US2621023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System of drilling
Assignee: Individual
•
Filing: 1947-07-11
•
Granted: 1952-12-09
•
Expires: 1967-07-11
Abstract
No abstract record available.
Inventors
- 👤 Click Bernard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:20
CPC Classifications
E; E21; E21B; E21B4/00; E21B4/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1315422A
Cited
US1147898A
Cited
US1370677A
Cited
US1764377A
Cited
US1604200A
Cited
US1773915A
Cited
US2449012A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-09 | 1956-06-09 | 1956-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-09 | 1960-06-09 | 1960-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-09 | 1964-06-09 | 1964-12-09 | $7700.00 | Window Closed / Lapsed |