US2776819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rock drill bit
Assignee: Individual
•
Filing: 1953-10-09
•
Granted: 1957-01-08
•
Expires: 1973-10-09
Abstract
No abstract record available.
Inventors
- 👤 Philip B Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:31
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/36
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) | 1960-01-08 | 1960-07-09 | 1961-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-08 | 1964-07-09 | 1965-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-08 | 1968-07-09 | 1969-01-08 | $7700.00 | Window Closed / Lapsed |