US2635355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational enumeration block assembly
Assignee: Individual
•
Filing: 1951-01-08
•
Granted: 1953-04-21
•
Expires: 1971-01-08
Abstract
No abstract record available.
Inventors
- 👤 Howard G Thompson
- 👤 Helen L Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:46
CPC Classifications
G; G09; G09B; G09B19/00; G09B19/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2494497A
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US2492922A
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US2514636A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-04-20 | 1956-10-20 | 1957-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-20 | 1960-10-20 | 1961-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-20 | 1964-10-20 | 1965-04-21 | $7700.00 | Window Closed / Lapsed |