Average Co-Inventor Count = 2.67
ph-index = 1
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. (2 from 42,517 patents)
2 patents:
1. 8270816 - Information recording and/or playback apparatus
2. 7885515 - Recording/reproducing device and recording/reproduction method