Average Co-Inventor Count = 1.67
ph-index = 5
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. Sony Corporation (5 from 58,130 patents)
5 patents:
1. D333917 - Earphone case
2. D323167 - Headphone
3. D318864 - Earphone
4. D316861 - Headphone
5. D314574 - Combined tape player and earphone