US2531919A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio-frequency navigational aid
Assignee: Decca Record Co Ltd
•
Filing: 1947-02-04
•
Granted: 1950-11-28
•
Expires: 1967-02-04
Abstract
No abstract record available.
Inventors
- 👤 William J O'brien
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:21
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02; G01S1/08; G01S1/20; G01S1/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1615712A
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DE546000C
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US2144203A
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US2328944A
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US2405238A
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US2407287A
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US2403600A
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US2403626A
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US2406970A
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US2408773A
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US2419525A
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US2433283A
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US2422386A
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US2428966A
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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) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |