Average Co-Inventor Count = 7.24
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. (5 from 42,496 patents)
2. Hitachi Chemical Company, Ltd. (3 from 1,641 patents)
5 patents:
1. 4623415 - Method of making fuel cell
2. 4529671 - Fuel cell
3. 4493879 - Fuel cell
4. 4446210 - Fuel cell electrode
5. 4407905 - Fuel cell