US2939093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Directional channel separation filters
Assignee: Individual
•
Filing: 1956-06-26
•
Granted: 1960-05-31
•
Expires: 1976-06-26
Abstract
No abstract record available.
Inventors
- 👤 Pierre G Marie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:50
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/213; H01P1/2138
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2723377A
Cited
US2283935A
Cited
US2584399A
Cited
US2626990A
Cited
US2806210A
Cited
US2851681A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-05-31 | 1963-11-30 | 1964-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-05-31 | 1967-11-30 | 1968-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-05-31 | 1971-11-30 | 1972-05-31 | $7700.00 | Window Closed / Lapsed |