This is the first thing Ring's founder bought after selling his company to Amazon for $1 billion

Jamie Siminoff.
Eric McCandless | Contributor | Getty Images

Most people, upon selling their company to Amazon for $1 billion, might buy a flashy new watch, a luxe sports car or even a mega-mansion. Some might find themselves buying a few of each.

Not Jamie Siminoff. The founder of Ring, a home security start-up, bought a mountain bike.

Granted, it's not your basic bike. It was a treat that Siminoff had been eyeing for awhile: a specialized, S-Works Epic mountain bike. At $8,000, Siminoff calls it a "total splurge."

"I literally had it picked out," Siminoff recalls to CNBC Make It. He says he and his future boss at Amazon went for a walk during the due diligence process. "We walked by the bike store, and it was in the window. And I said, 'That's what I'm going to buy if it [the deal] closes.' And he was like, 'Cool, it's a great bike.'"

The bike was hard won. Siminoff strode onto the national stage in 2013 as a contestant on "Shark Tank." Back then, his company was losing money and could barely cover its costs. He and his team spent a month on the company's pitch and spent $10,000 to prepare. He left without a deal, devastated.

"The drive home sucked," he said in one interview.

Siminoff was already a success in his own right, however, having built and sold a slew of other companies, some fetching millions of dollars. Free publicity from the show helped boost sales, getting the company back on track. "Nothing will ever supersede 'Shark Tank,'" he's said. "We'd have been gone."

Still, Ring's success was far from instant. The company faced other challenges, such as a recent legal dispute with another home security company that temporarily put Ring's sale to Amazon on hold. In the end, Ring prevailed to the tune of $1 billion. He returned to the "Shark Tank" stage this past Sunday, this time as a guest judge.

In many ways, the bike was a fitting way to mark his new role. No longer a CEO, he's free to create. At his start, Siminoff often used his home garage as an office and as a workshop to tinker and invent. It was in that garage he actually stumbled onto the idea for Ring. Frustrated he could not hear his doorbell from the garage, Siminoff built himself a WiFi-enabled video doorbell.

Siminoff says he's excited for the freedom he has now: "I called myself a Chief Inventor at Ring. I didn't call myself a CEO for a very specific reason. I like inventing and building product much more than building a business."

"That's really all I wanted to do."

Amazon is buying "Shark Tank" reject company Ring for $1 billion
Amazon is buying "Shark Tank" reject company Ring for $1 billion

Don't miss: Behind-the-scenes 'Shark Tank' secrets from founder of 'Tank' reject Ring, which Amazon bought for $1 billion

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

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