Patent US3540838A successfully refreshed from Google Patents.
US3540838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating exhaust gases of internal combustion engines
Assignee: Catalysts and Chemicals Inc
•
Filing: 1968-07-03
•
Granted: 1970-11-17
•
Expires: 1988-07-03
Abstract
No abstract record available.
Inventors
- 👤 Ronald E Reitmeier
- 👤 Daniel A Hirschler Jr
- 👤 Frances W Lamb
- 👤 Ruth E Stephens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:22
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/944; B01J; B01J23/00; B01J23/70; B01J23/89; B01J23/8926
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3374183A
Cited
US3310366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-16 | 1974-05-18 | 1974-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-16 | 1978-05-18 | 1978-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-16 | 1982-05-18 | 1982-11-17 | $7700.00 | Window Closed / Lapsed |