Warren Buffett said on Saturday he bought more IBM stock for Berkshire Hathaway in the first quarter, but didn't specify by how much.
In a conversation with CNBC's Becky Quick ahead of today's shareholders meeting in Omaha, Buffett told her the exact numbers will be in the company's SEC filing revealing its stock holdings as of the end of March. That filing is due around the middle of this month.
At the beginning of February this year, IBM shares fell as low as $149.52 each, apparently giving Buffett a buying opportunity.
With the stock now trading near $174, IBM is up 8.2 percent since the end of the first quarter on March 31.
As of December 31, Berkshire reported holding 76,971,817 shares. That stake would be worth almost $13.4 billion at Friday's closing price.
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You can see all of Berkshire's U.S. stock holdings, as listed in the latest SEC filing, by going to CNBC.com's Berkshire Hathaway Portfolio Tracker.
Buffett first revealed in a November, 2011 CNBC interview that he had been building an IBM stake then worth $10.7 billion. The initial series of purchases, mostly between March and September of that year, were made at an average price of $170 per share.
—By CNBC's Alex Crippen. Follow him on Twitter: