Shares of Chinese electric vehicle maker Nio tumbled nearly 9% in Hong Kong trading after Singapore’s sovereign wealth fund GIC filed a lawsuit accusing the company of inflating its revenues and violating U.S. securities laws.

According to a court filing in the Southern District of New York in August, the lawsuit names Nio CEO William Li (Li Bin) and former Chief Financial Officer Feng Wei as defendants. GIC alleges that Nio misrepresented its financial results to investors, resulting in artificial inflation of its stock price.