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US1421341A
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Assignee: Individual
•
Filing: 1919-07-23
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Granted: 1922-06-27
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Expires: 1939-07-23
Abstract
No abstract record available.
Inventors
- 👤 Zsigmondy Richard
- 👤 Bachmann Wilhelm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:28
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/08; B01D71/12; B01D71/14
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) | 1925-06-26 | 1925-12-26 | 1926-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1929-06-26 | 1929-12-26 | 1930-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1933-06-26 | 1933-12-26 | 1934-06-27 | $7700.00 | Window Closed / Lapsed |