US2519861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double-acting drill bit
Assignee: JOHN D BILBAO
•
Filing: 1947-01-14
•
Granted: 1950-08-22
•
Expires: 1967-01-14
Abstract
No abstract record available.
Inventors
- 👤 Frank G Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:30
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/003; E21B10/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US54199A
Cited
US54526A
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US658060A
Cited
US803911A
Cited
US1859342A
Cited
US2368512A
Cited
US2499282A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-21 | 1954-02-20 | 1954-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-21 | 1958-02-20 | 1958-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-21 | 1962-02-20 | 1962-08-22 | $7700.00 | Window Closed / Lapsed |