Average Co-Inventor Count = 1.26
ph-index = 4
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. Nippon Gakki Seizo Kabushiki Kaisha (4 from 841 patents)
2. Yamaha Corporation (2 from 5,454 patents)
6 patents:
1. D597528 - Speaker
2. D595335 - Electronic keyboard instrument
3. D310679 - Electronic wind instrument
4. 4742749 - Lid structure of electronic musical instrument
5. D265832 - Electric organ
6. D258214 - Synthesizer organ, or the like