According to The Wall Street Journal, China’s ride-hailing champion, after besting Uber, appears to be facing a tougher opponent in domestic regulators. Several major cities issued proposed industry regulations in recent days that would restrict the types of vehicles that can be used and who can drive them, potentially crimping a large chunk of Didi’s business. Meanwhile, the country’s antitrust regulators continued to investigate Didi’s deal to acquire US-based Uber’s China unit. Didi issued a strongly worded protest over the weekend against the draft regulations from Beijing, Shanghai, Shenzhen and at least three other major cities. The company said the rules, if adopted in their current form, would force “the vast majority” of its drivers and cars off the road.