• Shares of Trump Media soared Monday, two days after former President Donald Trump returned to Butler, Pennsylvania, the site of his July 13 assassination attempt, to rally with Tesla CEO Elon Musk.
• Midway through Trump's 90-minute speech in Butler, Pennsylvania, Musk came up on stage to praise the Republican presidential hopeful and call himself "not just MAGA" but "Dark MAGA."
• Trump Media revealed in a regulatory filing Thursday that Chief Operating Officer Andrew Northwall resigned in late September.

Shares of Trump Media soared Monday, two days after former President Donald Trump returned to Butler, Pennsylvania, the site of his July 13 assassination attempt, for a campaign rally with Tesla CEO Elon Musk.

Shares closed up 11.45% at $18.39 per share after a heavy volume trading day. As of Monday's close, the media company had a market capitalization of about $3.681 billion.

In Butler, Musk came up on stage midway through Trump's 90-minute speech to praise the Republican presidential nominee and to call himself "not just MAGA" but "Dark MAGA."

"This is no ordinary election," said Musk. "President Trump must win to preserve the Constitution. He must win to preserve democracy in America."

The billionaire entrepreneur first publicly endorsed Trump for president in the hours after the July 13 failed assassination attempt. Musk has been a key supporter of the Trump campaign ever since.

Musk also created a pro-Trump political action committee, America PAC, which came under investigation earlier this year after voter data complaints. The probes have since been closed without further action taken against the PAC.

Trump, in turn, has said he would create a Musk-proposed government efficiency commission if he is elected president, to audit and cut waste throughout the federal government. Trump also suggested he would tap Musk to lead the commission.

In previous regulatory filings, Trump Media stated that the success of its chief product, Truth Social, depends on Trump's popularity and continued use of the platform. Trump owns nearly 57% of the company's stock.

Trump Media shares have been down 54.68% since a spike in July following Trump's first assassination attempt. Shares hit a new 52-week low on Sept. 23 and since then have been steadily recovering, despite recent reports of turmoil inside the company.

Trump Media revealed in a regulatory filing Thursday that Chief Operating Officer Andrew Northwall had resigned in late September.

In the same filing, the company announced it will release nearly 800,000 shares of its stock to an early investor by order of a Delaware judge, who found that Trump Media had breached an agreement with that investor.

Correction: This story has been updated to correct the date of Trump's rally.