US4444953B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
US4444953B1 - - Google Patents
Assignee: Shell Oil Co
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Filing: 1983-04-18
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Granted: 1987-08-11
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Expires: 2003-04-18
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:05
CPC Classifications
C; C08; C08G; C08G81/00; C08G81/02; C08G81/021; C08G81/022; C08F; C08F297/00; C08F297/02; C08F297/04; C08F297/046
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-10 | 1991-02-09 | 1991-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-10 | 1995-02-09 | 1995-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-10 | 1999-02-09 | 1999-08-11 | $7700.00 | Window Closed / Lapsed |