US1809925A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable resistance device
Assignee: AT&T Inc
•
Filing: 1929-05-14
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Granted: 1931-06-16
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Expires: 1949-05-14
Abstract
No abstract record available.
Inventors
- 👤 William H Edwards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:21
CPC Classifications
H; H10; H10W; H10W90/00
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) | 1934-06-15 | 1934-12-15 | 1935-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-06-15 | 1938-12-15 | 1939-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-06-15 | 1942-12-15 | 1943-06-16 | $7700.00 | Window Closed / Lapsed |