Average Co-Inventor Count = 4.10
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 (4 from 5,450 patents)
4 patents:
1. 12183312 - Vibration plate and musical instrument
2. 10984760 - Musical instrument and vibrator
3. 10891923 - Vibrator and musical instrument
4. 8022281 - Shell for drum and drum using the same