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US2456331A
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Core barrel
Assignee: Standard Oil Development Co
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Filing: 1944-05-02
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Granted: 1948-12-14
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Expires: 1964-05-02
Abstract
No abstract record available.
Inventors
- 👤 Benjamin W Sewell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:04
CPC Classifications
E; E21; E21B; E21B49/00; E21B49/02; E21B49/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1998075A
Cited
US2216962A
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US2285024A
Cited
US2347726A
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US2330327A
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US2354399A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-12-14 | 1952-06-14 | 1952-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-14 | 1956-06-14 | 1956-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-14 | 1960-06-14 | 1960-12-14 | $7700.00 | Window Closed / Lapsed |