Average Co-Inventor Count = 2.00
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. Other (2 from 832,718 patents)
2 patents:
1. 4008577 - Cut and cover construction of subway with utility chamber and air
2. 3999394 - Precast ribbed arch subway structure and method