US2499412A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filtering method and apparatus
Assignee: Peterson Filters and Engineering Co
•
Filing: 1943-10-04
•
Granted: 1950-03-07
•
Expires: 1963-10-04
Abstract
No abstract record available.
Inventors
- 👤 Peterson C Lynn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:00
CPC Classifications
B; B01; B01D; B01D33/00; B01D33/06; B01D33/073; B01D33/09; B01D33/44; B01D33/46; B01D33/463
Claims Analysis
Total Claims: 0
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Cited
US2263888A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-03-06 | 1953-09-05 | 1954-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-03-06 | 1957-09-05 | 1958-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-03-06 | 1961-09-05 | 1962-03-07 | $7700.00 | Window Closed / Lapsed |