US2822895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Collapsible derricks
Assignee: Individual
•
Filing: 1953-02-13
•
Granted: 1958-02-11
•
Expires: 1973-02-13
Abstract
No abstract record available.
Inventors
- 👤 Henry R Poetker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:18
CPC Classifications
E; E21; E21B; E21B15/00; E04; E04H; E04H12/00; E04H12/34
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1473054A
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US2268796A
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US2335584A
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US2344390A
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US2365370A
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US2429010A
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US2471492A
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US2551286A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-10 | 1961-08-12 | 1962-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-10 | 1965-08-12 | 1966-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-10 | 1969-08-12 | 1970-02-11 | $7700.00 | Window Closed / Lapsed |