Average Co-Inventor Count = 3.33
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. Hitachi, Ltd. (3 from 42,494 patents)
3 patents:
1. 4525712 - Transaction processing system
2. 4511970 - Portable terminal device
3. 4482802 - Transaction handling system