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Patent US2859654A successfully refreshed from Google Patents.
US2859654A
Expired / Lapsed
US
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Assignee: Individual
•
Filing: 1953-12-02
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Granted: 1958-11-11
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Expires: 1973-12-02
Abstract
No abstract record available.
Inventors
- 👤 Frank G Back
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:30
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/14; G02B15/143; G02B15/1431; G02B15/143105
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-11-10 | 1962-05-12 | 1962-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-11-10 | 1966-05-12 | 1966-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-11-10 | 1970-05-12 | 1970-11-11 | $7700.00 | Window Closed / Lapsed |