US2764465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prevention of oil well casing corrosion
Assignee: Individual
•
Filing: 1953-04-29
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Granted: 1956-09-25
•
Expires: 1973-04-29
Abstract
No abstract record available.
Inventors
- 👤 Gilson H Rohrback
- 👤 Joseph F Chittum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:34
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/03; C09K8/035; E; E21; E21B; E21B41/00; E21B41/02; F; F16; F16L; F16L58/00; F16L58/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-09-25 | 1960-03-26 | 1960-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-09-25 | 1964-03-26 | 1964-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-09-25 | 1968-03-26 | 1968-09-25 | $7700.00 | Window Closed / Lapsed |