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US3442331A
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US
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Cyclic secondary oil recovery process
Assignee: Central Oil Co
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Filing: 1967-05-22
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Granted: 1969-05-06
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Expires: 1987-05-22
Abstract
No abstract record available.
Inventors
- 👤 Walter B Fulton
- 👤 Leonard J Wickenhauser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:54
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3251412A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-05 | 1972-11-04 | 1973-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-05 | 1976-11-04 | 1977-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-05 | 1980-11-04 | 1981-05-06 | $7700.00 | Window Closed / Lapsed |