Average Co-Inventor Count = 1.29
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. Hydril Company (1 from 277 patents)
2. Stewart & Stevenson Oiltools, Inc. (1 from 2 patents)
3. C. Jim Stewart & Stevenson, Inc. (1 from 1 patent)
3 patents:
1. 4619111 - Oilfield closing device operating system
2. 3993100 - Hydraulic control system for controlling a plurality of underwater
3. 3957079 - Valve assembly for a subsea well control system