Patent US6261243B1 successfully refreshed from Google Patents.
US2696973A
Expired / Lapsed
US
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Nonsticking drill bit
Assignee: FRANCIS R BRITTON
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Filing: 1951-02-09
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Granted: 1954-12-14
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Expires: 1971-02-09
Abstract
No abstract record available.
Inventors
- 👤 Eric A Baumgartner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:08
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/58; E21B17/00; E21B17/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US160484A
Cited
US1489849A
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US1650492A
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US1887373A
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US1965491A
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US2097030A
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US2111785A
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US2215948A
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US2341237A
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US2578593A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-12-13 | 1958-06-14 | 1958-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-12-13 | 1962-06-14 | 1962-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-12-13 | 1966-06-14 | 1966-12-14 | $7700.00 | Window Closed / Lapsed |