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US2838741A
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Underwater sound detection system
Assignee: AT&T Inc
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Filing: 1953-04-27
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Granted: 1958-06-10
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Expires: 1973-04-27
Abstract
No abstract record available.
Inventors
- 👤 Warren P Mason
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:29
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/72
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-09 | 1961-12-09 | 1962-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-09 | 1965-12-09 | 1966-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-09 | 1969-12-09 | 1970-06-10 | $7700.00 | Window Closed / Lapsed |