Patent US2777669A successfully refreshed from Google Patents.
US2777669A
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Marine well drilling apparatus
Assignee: CORNELIUS G WILLIS
•
Filing: 1948-12-27
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Granted: 1957-01-15
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Expires: 1968-12-27
Abstract
No abstract record available.
Inventors
- 👤 Cornelius G Willis
- 👤 David G Willis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:19
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/12; E21B7/132; B; B63; B63B; B63B21/00; B63B21/50
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-15 | 1960-07-16 | 1961-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-15 | 1964-07-16 | 1965-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-15 | 1968-07-16 | 1969-01-15 | $7700.00 | Window Closed / Lapsed |