Berkshire Hathaway Inc. Vice Chairman Charlie Munger dropped the biggest hint yet that the conglomerate's future chief executive could either be Ajit Jain, the head of its reinsurance business, or Greg Abel, who runs its energy business.

In a letter to shareholders sharing his thoughts about the past and future of Berkshire Hathaway, Munger said that Berkshire would remain a “better-than-normal” company with its current structure even if chairman and CEO Warren Buffett left the company tomorrow, his successors were persons of only moderate ability and Berkshire never bought another large business again.

"But, under this Buffett-soon-leaves assumption, his successors would not be 'of only moderate ability.' For instance, Ajit Jain and Greg Abel are proven performers who would probably be under-described as "world-class," Munger wrote. He added that in some ways, "each is a better business executive than Buffett."

Munger also said that neither of the two executives is likely to leave Berkshire Hathaway or want to change the company’s structure in a big way.

Munger appeared to be making a hypothetical case in naming the two men. But analysts and Berkshire shareholders have long speculated that  Jain, 63, is the most likely candidate to succeed Buffett as CEO. Abel, who is about a decade younger, has been another name on investors’ shortlists.

Both are longtime Berkshire executives.

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