Patent US2677726A successfully refreshed from Google Patents.
US2677726A
Expired / Lapsed
US
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Signaling system for carrier telephone transmission
Assignee: AT&T Inc
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Filing: 1950-07-26
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Granted: 1954-05-04
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Expires: 1970-07-26
Abstract
No abstract record available.
Inventors
- 👤 Ferdinand S Entz
- 👤 George A Pullis
- 👤 Ralph E Ressler
- 👤 Robert O Soffel
- 👤 Laurance A Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:48
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/442
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-05-03 | 1957-11-02 | 1958-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-05-03 | 1961-11-02 | 1962-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-05-03 | 1965-11-02 | 1966-05-04 | $7700.00 | Window Closed / Lapsed |