US3500923A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Use of highly saline ethoxylated surfactant system for oil recovery
Assignee: Shell USA Inc
•
Filing: 1968-08-08
•
Granted: 1970-03-17
•
Expires: 1988-08-08
Abstract
No abstract record available.
Inventors
- 👤 Joseph Reisberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:29
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2827964A
Cited
US3330344A
Cited
US3373107A
Cited
US3318379A
Cited
US3326287A
Cited
US3333634A
Cited
US3373809A
Cited
US3347789A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |