Patent US2421331A successfully refreshed from Google Patents.
US2421331A
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US
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Production of alkylaromatics
Assignee: Standard Oil Co
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Filing: 1944-02-29
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Granted: 1947-05-27
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Expires: 1964-02-29
Abstract
No abstract record available.
Inventors
- 👤 Everett A Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:58
CPC Classifications
C; C07; C07C; C07C15/00; C07C15/02; C10; C10G; C10G2400/00; C10G2400/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1953702A
Cited
US2010948A
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US2010949A
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US2238594A
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US2222632A
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US2335596A
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US2290211A
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US2338711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-26 | 1950-11-25 | 1951-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-26 | 1954-11-25 | 1955-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-26 | 1958-11-25 | 1959-05-27 | $7700.00 | Window Closed / Lapsed |