US3507330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for secondary recovery of oil
Assignee: Electrothermic Co
•
Filing: 1968-09-30
•
Granted: 1970-04-21
•
Expires: 1988-09-30
Abstract
No abstract record available.
Inventors
- 👤 William G Gill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:07
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/20; E21B43/24; E21B43/2401
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US849524A
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US1372743A
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US1784214A
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US2597261A
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US2795279A
Cited
US2801090A
Cited
US3141504A
Cited
US3137347A
Cited
US3106244A
Cited
US3149672A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-20 | 1973-10-20 | 1974-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-20 | 1977-10-20 | 1978-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-20 | 1981-10-20 | 1982-04-21 | $7700.00 | Window Closed / Lapsed |