Average Co-Inventor Count = 1.33
ph-index = 4
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 (6 from 58,130 patents)
6 patents:
1. D381988 - Speaker box
2. D380756 - Combined digital audio disk player, tuner and tape recorder
3. D370912 - Tape player
4. D367756 - Portable carrying grip with belt
5. D360636 - Speaker box
6. D325468 - Optical disc cartridge