Patent US2109272A successfully refreshed from Google Patents.
US2109272A
Expired / Lapsed
US
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Selective converting of copper matte
Assignee: Kennecott Corp
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Filing: 1935-05-21
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Granted: 1938-02-22
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Expires: 1955-05-21
Abstract
No abstract record available.
Inventors
- 👤 Larson Leonard
- 👤 John C Kinnear
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:40
CPC Classifications
C; C22; C22B; C22B15/00; C22B15/0026; C22B15/0028; C22B15/005; C22B15/003; C22B15/0041; C22B15/0043
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1941-02-21 | 1941-08-23 | 1942-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-02-21 | 1945-08-23 | 1946-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-02-21 | 1949-08-23 | 1950-02-22 | $7700.00 | Window Closed / Lapsed |