Billionaire Mark Cuban used this sales pitch for his first tech startup in 1989—here's why it worked

When Mark Cuban launched his first tech startup, he couldn't have known he'd end up a billionaire today.

He was confident, though, that his sales pitch for the company — a software startup called MicroSolutions — would work.

In a recent post on X, formerly known as Twitter, Cuban shared a 544-word excerpt of proposal he sent in 1989 to a law firm he hoped to land as a client, Dallas-based Jenkens & Gilchrist.

In the proposal, Cuban wrote that his tool would be a great resource for attorneys looking to streamline their workflow — by having information "immediately published electronically to the organization," as opposed to using notebooks.

"Imagine being able to print or view a columnar report showing strategies by trial, with the opposing firm, judge and results!" he wrote. "The opportunities for a competitive advantage are limitless, as are the ability to demonstrate to current and prospective clients the power of the qualitative tools available."

The pitch worked, he added.

"And yes, we closed the deal. Basically, it was our version of Slack long before Slack," Cuban wrote in a follow-up post. "My big pitch back then was, 'Post once, published everywhere.'"

The proposal relied on Cuban's No. 1 key for making a sale, which he learned at age 12 while selling garbage bags door-to-door: "You're not trying to convince people. You're trying to help them," as Cuban told GQ last month.

"It's all about putting myself in your shoes," he added. "It's, 'I really think that this can be a better solution for you. And if I find you a better solution, will you do business with me?'"

If Cuban could go back in time and tell his younger self one thing, it'd be to keep honing his sales skills, he noted in a TikTok video posted last year.

"Once you learn how to sell, you can always start a business [because] you're an entrepreneur at heart," said Cuban.

A year after sending his pitch to the law firm, Cuban sold MicroSolutions to now-defunct internet services company CompuServe for $6 million. He ultimately became a billionaire after his next startup, internet streaming service Broadcast.com, sold to Yahoo for $5.7 billion in 1999.

His current net worth is $5.2 billion, according to Forbes.

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

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