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US3401798A
Expired / Lapsed
US
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Cylindrically stacked and spirally configured semi-permeable membrane laminate apparatus
Assignee: Dorr Oliver Inc
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Filing: 1965-01-04
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Granted: 1968-09-17
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Expires: 1985-01-04
Abstract
No abstract record available.
Inventors
- 👤 Nyrop Per
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:51
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/10; B01D69/107; B01D63/00; B01D63/08; B01D63/082
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3198335A
Cited
US2337579A
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US2958391A
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US3228876A
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US3246764A
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US3245206A
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US3219567A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-09-17 | 1972-03-18 | 1972-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-09-17 | 1976-03-18 | 1976-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-09-17 | 1980-03-18 | 1980-09-17 | $7700.00 | Window Closed / Lapsed |