Average Co-Inventor Count = 4.71
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. Hitachi, Ltd. (4 from 42,508 patents)
4 patents:
1. D345156 - Video tape recorder
2. D336638 - Portable computer
3. D317302 - Portable computer
4. D310524 - Telephone station set