Mario Gabelli acquired 274k NorthWestern Energy Group shares worth $19.5M. That's 0.18% of their equity portfolio (157th largest holding). The first NorthWestern Energy Group trade was made in Q4 2005. Since then Mario Gabelli bought shares 23 more times and sold shares on 31 occasions. The stake costed the investor $7.08M, netting the investor a gain of 175% so far.