Apple and Tesla stocks rose sharply on Monday, the first day of their stock splits.
Apple was up 3.4% and was the top performing component in the Dow Jones Industrial Average. Tesla jumped 12.6%.
Monday's gains were the latest in a string of strong performances since the companies' stock splits were announced.
Apple said on July 30th that its board had approved a 4-for-1 stock split. Since then, the stock has risen more than 34%. Tesla has soared more than 80% since announcing a 5-for-1 stock split on Aug. 11.
However, billionaire investor Leon Cooperman said Monday that ramp-ups due to stock split announcements are a problematic sign for the market.
"Look at Tesla and Apple: Everyone understands that divisions create no value," the founder of Omega Advisors told CNBC's "Squawk Box". "My father once told me that if you gave me five singles for a $ 5 bill, I wouldn't be any better."
Apple and Tesla's profits on Monday were due to high volume as smaller traders can purchase shares of both companies at a much lower price than Friday.
Apple traded 223.4 million shares, roughly 25% more than the stock's 30-day volume average of 178.588 million. Tesla shares traded hands 115.6 million times, well above the 30-day average of 73.369 million.
This year, smaller retailers have been more actively involved in the market, as the commission-free online brokerage Robinhood is becoming increasingly popular. However, Cooperman sees this as a potential sign of overheating.
"I see signs of euphoria in the market: the IPO-SPAC market is one [and] the craziness in many stocks that the Robinhood crowd has grown accustomed to," Cooperman said. "You see a Kodak go from $ 1.50 to $ 60 and from $ 60 to $ 6 in a very short time … and if you look at that, it's the Robinhood crowd that picks it up."
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