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US2813458A
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Assignee: Farrand Optical Co Inc
•
Filing: 1952-09-18
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Granted: 1957-11-19
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Expires: 1972-09-18
Abstract
No abstract record available.
Inventors
- 👤 Robert W Tripp
- 👤 Cox Arthur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:09
CPC Classifications
G; G02; G02B; G02B25/00; G02B25/002; G02B25/007
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2151631A
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US2156911A
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US2593724A
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US2352644A
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US2442396A
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US2482115A
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US2490747A
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US2601175A
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US2661658A
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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) | 1960-11-18 | 1961-05-20 | 1961-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-18 | 1965-05-20 | 1965-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-18 | 1969-05-20 | 1969-11-19 | $7700.00 | Window Closed / Lapsed |