US2509829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Duplex telegraph system
Assignee: FR SADIR CARPENTIER SOC
•
Filing: 1947-08-11
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Granted: 1950-05-30
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Expires: 1967-08-11
Abstract
No abstract record available.
Inventors
- 👤 Calvez Philippe Yves Marie Le
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:35
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/12; H04L1/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2235755A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-05-29 | 1953-11-28 | 1954-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-05-29 | 1957-11-28 | 1958-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-05-29 | 1961-11-28 | 1962-05-30 | $7700.00 | Window Closed / Lapsed |