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Some of the most shorted stocks by hedge funds have been the biggest winners this year.
Hedge funds' biggest short position right now is Tesla, which has a negative 1.7% overall weight among the funds, according to Jefferies' calculations. The electric carmaker has soared nearly 50% this month alone, bringing its 2020 meteoric rise to almost 600%.
China-based electric vehicle maker Nio has also been a popular short bet among hedge funds, Jefferies said. The stock has popped even more than Tesla, up a whopping 1,173% this year. Another most-shorted position Trade Desk has also more than doubled in 2020.