Billionaire investor Carl Icahn says red-hot inflation won't derail his investment approach — but thinks some stock valuations are 'out of this world'

Carl Icahn still believes that some stock valuations are too high, despite the fact that inflation isn't prompting him to rethink his investing strategy.

He told CNBC in an interview that he thinks there will be problems with inflation and other things. I don't let it bother me, I just keep going.

We keep a big hedge on.

Icahn is an activist investor who has a net worth of $23 billion. Activist shareholders build stakes in companies that are seen as cheap and then demand management changes that could work in their favor.

Icahn said that he thinks there are bubbles in the stock market.

Some of the multiples are crazy and some of the investments are out of this world.

A multiple is a calculation of value made by dividing the market price of a stock by the company's financials. These are used by investors to determine whether an asset is overvalued or undervalued.

Icahn doesn't think there will be a lot of trouble for the US economy in the near term.

He said that you don't have to be a genius to know that the Federal Reserve's pumping money into the economy will create inflationary trouble.

In December, US inflation increased by the most since 1982. Icahn said he was surprised it hadn't happened sooner.

No one can predict when the economy will be in trouble.

Who knows? I think it's going to be difficult. It could be now, and it could be three years from now.

Icahn said he was happy with the performance of the conglomerate last year.

In the first three quarters of the year, the net asset value rose by $1.8 billion. He said that had a lot of hedges on.

Another investor this week advised against investing in US equities and INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals INRDeals After the fourth "superbubble" burst, the S&P could crash 50%, according to Jeremy Grantham, the market historian who predicted the last three market bubbles.

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