Average Co-Inventor Count = 5.06
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. Varco I/p, Inc. (2 from 191 patents)
2. National Oilwell Varco, L.p. (1 from 572 patents)
3 patents:
1. 7748473 - Top drives with shaft multi-seal
2. 7487848 - Multi-seal for top drive shaft
3. 7401664 - Top drive systems