US2593419A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Class of line indication in telephone systems
Assignee: International Standard Electric Corp
•
Filing: 1947-05-22
•
Granted: 1952-04-22
•
Expires: 1967-05-22
Abstract
No abstract record available.
Inventors
- 👤 Hertog Martinus Den
- 👤 Berden Amedie Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:20
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/58; H04Q3/62; H04Q3/625
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2137409A
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US2372262A
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US2332872A
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US2348301A
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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) | 1955-04-22 | 1955-10-22 | 1956-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-22 | 1959-10-22 | 1960-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-22 | 1963-10-22 | 1964-04-22 | $7700.00 | Window Closed / Lapsed |