US2651513A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of mining and handling coal
Assignee: Individual
•
Filing: 1951-02-05
•
Granted: 1953-09-08
•
Expires: 1971-02-05
Abstract
No abstract record available.
Inventors
- 👤 Ramsay Erskine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:10
CPC Classifications
E; E21; E21C; E21C41/00; E21C41/16; E21C41/18
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1632800A
Cited
US2283212A
Cited
US2155415A
Cited
US2330437A
Cited
US2358687A
Cited
US2407448A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-09-07 | 1957-03-09 | 1957-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-09-07 | 1961-03-09 | 1961-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-09-07 | 1965-03-09 | 1965-09-08 | $7700.00 | Window Closed / Lapsed |