US1762984A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Secret-communicating system
Assignee: AT&T Inc
•
Filing: 1928-10-08
•
Granted: 1930-06-10
•
Expires: 1948-10-08
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Heising
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:08
CPC Classifications
H; H04; H04K; H04K1/00; H04K1/04
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) | 1933-06-09 | 1933-12-09 | 1934-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-06-09 | 1937-12-09 | 1938-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-06-09 | 1941-12-09 | 1942-06-10 | $7700.00 | Window Closed / Lapsed |