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US2277623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone system
Assignee: AT&T Inc
•
Filing: 1939-10-12
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Granted: 1942-03-24
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Expires: 1959-10-12
Abstract
No abstract record available.
Inventors
- 👤 Lawrence H Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:14
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/71; H04M1/715
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-03-23 | 1945-09-22 | 1946-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-03-23 | 1949-09-22 | 1950-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-03-23 | 1953-09-22 | 1954-03-24 | $7700.00 | Window Closed / Lapsed |