Chuck Royce acquired 404k MKS Instruments shares worth $133M. That's 1.16% of their equity portfolio (2nd largest holding). The first MKS Instruments trade was made in Q1 2013. Since then Chuck Royce bought shares nineteen more times and sold shares on 33 occasions. The stake costed the investor $14.4M, netting the investor a gain of 825% so far.