US2542302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wellhead construction
Assignee: Individual
•
Filing: 1948-01-07
•
Granted: 1951-02-20
•
Expires: 1968-01-07
Abstract
No abstract record available.
Inventors
- 👤 Ernest L Barker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:24
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/04; E21B33/0422; E21B2200/00; E21B2200/01; Y; Y10; Y10T; Y10T403/00; Y10T403/49; Y10T403/4958
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1546467A
Cited
US2312476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-19 | 1954-08-21 | 1955-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-19 | 1958-08-21 | 1959-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-19 | 1962-08-21 | 1963-02-20 | $7700.00 | Window Closed / Lapsed |