US1781469A
Expired / Lapsed
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Assignee: AT&T Inc
•
Filing: 1927-06-25
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Granted: 1930-11-11
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Expires: 1947-06-25
Abstract
No abstract record available.
Inventors
- 👤 Warren P Mason
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:27
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/48; H03H9/50
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) | 1933-11-10 | 1934-05-12 | 1934-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-11-10 | 1938-05-12 | 1938-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-11-10 | 1942-05-12 | 1942-11-11 | $7700.00 | Window Closed / Lapsed |