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US2782259A
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Calling subscriber identifier using transistor oscillator in subsets
Assignee: AT&T Inc
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Filing: 1953-12-23
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Granted: 1957-02-19
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Expires: 1973-12-23
Abstract
No abstract record available.
Inventors
- 👤 Thomas L Dimond
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:53
CPC Classifications
H; H04; H04M; H04M15/00; H04M15/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2143563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-02-19 | 1960-08-20 | 1961-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-02-19 | 1964-08-20 | 1965-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-02-19 | 1968-08-20 | 1969-02-19 | $7700.00 | Window Closed / Lapsed |