Lapsed Aug 2, 2017 on the fee record · Medium confidence
20-year base term ended Oct 15, 2019
Why Medium: A terminal disclaimer is on file (approved) with no resolved reference, so the term may end earlier.
Third maintenance fee unpaid; grace period ended.
Held by Memjet Technology Limited
Filed Apr 16, 2001 as application 09/835,472 · Granted Aug 2, 2005
Base term, 20 years from filing, plus 759 days of patent term adjustment (USPTO delay)
Today
Lapsed Aug 2, 2017
1999
2026
Clock starts
Oct 15, 1999
Oct 15, 1999
No longer in force
Aug 2, 2017
Aug 2, 2017
Granted
Aug 2, 2005
Aug 2, 2005
Term would have run to
Nov 12, 2021
Nov 12, 2021
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
759
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 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.
1,425
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.
Its term would have run to Nov 12, 2021: its 20-year base term plus 759 days of term adjustment for 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 Oct 15, 1999, when application PCT/AU1999/000894, the earliest non-provisional in its chain, was filed (this one was filed Apr 16, 2001) | Oct 15, 2019 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +759 days, USPTO patent term adjustment record | Nov 12, 2021 | 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 3 maintenance fees paid | lapsed Aug 2, 2017 | High confidence |
| Computed term end | The steps above, in order | Aug 2, 2017 | Medium confidence |
This family
| US 6,464,340 | Term ended Aug 2018 | Aug 2018 |
| US 6,918,655 | Lapsed on the fee record Jul 2017 | Jul 2017 |
| US 6,938,989 | Lapsed on the fee record Sep 2013 | Sep 2013 |
| US 6,742,873 | Lapsed on the fee record Jun 2016 | Jun 2016 |
| US 6,923,526 | this patent Aug 2017 | Aug 2017 |
| US 6,588,882 | Lapsed on the fee record Jul 2015 | Jul 2015 |
| US 6,505,912 | Term ended no later than Jul 2018 | no later than Jul 2018 |
| US 6,485,123 | Lapsed on the fee record Nov 2014 | Nov 2014 |
8 of 1425 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 |
|---|---|---|---|
| Sep 10, 2001 Reel 12156, frame 977 | Silverbrook, Kia | Silverbrook Research Pty Ltd. | Assignment of Assignor's Interest |
| Jul 12, 2012 Reel 28539, frame 484 | Silverbrook Research Pty. Limited and Clamate Pty Limited | Zamtec Limited | Assignment of Assignor's Interest |
| Jun 25, 2014 Reel 33244, frame 276 | Zamtec Limited | Memjet Technology Limited | Change of Name |
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
A terminal disclaimer is on file and its reference is not resolved. No cap is applied and none is guessed
Note
The 759 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 Aug 2, 2017. We will not guess the cap.
Citations
22
later US patents cite this one
That is above the median of utility patents granted in 2005 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.