US1646377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: SWEETLAND
•
Filing: 1923-11-27
•
Granted: 1927-10-18
•
Expires: 1943-11-27
Abstract
No abstract record available.
Inventors
- 👤 Ernest J Sweetland
- 👤 George H Greenhalgh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:31
CPC Classifications
B; B01; B01D; B01D25/00; B01D25/02; B01D29/00; B01D29/39; B01D35/00; B01D35/14; B01D35/153; B01D2201/00; B01D2201/20; B01D2201/204; B01D2201/208
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) | 1930-10-17 | 1931-04-18 | 1931-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-10-17 | 1935-04-18 | 1935-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-10-17 | 1939-04-18 | 1939-10-18 | $7700.00 | Window Closed / Lapsed |