VCs Bill Gurley, Peter Thiel clash over Uber

Uber mass market phenomenon: Bill Gurley

The lofty valuations of some Silicon Valley start-ups have come into question lately, with a few noted venture capitalists arguing over ride-sharing service Uber in particular.

Bill Gurley, who led investments in many noteworthy tech start-ups, including Snapchat and Twitter, defended the ride-sharing service in a CNBC interview on Monday.

"It's the fastest growing company we've ever been involved with," Gurley, a general partner at Benchmark, said on "Squawk Alley." "That's why, when the company was, you know, put in front of a large number of investors, that you ended up with the valuation that it did."

The company, which allows users to call a taxi, private car or ride share through its mobile app, currently ranks among the top 10 free apps on the Apple App Store, Gurley said. In turn, the company has added roughly 50,000 new drivers a month, he added.

Thiel: Tech stocks not core of insanity

But in a recent CNBC interview, venture capitalist Peter Thiel took a potshot at Uber, claiming the company is overvalued.

"Investors are always biased to invest in things they themselves understand. So venture capitalists like Uber because they like driving in black town cars," he said last month on "Squawk on the Street." "They don't like Airbnb because they like staying in five-star hotels, not sleeping on people's couches."

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"And so Uber is overvalued," Thiel said. "Airbnb is undervalued."

Gurley dismissed Thiel's comments, though, saying the two companies have nothing to do with one another.