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US3525071A
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Electroacoustic transducer
Assignee: MASSA DONALD P COHASSET
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Filing: 1968-04-10
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Granted: 1970-08-18
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Expires: 1988-04-10
Abstract
No abstract record available.
Inventors
- 👤 Frank Massa Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:25
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0611; B06B1/0618
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2063951A
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US2181132A
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US2921288A
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US2963681A
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US2979690A
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US2748369A
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US2912856A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-08-17 | 1974-02-16 | 1974-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-08-17 | 1978-02-16 | 1978-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-08-17 | 1982-02-16 | 1982-08-18 | $7700.00 | Window Closed / Lapsed |