US1852162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refining of copper
Assignee: AT&T Inc
•
Filing: 1929-03-08
•
Granted: 1932-04-05
•
Expires: 1949-03-08
Abstract
No abstract record available.
Inventors
- 👤 James E Harris
- 👤 John H White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:42
CPC Classifications
C; C22; C22B; C22B15/00; C22B15/0026; C22B15/006
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) | 1935-04-05 | 1935-10-05 | 1936-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-04-05 | 1939-10-05 | 1940-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-04-05 | 1943-10-05 | 1944-04-05 | $7700.00 | Window Closed / Lapsed |