Ken Griffin acquired 404 Thousand NRG Energy shares worth $18.5 Million. That's 0.03% of their equity portfolio (779th largest holding). The first NRG Energy trade was made in Q2 2013. Since then Ken Griffin bought shares 41 more times and sold shares on 37 occasions. The stake costed the investor $11.5 Million, netting the investor a gain of 61% so far.