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US221162A
Expired / Lapsed
US
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Improvement in casing-head caps for oil and other wells
Assignee: —
•
Filing: 1879-08-09
•
Granted: 1879-11-04
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Expires: 1899-08-09
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:25
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/04; E21B33/0422; E21B17/00; E21B17/18
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) | 1882-11-03 | 1883-05-05 | 1883-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1886-11-03 | 1887-05-05 | 1887-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1890-11-03 | 1891-05-05 | 1891-11-04 | $7700.00 | Window Closed / Lapsed |