Average Co-Inventor Count = 2.80
ph-index = 2
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 (5 from 5,452 patents)
5 patents:
1. 8178251 - Fuel cell system
2. 7700868 - Musical instrument and supporting system incorporated therein for music players
3. 7692078 - Key actuating apparatus and key actuation control system
4. 7667116 - Key actuating system
5. 7416773 - Sound absorbing body