Average Co-Inventor Count = 3.00
ph-index = 3
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 (3 from 5,451 patents)
3 patents:
1. 5890910 - Method of managing information files in a communication karaoke
2. 5833469 - Method of operating a karaoke network system with system program
3. 5824934 - Karaoke system including host apparatus that downloads information file