McLaren also announced that it was to reacquire the shares in its team from Mercedes-Benz (McLaren's partnership with Mercedes was reported to have started to sour with the McLaren Mercedes SLR road car project and tough F1 championships which included McLaren being found guilty of spying on Ferrari). Hence, during the 2010 season, Mercedes-Benz re-entered the sport as a manufacturer after its purchase of Brawn GP, and split with McLaren after 15 seasons with the team. This left Mercedes-Benz, Renault, McLaren, and Ferrari as the only car manufacturers in the sport, although both McLaren and Ferrari began as racing teams rather than manufacturers.