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US3471581A
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Isomerization of cyclic olefinic hydrocarbons
Assignee: Phillips Petroleum Co
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Filing: 1966-12-15
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Granted: 1969-10-07
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Expires: 1986-12-15
Abstract
No abstract record available.
Inventors
- 👤 Perry L Maxfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:57
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/22; C07C5/23; C07C5/25; C07C5/2506; C07C5/2562; C07C5/2593; C07C5/27; C07C5/31
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US3379706A
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US3294854A
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US3250818A
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US3363016A
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US3309410A
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US3361837A
Cited
US3320327A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-06 | 1973-04-07 | 1973-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-06 | 1977-04-07 | 1977-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-06 | 1981-04-07 | 1981-10-07 | $7700.00 | Window Closed / Lapsed |