Musk and Zuckerberg are dumping stocks at a historic pace — should you be worried?

According to the Wall Street Journal, executives have been selling stocks at historic levels as market valuations soar and before tax laws in the U.S. and some states could change.

An Analysis by the Wall Street Journal of research firms shows that so far this year, 48 executives have each earned more than $200 million through stock sales, nearly four times the average number of insiders between 2016 and 2020.

And, of course, that includes Elon Musk, who has recently been dumping billions of dollars in Tesla stock at a very fast and steady pace.

Executives on the list also include billionaire Ronald Lauder and Google co-founders Larry Page and Sergey Brin.

According to the Wall Street Journal, Lauder sold 2 million shares this year with a pre-tax value of more than $600 million, his first sale since 2016, while Page and Brin each sold nearly 600,000 shares worth about $1.5 billion.

Microsoft CEO Satya Nadella sold half of his stake in Microsoft last month for about $374 million before tax. Analysts believe the move could be related to a 7 percent tax on long-term capital gains imposed by Washington state next year.

In addition, Walmart wealth heirs Walton family and Meta platform CEO Mark Zuckerberg is expected to sell more stocks this year than ever before.

This is unprecedented. These sell-offs are reminiscent of those during the dot-com bubble. But this may be a normal trend, with insider stock sales tending to go up and down.

Investors sometimes worry that a massive sell-off by insiders means they don't expect a further sharp rise in the stock price, while an unexpected mass sell-off could drag down the stock price. Still, experts note that the biggest sell-off came after a potential tax hike as part of the Rebuild Better plan, which was reflected in a total of $15.59 billion in November insiders.

Beginning in 2022, the bill would impose a 5 percent tax on adjusted gross income over $10 million and a 3 percent tax on income over $25 million, including capital gains from stock sales, according to the Wall Street Journal. Wealthy taxpayers save up to $8 million in taxes for every $100 million they sell before the effective date.