Lapsed Jun 7, 2023 on the fee record · High confidence
20-year base term ends Sep 19, 2028
Third maintenance fee unpaid; grace period ended.
Held by Spirent Communications, Inc.
Filed Sep 19, 2008 as application 12/234,450 · Granted Jun 7, 2011
Base term, 20 years from filing, plus 184 days of patent term adjustment (USPTO delay)
Today
Lapsed Jun 7, 2023
2008
2029
Clock starts
Sep 19, 2008
Sep 19, 2008
No longer in force
Jun 7, 2023
Jun 7, 2023
Granted
Jun 7, 2011
Jun 7, 2011
Term would have run to
Mar 22, 2029
Mar 22, 2029
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
184
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
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.
2
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 Mar 22, 2029: its 20-year base term plus 184 days of term adjustment for prosecution delay. 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 Sep 19, 2008, when this application, 12/234,450, was filed | Sep 19, 2028 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +184 days, USPTO patent term adjustment record | Mar 22, 2029 | 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 | 2 of 3 maintenance fees paid | lapsed Jun 7, 2023 | High confidence |
| Computed term end | The steps above, in order | Jun 7, 2023 | High confidence |
This family
| US 7,958,230 | this patent Jun 2023 | Jun 2023 |
| US 8,433,811 | In force Sep 2028 | Sep 2028 |
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 23, 2008 Reel 21574, frame 641 | Guruswamy, Kowsik; Maze, James | Mu Dynamics, Inc. | Assignment of Assignor's Interest |
| Jun 13, 2014 Reel 33099, frame 185 | Mu Dynamics, Inc. | Spirent Communications, Inc. | 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.
Free plan: 3 watched companies. Pro: unlimited.
Alerts on its grants, lapses and transfers.
What's changing
Note
The 184 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us
Citations
28
later US patents cite this one
That is top 25% of utility patents granted in 2011 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.