US2690897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combination mill and under-reamer for oil wells
Assignee: Individual
•
Filing: 1950-11-27
•
Granted: 1954-10-05
•
Expires: 1970-11-27
Abstract
No abstract record available.
Inventors
- 👤 Jr Robert E Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:40
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/26; E21B10/32; E21B10/322; E21B29/00; E21B29/002; E21B29/005
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1478306A
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US1752092A
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US1839588A
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US1857616A
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US2108330A
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US2110913A
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US2246711A
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US2324679A
Cited
US2389235A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-10-04 | 1958-04-05 | 1958-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-10-04 | 1962-04-05 | 1962-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-10-04 | 1966-04-05 | 1966-10-05 | $7700.00 | Window Closed / Lapsed |