Mark Cuban passed on an early Uber investment—his $250,000 would be worth $2.3 billion today: ‘Whoops’

Even billionaires kick themselves for passing on investment opportunities that turned out to be incredibly lucrative.

In Mark Cuban's case, he regrets not investing in Uber. He was offered the chance to invest at a $10 million valuation by Uber co-founder Travis Kalanick in 2009, and turned it down — because he thought the ridesharing company wasn't worth that much, he said on a recent episode of comedian Kevin Hart's Peacock talk show "Hart to Heart."

"Just think: If I would've given him $250,000 on a [$10 million] valuation, it'd be billions," Cuban said.

Specifically, given Uber's market capitalization of $90.1 billion as of Friday, Cuban's $250,000 would be worth $2.25 billion today. "I mean, I've done OK. But, still," said Cuban, whose net worth is currently estimated at $5.1 billion.

Cuban and Kalanick already had history at the time: Cuban invested $1.7 million in Kalanick's previous venture, a peer-to-peer networking startup called Red Swoosh, in 2005. When Kalanick sold the startup to cloud services company Akamai in 2007 for $18.7 million, "we made a little bit of money," Cuban said.

That meant he was receptive to Kalanick's Uber pitch. "He comes to me, like, first off [and says]: 'I've got this thing. It's going to replace taxi cabs..." Cuban recounted. "I was like, 'I love it.'"

However, Cuban said he didn't agree with Kalanick's $10 million valuation of the startup at the time: "I said, 'I'll do it at [a] $5 million valuation...' for Uber!"

"[Kalanick] never came back to me. He got somebody else. Whoops," Cuban said.

Passing on Uber was a shared experience for Cuban and Hart, it turns out. Hart lamented his own mistake of not investing as much as $75,000 in Uber early on, which he said could have made him "$100-plus million," had he jumped at the chance.  

Hart said music manager and Uber investor Troy Carter tried to convince the comedian to invest in the company before it became a household name. Carter described the company as "basically, like strangers giving people they don't know rides...' [and] I was like, 'This has to be the stupidest s–t I've ever heard'" Hart said.

"Don't feel bad," Cuban replied, noting that he probably missed out on a greater return than Hart would have seen.

Cuban said he did offer Kalanick some advice on the likely significant obstacles Uber would face, including the major regulatory pains the company would endure and "dealing with all of the taxicab commissions that are going to try to put you out of business."

The years-long regret of failing to invest in Uber has stuck with Cuban. At SXSW in 2017, the billionaire was adamant that he doesn't plan on missing the boat on any more disruptive startup ideas, like he did with Uber.

"If you really believe and you really have something that you think is going to disrupt the world, bring it to me," he said. "I won't make the same mistake twice."

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank," which features Mark Cuban as a panelist.

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