Average Co-Inventor Count = 1.20
ph-index = 1
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Yamaha Corporation (2 from 5,450 patents)
2. Roki Co., Ltd. (1 from 13 patents)
3 patents:
1. 9683526 - Canister
2. 7604090 - Circuit-unit-combined speaker apparatus
3. 7542576 - Howling detection circuit