US1789477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnet core
Assignee: Associated Telephone and Telegraph Co
•
Filing: 1929-04-27
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Granted: 1931-01-20
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Expires: 1949-04-27
Abstract
No abstract record available.
Inventors
- 👤 Roseby Philip Norton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:49
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; H01F1/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1934-01-19 | 1934-07-21 | 1935-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-01-19 | 1938-07-21 | 1939-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-01-19 | 1942-07-21 | 1943-01-20 | $7700.00 | Window Closed / Lapsed |