It’s remarkable to sell your company for $900 million. But it only gets sweeter when you find out you’ve become a billionaire in the process.

Div Turakhia, 34, sold his 5-year-old ad-tech company, Media.net, to Beijing-based Miteno Communication Technology last month. The near-billion dollar acquisition is the third-largest in the industry’s history, behind Microsoft’s (MSFT) acquisition of aQuantive for $6 billion in 2007 and Google’s (GOOGL, GOOG) purchase of DoubleClick for $3 billion also in 2007.

The Media.net deal stands out in the competitive ad-tech industry. Apart from a few hot exits, including Wednesday’s IPO of California-based The Trade Desk, the ad-tech industry has cooled down significantly.

Turakhia said Media.net’s primary differentiator is its focus on the technology behind auto-generating ads on websites.

“More than 1,000 ad tech companies have been funded, but very few of them have a large enough platform,” he told Yahoo Finance in an interview Thursday. “Most of them have been so focused on sales and marketing.”

Media.net by the numbers

Media.net delivers more than 800 million paid ad clicks every year to advertisers, most of which are large publishers. Last year, the company generated $48 million in net income. Undeniably, Turakhia’s ability to generate profits as a private company contributed to Media.net’s appeal to potential buyers: Turakhia whittled down the final list to seven bidders.

Media.net received offers of around $700 million to $750 million, mostly from the private equity world. But ultimately, he said, Miteno was the best fit not only because it offered the highest bid, but also because it opens the door to China — the world’s second largest ad-tech market.

“If you don’t have a local partner you can’t really grow in China, so we saw this as a huge advantage,” he said.

And with 90% of Media.net’s revenues coming from the US, this deal allows Turakhia to double down on international expansion, particularly in Asia and Europe.</>

Bootstrapping the business

When building the company, Turakhia did not take any venture capital and owned 100% of Media.net prior to the sale; it was funded entirely by the profits of his other companies.

“I didn’t raise separate funds for it. Bootstrapping is definitely harder … but this is also not my first bootstrap business. I’ve built a bunch of businesses with my brother, and they were all bootstrapped. I’ve been able to identify what I can build,” he said.

Ultimately, Turakhia says he’s always followed his passion and hasn’t sought out money — though making the billionaire list doesn’t hurt, of course.

“It’s never about the money. The money is great because it allows you to keep score. It allows you to know you’re moving in the right direction when you’re building incredible things,” he said. “If you’re really passionate and you build cool things, the money will follow.”

Melody Hahm is a writer at Yahoo Finance, covering entrepreneurship, innovation and technology. Follow her on Twitter @melodyhahm.

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