US2461813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentration of phosphate minerals
Assignee: Minerals Separation North American Corp
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Filing: 1945-11-14
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Granted: 1949-02-15
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Expires: 1965-11-14
Abstract
No abstract record available.
Inventors
- 👤 James B Duke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:47
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/02; B03D1/021
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) | 1952-02-15 | 1952-08-16 | 1953-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-02-15 | 1956-08-16 | 1957-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-02-15 | 1960-08-16 | 1961-02-15 | $7700.00 | Window Closed / Lapsed |