 2008
base term
patent term adjustment
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
765
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 765 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 20, 2004, when this application, 10/970,208, was filed | Oct 20, 2024 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +765 days, USPTO patent term adjustment record | Nov 24, 2026 | 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 | Nov 24, 2026 | 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 |
|---|---|---|---|
| Mar 2, 2005 Reel 16315, frame 773 | Lee, Young-ha; Yu, Chang-wahn; Park, Youn-ok; Hwang, Seung-ku | Electronics and Telecommunications Research Institute; Samsung Electronics Co., Ltd.; SK Telecom Co., Ltd.; KT Corporation; Ktfreetel Co., Ltd.; Hanaro Telecom, Inc. | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | Electronics and Telecommunications Research Institute | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | Samsung Electronics Co., Ltd. | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | SK Telecom Co., Ltd. | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | KT Corporation | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | Ktfreetel Co., Ltd. | Assignment of Assignor's Interest |
| Mar 2, 2005 reel/frame not recorded | Hwang, Seung-ku; Lee, Young-ha; Park, Youn-ok; Yu, Chang-wahn | Hanaro Telecom, Inc. | Assignment of Assignor's Interest |
| Jul 20, 2009 Reel 22976, frame 32 | Ktfreetel Co., Ltd. | KT Corporation | Merger |
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
Nov 2026
Term ends Nov 24, 2026. No further fees fall due before then
Note
The 765 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Citations
39
later US patents cite this one
That is top 25% of utility patents granted in 2008 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.