As the executive tapped to one day run Berkshire Hathaway’s BRK.B -0.52%decrease; red down pointing triangle insurance business, the engine that has powered Warren Buffett’s conglomerate for decades, Charlie Shamieh will be entrusted to navigate any number of disasters and calamities.
He’s had a lot of practice.

In the early 2000s, Shamieh helped reinsurer Munich Re contend with a crippling ratings downgrade. He then joined American International Group shortly before its near-collapse during the 2008-09 financial crisis, and stayed through its turnaround. And as a child, the Lebanon-born Shamieh had lived through war and civil unrest.

Now the 59-year-old Gen Re chairman is Berkshire’s choice to succeed Ajit Jain whenever the 74-year-old insurance mastermind decides to retire, The Wall Street Journal reported earlier this month.  Jain hasn’t indicated how long he plans to stay in the role, and it is possible that, by the time he is ready to retire, Berkshire will have to settle on a different successor.

It is a huge job no matter who fills it, and not just because the company’s insurance operations oversee more than half a trillion dollars in assets.

Every year, the business produces billions of dollars in cash that can be deployed to buy companies or individual stocks. In short, it has made Berkshire what it is today.  But challenges abound. Property insurers are navigating historic change and unpredictability. Claims for wildfires, severe thunderstorms and floods hit a record in 2025. At the same time, households face growing difficulty shouldering rising home insurance costs.

For those reasons, Berkshire watchers (and even Buffett himself) have argued that getting Jain’s replacement right was just as important as finding the best chief executive.

Berkshire insurance premiums left over after payouts and expenses Source:  Berkshire filings ReinsuranceGeicoOther  insurance2005'10'15'20'25-6-4-202468$10billion.

A known quantity in the insurance world, Shamieh isn’t quite a household name among Berkshire’s many fans and shareholders. For most of them, hearing “what Charlie thinks” is likely to conjure memories of Charlie Munger, Buffett’s longtime business partner who died in 2023.

Jain brought Shamieh to Berkshire’s reinsurance arm, Gen Re, in 2018.  But not before weighing whether the new hire’s arrival might portend trouble ahead given Shamieh’s track record for being at companies just as they confronted an existential crisis, Jain would later joke, according to the latest edition of Robert Miles’s book, “The Warren Buffett CEO.”

“Things weren’t collapsed.  I was used to chaos, and this wasn’t chaotic,” Shamieh said of joining Gen Re in the book.

The past eight years have been a relatively smooth ride.  A November report from insurance ratings firm AM Best showed Gen Re’s premiums written and financial cushion had both grown over the previous five years. Analysts have praised the reinsurer for resisting the temptation to add new business at the expense of profits.

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Like his bosses–Jain and Berkshire’s new CEO, Greg Abel–Shamieh cuts an unassuming and composed figure. He speaks softly, with a lilt he picked up when his family moved to Australia from Lebanon.

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“He was certainly calm under pressure,” said Thomas Russo, former general counsel at AIG. “Berkshire really made a great decision. Ajit is something special, but everyone is special in their own way.”

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Former colleagues at AIG describe Shamieh as a serious and hands-on manager. He is generous with compliments but expects his employees to earn them, they say.

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“He’s an intellectually demanding person to work for,” said Richard Brassington, who worked for Shamieh from 2012 to 2015.

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He works long hours.  On some mornings, Shamieh was known to send more than a dozen emails to colleagues before 6 a.m. 

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Shamieh’s first language is Arabic. His relatives on his father’s side were Palestinian refugees who fled amid territorial claims and political unrest, according to Miles’s book.

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Shamieh became an Australian citizen when he was seven. His family boarded a flight from Beirut to Sydney, sponsored by his aunt Janette, who had fled to the country earlier. He celebrated his birthday onboard. Flight attendants gave Shamieh stuffed animals and sang “Happy Birthday.”

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As a schoolboy, he discovered a talent for math and English, eventually enrolling at Macquarie University to study actuarial science at a mentor’s suggestion. He learned about probability, risk and statistics, skills that proved handy through stints at consulting firms Mercer and Oliver Wyman and, eventually, at insurers.

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Doug Dachille, former chief investment officer at AIG and Shamieh’s former boss, said he began working with Shamieh after then-AIG CEO Peter Hancock recommended that Shamieh serve as head of a so-called legacy unit, aimed at winding down business the insurance giant no longer wanted on its books.

 

“He’s inquisitive, he’s smart, he doesn’t get intimidated,” said Dachille. “When Charlie came into my office, within the first five minutes, I knew I had a rock star working for me.”

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The selection of Shamieh as Jain’s successor is a nod to the core role reinsurance plays in Berkshire’s operations. While only about a third of the premiums Berkshire collects come from reinsurance, the business stands alone among its peers for its appetite for complex reinsurance megadeals. 

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Shamieh’s post as Gen Re chairman has also given him sweeping exposure to many areas of the global insurance landscape. The company reinsures both property and casualty and life and health insurance policies, and does business in more than 20 countries. It accounted for 60% of Berkshire’s reinsurance premiums as of 2005, before the company stopped reporting Gen Re separately from its larger reinsurance business.

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As private-equity firms are pushing into insurance, he has pointedly defended Berkshire’s ultrasafe capital-heavy approach, saying in a 2021 video celebrating Gen Re’s 100th anniversary, “private equity is interested in medium-term not long-term.” 

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Shamieh is also clear-eyed about the challenges of filling Jain’s shoes. He told Miles, the author, that Berkshire’s stock price could drop whenever Jain announces his retirement, and that shareholders shouldn’t expect him to be a copycat.

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“I’ve tried to learn as much as I can from Ajit,” Shamieh told Miles. “I just hope I can do a fraction of what he has been able to do for Berkshire.”