US2958336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Back pressure valve
Assignee: FMC Corp
•
Filing: 1958-04-23
•
Granted: 1960-11-01
•
Expires: 1978-04-23
Abstract
No abstract record available.
Inventors
- 👤 John R Yancey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:09
CPC Classifications
E; E21; E21B; E21B34/00; E21B34/02; F; F16; F16K; F16K15/00; F16K15/02; F16K15/04; F16K15/044; Y; Y10; Y10T; Y10T137/00; Y10T137/7504; Y10T137/8593; Y10T137/877; Y10T137/87829; Y10T137/87837; Y10T137/87845
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1880778A
Cited
US2379079A
Cited
US2358677A
Cited
US2707480A
Cited
US2751014A
Cited
US2778433A
Cited
US2830666A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-11-01 | 1964-05-02 | 1964-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-11-01 | 1968-05-02 | 1968-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-11-01 | 1972-05-02 | 1972-11-01 | $7700.00 | Window Closed / Lapsed |