Image source: Dynegy.

What: Shares of Dynegy (NYSE: DYN), an energy company that operates power-generating facilities in eight states in the Midwest, Northeast, and on the West Coast, are rising Wednesday after insider buying sent a bullish signal to investors.

So what: After what's been a brutal 12 months for the company's stock price, the company's president and chief executive officer, Robert C. Flexon, acquired 10,000 shares Tuesday at price per share of $10.08. That amount increased Flexon's total to more than 436,000 shares.

Furthermore, a couple of institutional investors jumped on board during the fourth quarter, with TFS Capital LLC purchasing 137,532 shares and ClariVest Asset Management LLC adding another 22,600 shares to its pile that now totals 52,000 shares. That was just the latest in multiple insider buys at Dynegy. On Dec. 10, 2015, Director Patrick Wood purchased 6,400 shares at $11.61, and in mid-November Flexon and EVP Daniel Thompson purchased 10,000 shares and 1,000 shares, respectively, at $16.70 and $17.55 per share.

DYN Chart
DYN data by YCharts.

Now what: When insiders and institutional investors continue to buy in groups, like has recently happened at Dynegy, it sends a bullish signal to investors. It's been a brutal past 12 months for the stock price and investors appear to be jumping on board after insider buying and a recent upgrade by analysts at Guggenheim suggest the price has bottomed out.