Patent US3216931A successfully refreshed from Google Patents.
US3216931A
Expired / Lapsed
US
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Method and means for cleaning impurities from water treating agents
Assignee: Individual
•
Filing: 1962-11-08
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Granted: 1965-11-09
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Expires: 1982-11-08
Abstract
No abstract record available.
Inventors
- 👤 George B Dennis
- 👤 George A Resnik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:04
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/58; C02F1/62; C02F1/64; C02F1/645
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) | 1968-11-08 | 1969-05-10 | 1969-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-08 | 1973-05-10 | 1973-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-08 | 1977-05-10 | 1977-11-09 | $7700.00 | Window Closed / Lapsed |