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US3515213A
Expired / Lapsed
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Shale oil recovery process using heated oil-miscible fluids
Assignee: Shell USA Inc
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Filing: 1967-04-19
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Granted: 1970-06-02
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Expires: 1987-04-19
Abstract
No abstract record available.
Inventors
- 👤 Michael Prats
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:40
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2813583A
Cited
US3136359A
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US3342257A
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US3284281A
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US3358756A
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US3322194A
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US3382922A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-01 | 1973-12-01 | 1974-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-01 | 1977-12-01 | 1978-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-01 | 1981-12-01 | 1982-06-02 | $7700.00 | Window Closed / Lapsed |