US2980871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical wave filter
Assignee: Sunoco Inc
•
Filing: 1957-08-05
•
Granted: 1961-04-18
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Expires: 1977-08-05
Abstract
No abstract record available.
Inventors
- 👤 William H Cox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:59
CPC Classifications
H; H03; H03H; H03H17/00; H03H17/02; H03H15/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-17 | 1964-10-17 | 1965-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-17 | 1968-10-17 | 1969-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-17 | 1972-10-17 | 1973-04-18 | $7700.00 | Window Closed / Lapsed |