Traders betting against Tesla are down more than $25 billion this year amid the stock's record-breaking rally

• Traders betting against Tesla are down $25.4 billion in mark-to-market losses, according to data from financial-analytics firm S3 partners.
• The short-seller losses come amid a blistering rally that's sent the automaker's shares to multiple record highs, up roughly 390% this year.
• Still, short-sellers are holding on — Tesla is still the top short in the US market, with $21.3 billion in dollars bet against the company, according to Ihor Dusaniwsky, managing partner of predictive analytics at S3.
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Traders betting against Tesla stock have racked up billions in losses amid the stock's epic rally this year.

Short-sellers with positions against Tesla are down $25.4 billion in year-to-date net-of-financing mark-to-market losses, according to Friday data from financial-analytics firm S3 Partners. The steep losses come amid a blistering rally that's sent Tesla stock up roughly 390% this year.

Traders betting against the automaker are down nearly $7 billion in August alone, and shed more than $1.3 billion in mark-to-market losses on Thursday, when Tesla surpassed the $2,000 level for the first time ever, according to S3 data. They've lost another $619 million Friday as the stock continues to climb ahead of its upcoming five-for-one stock split.

The automaker has had "continued steady short covering for over a year as shorts continue to get squeezed," said Ihor Dusaniwsky, managing director of predictive analytics at S3. Still, there are many short-sellers still holding on to their positions, S3 data show.

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Tesla is still the largest short in the US market, with $21.31 billion in short interest and 10.65 million shares shorted, 7.18% of its float. In July, Tesla became the first stock with a $20 billion bet against it.

The company has become a particularly popular target for short-sellers, perhaps in part due to CEO Elon Musk's public beef with the practice of betting against stocks — he's gone as far as saying the practice should be illegal.

Tesla has more dollars bet against it than technology giants such as Apple, which boasts a $2 trillion market value, Alibaba, Microsoft, Facebook, and Netflix, according to S3.

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