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US2740957A
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US
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Assignee: Individual
•
Filing: 1954-01-19
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Granted: 1956-04-03
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Expires: 1974-01-19
Abstract
No abstract record available.
Inventors
- 👤 Alan D Davies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:08
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/22; G02B5/223
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2374408A
Cited
US2589569A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-04-03 | 1959-10-03 | 1960-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-04-03 | 1963-10-03 | 1964-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-04-03 | 1967-10-03 | 1968-04-03 | $7700.00 | Window Closed / Lapsed |