CoStar Group, Inc. ( CSGP - Free Report ) was a big mover last session, as the company saw its shares rise almost 8% on the day. The upside was driven by the company's strong results for first-quarter 2017, which topped estimates. Also, this led to far more shares changing hands than in a normal session. This continues the recent uptrend for the company as the stock is now up over 14% in the past one-month time frame. The company has seen no positive or negative estimate revision in the past 30 days.