Patent US1938872A successfully refreshed from Google Patents.
US1938872A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Orientation recorder for wells
Assignee: Hydril LLC
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Filing: 1929-10-08
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Granted: 1933-12-12
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Expires: 1949-10-08
Abstract
No abstract record available.
Inventors
- 👤 Stone Frederick
- 👤 Albert L Stone
- 👤 Clarence R Dale
- 👤 Lester C Nielson
- 👤 Roy A Silent
- 👤 August R Maier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:51
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/02; E21B47/022; E21B47/0236
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) | 1936-12-11 | 1937-06-12 | 1937-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-12-11 | 1941-06-12 | 1941-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-12-11 | 1945-06-12 | 1945-12-12 | $7700.00 | Window Closed / Lapsed |