Patent US2850566A successfully refreshed from Google Patents.
US1812136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Citric acid manufacture
Assignee: Individual
•
Filing: 1929-02-16
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Granted: 1931-06-30
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Expires: 1949-02-16
Abstract
No abstract record available.
Inventors
- 👤 Frank J Cahn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:07
CPC Classifications
C; C12; C12P; C12P7/00; C12P7/40; C12P7/44; C12P7/48
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) | 1934-06-29 | 1934-12-29 | 1935-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-06-29 | 1938-12-29 | 1939-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-06-29 | 1942-12-29 | 1943-06-30 | $7700.00 | Window Closed / Lapsed |