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US2238701A
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Method of recovering oil from oil and gas bearing sands
Assignee: MCCOLLUM LAB Inc
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Filing: 1939-01-09
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Granted: 1941-04-15
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Expires: 1959-01-09
Abstract
No abstract record available.
Inventors
- 👤 Mccollum Burton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:00
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/34; E21B43/40
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1944-04-14 | 1944-10-14 | 1945-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-04-14 | 1948-10-14 | 1949-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-04-14 | 1952-10-14 | 1953-04-15 | $7700.00 | Window Closed / Lapsed |