Also listed on KNFB Reader, LLC, an earlier holder on the record. The recorded assignments below show how it moved.
Term ends Jan 1, 2027 · High confidence
20-year base term ended Apr 1, 2025
Filed Apr 1, 2005 as application 11/097,944 · Granted Mar 17, 2009
Base term plus 640 days of patent term adjustment (USPTO delay)
Today
2005
2027
Clock starts
Apr 1, 2005
Apr 1, 2005
Term ends
Jan 1, 2027
Jan 1, 2027
Granted
Mar 17, 2009
Mar 17, 2009
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
640
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 640 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 Apr 1, 2005, when this application, 11/097,944, was filed | Apr 1, 2025 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +640 days, USPTO patent term adjustment record | Jan 1, 2027 | 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 | Jan 1, 2027 | 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 7, 2005 Reel 16864, frame 996 | National Federation of the Blind | K-NFB Reading Technology, Inc. | Assignment of Assignor's Interest |
| Dec 7, 2005 Reel 16865, frame 3 | Gashel, James | National Federation for the Blind | Assignment of Assignor's Interest |
| Dec 8, 2005 Reel 16869, frame 310 | Gashel, James | National Federation of the Blind | Corrective Assignment to Correct the Assignee's Name Previously Recorded on Reel 016865 Frame 0003. Assignor(S) Hereby Confirms the Name of the Assignee Is National Federation of the Blind. |
| Mar 6, 2006 Reel 17307, frame 248 | Kurzweil, Raymond C.; Albrecht, Paul; Gibson, Lucy | Kurzweil Technologies, Inc. | Assignment of Assignor's Interest |
| Mar 6, 2006 Reel 17307, frame 588 | Kurzweil Technologies, Inc. | K-NFB Reading Technology, Inc. | Assignment of Assignor's Interest |
| Mar 21, 2013 Reel 30058, frame 669 | K-NFB Reading Technology, Inc. | K-NFB Holding Technology, Inc. | Change of Name |
| Mar 21, 2013 Reel 30059, frame 351 | K-NFB Holding Technology, Inc. | K-NFB Reading Technology, Inc. | Assignment of Assignor's Interest |
| Apr 29, 2015 Reel 35522, frame 289 | K-NFB Reading Technology, Inc. | KNFB Reader, LLC | Assignment of Assignor's Interest |
| May 1, 2015 Reel 35546, frame 143 | KNFB Reader, LLC | Dimensional Stack Assets LLC | License |
| Jan 27, 2016 Reel 37603, frame 342 | Fish & Richardson P.C. | KNFB Reader, LLC | Release and Termination of Liens |
| Jan 6, 2022 Reel 58577, frame 914 | KNFB Reader, LLC | The National Federation of the Blind | 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
Jan 2027
Term ends Jan 1, 2027. No further fees fall due before then
Note
The 640 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Citations
65
later US patents cite this one
That is top 25% 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.
In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.