Sauber used Ferrari designed engines from 1997 to 2005. They were built by Sauber Petronas Engineering, a company founded for purpose of building these engines. The engines were nearly identical to the ones used by Ferrari. Sauber Petronas Engineering also built the gearboxes used by Sauber. Sauber licensed nearly every part they could from Ferrari. Sauber even had several Ferrari engineers on staff. Suspicious similarities between Ferrari and Sauber chassis were pointed out, but no formal accusations were ever made. The FIA rules require each team to design their own chassis.