Average Co-Inventor Count = 2.40
ph-index = 6
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 (8 from 5,452 patents)
8 patents:
1. D614686 - Electronic percussion
2. D577056 - Electronic keyboard instrument
3. D569896 - Electronic percussion
4. D566162 - Electronic keyboard instrument
5. D557327 - Electronic keyboard instrument
6. D555714 - Electronic piano
7. D554178 - Electronic keyboard instrument
8. D552157 - Electronic keyboard instrument