Warren Buffett's Berkshire Hathaway agrees to buy insurer Alleghany for nearly $12 billion

• Berkshire Hathaway agreed to buy insurer Alleghany in an all-cash deal worth $11.6 billion.
• The conglomerate offered $848 per share for Alleghany, a 25% premium to Friday's closing price.

Berkshire Hathaway announced Monday it's agreed to acquire insurer Alleghany Corporation in an all-cash deal for about $12 billion that would boost billionaire investor Warren Buffett's insurance arm.

The conglomerate offered $848.02 for each share of Alleghany, a level that is 25% higher than the investment-holding firm's closing price on Friday. Its shares rose as much as 25% in Monday's pre-market session.

Alleghany, founded in 1929 by American railroad barons Oris and Mantis Van Sweringen, has a similar business model to Berkshire, which invests and holds a diverse range of businesses, including insurance firm Geico. Through its subsidiaries, the company hunts for opportunities in the property, casualty reinsurance, and insurance sectors.

"Berkshire will be the perfect permanent home for Alleghany, a company that I have closely observed for 60 years," Buffett said in a statement.

"Throughout 85 years the Kirby family has created a business that has many similarities to Berkshire Hathaway. I am particularly delighted that I will once again work together with my long-time friend, Joe Brandon."

Jefferson Kirby is the chair of Alleghany's board — and controls 2.5% of its common shares — while Joe Brandon is the insurer's president and chief executive officer.

Alleghany acquired global reinsurer Transatlantic Holdings for $3.4 billion in 2011. It also owns companies involved in a range of businesses including manufacturing toys like Peppa Pig, fabricating steel for industrial projects like sports stadiums to office-building complexes, and producing funeral parlor products.

It reported full-year revenue for 2021 rose 35% to $12 billion in 2021 as the company rebounded from the pandemic.

Author Lawrence Cunningham has compared Alleghany's business to Buffett's own model in his book "Margin of Trust," saying its operating principles are similar to Berkshire's "Owner's Manual" for its shareholders.

Berkshire said the deal includes a 25-day "go-shop" period that allows Alleghany to explore other bids for its business.

The deal is expected to close in the fourth quarter this year, and is subject to conditions, such as shareholder and regulatory approval. Once the deal has closed, Alleghany will continue to operate as an independent unit of the conglomerate.

Buffett, who has a history of successful value-based investing, most recently boosted his stake in energy company Occidental Petroleum. His latest purchase of about $7 billion worth of Occidental shares takes his stake to 15%.

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