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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
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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)

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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) 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

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