Patent US2221952A successfully refreshed from Google Patents.
US2221952A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of valuable carbonaceous substances
Assignee: Standard IG Co
•
Filing: 1938-01-08
•
Granted: 1940-11-19
•
Expires: 1958-01-08
Abstract
No abstract record available.
Inventors
- 👤 Pier Mathias
- 👤 Urban Wilhelm
- 👤 Donath Ernst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:10
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/004; C10G49/00; C10G49/005
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1943-11-19 | 1944-05-20 | 1944-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-19 | 1948-05-20 | 1948-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-19 | 1952-05-20 | 1952-11-19 | $7700.00 | Window Closed / Lapsed |