US3493494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sludge treatment apparatus and method
Assignee: Simon Hartley Ltd
•
Filing: 1968-02-05
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Granted: 1970-02-03
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Expires: 1988-02-05
Abstract
No abstract record available.
Inventors
- 👤 Roger G Knibb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:22
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/28; B; B01; B01F; B01F25/00; B01F25/50; B01F25/53; B01F23/00; B01F23/20; B01F23/23; B01F23/232; B01F23/2323; B01F23/23231; B01F23/232311; B01F25/20; B01F25/21
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US3078999A
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GB911164A
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US3187897A
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US3288295A
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US3152982A
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US3220706A
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US3279606A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-02-02 | 1973-08-04 | 1974-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-02 | 1977-08-04 | 1978-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-02 | 1981-08-04 | 1982-02-03 | $7700.00 | Window Closed / Lapsed |