US2021690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for treating exhaust gases
Assignee: Individual
•
Filing: 1933-09-11
•
Granted: 1935-11-19
•
Expires: 1953-09-11
Abstract
No abstract record available.
Inventors
- 👤 Joseph S Kaufman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:06
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/28; F01N13/00; F01N13/009; F01N2240/00; F01N2240/22; F01N2470/00; F01N2470/02; F01N3/02; Y; Y10; Y10S; Y10S55/00; Y10S55/30
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) | 1938-11-18 | 1939-05-20 | 1939-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-11-18 | 1943-05-20 | 1943-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-11-18 | 1947-05-20 | 1947-11-19 | $7700.00 | Window Closed / Lapsed |