The billionaire investor said Berkshire Hathaway Inc. completely exited its stakes in the four major U.S. airlines. The sales of shares of Delta Air Lines Inc., Southwest Airlines Co., American Airlines Group Inc. and United Airlines Holdings Inc. made up most of the company’s $6.5 billion in equity sales in April.

During his live-streamed annual meeting, Buffett said the business has fundamentally changed following the economic fallout from the coronavirus pandemic. He declined to blame the performance of the airline CEOs, adding that he doesn’t envy their jobs, especially in a period like this.

“The world changed for airlines and I wish them well,” Buffett said Saturday in a webcast. He clarified that he made the decision and that he lost money on his investments. “That was my mistake.”

Buffett’s had a complicated relationship with the airline industry over the years. After a troublesome investment in USAir, Buffett joked that he would call an 800 number to declare he was an “air-o-holic” if he ever got the urge to invest in airlines again.

Then in 2016, Berkshire dove into the industry again, amassing stakes in the four largest airlines. His renewed faith in the industry prompted speculation that he might one day own one of the carriers.

But now, he’s cut those investments again. Berkshire disclosed in April that it had at least trimmed its Delta and Southwest stakes, both of which had previously been above a 10% ownership level.

“The airline business — and I may be wrong and I hope I’m wrong — but I think it’s changed in a very major way,” Buffett said. “The future is much less clear to me.”

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