US2242139A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for water purification
Assignee: Individual
•
Filing: 1938-03-25
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Granted: 1941-05-13
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Expires: 1958-03-25
Abstract
No abstract record available.
Inventors
- 👤 Walter C Munroe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:20
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5281; B; B03; B03D; B03D1/00; B03D1/14; B03D1/1431; B03D1/1443; B03D1/1462; B03D1/1475
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1944-05-12 | 1944-11-11 | 1945-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-05-12 | 1948-11-11 | 1949-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-05-12 | 1952-11-11 | 1953-05-13 | $7700.00 | Window Closed / Lapsed |