Mark Cuban Missed Out on Billions from Uber, Passed On Early Investment

"Shark Tank" star Mark Cuban has a ton of money, but his wealth could've actually grown by a couple more BILLION if he would've taken an early opportunity to invest in Uber ... a move he's regretting to this day.

The billionaire investor and entrepreneur talked about the deal that got away on an episode last month of Kevin Hart's "Hart to Heart," saying he was offered the opportunity to put some dough into the company in 2009 -- years before the ridesharing game took off.

Mark says it was a $250k investment at a $10M valuation -- for the "Shark Tank" fans doing the math, that would've given him 2.5 percent of the company. While the other sharks might've laughed that valuation off, Mark's $250k would've been $2.25 BILLION today.

Mark says he offered to give the cash if the company was valued at $5 million, but he claims he never heard anything back ... and they eventually got someone else to fill his spot. As you can guess, he's vowing to never make a mistake like that again.

Kevin says he also had the chance to put $50k down on the brand years ago ... but thought the idea of strangers driving each other around sounded like "Murderville."