Average Co-Inventor Count = 7.47
ph-index = 2
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. Other (1 from 832,891 patents)
2. Hitachi, Ltd. (1 from 42,508 patents)
2 patents:
1. 6202158 - Detection method of illegal access to computer system
2. 6173418 - Computer for gathering log data