US2967957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroacoustic transducer
Assignee: Individual
•
Filing: 1957-09-17
•
Granted: 1961-01-10
•
Expires: 1977-09-17
Abstract
No abstract record available.
Inventors
- 👤 Massa Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:58
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/10; B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0644; B06B1/0651
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2248870A
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US2105010A
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US2242756A
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US2430013A
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US2433383A
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US2472714A
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US2769867A
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US2472179A
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US2607858A
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US2614144A
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US2795648A
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US2894317A
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US2880497A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-01-10 | 1964-07-11 | 1965-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-01-10 | 1968-07-11 | 1969-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-01-10 | 1972-07-11 | 1973-01-10 | $7700.00 | Window Closed / Lapsed |