Apple stock closed at a record Friday, surpassing its previous high of $183.50 — pushed up by news that Warren Buffett's Berkshire Hathaway bought 75 million shares in the first quarter.

The stock closed at $183.83, and is now roughly $20 per share short of a $1 trillion market cap.

Buffett is in Omaha, Nebraska, for the annual Berkshire Hathaway shareholders meeting, and he hasn't been shy about his bull case for Apple.

The legendary investor revealed his company's massive stake in Apple and said obsessing over iPhone X sales in the near term "totally misses the point" on the stock. Buffett's comments drove Apple ahead of the rest of the tech sector and overall market.

The Dow dropped 100 points after the open; tech giants Amazon, Alphabet, Netflix and Facebook all started trading in the red — but Apple was nearly 4 percent up at its peak.

"I don't think he's done. I think the numbers of the investment in Apple are going to go higher and maybe even significantly higher," said David Rolfe, CIO of Wedgewood Partners, which counts Berkshire and Apple as its two largest holdings.

Apple currently accounts for about a quarter of Berkshire's portfolio, Rolfe told CNBC's "Squawk on the Street," but he wouldn't be surprised to see that increase to a third or even half of the portfolio.

Apple CEO Tim Cook said the company is "thrilled" to have Buffett and Berkshire as a major investor.

"On a personal level, I've always greatly admired Warren and have always been grateful for his insight and advice," Cook said in a statement.

Buffett told CNBC he'd been buying a lot of stock in the first quarter, but not across the board. He revealed Berkshire had sold completely out of IBM and said he is not looking to buy General Electric.

He also spoke to broader economic growth and commented on a rare activist move to block the board nominations at building materials company USG.