US2226537A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas lift apparatus
Assignee: Shell Development Co
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Filing: 1940-03-08
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Granted: 1940-12-31
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Expires: 1960-03-08
Abstract
No abstract record available.
Inventors
- 👤 Steenbergh Alexander Wilhelmus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:39
CPC Classifications
F; F04; F04F; F04F1/00; F04F1/06; E; E21; E21B; E21B43/00; E21B43/12; E21B43/121
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) | 1943-12-31 | 1944-07-01 | 1944-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-12-31 | 1948-07-01 | 1948-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-12-31 | 1952-07-01 | 1952-12-31 | $7700.00 | Window Closed / Lapsed |