US2365639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil well filter
Assignee: EIDP Inc
•
Filing: 1941-12-06
•
Granted: 1944-12-19
•
Expires: 1961-12-06
Abstract
No abstract record available.
Inventors
- 👤 Holmes Harrison Howard
- 👤 Lawson Walter Eastby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:31
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/02; E21B43/08
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) | 1947-12-19 | 1948-06-19 | 1948-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1951-12-19 | 1952-06-19 | 1952-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1955-12-19 | 1956-06-19 | 1956-12-19 | $7700.00 | Window Closed / Lapsed |