Patent US2531433A successfully refreshed from Google Patents.
US2531433A
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US
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Time sharing duplex communication system
Assignee: STC PLC
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Filing: 1947-03-01
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Granted: 1950-11-28
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Expires: 1967-03-01
Abstract
No abstract record available.
Inventors
- 👤 Ross B Hoffman
- 👤 Robert C Ferrar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:00
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1433599A
Cited
US1489158A
Cited
US2098286A
Cited
US2199179A
Cited
US2410641A
Cited
US2408791A
Cited
US2425314A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |