"If that were to happen, it would be an attack on intellectual property. 50 percent of the company is being taken away - this, effectively, is expropriation," Wolf said.
"I believe this is an attempt to make up leeway in terms of know how and innovation."
Robert Bosch and Continental, Germany's two biggest automotive suppliers, could not immediately be reached for comment.
Read MoreEuropean companies slam Chinese antitrust probes
Earlier this month, the European Union Chamber of Commerce in China expressed concern over a recent series of antitrust investigations, saying China, the world's largest car market, was using strong-arm tactics and appeared to be unfairly targeting foreign firms.
At the time, the chamber said it had "received numerous alarming anecdotal accounts from a number of sectors that administrative intimidation tactics are being used to impel companies to accept punishments and remedies without full hearings."
The auto sector has been put under scrutiny from China's National Development and Reform Commission (NDRC), which has investigated car companies amid accusations by state media that global car makers are overcharging consumers.
Read MoreMercedes-Benz found guilty for price manipulation
"The Chinese state is noticing that 50 percent of the automotive world is taking place in China and that its manufacturers are not benefiting accordingly," ElringKlinger's Wolf told the paper.
European car brands including Volkswagen AG's Audi, BMW and Mercedes-Benz are scrambling to lower prices for new cars and spare parts in an effort to appease Chinese regulators who have accused some of them of anti-competitive behavior.
European and U.S. manufacturers are eager to increase their footprint in China, now the world's largest car market, but have been limited to owning 50 percent or less of joint venture companies run together with Chinese state-owned enterprises.