Jim Simons acquired 525k Amphastar Pharmaceuticals shares worth $14.7M. That's 0.02% of their equity portfolio (799th largest holding). The investor owns 1.25% of the outstanding Amphastar Pharmaceuticals stock. The first Amphastar Pharmaceuticals trade was made in Q1 2015. Since then Jim Simons bought shares 25 more times and sold shares on fifteen occasions. The stake costed the investor $14M, netting the investor a gain of 4.9% so far.