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US2894074A
Expired / Lapsed
US
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Telephone conference circuit
Assignee: General Dynamics Corp
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Filing: 1955-02-25
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Granted: 1959-07-07
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Expires: 1975-02-25
Abstract
No abstract record available.
Inventors
- 👤 Elliott George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:29
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/56
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1626034A
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US1554999A
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US2367110A
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US2333472A
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US2375678A
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US2588925A
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US2783373A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-07-06 | 1963-01-05 | 1963-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-07-06 | 1967-01-05 | 1967-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-07-06 | 1971-01-05 | 1971-07-07 | $7700.00 | Window Closed / Lapsed |