US3520131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas control
Assignee: Individual
•
Filing: 1968-03-04
•
Granted: 1970-07-14
•
Expires: 1988-03-04
Abstract
No abstract record available.
Inventors
- 👤 Southwick W Briggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:59
CPC Classifications
F; F01; F01N; F01N13/00; F01N13/08; F01N13/10; F01N13/18; F01N13/1805; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/30; F01N3/34; F01N2450/00; F01N2450/24; F01N2470/00; F01N2470/30; F02; F02B; F02B2275/00; F02B2275/34; F02B75/00; F02B75/16; F02B75/18; F02B75/20; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE151557C
Cited
US939844A
Cited
GB352912A
Cited
GB386901A
Cited
US2263318A
Cited
US2677231A
Cited
GB739715A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-13 | 1974-01-12 | 1974-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-13 | 1978-01-12 | 1978-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-13 | 1982-01-12 | 1982-07-14 | $7700.00 | Window Closed / Lapsed |