US3504448A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational device
Assignee: EARL P MURPHY
•
Filing: 1968-04-05
•
Granted: 1970-04-07
•
Expires: 1988-04-05
Abstract
No abstract record available.
Inventors
- 👤 James T Moore
- 👤 Earl P Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:39
CPC Classifications
G; G09; G09B; G09B7/00; G09B7/06; G09B7/066
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3146534A
Cited
US3327405A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-06 | 1973-10-06 | 1974-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-06 | 1977-10-06 | 1978-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-06 | 1981-10-06 | 1982-04-07 | $7700.00 | Window Closed / Lapsed |