Hedge fund founder Leon Cooperman said Tuesday he's been a buyer throughout the recent selloff, and he sees stock markets heading higher.
"Even though I think the market is in a zone of fair valuation, I think the market is not in a position in my opinion to go down a lot, and I think that the path is still upward," the Omega Advisors chairman and CEO said on CNBC's "Squawk Box."
His No. 1 reason for being optimistic: This would be the first bull market in history to end without one Federal Reserve interest rate tightening.
There have been eight interest rate cycles since the mid-1950s, and the market went up for 30 months on average after each rate hike, he said. In addition, the market was up 9½ percent one year after liftoff on average across those eight cycles.
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The Fed has held its benchmark federal funds rate near zero since December 2008, but could raise it for the first time in more than nine years when the Federal Open Market Committee meets Sept. 16-17.
Cooperman said he believes the economy is strong enough to absorb higher interest rates.
"I think the Fed's been somewhat irresponsible," he said, citing strong automobile sales and continuing employment growth. "There's no basis for zero rates."
Cooperman's second reason to be optimistic is his belief that bear markets don't "materialize out of immaculate conception," but because investors anticipate the onset of recession.
He noted that at a recent gathering convened by Blackstone Advisory Partners' Byron Wien, not one of 21 distinguished guests saw a recession coming.
Thirdly, Cooperman said stocks still represent the best option among financial assets.
"Common stocks are in line with their historical norms, not overpriced, and you can find so many attractively priced stocks," he said. "I think stocks are still the most attractive house in the financial asset neighborhood."
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To be sure, stocks are not cheap, he said, "I think the market's priced to give you a return in line with the growth in earnings. If earnings don't grow, the market's not going up."
The period of annual 20-percent-plus S&P 500 gains is over, he said, but with the index currently trading at a multiple of 15 to 16, it could get back to 2,100 next year.