This 'Shark Tank' investment just made Mark Cuban a few million dollars richer

Billionaire Mark Cuban just added a few more dollars to his bank account.

In 2014, the business maverick and "Shark Tank" star invested $1.75 million for a stake in Boston-based obstacle course company Rugged Maniac, making it one of the biggest deals on the show. Now, the Dallas Mavericks' owner is cashing out.

According to the Boston Globe, New Media Investment Group recently acquired an 80 percent stake of Rugged Maniac for $10.4 million. Business partners Rob Dickens and Brad Scudder will hold on to the rest.

Cuban sold his entire stake, "essentially doubling his initial investment," according to the Boston Globe.

The former lawyers won Cuban's financial support on season five of the reality TV show. Since then, they've turned to him for entrepreneurial advice and credit Cuban with teaching them one valuable business lesson: Know your worth.

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Mark Cuban

The then 27-year-old Scudder founded Rugged Maniac in 2010. At the time, "I was practicing law and I hated it," he tells CNBC Make It. "I was looking for anything else to do."

The entrepreneur, 34, describes himself as an "outdoorsy guy" who grew up on a farm in the western part of Massachusetts.

Tired of his boring day-to-day corporate job, he decided to partake in a tough mudder obstacle course — a series of 10 to 12-mile obstacle race events.

This experience inspired him to create his own company with shorter obstacle courses, such as muddy water slides, tunnels, fire pits and large scaling walls.

During the day, Scudder worked his standard 9-5 job as a lawyer. But at night, he pored over his business plan, sought out a website designer, found a venue and built obstacles in a horse patch. Four months in, the CEO left his lucrative job as an attorney to focus solely on his burgeoning business.

"People thought I was crazy," says Scudder. "I was traveling 200 days a year, coming in at 3 a.m. in the morning, working 80 to 100 hours a week."

He was also forced to live with four roommates in a rough neighborhood in Boston just to make ends meet.

"I got through with a lot of help from my friends and family," says Scudder. But when 1,500 people signed up for his first obstacle event, he knew he was onto something.

The founder soon brought on his friend and former Wall Street lawyer Rob Dickens. Together, they grew the business over the next three years, churning out about 15 events a year.

As the company expanded, the partners caught the eye of "Shark Tank" producers, who reached out to invite them on the show. At first, Scudder and Dickens turned down the opportunity but eventually accepted the offer.

"The exposure was too good to pass up," says Scudder. In fact, he still remembers the exact moment that he came face-to-face with Mark Cuban and the full panel of judges.

"I was like, 'oh s---. These people are going to rip me apart on national television,'" Scudder recalls. "I thought I was going to pass out."

To the contrary, Cuban saw their company as a major investment opportunity and initially offered them $1.5 million. Although Rugged Maniac was barely profitable at that point, says Scudder, they rejected the offer.

The three finally settled on a $1.75 million investment, with Cuban getting a 25 percent share of the company.

Tony Rivetti | ABC

Now in its eighth year, Rugged Maniac operates over 30 events nationwide with more than 150,000 participants annually.

According to Scudder, the company has seen 100 percent growth year-to-year, which he admits is influenced by Cuban's backing. "He's a brilliant business mind," says Scudder. "He can reduce complicated issues to something super easy. He answers [questions] instantly and is straight to the point."

Looking back over his career, Scudder says that the best part of owning Rugged Maniac is the autonomy, adding that Cuban is pretty "hands-off."

"I'm my own boss. It excites me. I enjoy what I do," he says.

For other entrepreneurs looking to emulate his success, Scudder offers this key piece of advice: "You've gotta jump. [Rugged Maniac] must've been the 40th idea that I had. I thought I'd probably fail. You can't be paralyzed and stuck in inaction. Jump."

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Disclaimer: CNBC owns the exclusive off-network cable rights to "Shark Tank."

This is an updated version of a story that was originally published in 2017.