Twitter's valuation is in the eye of the beholder, Aswath Damodaran of the New York University Stern School of Business said Tuesday.
"I really think it depends on what you call yourself. If you're a trader, then all bets are off. You're betting on price," he said.
"If you're an investor and you think about value, I think at $20 billion, an awful lot has to go right for that $20 billion to be a break-even, forget about making money."
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