US2998077A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Subsurface safety shut-off valve apparatus
Assignee: Baker Hughes Oilfield Operations LLC
•
Filing: 1957-12-23
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Granted: 1961-08-29
•
Expires: 1977-12-23
Abstract
No abstract record available.
Inventors
- 👤 Julian D Keithahn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:12
CPC Classifications
E; E21; E21B; E21B34/00; E21B34/06; E21B34/12; E21B2200/00; E21B2200/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2033563A
Cited
US2389985A
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US2785755A
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US2812821A
Cited
US2786535A
Cited
US2798561A
Cited
US2848053A
Cited
US2894715A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-08-28 | 1965-02-27 | 1965-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-08-28 | 1969-02-27 | 1969-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-08-28 | 1973-02-27 | 1973-08-29 | $7700.00 | Window Closed / Lapsed |