Average Co-Inventor Count = 2.00
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. Matsushita Electric Industrial Co., Ltd. (3 from 27,375 patents)
3 patents:
1. 4058688 - Headphone
2. D246259 - Head phone
3. 3984885 - 4-Channel headphones