Billionaire Warren Buffett said Monday he's not concerned about the recent decline in IBM, in which he's a large shareholder.
The stock closed Friday at $155 a share, after the tech giant reported quarterly revenue that fell short of estimates. It has dropped about 10 percent since July 20.
Buffett told CNBC's "Squawk Box" that his ownership cost of IBM stock is around $170 a share.
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"I love it when it goes down. It means the company buys stock cheap, the Berkshire Hathaway chairman and CEO said.
In perhaps a signal he's also been a buyer, he added, "It means if I want to buy stock, and you can look at our 13F in a few days ... I get to buy it cheaper." It's worth noting that he did not say definitively either way whether he's a buyer.
Shares of IBM were slightly higher Monday.
But he stressed, "I'm not a seller" of IBM—saying he does want the stock to eventually head higher, maybe "five or 10 years from now."
As of March 31—as reported in Berkshire Hathaway's 13-F filing on May 15—his company held an 8.12 percent stake, 79.57 million shares. Berkshire is IBM's largest shareholder, with almost 20 million more shares than the next-biggest investor.
He bought an additional 2.6 million shares in the first quarter, valuing his overall holdings in IBM at $12.3 billion as of Friday's close.
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