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Patent US2848543A successfully refreshed from Google Patents.
US2848543A
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US
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Call data recording telephone system
Assignee: AT&T Inc
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Filing: 1954-10-19
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Granted: 1958-08-19
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Expires: 1974-10-19
Abstract
No abstract record available.
Inventors
- 👤 Rolland N Breed
- 👤 Cesareo Orfeo
- 👤 Charles E Germanton
- 👤 Robert W Roberts
- 👤 Laurance A Weber
- 👤 Charles A Wingardner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:23
CPC Classifications
H; H04; H04M; H04M15/00; H04M15/38
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2253998A
Cited
US2341746A
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US2369878A
Cited
US2352492A
Cited
US2531637A
Cited
US2569650A
Cited
US2688658A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-08-18 | 1962-02-17 | 1962-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-18 | 1966-02-17 | 1966-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-18 | 1970-02-17 | 1970-08-19 | $7700.00 | Window Closed / Lapsed |