US2789370A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational workbook
Assignee: Individual
•
Filing: 1954-06-28
•
Granted: 1957-04-23
•
Expires: 1974-06-28
Abstract
No abstract record available.
Inventors
- 👤 John W Studebaker
- 👤 John G Studebaker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:54
CPC Classifications
G; G09; G09B; G09B3/00; G09B3/02; G09B3/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1163184A
Cited
US1500777A
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US1617657A
Cited
US1781047A
Cited
US2137447A
Cited
US2213225A
Cited
US2503130A
Cited
US2497200A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-04-22 | 1960-10-22 | 1961-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-04-22 | 1964-10-22 | 1965-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-04-22 | 1968-10-22 | 1969-04-23 | $7700.00 | Window Closed / Lapsed |