US1669644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic material
Assignee: AT&T Inc
•
Filing: 1926-04-24
•
Granted: 1928-05-15
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Expires: 1946-04-24
Abstract
No abstract record available.
Inventors
- 👤 Andrews John Wendell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:49
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; H01F1/24; H01F1/26; H01F1/147; H01F1/14708; H01F1/14733; H01F1/14741; H01F1/1475; Y; Y10; Y10S; Y10S264/00; Y10S264/58; Y10S29/00; Y10S29/028
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) | 1931-05-15 | 1931-11-14 | 1932-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-05-15 | 1935-11-14 | 1936-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-05-15 | 1939-11-14 | 1940-05-15 | $7700.00 | Window Closed / Lapsed |