PRIMECAP Management's position in Sony . is currently worth $2.35 Billion. That's 1.75% of their equity portfolio (14th largest holding). The investor owns 1.76% of the outstanding Sony . stock. The first Sony . trade was made in Q1 2013. Since then PRIMECAP Management bought shares twelve more times and sold shares on 31 occasions. The stake costed the investor $392 Million, netting the investor a gain of 500% so far.