US2725216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling bit
Assignee: Individual
•
Filing: 1951-07-20
•
Granted: 1955-11-29
•
Expires: 1971-07-20
Abstract
No abstract record available.
Inventors
- 👤 Philip B Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:10
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/56; E21B10/36
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US54982A
Cited
US829633A
Cited
US875664A
Cited
US955877A
Cited
US1388490A
Cited
US1506119A
Cited
US1524776A
Cited
US1891222A
Cited
US2090058A
Cited
US2358052A
Cited
US2435916A
Cited
US2582944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-11-28 | 1959-05-30 | 1959-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-11-28 | 1963-05-30 | 1963-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-11-28 | 1967-05-30 | 1967-11-29 | $7700.00 | Window Closed / Lapsed |