US2724807A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency-selective systems
Assignee: Individual
•
Filing: 1950-02-16
•
Granted: 1955-11-22
•
Expires: 1970-02-16
Abstract
No abstract record available.
Inventors
- 👤 Harold B Rex
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:59
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1638; H03; H03G; H03G5/00; H03G5/02; H03G5/04; H03G5/06; H03G5/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2395515A
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US2447338A
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US2409610A
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US2480163A
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US2459046A
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US2487675A
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US2552952A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-11-21 | 1959-05-23 | 1959-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-11-21 | 1963-05-23 | 1963-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-11-21 | 1967-05-23 | 1967-11-22 | $7700.00 | Window Closed / Lapsed |