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Patent US2243340A successfully refreshed from Google Patents.
US2243340A
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Rotary blowout preventer
Assignee: Individual
•
Filing: 1938-05-23
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Granted: 1941-05-27
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Expires: 1958-05-23
Abstract
No abstract record available.
Inventors
- 👤 Frederic W Hild
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:06
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/08; E21B33/085
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) | 1944-05-26 | 1944-11-25 | 1945-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-05-26 | 1948-11-25 | 1949-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-05-26 | 1952-11-25 | 1953-05-27 | $7700.00 | Window Closed / Lapsed |