Elon Musk has a net worth of more than $20 billion, according to Forbes. He's built it largely through growing electric car maker Tesla, a publicly traded company with a $57 billion market cap, and reusable rocket company SpaceX, now valued at $20 billion.
But Musk says one thing he doesn't do play the stock market.
"I think probably one of the biggest misunderstandings is that I actually am not an investor," said Musk during an interview at music and tech conference South by Southwest on Sunday.
"Sometimes people think I am an investor or that I invest in things. I actually don't invest in anything," he explains. "In fact, the only public security that I own of any kind is Tesla."
Though Tesla is not profitable and has repeatedly missed production goals, in February it announced fourth quarter results that beat analyst expectations, bringing in $3.29 billion in revenue versus an expected $3.28 billion. The stock closed at $341 on Tuesday. Musk owns about 20 percent of its shares.
After Tesla, Musk says his largest holding is in privately owned SpaceX.
And Musk doesn't invest in cryptocurrency either.
"I literally own zero cryptocurrency, apart from .25 BTC that a friend sent me many years ago," Musk tweeted in February.
Musk's strategy — investing only in companies he's built — is in line with something legendary investor Warren Buffett often advises: "There's one investment that supersedes all others: Invest in yourself."
Still, if you want to invest in the market, experts like Buffett recommend starting with low-cost index funds to spread your money across a diverse basket of companies.
"Consistently buy an S&P 500 low-cost index fund," Buffett told CNBC's "On The Money " in May. "I think it's the thing that makes the most sense practically all of the time."
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