Patents in grey text have expired
HIMPP NEC-01: Title: Hearing aid system using directivity microphone array
JP3045149
HIMPP NEC-02: Title: Digital hearing aid
US6023517
Patent family: JP3165044
HIMPP NEC-03: Title: Digital hearing aid
US5838801
Patent family: JP2904272
HIMPP NEC-04: Title: Digital hearing aid and its hearing sense compensation processing method
US6094489
Patent family: JP2953397
HIMPP NEC-05: Title: Digital hearing aid
US5892836
Patent family: JP2970498
HIMPP NEC-06: Title: Digitally programmable hearing aid communicable with external apparatus through acoustic signal
US5910997
Patent family: JP2763022
HIMPP NEC-07: Title: History holding type hearing aid
JP 2638563
HIMPP NEC-08: Title: Hearing aid system
US5835610
Patent family: JP2982672
HIMPP NEC-09: Title: Hearing aid for controlling hearing sense compensation with suitable parameters internally tailored
US5852668
HIMPP NEC-10: Title: Hearing aid
US6330339