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US2560328A
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Assignee: Standard Oil Development Co
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Filing: 1949-06-15
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Granted: 1951-07-10
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Expires: 1969-06-15
Abstract
No abstract record available.
Inventors
- 👤 Walter J Bielstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:10
CPC Classifications
E; E21; E21B; E21B12/00; E21B12/02
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) | 1954-07-09 | 1955-01-08 | 1955-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-09 | 1959-01-08 | 1959-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-09 | 1963-01-08 | 1963-07-10 | $7700.00 | Window Closed / Lapsed |