Thiel's take on Andreessen, Icahn and Captain Kirk

Thiel & Andreessen agree about Icahn
Thiel & Andreessen agree about Icahn

Peter Thiel says he and fellow Silicon Valley venture capitalist Marc Andreessen may not agree on terminology, but they have similar thoughts about Carl Icahn.

"I don't like 'Star Trek' references, but other than that I would agree with Andreessen," Thiel said Monday on CNBC's "Squawk on the Street."

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After Icahn tweeted last Wednesday that he would send an open letter to Apple CEO Tim Cook, Silicon Valley pioneer Marc Andreessen called the activist investor an "evil Captain Kirk."

Andreessen later told CNBC that some activist investors were mentors while others, such as Icahn, didn't care much for the companies involved, a situation similar to the two good/bad versions of the captain of the star ship Enterprise.

Andreessen: Icahn like the 'evil' Captain Kirk
Andreessen: Icahn like the 'evil' Captain Kirk

In a letter a day after the tweet, Icahn said Apple shares were "dramatically" undervalued, and he wanted the company to buyback shares.

There's "always the perspective that these companies shouldn't be investing in technology, [that] they should be investing in their own share price," Thiel said. "That assumes that the iPhone will be able to maintain its monopoly-like profit margins for decades to come, and there's a sense that this is quite unstable."

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