Elon Musk offloads another $930 million in Tesla shares as he continues his selling streak

• Tesla CEO Elon Musk has sold more than 934,000 shares in the electric-car company.
• The sale comes as the Tesla CEO exercised options buy 2.1 million stocks at $6.24 each.

Elon Musk has sold more than 934,000 Tesla shares worth $930 million, US Securities and Exchange Commission (SEC) filings showed on Monday.

The sale comes as the Tesla CEO exercised options to buy 2.1 million stocks at $6.24 each, one of the filings showed. Musk is required to pay income taxes on the difference between the exercise price and fair market value of the shares, which closed at $1,013.39 on Monday.

It's the second time in less than two weeks that the billionaire has exercised his stock options. On November 8, Musk exercised options to acquire nearly 2.2 million shares, a regulatory filing shows.

Today's stock sale comes after Musk sold $6.9 billion worth of shares last week. Earlier this month, he also conducted a Twitter poll asking whether he should sell 10% of his stock to pay taxes, vowing to abide by the result, which turned out overwhelmingly positive.

Some of the billionaire's stocks sales today are part of a trading plan established in September, the SEC filings show.

Musk still has millions of stocks options he needs to exercise before their expiry next August.

Musk's Twitter survey and share sales come amid intense debates in the US over whether the wealthy are paying enough in taxes. The Tesla CEO is the richest man in the world, with a net worth of $279 billion, according to the Bloomberg Billionaires Index.

On Sunday, Musk mocked Bernie Sanders on Twitter after the senator said the extremely rich should pay their "fair share" of taxes.

"Want me to sell more stock Bernie? Just say the word," Musk tweeted to Sanders in response. Tesla shares tanked as much as 5% in Monday's session, and were down 1% in after-hours trading.