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US1996504A
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Assignee: AT&T Inc
•
Filing: 1933-04-12
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Granted: 1935-04-02
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Expires: 1953-04-12
Abstract
No abstract record available.
Inventors
- 👤 Darlington Sidney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:20
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/54; H03H9/542; H03H9/0023; H03H9/0095
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) | 1938-04-01 | 1938-10-01 | 1939-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-04-01 | 1942-10-01 | 1943-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-04-01 | 1946-10-01 | 1947-04-02 | $7700.00 | Window Closed / Lapsed |