US3113853A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air check valves
Assignee: Regina Corp
•
Filing: 1961-02-16
•
Granted: 1963-12-10
•
Expires: 1981-02-16
Abstract
No abstract record available.
Inventors
- 👤 Edward L Verhagen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:35
CPC Classifications
A; A47; A47L; A47L9/00; A47L9/0072
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) | 1966-12-09 | 1967-06-10 | 1967-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-12-09 | 1971-06-10 | 1971-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-12-09 | 1975-06-10 | 1975-12-10 | $7700.00 | Window Closed / Lapsed |