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US2869644A
Expired / Lapsed
US
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Washover tool for use in wells
Assignee: Individual
•
Filing: 1955-05-31
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Granted: 1959-01-20
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Expires: 1975-05-31
Abstract
No abstract record available.
Inventors
- 👤 Cicero C Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:51
CPC Classifications
E; E21; E21B; E21B31/00; E21B31/12; E21B31/18
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2449841A
Cited
US2577605A
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US2647008A
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US2804151A
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US2762438A
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US2771957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-01-19 | 1962-07-21 | 1963-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-01-19 | 1966-07-21 | 1967-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-01-19 | 1970-07-21 | 1971-01-20 | $7700.00 | Window Closed / Lapsed |