Ken Fisher acquired 456 Thousand MKS Instruments shares worth $51.1 Million. That's 0.03% of their equity portfolio (214th largest holding). The first MKS Instruments trade was made in Q1 2013. Since then Ken Fisher bought shares thirteen more times and sold shares on 29 occasions. The stake costed the investor $20.1 Million, netting the investor a gain of 154% so far.