SpaceX bears are smelling blood in the water. As its stock languishes below its IPO price  — at press time, $131 — short sellers are going all in against the company, hoping to make a killing off of CEO Elon Musk’s faltering pull on investors.

As CNBC reports citing data from S3 Partners, 185 million SpaceX shares are now sold short, which is nearly 29 percent of its publicly tradable shares, when it was around only five to seven percent three weeks ago.

It’s one of the highest levels of short selling for a company in its first month of being publicly traded, Ihor Dusaniwsky, a managing director at S3, told Bloomberg.

“The recent price weakness has spurred short selling as well as the anticipation of lockups expiring soon,” he added, referring to the additional SpaceX shares that will soon be tradeable and will play a large role in how the stock performs.

SpaceX priced its IPO at $135 a share and seemed to set the tone when its price rose to $150 on its opening day and powered past $200 in the days that followed. Those blockbuster gains were short-lived, however. Its price has steadily declined over the past month, losing a third of its value since its peak.

Investors have questioned Musk’s vision for the company — which includes an ambitious pivot to building orbital AI data centers — while its path to profitability remains unclear. Last year, the company lost nearly $5 billion.

Musk’s decision to combine SpaceX with his AI startup xAI before the IPO has also exposed the rocket company to xAI’s numerous controversies, such as its chatbot Grok being used to generate millions of nonconsensual sexualized images of real people. Before, the public fascination around spaceflight had helped shield SpaceX against anti-Musk sentiment.

Off the back of this waning enthusiasm, short sellers have seen their paper profits surge to $3.88 billion, Bloomberg reported Wednesday.

But the next few months could be a key turning point for the stock’s performance — or further sink its hopes. Only a small percentage of SpaceX’s shares were made available when the company went public as a measure to prevent insiders from quickly cashing out and crashing the stock price. But around half of its shares will be unlocked from now until December, dwarfing what’s currently available.

If investors dump those unlocked shares, it could send SpaceX’s stock tumbling. Experts have warned that this period of gradually unlocking stocks could be considerably volatile— which isn’t exactly reassuring, given the company’s recent performance.

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