Billionaire Warren Buffett had been bothered for years by how the Bill & Melinda Gates Foundation was being run, according to a New York Times report on Sunday.

The Berkshire Hathaway CEO, who recently said the philanthropy will stop getting his money after he dies, had grown to view the foundation as bloated with inflated operating costs, sources told the Times.

Buffett also told staffers that the Gates Foundation had become complacent and had less appetite for risks that could boost the effectiveness of its giving, the report said.

The Gates Foundation didn’t provide an immediate comment, and Berkshire Hathaway didn’t respond to requests for comment.

Buffett had been a top donor to the Gates Foundation, giving more than $39 billion between 2006 and 2023. Over the years, Buffett and Bill Gates developed a close friendship. And in 2021, Buffett said his goals “are 100% in sync with those of the foundation.”

The Times noted he attached three conditions to his money: either Bill Gates or Melinda French Gates had to remain active in the foundation, Buffett’s contributions had to be counted as charity versus gifts, and the value of his annual contributions had to be given away within a year, not including the 5% that’s already required of philanthropies.

Meanwhile, Buffett had made clear to the Gates Foundation that it shouldn’t count on continuing to receive his money over the long term, given that he was aging and his pledges would only encompass his lifetime, sources told the Times.

According to his will, his remaining wealth will go to a charitable trust overseen by his three children, who must decide unanimously how the money will be spent.

In a separate interview with the Times last month, French Gates, who stepped down from the foundation in May, said she wasn’t surprised by Buffett’s decision, adding that she was aware he was making it.

“The other thing that’s really important to say is he has given an enormous sum through the Bill and Melinda Gates Foundation,” she said. “So I think this has just been a good evolution to his thinking on how he wants to do his giving.”

While it’s technically still possible the Gates Foundation could get more of Buffett’s wealth after he dies, sources told the Times that Buffett’s children all agree that none of the remaining Berkshire Hathaway shares to be given away will go to the Gates Foundation.

Buffett himself was explicit about what would happen.

“The Gates Foundation has no money coming after my death,” he told the Wall Street Journal in June.