US3013464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical level
Assignee: Keuffel and Esser Co
•
Filing: 1955-05-05
•
Granted: 1961-12-19
•
Expires: 1975-05-05
Abstract
No abstract record available.
Inventors
- 👤 Carl W Keuffel
- 👤 Allister L Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:20
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/64; G02B27/646; G02B27/648
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB369130A
Cited
US1533941A
Cited
US2313204A
Cited
US2533686A
Cited
US2557340A
Cited
US2679181A
Cited
US2890616A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-12-18 | 1965-06-19 | 1965-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-12-18 | 1969-06-19 | 1969-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-12-18 | 1973-06-19 | 1973-12-19 | $7700.00 | Window Closed / Lapsed |