Berkshire Hathaway Takes a 2.49% Stake in Tokio Marine for About $1.8 Billion in a 10-Year Reinsurance and Investment Partnership

One of the world's best-known investors has taken a stake in Japan's largest property and casualty insurer. On Monday, March 23, 2026, Berkshire Hathaway announced that its subsidiary National Indemnity Company would acquire a 2.49% strategic stake in Tokio Marine Holdings for ¥287.4 billion, about $1.8 billion. The deal comes with a ten-year partnership covering reinsurance and joint investment activity. This article is based on Insurance Journal's report of the announcement. An earlier version said Berkshire's chief executive Greg Abel confirmed at the annual meeting in May that the shares would be held long-term, and called the arrangement a whole-account quota share. Neither statement appears in the report reviewed, so they have been removed.

The terms of the investment are specific. According to the report, Berkshire will buy about $1.8 billion of Tokio Marine's treasury stock, meaning shares the company already holds. Tokio Marine will then buy back the same dollar amount of its existing shares on the market. In effect, the new shares go to Berkshire while the company reduces the number of shares outstanding elsewhere, so the total number held by the public falls. Any further purchases by Berkshire would likely be made on the open market. Berkshire has agreed not to exceed a 9.9% stake without the approval of Tokio Marine's board, a standard protection for the company against an unwelcome increase in influence.

The partnership has several parts. The two companies will collaborate on reinsurance and on global investments, including mergers and acquisitions. Reinsurance is insurance for insurers, in which a company passes part of its risk to another in return for a share of the premium. Tokio Marine can use National Indemnity as a reinsurance option for any type of insurance, without restriction. A Tokio Marine spokesman, Mitsuhiro Izu, said that Berkshire proposed the partnership. The agreement runs for ten years, and for the first five years neither company may enter into similar agreements with competitors, a form of exclusivity that locks in the relationship for a significant period.

Who are the partners? Tokio Marine is Japan's largest property and casualty insurer, with a large international business built through acquisitions over the past two decades. Berkshire Hathaway owns National Indemnity and GEICO, and is among the largest reinsurers in the world. The report notes that Berkshire has been expanding in Japan. Under Warren Buffett it invested in five large Japanese trading houses and said it intended to raise those stakes over time. Late last year Berkshire raised just over ¥210 billion, about $1.3 billion, through yen-denominated bonds, its first Japanese bond issue since 2019. Buffett retired as chief executive at the end of 2025, and Greg Abel succeeded him. Seen against that background, the Tokio Marine investment extends an existing strategy into financial services.

What is in it for each side? For Tokio Marine, the benefits are access to reinsurance capacity from a counterparty with very large capital, a long-term shareholder at a time when many Japanese companies are trying to improve capital efficiency and shareholder returns, and a partner for international acquisitions. The share buyback that accompanies the transaction supports earnings per share. For Berkshire, the stake gives exposure to a leading insurer in a market where interest rates are rising from low levels and where the yen has been weak, and it creates a flow of reinsurance business. The report does not give financial projections for either company, and none should be inferred.

An analyst quoted in the report, Ikuo Mitsui of Aizawa Securities, said the partnership with Berkshire is likely to provide an advantage. That is one opinion, and the report does not say what advantage he expected in the long run.

There are questions that the report does not answer. It does not specify the reinsurance volumes that would be ceded to National Indemnity, the price, or how the joint investment collaboration would work in practice. Nor does it say whether Berkshire has any right to a seat on the board. The 9.9% ceiling and the five-year exclusivity are the main protections described, and observers will watch for details in Tokio Marine's own disclosures and in Berkshire's annual report.

For policyholders in Japan or elsewhere, the direct effects are limited. The arrangement concerns the capital and risk-transfer structure of the insurer and not the terms of customer policies. Indirectly, additional reinsurance capacity could help Tokio Marine write business in markets where catastrophe risk is high, which can support availability of cover.

Investors reading about the deal should also keep in mind that a 2.49% stake does not give Berkshire control, and that the benefits depend on how the reinsurance relationship and joint investments develop over the decade. Neither company has published a target for the business to be ceded, so the practical value is hard to measure from the announcement alone.

More broadly, the deal is part of a trend of cross-border cooperation among large insurers, in which capital and underwriting capabilities are shared through minority stakes and long-term contracts rather than full takeovers. Whether the partnership delivers measurable benefits will become clear in the results Tokio Marine and Berkshire report in coming years.