BYD Co, the Chinese electric-car maker backed by Warren Buffett, fell the most in two weeks in Hong Kong after Chardan Capital Market LLC advised investors to sell the stock following a fivefold jump in the share price.

The company dropped as much as 7.6 percent, the biggest intraday decline since Nov 2. It closed down 6 percent at HK$64.65.

BYD is overvalued as it's trading at 37 times next year's earnings, a premium to peers, Chardan said. Investors replicating Buffett's strategy have caused the automaker to surge since the billionaire's Berkshire Hathaway Inc agreed to buy a stake last year.