US2277512A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalyst
Assignee: Shell Development Co
•
Filing: 1939-08-28
•
Granted: 1942-03-24
•
Expires: 1959-08-28
Abstract
No abstract record available.
Inventors
- 👤 Simo Martin De
- 👤 Mcmillan Frank Matthew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:08
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/06; Y; Y10; Y10S; Y10S585/00; Y10S585/8995; Y10S585/906
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) | 1945-03-23 | 1945-09-22 | 1946-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-03-23 | 1949-09-22 | 1950-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-03-23 | 1953-09-22 | 1954-03-24 | $7700.00 | Window Closed / Lapsed |