Collateral for a security interest recorded Sep 12, 2025 (Barclays Bank PLC).
Term ended Sep 13, 2026 · High confidence
20-year base term ended Dec 10, 2021
Held by Altera Corporation
Filed Dec 10, 2001 as application 10/013,825 · Granted Oct 13, 2009
Base term plus 1738 days of patent term adjustment (USPTO delay)
Today
Term ended Sep 13, 2026
2001
2026
Clock starts
Dec 10, 2001
Dec 10, 2001
Term ended
Sep 13, 2026
Sep 13, 2026
Granted
Oct 13, 2009
Oct 13, 2009
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
1,738
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 1738 days past its 20-year base term on prosecution delay. All three maintenance fees were paid, so no fee lapse ended it. 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 Dec 10, 2001, when this application, 10/013,825, was filed | Dec 10, 2021 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +1738 days, USPTO patent term adjustment record | Sep 13, 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 | term ended | High confidence |
| Computed term end | The steps above, in order | Sep 13, 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 |
|---|---|---|---|
| Apr 29, 2002 Reel 12886, frame 1 | Quicksilver Technology Incorporated | Techfarm Ventures, L.p.; Techfarm Ventures (Q) L.P.; Emerging Alliance Fund L.P.; Selby Ventures Partners II, L.P.; Wilson Sonsini Goodrich & Rosati, P.C. | Security Interest |
| Apr 29, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures, L.p. | Security Interest |
| Apr 29, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures (Q) L.P. | Security Interest |
| Apr 29, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Emerging Alliance Fund L.P. | Security Interest |
| Apr 29, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Selby Ventures Partners II, L.P. | Security Interest |
| Apr 29, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Wilson Sonsini Goodrich & Rosati, P.C. | Security Interest |
| May 9, 2002 Reel 12897, frame 780 | Master, Paul L.; Watson, John | Quicksilver Technology, Inc. | Assignment of Assignor's Interest |
| May 24, 2002 Reel 12951, frame 764 | Quicksilver Technology Incorporated | Techfarm Ventures, L.p.; Techfarm Ventures (Q), L.P.; Emerging Alliance Fund L.P.; Selby Venture Partners II, L.P.; Wilson Sonsini Goodrich & Rosati, P.C.; Portview Communications Partners L.P. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures, L.p. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures (Q), L.P. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Emerging Alliance Fund L.P. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Selby Venture Partners II, L.P. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Wilson Sonsini Goodrich & Rosati, P.C. | Security Agreement |
| May 24, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Portview Communications Partners L.P. | Security Agreement |
| Jun 18, 2002 Reel 13422, frame 294 | Quicksilver Technology Incorporated | Techfarm Ventures, L.p.; Techfarm Ventures, L.P., as Agent for the Benefit Of:; Techfarm Ventures (Q), L.P.; Emerging Alliance Fund L.P.; Selby Venture Partners II, L.P.; Wilson Sonsini Goodrich & Rosati, P.C.; Portview Communications Partners L.P. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures, L.p. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures, L.P., as Agent for the Benefit Of: | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Techfarm Ventures (Q), L.P. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Emerging Alliance Fund L.P. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Selby Venture Partners II, L.P. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Wilson Sonsini Goodrich & Rosati, P.C. | Security Agreement |
| Jun 18, 2002 reel/frame not recorded | Quicksilver Technology Incorporated | Portview Communications Partners L.P. | Security Agreement |
| Oct 6, 2006 Reel 18367, frame 729 | Techfarm Ventures, L.P., as Agent; Techfarm Ventures, L.p.; Techfarm Ventures (Q), L.P.; Emerging Alliance Fund, L.p.; Selby Venture Partners II, L.P.; Portview Communications Partners L.P.; Wilson Sonsini Goodrich & Rosati, P.C. | Quicksilver Technology, Inc. | Release of Security Interest in Patents |
| Oct 16, 2006 Reel 18407, frame 637 | Quicksilver Technology, Inc. | Techfarm Ventures Management, LLC | Assignment of Assignor's Interest |
| Oct 5, 2007 Reel 19927, frame 230 | Techfarm Ventures Management LLC | QST Holdings, LLC | Assignment of Assignor's Interest |
| Mar 15, 2013 Reel 30011, frame 209 | QST Holdings, LLC | Altera Corporation | Assignment of Assignor's Interest |
| Sep 12, 2025 Reel 73431, frame 309 | Altera Corporation | Barclays Bank PLC, as Collateral Agent | Security 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
Note
The 1738 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Citations
4
later US patents cite this one
That is below the median of utility patents granted in 2009 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.