Musk on Monday exercised the options at a price of $6.24 per contract, according to a regulatory filing Wednesday. He subsequently sold 934,000 shares to collect about $1.1 billion.

The shares were sold “solely to satisfy the reporting person’s tax withholding obligations related to the exercise of stock options,” the filing said. The contracts, which came from a stock option award Musk received in 2012, were set to expire in August next year. 

Tesla rose 4.3% on Wednesday to close at $1,067.95, paring losses this week to less than 13%. The decline on Monday and Tuesday wiped out $50 billion from Musk’s net worth.

It’s the billionaire’s first sale since 2016, when he last exercised stock options and liquidated some of his newly acquired shares to cover about $590 million of income taxes.

The sale was prompted by a Nov. 6 poll Musk set up on Twitter, saying that “much is made lately of unrealized gains being a means of tax avoidance, so I propose selling 10% of my Tesla stock.” Almost 58% of the 3.5 million votes were cast in favor of a sale.

Musk, 50, is the world’s richest person with an almost $300 billion fortune, according to the Bloomberg Billionaires Index. His common shares in Tesla make up about 60% of it. That indicates Musk may carry out additional sales to fulfill his promise.

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