Average Co-Inventor Count = 3.43
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. Ferno-washington, Inc. (2 from 151 patents)
2 patents:
1. 7520347 - Stair chair with an adjustable glide track resistance and braking device
2. D519064 - Stair chair