US2997549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loudspeaker construction
Assignee: Individual
•
Filing: 1958-03-20
•
Granted: 1961-08-22
•
Expires: 1978-03-20
Abstract
No abstract record available.
Inventors
- 👤 Joseph A Hassan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:52
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/06; H04R9/02; H04R9/04; H04R9/045
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2429470A
Cited
FR827276A
Cited
US2439665A
Cited
FR907651A
Cited
US2513171A
Cited
US2641329A
Cited
US2768235A
Cited
US2845135A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-08-21 | 1965-02-20 | 1965-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-08-21 | 1969-02-20 | 1969-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-08-21 | 1973-02-20 | 1973-08-22 | $7700.00 | Window Closed / Lapsed |