Patent US3541529A successfully refreshed from Google Patents.
US2908330A
Expired / Lapsed
US
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Well tubing extension hanger and plug
Assignee: Otis Engineering Corp
•
Filing: 1954-04-27
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Granted: 1959-10-13
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Expires: 1974-04-27
Abstract
No abstract record available.
Inventors
- 👤 John V Fredd
- 👤 Harry B Schramm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:20
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/02; E21B43/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1670964A
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US1690536A
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US1858215A
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US2189702A
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US2189703A
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US2605843A
Cited
US2636563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-10-12 | 1963-04-13 | 1963-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-10-12 | 1967-04-13 | 1967-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-10-12 | 1971-04-13 | 1971-10-13 | $7700.00 | Window Closed / Lapsed |