Patent US2293869A successfully refreshed from Google Patents.
US2293869A
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Signaling system
Assignee: AT&T Inc
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Filing: 1940-09-14
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Granted: 1942-08-25
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Expires: 1960-09-14
Abstract
No abstract record available.
Inventors
- 👤 Henry E Vaughan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:25
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/446; H04Q1/4465
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) | 1945-08-24 | 1946-02-23 | 1946-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-08-24 | 1950-02-23 | 1950-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-08-24 | 1954-02-23 | 1954-08-25 | $7700.00 | Window Closed / Lapsed |