US2651115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational device
Assignee: Individual
•
Filing: 1950-08-25
•
Granted: 1953-09-08
•
Expires: 1970-08-25
Abstract
No abstract record available.
Inventors
- 👤 Ralph K Davies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:25
CPC Classifications
G; G09; G09B; G09B23/00; G09B23/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US78408A
Cited
US1368608A
Cited
US1880026A
Cited
US1837948A
Cited
US2200060A
Cited
US2477179A
Cited
US2443631A
Cited
US2516418A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-09-07 | 1957-03-09 | 1957-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-09-07 | 1961-03-09 | 1961-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-09-07 | 1965-03-09 | 1965-09-08 | $7700.00 | Window Closed / Lapsed |