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US1296820A
Expired / Lapsed
US
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Process for the production and purification of ammonia.
Assignee: Wyeth Holdings LLC
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Filing: 1918-11-05
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Granted: 1919-03-11
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Expires: 1938-11-05
Abstract
No abstract record available.
Inventors
- 👤 Walter S Landis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:55
CPC Classifications
C; C01; C01C; C01C1/00; C01C1/02; C01C1/08
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) | 1922-03-10 | 1922-09-09 | 1923-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1926-03-10 | 1926-09-09 | 1927-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1930-03-10 | 1930-09-09 | 1931-03-11 | $7700.00 | Window Closed / Lapsed |