US2849212A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling apparatus
Assignee: Individual
•
Filing: 1956-12-10
•
Granted: 1958-08-26
•
Expires: 1976-12-10
Abstract
No abstract record available.
Inventors
- 👤 Robbins Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:56
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US417352A
Cited
US2029223A
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US2088649A
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US2215928A
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US2594098A
Cited
US2480537A
Cited
US2712921A
Cited
US2665116A
Cited
US2781185A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-08-25 | 1962-02-24 | 1962-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-25 | 1966-02-24 | 1966-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-25 | 1970-02-24 | 1970-08-26 | $7700.00 | Window Closed / Lapsed |