US3416669A
Expired / Lapsed
US
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Assignee: Dorr Oliver Inc
•
Filing: 1967-04-07
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Granted: 1968-12-17
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Expires: 1987-04-07
Abstract
No abstract record available.
Inventors
- 👤 Peter J Hubbard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:15
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/12; B01D29/00; B01D29/11; B01D29/13; B01D29/15; B01D29/50; B01D29/52; B01D29/62; B01D29/66; B01D29/668; B01D29/76; B01D29/86; B01D35/16; B01D37/00; B01D37/04; B01D2201/00; B01D2201/04; B01D2201/043; B01D2201/0446; B01D2201/28; B01D2201/287
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) | 1971-12-17 | 1972-06-17 | 1972-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-12-17 | 1976-06-17 | 1976-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-12-17 | 1980-06-17 | 1980-12-17 | $7700.00 | Window Closed / Lapsed |