Patent US2539405A successfully refreshed from Google Patents.
US2539405A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio guiding system
Assignee: STC PLC
•
Filing: 1945-04-02
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Granted: 1951-01-30
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Expires: 1965-04-02
Abstract
No abstract record available.
Inventors
- 👤 Edmond M Deloraine
- 👤 Gerard J Lehmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:48
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/02; G01S3/14; G01S3/58; G01S3/66; G01S3/68; G01S1/00; G01S1/02; G01S1/68
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2151549A
Cited
US2226860A
Cited
US2279246A
Cited
US2284812A
Cited
US2426979A
Cited
US2408050A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |