US2257293A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of hydrocarbons
Assignee: Henry Dreyfuss Associates LLC
•
Filing: 1938-02-01
•
Granted: 1941-09-30
•
Expires: 1958-02-01
Abstract
No abstract record available.
Inventors
- 👤 Dreyfus Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:06
CPC Classifications
C; C07; C07C; C07C1/00; C07C1/02; C07C1/10; C07C2523/00; C07C2523/70; C07C2523/74; C07C2523/755
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) | 1944-09-29 | 1945-03-31 | 1945-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-09-29 | 1949-03-31 | 1949-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-09-29 | 1953-03-31 | 1953-09-30 | $7700.00 | Window Closed / Lapsed |