US2354922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable derrick
Assignee: INT STACEY CORP
•
Filing: 1941-12-05
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Granted: 1944-08-01
•
Expires: 1961-12-05
Abstract
No abstract record available.
Inventors
- 👤 Mcewen John
- 👤 John P Selberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:32
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/02; E21B7/023
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) | 1947-08-01 | 1948-01-31 | 1948-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1951-08-01 | 1952-01-31 | 1952-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1955-08-01 | 1956-01-31 | 1956-08-01 | $7700.00 | Window Closed / Lapsed |