US3426508A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter unit for air systems
Assignee: Individual
•
Filing: 1967-08-09
•
Granted: 1969-02-11
•
Expires: 1987-08-09
Abstract
No abstract record available.
Inventors
- 👤 Doyle Wayne Mcgrath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:26
CPC Classifications
B; B01; B01D; B01D46/00; Y; Y10; Y10T; Y10T137/00; Y10T137/2931; Y10T137/3003; Y10T137/3102; Y10T137/3105
Claims Analysis
Total Claims: 0
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US2962119A
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US3054552A
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US3093467A
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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) | 1972-02-11 | 1972-08-12 | 1973-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-11 | 1976-08-12 | 1977-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-11 | 1980-08-12 | 1981-02-11 | $7700.00 | Window Closed / Lapsed |