Here’s when Wharton’s Jeremy Siegel says he would get more cautious on stocks

Jeremy Siegel
Scott Mlyn | CNBC

Wharton School finance professor Jeremy Siegel on Tuesday laid out scenarios that would prompt him to take a more cautious positioning toward the U.S. stock market.

One instance Siegel mentioned came in reference to earlier comments from billionaire investor Stanley Druckenmiller, who told CNBC earlier Tuesday that he had "no doubt, none whatsoever, that we are in a raging mania in all assets."

"I will be surprised if we're not out of the stock market by the end of the year, just because these bubbles can't last that long," the Duquesne Family Office CEO said on "Squawk Box." "But I really have an open mind and right now, treacherously, we're still playing the game to some extent."

In an interview on CNBC's "Closing Bell," Siegel said he heard Druckenmiller's remarks about potentially being out of the equity market. "And I was sort of wondering, well, it depends on where this market is," Siegel said. "If the stock market is up another 30%, I think I might be really shading down on stocks. If it is where it is today, I'd still be in it."

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