US2537897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter element
Assignee: Individual
•
Filing: 1947-07-09
•
Granted: 1951-01-09
•
Expires: 1967-07-09
Abstract
No abstract record available.
Inventors
- 👤 Robert H Hunter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:50
CPC Classifications
B; B01; B01D; B01D27/00; B01D27/04; B01D27/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1565988A
Cited
US2138383A
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US2115577A
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US2218339A
Cited
US2210397A
Cited
US2346903A
Cited
US2339703A
Cited
US2386684A
Cited
US2464870A
Cited
US2427733A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-08 | 1954-07-10 | 1955-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-08 | 1958-07-10 | 1959-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-08 | 1962-07-10 | 1963-01-09 | $7700.00 | Window Closed / Lapsed |