Patent US3538474A successfully refreshed from Google Patents.
US3546221A
Expired / Lapsed
US
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Forming thermoplastic articles
Assignee: Shell USA Inc
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Filing: 1969-06-23
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Granted: 1970-12-08
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Expires: 1989-06-23
Abstract
No abstract record available.
Inventors
- 👤 Herbert G Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:47
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/08; B29C51/082; B29C51/085; B29C51/002; B29C51/14; B29C67/00; B29C67/0029; B30; B30B; B30B5/00; B30B5/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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Cited
US2890541A
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US3319295A
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US3184524A
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US3384695A
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US3470291A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-12-07 | 1974-06-08 | 1974-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-12-07 | 1978-06-08 | 1978-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-12-07 | 1982-06-08 | 1982-12-08 | $7700.00 | Window Closed / Lapsed |