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US2838731A
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US
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Electrical well logging
Assignee: Phillips Petroleum Co
•
Filing: 1953-07-31
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Granted: 1958-06-10
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Expires: 1973-07-31
Abstract
No abstract record available.
Inventors
- 👤 Charles G Cruzan
- 👤 Raymond G Piety
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:08
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/20; G01V3/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2117390A
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US2133786A
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US2268137A
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US2404622A
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US2393009A
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US2730672A
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US2654064A
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US2655632A
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US2779912A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-09 | 1961-12-09 | 1962-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-09 | 1965-12-09 | 1966-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-09 | 1969-12-09 | 1970-06-10 | $7700.00 | Window Closed / Lapsed |