US2131089A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Activating and maintaining the activity of dehydrogenation catalysts
Assignee: Shell Development Co
•
Filing: 1935-12-09
•
Granted: 1938-09-27
•
Expires: 1955-12-09
Abstract
No abstract record available.
Inventors
- 👤 Beeck Otto
- 👤 Burgin James
- 👤 Herbert P A Groll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:26
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/32; C07C5/327; C07C5/333; C07C5/3332; B; B01; B01J; B01J37/00; C07C5/321; C07C5/322; C07C5/367; Y; Y10; Y10S; Y10S252/00; Y10S252/18; 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) | 1941-09-26 | 1942-03-28 | 1942-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-09-26 | 1946-03-28 | 1946-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-09-26 | 1950-03-28 | 1950-09-27 | $7700.00 | Window Closed / Lapsed |