Twitter’s CEO Costolo to Step Down

Major breaking news after the bell: Twitter announced that CEO Dick Costolo is stepping down as top dog at the microblogging giant. He'll be out within the next few weeks. The news comes in the wake of investor dissatisfaction with the leadership of the company, which went public in November of 2013. It was not yet profitable at the time, but the stock soared 73% on its first day of trade. However, after hitting heights of $72 per share just a few months later, the stock then plummeted. The company announced on Thursday afternoon that co-founder Jack Dorsey will serve as interim CEO.

Just as the news spread, Costolo tweeted, "Welcome back, Jack!" The stock, which closed just above $35 a share, spiked about 6% in after hour trading.

Meanwhile, all three U.S. May indices ended the day in the green, extending Wednesday's rebound. Volatility dipped to its lowest level in about three weeks.

The U.S. 10-year treasury yield snapped a two-day winning streak to settle at 2.38%.