Patent US2521697A successfully refreshed from Google Patents.
US2521697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Traffic control system
Assignee: STC PLC
•
Filing: 1944-04-29
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Granted: 1950-09-12
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Expires: 1964-04-29
Abstract
No abstract record available.
Inventors
- 👤 Edmond M Deloraine
- 👤 Paul R Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:59
CPC Classifications
G; G01; G01S; G01S5/00; G01S5/0009; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2163770A
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US2262838A
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US2252083A
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US2407199A
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US2378604A
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US2403603A
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US2344760A
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US2433381A
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US2444452A
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US2421017A
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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) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |