US2876288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic drum auxiliary sender for telephone switching system
Assignee: AT&T Inc
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Filing: 1955-12-20
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Granted: 1959-03-03
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Expires: 1975-12-20
Abstract
No abstract record available.
Inventors
- 👤 Chester E Brooks
- 👤 William O Fleckenstein
- 👤 Robert C Lee
- 👤 Howard N Seckler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:52
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0004
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) | 1962-03-02 | 1962-09-01 | 1963-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-02 | 1966-09-01 | 1967-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-02 | 1970-09-01 | 1971-03-03 | $7700.00 | Window Closed / Lapsed |