Patent US2762440A successfully refreshed from Google Patents.
US2762440A
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US
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Apparatus for cementing wells
Assignee: Shell Development Co
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Filing: 1954-05-17
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Granted: 1956-09-11
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Expires: 1974-05-17
Abstract
No abstract record available.
Inventors
- 👤 Davis W Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:07
CPC Classifications
E; E21; E21B; E21B34/00; E21B34/06; E21B34/14; E21B34/142
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-09-11 | 1960-03-12 | 1960-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-09-11 | 1964-03-12 | 1964-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-09-11 | 1968-03-12 | 1968-09-11 | $7700.00 | Window Closed / Lapsed |