Public prosecutors in Stuttgart said Thursday they had launched a probe into possible insider trading in shares at German-US auto giant DaimlerChrysler at about the time that chairman Jürgen Schrempp said in July that he would step down early. Prosecutors decided to launch the probe based on information gathered by the German financial sector watchdog, BaFin, which had been carrying out a routine investigation of the carmaker, a spokeswoman for the prosecutors said. She did not provide any further details. Schrempp said at the end of July that he planned to step down at the end this year, three years before his contract expires. The probe concerns a surge of about 10.0 percent in the price of shares in DaimlerChrysler on the Frankfurt stock exchange at about this time.