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US2290774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil well swab
Assignee: Individual
•
Filing: 1940-09-09
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Granted: 1942-07-21
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Expires: 1960-09-09
Abstract
No abstract record available.
Inventors
- 👤 Raymond W Skinner
- 👤 Percival B Skinner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:19
CPC Classifications
E; E21; E21B; E21B37/00; E21B37/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-07-20 | 1946-01-19 | 1946-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-07-20 | 1950-01-19 | 1950-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-07-20 | 1954-01-19 | 1954-07-21 | $7700.00 | Window Closed / Lapsed |