Billionaire Warren Buffett defended his growing stake in IBM (NYSE: IBM) over the weekend and again on Monday, saying he is confident in Big Blue’s future.

Meanwhile, at the annual Berkshire Hathaway annual meeting in Omaha, Neb., IBM Chair and CEO Ginny Rometty emphasized the importance of its Watson supercomputer efforts to the company’s future.

Buffett’s Berkshire Hathaway added to its stake in the technology firm earlier this year. He appeared on CNBC Monday morning after answering shareholder questions.

“I bought it because I thought we were getting our money’s worth,” he told CNBC.

Buffett said he believes that IBM will be making more money 10 years from now than it does today, and IBM is repurchasing its stock aggressively so Berkshire’s share of the company’s profits will grow over time.

Berkshire owns about 9 percent of IBM’s stock now.

Buffett says he thinks IBM will fare well in cloud computing and corporate services because of the level of security it offers with its products.

IBM displayed the capabilities of its Watson program at Berkshire’s meeting on Saturday.

“It’s a service, so it ramps up over time by it’s nature,” Rometty told CNBC’s Becky Quick. “This will be a play for the long run.”

Watson program is crucial to IBM’s future, she added, so the decision was made not to spin it off.

“Could you have sold it? Would you have want to sell pieces of it as a product? To me, that would have been a short-term bump in revenue. But that’s what it is. It’s a long-term play,” she said.

​Read more from Rometty on Watson at:

IBM employs several thousand people in RTP and across North Carolina.