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US2882997A
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Assignee: Pittsburgh Coke and Chemical Co
•
Filing: 1954-04-26
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Granted: 1959-04-21
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Expires: 1974-04-26
Abstract
No abstract record available.
Inventors
- 👤 Stanton B Smith
- 👤 Arvo J Juhola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:55
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2082; B01D39/2089; B01D39/2003; B01D39/2017; B01D39/2024
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB482137A
Cited
US2614655A
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US2507827A
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US2587234A
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US2708982A
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US2521985A
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US2688380A
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US2765515A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-04-20 | 1962-10-20 | 1963-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-20 | 1966-10-20 | 1967-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-20 | 1970-10-20 | 1971-04-21 | $7700.00 | Window Closed / Lapsed |