US1819923A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical process and apparatus for the determination of the nature of the geological formations traversed by drill holes
Assignee: Services Petroliers Schlumberger SA
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Filing: 1929-06-06
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Granted: 1931-08-18
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Expires: 1949-06-06
Abstract
No abstract record available.
Inventors
- 👤 Schlumberger Conrad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:02
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/20; G01V3/22
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) | 1934-08-17 | 1935-02-16 | 1935-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-08-17 | 1939-02-16 | 1939-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-08-17 | 1943-02-16 | 1943-08-18 | $7700.00 | Window Closed / Lapsed |