US2454809A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone system utilizing register controlled final selector switches
Assignee: International Standard Electric Corp
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Filing: 1943-01-16
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Granted: 1948-11-30
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Expires: 1963-01-16
Abstract
No abstract record available.
Inventors
- 👤 Kruithof Jacob
- 👤 Kozma Ladislas
- 👤 Hertog Martinus Den
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:10
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
NL58220C
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-11-30 | 1952-05-31 | 1952-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-11-30 | 1956-05-31 | 1956-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-11-30 | 1960-05-31 | 1960-11-30 | $7700.00 | Window Closed / Lapsed |