US2552548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Facsimile enciphering system
Assignee: Individual
•
Filing: 1943-03-06
•
Granted: 1951-05-15
•
Expires: 1963-03-06
Abstract
No abstract record available.
Inventors
- 👤 William F Friedman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:13
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/44; H04N1/448
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1310719A
Cited
US1312574A
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US1848839A
Cited
US1657366A
Cited
US1868967A
Cited
US1763358A
Cited
US2300664A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-14 | 1954-11-13 | 1955-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-14 | 1958-11-13 | 1959-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-14 | 1962-11-13 | 1963-05-15 | $7700.00 | Window Closed / Lapsed |