Average Co-Inventor Count = 2.40
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. Okamura Corporation (2 from 421 patents)
2 patents:
1. 8251454 - Backrest of the chair and adaptation device for the same
2. 8191970 - Backrest device in a chair