Trump Media’s Stock Plunges After Debate

Wall Street gave a thumbs down to former President Donald J. Trump’s debate performance on Tuesday night, judging by trading on Wednesday in shares of his social media company.

Shares of Trump Media & Technology Group, the parent company of Truth Social, fell more than 10 percent by the market’s close on the day after the debate between Mr. Trump and Vice President Kamala Harris.

Since Trump Media’s debut on Wall Street in March, the company’s stock has traded as something of a proxy for Mr. Trump’s prospects in the November presidential election. Commentators, including members of Mr. Trump’s Republican Party, concluded that Ms. Harris put him on the defensive and provoked him into veering off message.

Shares of Trump Media, which were down as much as 15 percent on Wednesday, have fallen to their lowest level since the money-losing company went public in March, after its merger with a cash-rich shell company, Digital World Acquisition Corporation.

The sell-off in shares of Trump Media has come at an inauspicious time for Mr. Trump, who owns about 57 percent of the company’s stock. In just over a week, on Sept. 19, a provision that prohibits him and other large shareholders from selling stock is set to expire.

Mr. Trump’s shares were worth a just under $2 billion at the market’s close on Wednesday. Trump Media’s falling share price has reduced the paper value of his stake in recent months by about $4 billion.

Mr. Trump now faces a decision: Should he start selling some shares to cash in now or hold them, at least until after the election? If he were to sell, a flood of new shares in the market could put more pressure on the stock and risk alienating some of his most loyal supporters — the more than 600,000 individual investors who are Trump Media shareholders.

The company’s stock closed at $16.68 on Wednesday. If it were to drop below $12, the restriction on Mr. Trump’s selling his shares could be extended to Sept. 25, according to a provision in the lock-up agreement.