On Wednesday, Marc Andreessen criticized investor Carl Icahn for his method of activism. Icahn responded Thursday.

"I'm no great fan of Andreessen ... I tried to listen to him but he talks in a high squeaky voice and, you know, when he talks you can't really hear him in my opinion," Icahn said on CNBC's "Fast Money: Halftime Report."

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Icahn also said Andreessen represents the bad side of the tech industry, saying that "it's sort of a known fact" that he has "screwed more people than Casanova."



The activist investor accused Andreessen of having stolen Skype from eBay.