Uber is 'ethically challenged': Peter Thiel

Venture capitalist Peter Thiel says Uber is the most "ethically challenged" company in Silicon Valley.

"We do not invest in Uber. ... We do not look at it," the co-founder of PayPal and Palantir said on CNBC's "Squawk Box" in a wide ranging interview Wednesday.

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When asked why he didn't invest in Uber, Thiel said he "missed the boat early on" and now the ride-sharing company's valuation has gotten "too high for our liking."

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Thiel, who invests in Uber competitor Lyft, questioned the intensity of Uber's competitiveness.

"There's always a question, you know, how intensely you're allowed to compete, and Uber is right on the line," Thiel said.

Uber did not immediately respond to a CNBC request for comment.

-By Hailey Lee, for CNBC.com