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US2643578A
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Assignee: Individual
•
Filing: 1951-06-19
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Granted: 1953-06-30
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Expires: 1971-06-19
Abstract
No abstract record available.
Inventors
- 👤 Williams John Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:24
CPC Classifications
G; G02; G02B; G02B30/00; G02B30/20; G02B30/34; G02B30/37
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE371274C
Cited
FR668950A
Cited
FR675940A
Cited
US1956938A
Cited
US2071120A
Cited
US2122649A
Cited
DE710240C
Cited
US2368480A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-29 | 1956-12-29 | 1957-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-29 | 1960-12-29 | 1961-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-29 | 1964-12-29 | 1965-06-30 | $7700.00 | Window Closed / Lapsed |