Shares of Trump Media and Technology Group fell in midday trading Friday after President-elect Donald Trump transferred all of his shares into a revocable trust, according to a regulatory filing.

Trump transferred all of his nearly 115 million shares, worth about $4 billion on paper, to the social media parent company. Truth Social networking site as a “bona fide gift” to the Donald J. Trump Revocable Trust, the Securities and Exchange Commission said Thursday. Trump’s shares represent more than half of the company’s shares.

It is not clear why Trump transferred the shares. Donald Trump Jr. is the sole trustee and has sole voting and investment power over all securities owned by the trust.

Trump Media shares were down 2% at midday, to $34.68 each. At one point on Friday, they were down about 6%.

Shares of Trump Media have been extremely volatile since the company went public in March. They hit intraday highs near $80 on the first day of trading, then fell to record lows in September, when Trump and other insiders were finally able to sell shares after standard lock-up agreements expired. Trump has not sold any shares in the company.

The company’s stock price has fluctuated widely on Trump-related news, good and bad. They fell after Trump’s conviction in a hush money trial in May, then spiked after Trump’s first assassination attempt in July. They rose again after he won re-election in November, even as the company reported a loss of $19.2 million in the third quarter.

Trump created Trump Media after being banned from Twitter and Facebook following the January 6, 2021 Capitol riot.