Patent US3439741A successfully refreshed from Google Patents.
US3439741A
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Steam drive oil production process
Assignee: Phillips Petroleum Co
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Filing: 1967-10-09
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Granted: 1969-04-22
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Expires: 1987-10-09
Abstract
No abstract record available.
Inventors
- 👤 Harry W Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:13
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2862558A
Cited
US2927637A
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US3003555A
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US2988142A
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US3221813A
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US3358758A
Cited
US3347313A
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US3369603A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-21 | 1972-10-21 | 1973-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-21 | 1976-10-21 | 1977-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-21 | 1980-10-21 | 1981-04-22 | $7700.00 | Window Closed / Lapsed |