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. Other (2 from 832,761 patents)
2. Specialty Manufacturing Company (1 from 17 patents)
3 patents:
1. 4559518 - School bus stop sign and crossing arm apparatus
2. 4339744 - School bus stop sign
3. 4138668 - School bus stop sign