After-Hours Movers Monday: Green Dot Corporation, Sonic Corporation

Green Dot Corporation GDOT rose more than 27 percent in Monday's late session to $19.50. The bank holding company authorized a plan to buyback up to $150 million of its common stock and said it will continue to serve as the issuing bank for the Walmart prepaid debit cards. Comstock Resources Inc CRK rose about 5 percent in late trading to $4. The Frisco, Texas-based oil and gas company didn't issue news. Humana Inc HUM gained about 4 percent after the bell to $197.93. The shares closed down about 6 percent earlier. Aetna Inc AET reportedly made an offer last week for Humana although details weren't disclosed. Epizyme Inc EPZM extended its gains in Monday's extended trading, rising more than 2 percent to $26.57. The drug development company gained more than 25 percent before the bell on favorable data concerning Phase I data on its non-Hodgkin lymphoma treatment. Peabody Energy Corporation BTU picked up nearly 3 percent after the bell, trading at $2.70 a share. The coal company is off about 66 percent in the year to date and said Friday it will sell properties in Australia. Calithera Biosciences Inc CALA increased more than 2 percent in late trading to about $8.92 a share. The company didn't issue news Monday. Sonic Corporation SONC fell about 5 percent after Monday's closing bell to $32.40. The restaurant chain posted disappointing quarterly earnings. PTC Therapeutics, Inc. PTCT bounced down about 3 percent to $50.70. The biopharmaceutical company gained 6 percent before the bell and didn't post news. Intevac, Inc. IVAC gave back about 3 percent, trading at $5.83 after the bell. The company, which supplies manufacturing equipment to disk drive makers, gained 10 percent earlier Monday on no obvious catalyst. Darden Restaurants, Inc. DRI declined 2.9 percent to $67.35 in late trading. The company is set to post quarterly results Tuesday and didn't issue news.