IHS Markit estimates in its most recent reading that $11.4 billion worth of Tesla shares are currently sold short, representing 26% of its equity free float, or shares available for public sale. In dollar terms, that puts it atop the list of most outstanding short interest, followed by Amazon and Apple, which IHS Market estimated have $8.8 billion and $7.9 billion, respectively. Where the short interest differs between Tesla and the two largest U.S. companies is that Amazon's short interest represents only about 1% of its $928 billion market cap, and Apple's, about 1% of its $1 trillion market cap.
Shares of Tesla are up about 8.4% on the year, but down a little more than 1% since the start of the third quarter after erratic rhetoric from its founder, Elon Musk, responding to analysts and investors who have grown tired of the company's rapid cash burn and unprofitable ways. Mr. Musk posited on Twitter that he might follow Michael Dell's route and take his company private, a move that has sparked market-manipulation lawsuits and stock price volatility.
Among the other companies with significant short-seller activity, Amazon, Apple, Netflix and Microsoft have returned an average 47% since the end of 2017.