US1881711A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic structure
Assignee: AT&T Inc
•
Filing: 1931-08-14
•
Granted: 1932-10-11
•
Expires: 1951-08-14
Abstract
No abstract record available.
Inventors
- 👤 Lathrop Hubbel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:54
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
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1935-10-11 | 1936-04-11 | 1936-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-10-11 | 1940-04-11 | 1940-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-10-11 | 1944-04-11 | 1944-10-11 | $7700.00 | Window Closed / Lapsed |