Patent US2500565A successfully refreshed from Google Patents.
US2500565A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Educational device
Assignee: Individual
•
Filing: 1945-07-21
•
Granted: 1950-03-14
•
Expires: 1965-07-21
Abstract
No abstract record available.
Inventors
- 👤 Ollie W Phillips
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:25
CPC Classifications
G; G09; G09B; G09B25/00; G09B25/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US687570A
Cited
US727140A
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US799609A
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US1671938A
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US1954561A
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US2058265A
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US2269035A
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US2346225A
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US2338850A
Cited
US2394282A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-03-13 | 1953-09-12 | 1954-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-03-13 | 1957-09-12 | 1958-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-03-13 | 1961-09-12 | 1962-03-14 | $7700.00 | Window Closed / Lapsed |