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US2491436A
Expired / Lapsed
US
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Drilling mud
Assignee: Sunoco Inc
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Filing: 1947-07-11
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Granted: 1949-12-13
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Expires: 1967-07-11
Abstract
No abstract record available.
Inventors
- 👤 William E Barnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:08
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/20; C09K8/203
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1847864A
Cited
US1999766A
Cited
US2109858A
Cited
US2213039A
Cited
US2331049A
Cited
US2375616A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-12 | 1953-06-13 | 1953-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-12 | 1957-06-13 | 1957-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-12 | 1961-06-13 | 1961-12-13 | $7700.00 | Window Closed / Lapsed |