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US3538431A
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Geophysical prospecting with subsurface propagated electromagnetic waves
Assignee: American Smelting and Refining Co
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Filing: 1968-09-26
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Granted: 1970-11-03
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Expires: 1988-09-26
Abstract
No abstract record available.
Inventors
- 👤 Calvin K Moss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:23
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3123767A
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US1676779A
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US1792910A
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US2268106A
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US2653220A
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US2992325A
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US3036265A
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US3065408A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-02 | 1974-05-04 | 1974-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-02 | 1978-05-04 | 1978-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-02 | 1982-05-04 | 1982-11-03 | $7700.00 | Window Closed / Lapsed |