Average Co-Inventor Count = 1.20
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. Tonka Corporation (3 from 47 patents)
3 patents:
1. 5253866 - Ball with a passive sound device
2. D322105 - Ball
3. 4919422 - Curve ball