French retail giant Casino has bought 7.46 million shares in Colombia's Almacenes Exito, increasing its stake in the Colombian retail chain by 3.07%. Casino, France's second-largest supermarket company, now holds a 30.27% stake in Exito, reported Reuters. Bergsaar, a subsidiary of Casino, paid US$15.7m in the auction at a premium of 79.7% above the stock's closing price on Friday.