Octogenarian billionaire Warren Buffett assured shareholders on Saturday that his Berkshire Hathaway empire, with holdings in major American firms, is ready for him and his longtime partner Charlie Munger, 96, to go.

But he did not name a successor.

Dubbed the "Oracle of Omaha," Buffett is known for his track record of brilliant investing but also for his folksy and humble persona, as well as his philanthropy.

"Charlie and I long ago entered the urgent zone," Buffett, 89, quipped in his annual letter to shareholders.

"That's not exactly great news for us. But Berkshire shareholders need not worry: Your company is 100 percent prepared for our departure."

Buffett, one of the world's richest men, cited several factors for his optimism.

Warren Buffett is known for his track record of brilliant investing but also for his folksy and humble persona, as well as his philanthropy.
Warren Buffett is known for his track record of brilliant investing but also for his folksy and humble persona, as well as his philanthropy. AFP / Johannes EISELE

"We possess skilled and devoted top managers for whom running Berkshire is far more than simply having a high-paying and/or prestigious job," he said, adding that its assets are deployed in "an extraordinary variety" of businesses.

At an annual shareholders' meeting last May, Buffett gave a clue as to who might follow him, when he said that Gregory Able and Ajit Jain would in the near future join him and Munger on the stage to answer questions.

Able, 57, and Jain, 67, had been promoted to the board of directors the previous year.

"Charlie and I have very pragmatic reasons for wanting to assure Berkshire's prosperity in the years following our exit," Buffett said in the letter published Saturday.

"The Mungers have Berkshire holdings that dwarf any of the family's other investments, and I have a full 99 percent of my net worth lodged in Berkshire stock."

Buffett added that he has never sold any shares -- and has no plans to do so.

Charlie Munger, 96, has been Warren Buffett's longtime partner
Charlie Munger, 96, has been Warren Buffett's longtime partner AFP / Johannes EISELE

Berkshire Hathaway has holdings in companies including American Express, JPMorgan Chase, Goldman Sachs, Apple and Coca-Cola. It is also active in sectors like insurance, through Geico; rail, with BNSF; and energy, via PacifiCorp.

It also has a stake in Amazon.

Along with Microsoft co-founder Bill Gates and his wife Melinda Gates, Buffett in 2010 launched the "Giving Pledge," in which billionaires promise to give at least half their wealth to philanthropic causes.

Last year Buffett announced that he had donated $3.6 billion worth of Berkshire Hathaway stock to the Bill & Melinda Gates Foundation and four other charities, meaning that he had given a total of about $34 billion to the five foundations.

He and Gates have expressed concern about America's severe wealth inequality.

Forbes said in its rankings last year that Buffett was worth $82.5 billion.

He continues to live in a relatively modest house about 10 minutes outside downtown Omaha, Nebraska that he bought in 1958.

In the letter, Buffett underlined that his will directs executors and trustees "not to sell any Berkshire shares."

The will orders that each year a portion of his Class A shares be converted to Class B shares that would then be distributed "to various foundations," Buffett said.

"I estimate that it will take 12 to 15 years for the entirety of the Berkshire shares I hold at my death to move into the market."

Buffet reported that Berkshire Hathaway's operating earnings were largely unchanged in 2019.

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