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US2798674A
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Assignee: F E Schundler & Co Inc
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Filing: 1953-01-07
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Granted: 1957-07-09
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Expires: 1973-01-07
Abstract
No abstract record available.
Inventors
- 👤 Paul S Denning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:48
CPC Classifications
B; B01; B01D; B01D37/00; B01D37/02; B02; B02C; B02C13/00; B02C13/14; B02C13/18; B02C13/1807; B02C23/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1484208A
Cited
US1608717A
Cited
GB394478A
Cited
US2352327A
Cited
US2474314A
Cited
US2602782A
Cited
US2651470A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-08 | 1961-01-07 | 1961-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-08 | 1965-01-07 | 1965-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-08 | 1969-01-07 | 1969-07-09 | $7700.00 | Window Closed / Lapsed |