Kimbal Musk sold 88,500 of his Tesla shares on Friday, according to an SEC filing, a day before his older brother and Tesla CEO, Elon Musk, publicly launched his infamous Twitter poll. At an average price of $1,229.91, he made nearly $109 million as a result of the transaction.

The sale occurred on Friday, November 5 and amounted to roughly 15 percent of Kimbal’s stake in the company. It was not, however, made public until Monday afternoon, after Elon Musk asked Twitter if he should sell 10 percent of his stake in the company.

Elon’s sale would be worth about $21 billion, although the Twitter poll did send the share price falling about 12 percent. That’s the share’s worst two-day performance since March when famed investor Michael Burry said in a tweet that Elon Musk may sell shares to cover personal debts, reports the Los Angeles Times.

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If Elon sells the shares this year, it has also been pointed out, he may save millions in taxes. Kimbal and Elon aren’t the only ones taking advantage of Tesla’s incredible rally, which has seen the company’s share price rise by 1,600 percent in the last two years.

In October, company directors such as Ira Ehrenpreis, Robyn Denholm, and Antonio Gracias all sold shares that together are worth hundreds of millions of dollars, reports Business Insider.

Along with his position at Tesla, Kimbal Musk is the CEO of Kitchen Restaurant Group, as well as the founder of Square Roots Urban Growers Inc., an urban farming business. He has been on Tesla’s board since April 2004 and is also a director at SpaceX.