US2633496A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Party-line telephone system
Assignee: STC PLC
•
Filing: 1948-04-05
•
Granted: 1953-03-31
•
Expires: 1968-04-05
Abstract
No abstract record available.
Inventors
- 👤 Howard G Duhamel
- 👤 Edward O Campbell
- 👤 Raymond A Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:52
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0016
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1482618A
Cited
US1450321A
Cited
US1575140A
Cited
US2108140A
Cited
US2339709A
Cited
US2250101A
Cited
US2447494A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-03-30 | 1956-09-29 | 1957-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-03-30 | 1960-09-29 | 1961-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-03-30 | 1964-09-29 | 1965-03-31 | $7700.00 | Window Closed / Lapsed |