Patent US2641754A successfully refreshed from Google Patents.
US2641754A
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Assignee: National Research Development Corp UK
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Filing: 1948-02-26
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Granted: 1953-06-09
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Expires: 1968-02-26
Abstract
No abstract record available.
Inventors
- 👤 Clegg John Ernest
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:17
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/91; G01S13/913
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2522367A
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GB615667A
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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) | 1956-06-08 | 1956-12-08 | 1957-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-08 | 1960-12-08 | 1961-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-08 | 1964-12-08 | 1965-06-09 | $7700.00 | Window Closed / Lapsed |