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US2879608A
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Assignee: WATKINS STRATHMORE Co
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Filing: 1956-04-10
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Granted: 1959-03-31
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Expires: 1976-04-10
Abstract
No abstract record available.
Inventors
- 👤 Daniel H Watkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:10
CPC Classifications
G; G09; G09B; G09B3/00; G09B3/02; G09B3/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1510110A
Cited
US1617657A
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US1750977A
Cited
US2074855A
Cited
GB512794A
Cited
US2213225A
Cited
US2455353A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-03-30 | 1962-09-29 | 1963-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-30 | 1966-09-29 | 1967-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-30 | 1970-09-29 | 1971-03-31 | $7700.00 | Window Closed / Lapsed |