US2950087A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined rotary and percussion drilling
Assignee: Individual
•
Filing: 1955-10-24
•
Granted: 1960-08-23
•
Expires: 1975-10-24
Abstract
No abstract record available.
Inventors
- 👤 James N Gregory
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:50
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/64; E21B6/00; E21B7/00; E21B7/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1567197A
Cited
US2054255A
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US2085279A
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US2120240A
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US2170716A
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US2567451A
Cited
US2554005A
Cited
US2708103A
Cited
US2710740A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-08-23 | 1964-02-22 | 1964-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-08-23 | 1968-02-22 | 1968-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-08-23 | 1972-02-22 | 1972-08-23 | $7700.00 | Window Closed / Lapsed |