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You’d think a billionaire making his email public would turn into a spam nightmare. But for Mark Cuban, staying open to public emails and skipping the usual red tape comes with an edge that outweighs the noise.

Speaking on comedian Theo Von’s podcast in September 2024, Cuban said he’s spotted several new investment opportunities from cold emails. One of those messages led him to invest $500,000 in a space exploration company that later became a competitor to Elon Musk‘s SpaceX.

“They wanted to start a space company, I’m like, I don’t know s**t about space but I’ll get you started and see what happens,” Cuban said. “It’s called Relativity Space, I still never met him, it was all email. I’ve invested a few million, they’re worth $4 billion.”

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Relativity Space, founded in 2015 by Tim Ellis and Jordan Noone, uses advanced 3D printing and robotics to build rockets.

‘I Got Lucky’

Cuban gave credit for the company’s success to its founders and said he simply provided capital to get them started because he saw their potential and capability early on.

“It’s not like I helped them get there,” he told Von. “Guys were just insanely smart and good, so I got lucky.”

Relativity Space isn’t the only startup Cuban got involved with through cold emails. His entry into the pharmaceutical industry, which led to one of his most disruptive ventures, started with a cold email from Dr. Alex Oshmyansky, he told Von.

“He said that there are a lot of generic drugs that were in short supply and kids can’t get their medicine, and I’m like well, what can we do about that,” Cuban said. “So we decided to create this company called Cost Plus Drugs.”

Cuban’s approach highlights a broader shift in how early-stage capital flows are forming outside of traditional venture networks, with some investors increasingly gaining exposure to private-market opportunities through more direct or unconventional channels. Platforms focused on alternative assets and fractional access to private investments have also grown in popularity as retail investors look for ways to participate in segments of the market that were once limited to institutional backers.

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‘Opens a Lot of Doors’

Another major Cuban investment success story that started with a cold email is cloud storage company Box Inc. (NYSE:BOX). Co-founder Aaron Levie sent cold emails in 2005 to dozens of potential investors, including Cuban, to help scale the startup. Cuban replied within hours and showed openness to a partnership that led to a $350,000 investment. Box later went public and now has a market value of about $3.6 billion.

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Some other startups Cuban has backed after cold emails include food-tech company SAVRpak, college sports merchandise platform Campus Ink and decentralized finance platform Injective.

“Sometimes just making yourself available opens a lot of doors, and it’s helped me a ton,” Cuban told Von.

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This article I ‘Never Met Him, It Was All Email’ — Mark Cuban Says He Invested $500K After a Cold Email, That Company Became a $4B SpaceX Rival originally appeared on Benzinga.com

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