Average Co-Inventor Count = 4.80
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 5,451 patents)
2 patents:
1. 12367855 - Stringed musical instrument and acoustic effect device
2. 12293747 - Musical instrument