US2982928A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric filter
Assignee: Individual
•
Filing: 1958-04-29
•
Granted: 1961-05-02
•
Expires: 1978-04-29
Abstract
No abstract record available.
Inventors
- 👤 Albert R Kall
- 👤 Circle John Russell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:08
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/0115; H03H1/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1749841A
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US1836575A
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US1962910A
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US2252609A
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US2313440A
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US2355516A
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FR952403A
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US2738466A
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US2682037A
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GB740465A
Cited
US2844801A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-05-01 | 1964-10-31 | 1965-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-05-01 | 1968-10-31 | 1969-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-05-01 | 1972-10-31 | 1973-05-02 | $7700.00 | Window Closed / Lapsed |