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Patent US2951893A successfully refreshed from Google Patents.
US2951893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Teletypewriter switching system
Assignee: AT&T Inc
•
Filing: 1953-11-25
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Granted: 1960-09-06
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Expires: 1973-11-25
Abstract
No abstract record available.
Inventors
- 👤 Joseph A Krecek
- 👤 George A Locke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:47
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/54
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-09-06 | 1964-03-07 | 1964-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-09-06 | 1968-03-07 | 1968-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-09-06 | 1972-03-07 | 1972-09-06 | $7700.00 | Window Closed / Lapsed |