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US2561476A
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Assignee: AT&T Inc
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Filing: 1947-09-29
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Granted: 1951-07-24
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Expires: 1967-09-29
Abstract
No abstract record available.
Inventors
- 👤 Wilmarth Y Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:55
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B5/00; G11B5/86; G11B5/865; Y; Y10; Y10S; Y10S101/00; Y10S101/37
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US978480A
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US1706044A
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US1875063A
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US1825551A
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US2080100A
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US2427421A
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US2391912A
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US2359617A
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US2416445A
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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) | 1954-07-23 | 1955-01-22 | 1955-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-23 | 1959-01-22 | 1959-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-23 | 1963-01-22 | 1963-07-24 | $7700.00 | Window Closed / Lapsed |