US4592087B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Class D hearing aid amplifier
Assignee: Knowles Electronics LLC
•
Filing: 1983-12-08
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Granted: 1996-08-13
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Expires: 2003-12-08
Abstract
No abstract record available.
Inventors
- 👤 Mead C Killion
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:58
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/20; H03F3/21; H03F3/217; H03F3/2171; H03K; H03K3/00; H03K3/02; H03K3/353; H03K3/354; H04; H04R; H04R25/00; H04R25/50; H04R25/505
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) | 1999-08-13 | 2000-02-12 | 2000-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-08-13 | 2004-02-12 | 2004-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-08-13 | 2008-02-12 | 2008-08-13 | $7700.00 | Window Closed / Lapsed |