Average Co-Inventor Count = 2.67
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. Hitachi Kiden Kogyo, Ltd. (2 from 6 patents)
2 patents:
1. 4436026 - Empty can crusher
2. 4090619 - Machine for scraping up grit