US2646816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Backflow prevention device
Assignee: Individual
•
Filing: 1944-10-05
•
Granted: 1953-07-28
•
Expires: 1964-10-05
Abstract
No abstract record available.
Inventors
- 👤 Donald G Griswold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:10
CPC Classifications
E; E03; E03C; E03C1/00; E03C1/02; E03C1/10; E03C1/106; E03C1/108; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2544; Y10T137/2557; Y10T137/2559; Y10T137/2574; Y10T137/2605; Y10T137/263
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1105991A
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US1156447A
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US1606245A
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US1755993A
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US2146204A
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US2310586A
Cited
US2366144A
Cited
US2328118A
Cited
US2372940A
Cited
US2292871A
Cited
US2377227A
Cited
US2389413A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-27 | 1957-01-26 | 1957-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-27 | 1961-01-26 | 1961-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-27 | 1965-01-26 | 1965-07-28 | $7700.00 | Window Closed / Lapsed |