Term ended no later than Feb 23, 2026 · Medium confidence
20-year base term ended Jun 4, 2025
USPTO later recorded it as expired for non-payment on Sep 21, 2026.
Held by Spintech, LLC
Filed Jul 15, 2011 as application 13/183,508 · Granted Aug 19, 2014
Base term plus 264 days of patent term adjustment (USPTO delay)
Today
Ended no later than Feb 23, 2026
2005
2026
Clock starts
Jun 4, 2005
Jun 4, 2005
Ended no later than
Feb 23, 2026
Feb 23, 2026
Granted
Aug 19, 2014
Aug 19, 2014
base term
patent term adjustment
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
264
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
Unresolved
Terminal disclaimer
On file, reference document not resolved, so the date above is an upper bound. We do not guess the cap.
2 of 2
Maintenance fees paid
Two maintenance fees can end this term early, the ones due 3.5 and 7.5 years from grant; the third one's grace period runs past the term end. This counts the ones the record shows paid.
8
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 runs 264 days past its 20-year base term on prosecution delay. A terminal disclaimer is on file with no resolved reference, so no cap is applied and none is guessed. Confidence: Medium. 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 4, 2005, when application PCT/US2005/019842, the earliest non-provisional in its chain, was filed (this one was filed Jul 15, 2011) | Jun 4, 2025 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +264 days, USPTO patent term adjustment record | Feb 23, 2026 | High confidence |
| Terminal disclaimer cap | Disclaimer on file (approved), reference document not resolved | no cap applied, and none guessed | Medium confidence |
| Patent term extension | None on file | no change | High confidence |
| Fee events | 2 of 2 maintenance fees paid | term ended | High confidence |
| USPTO status record | Recorded as expired for non-payment on Sep 21, 2026, after the term ended | no change | High confidence |
| Computed term end | The steps above, in order | no later than Feb 23, 2026 | Medium confidence |
This family
| Application PCT/US2005/019842 | PCT application no patent term | no patent term |
| US 7,981,229 | In force Dec 2026 | Dec 2026 |
| US 8,101,689 | In force no later than Aug 2027 | no later than Aug 2027 |
| US 7,938,923 | In force Dec 2026 | Dec 2026 |
| Application 12/719,197 | Abandoned not computed | not computed |
| Application 12/755,868 | Abandoned not computed | not computed |
| US 8,808,479 | this patent no later than Feb 2026 | no later than Feb 2026 |
7 of 8 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 |
|---|---|---|---|
| Jul 19, 2011 Reel 26613, frame 805 | Hood, Patrick J. | Cornerstone Research Group, Inc. | Assignment of Assignor's Interest |
| Jan 11, 2018 Reel 44595, frame 144 | Cornerstone Research Group Inc. | Spintech, LLC | 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.
What's changing
Note
A terminal disclaimer is on file and its reference is not resolved. No cap is applied and none is guessed
Note
The 264 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Open question
A terminal disclaimer is on file (approved) and its reference document is not resolved. A disclaimer would cap the term earlier than Feb 23, 2026. We will not guess the cap.
Citations
3
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
This computed term ends no later than the date shown; an unresolved terminal disclaimer may end it earlier. Related patents and pending applications may cover overlapping subject matter.