US2657907A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Insert for drilling strings
Assignee: Individual
•
Filing: 1950-07-24
•
Granted: 1953-11-03
•
Expires: 1970-07-24
Abstract
No abstract record available.
Inventors
- 👤 John F Cochran
- 👤 Jonathan I Middleton
- 👤 Norman D Jaques
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:50
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1078
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) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |