Buy-and-hold investor Ron Baron told CNBC on Tuesday his biggest mistake was not investing in Jeff Bezos' Amazon.
"I didn't invest in him. How could I miss it?" said Baron, the billionaire founder of Baron Capital, which has $28.3 billion in assets under management.
In an interview on "Squawk Box," Baron said that back in 1999, his firm was suffering from a huge investment loss in Sotheby's, which was implicated in a price-fixing scandal. At the time, Baron said he was trying to persuade Bezos to invest in Sotheby's.
"Here I am trying to get him to buy this company that I have an investment in and I'm trapped instead of focusing on, 'Oh my God, this guy has changed the world,'" Baron said. "My biggest mistake was not investing in Amazon."
Since Dec. 31, 1999, Amazon's stock is up 2,533 percent. Amazon, with a market cap of more than $977 billion, has seen its share rise 71 percent so far this year. In June 1999, Bezos announced a deal between Amazon and Sotheby's to start a collectible bidding site, a venture which ultimately failed.
E-commerce giant Amazon has been aggressive in recent years on expanding its retail muscle, including through partnerships and major acquisitions.
Baron has made billions of dollars by doing extensive research, buying the stocks of what he feels are undervalued companies, and keeping them for an average of about 14 years.
Baron's comment on Amazon came the same day the e-commerce giant announced it was raising its minimum wage for all U.S. employees to $15, effective next month.
In the same CNBC interview Tuesday, Baron also commented on his investment in Tesla. He said the electric automaker could be a $1 trillion company in revenue by 2030.
—CNBC's Michael Sheetz contributed to this report.