The president-elect suggested in a post on his social network, Truth Social, that those spreading the rumors are possibly acting illegally.

“There are fake, untrue, and probably illegal rumors and/or statements made by, perhaps, market manipulators or short sellers, that I am interested in selling shares of Truth. THOSE RUMORS OR STATEMENTS ARE FALSE. I HAVE NO INTENTION OF SELLING! I hereby request that the people who have set off these fake rumors or statements, and who may have done so in the past, be immediately investigated by the appropriate authorities,” he wrote in the post.

The Trump transition team did not immediately respond to Fortune’s request for comment. 

Trump’s declaration about not selling was his first personal message posted to Truth Social since he defeated Vice President Kamala Harris in last week’s election. (He’s posted much more since.) The post pouring cold water on any selling rumors, though, sent Trump Media shares soaring more than 10%, triggering a temporary halt before closing up 13% at $31.91 on Friday. The company’s shares were down 8.5% at $30.52 as of Tuesday.

Trump Media is the parent company of Trump’s social network Truth Social, and the president-elect owns about 57% of the company’s shares. As of Tuesday, his more than 114 million shares in the company were worth about $3.5 billion. 

Yet, while Trump has said he is not willing to sell his shares, Trump Media’s chief financial officer Phillip Juhan has filed to sell just over $13 million worth of shares in the company. 

The fate of Trump Media’s shares is closely tied to that of its multi-billionaire owner and can vary greatly. During Election Day, the company’s shares were halted three times after wild swings.

At $6.7 billion, its market cap is larger than some household names like Krispy Kreme doughnuts or Papa John’s Pizza—but its financials are much shakier. The company racked up $363.2 million in losses in the first three quarters of the year, while bringing in only $2.6 million in revenue. 

Prior to the election, Matthew Tuttle, the CEO of Tuttle Capital Management, told Fortune that if Trump were to lose, he expected the stock to lose all of its value. 

Still, the stock has defied expectations, and according to a recent report from financial analytics firm S3 Partners, short sellers betting against it have lost $420 million since the stock began tracking Trump’s election odds, Reuters reported.

Now that Trump is slated to take office in January, stocks are skyrocketing, with the S&P 500 and Dow posting their best weeks of the year so far last week. Bitcoin, the largest cryptocurrency, is also up about 27% over the past week.

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