US3481722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing hydrogen
Assignee: Engelhard Industries Inc
•
Filing: 1964-05-15
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Granted: 1969-12-02
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Expires: 1984-05-15
Abstract
No abstract record available.
Inventors
- 👤 William C Pfefferle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:25
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/02; C01B3/32; C01B3/34; C01B3/38; C01B3/40; C01B2203/00; C01B2203/10; C01B2203/1041; C01B2203/1047; C01B2203/1052; C01B2203/1064; C01B2203/107; C01B2203/1082; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/584
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2030283A
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US2907647A
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US3180902A
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US3271325A
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US3222132A
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US3334055A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-12-01 | 1973-06-02 | 1973-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-12-01 | 1977-06-02 | 1977-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-12-01 | 1981-06-02 | 1981-12-02 | $7700.00 | Window Closed / Lapsed |