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Warren Buffett and value investing
Berkshire from 1965· Economist or figure
Fact, law or dataA rule, statute, definition or measured number.
Warren Buffett, born in Omaha in 1930, built Berkshire Hathaway into a roughly $1 trillion company by buying undervalued businesses to hold for decades.
See it on the Money & Finance map →How it works
He studied under Benjamin Graham, father of value investing: buy assets for less than their worth, with a margin of safety. In 1965 he took control of Berkshire, a failing textile mill, and turned it into a holding company for insurers (GEICO), the BNSF railroad, utilities and stakes in Coca-Cola, Apple and American Express. From 1965 to 2024 Berkshire's share price compounded about 20% a year, roughly double the S&P 500. Greg Abel succeeded him as CEO in January 2026.
Why it matters
He became the model for patient, business-focused investing, and his plain advice, including that most people should own a low-cost S&P 500 index fund, shaped generations of investors.
Think of it like
He buys companies the way a seasoned owner buys buildings: on durable cash flow, below replacement value, to hold for decades.
Legacy
His annual Berkshire shareholder letters, Berkshire's audited filings and biographies such as Alice Schroeder's The Snowball (2008). He won a 2008–2017 bet that an index fund would beat hedge funds.
Debates and risks
Whether Berkshire can keep beating the market at its size and without Buffett, and what it will do with its cash pile, over $340 billion in 2025.
Connections (4)
▸Warren Buffett and value investing recommends for most people Index funds and passive investingFact, law or data
The connection
Buffett, himself a famed stock picker, has long said most people should own a low-cost S&P 500 index fund. His will directs that 90% of the cash left for his wife go into one, with 10% in short-term government bonds. He also bet $1 million that an index fund would beat hedge funds over ten years, and won.
When and why
Berkshire Hathaway letters, especially the one for 2013; the bet with Protégé Partners ran 2008–2017, with proceeds going to Girls Inc. of Omaha.
How we know
His published letters; the S&P 500 fund gained about 126% over the bet versus about 36% for the hedge-fund picks.
Debates and risks
Buffett beat the market for decades; whether his record disproves efficient markets or is a rare, hard-to-identify exception is debated.
▸Warren Buffett and value investing called 'weapons of mass destruction' Options and other derivativesFact, law or data
The connection
In his 2002 letter Buffett called derivatives 'financial weapons of mass destruction', warning that hidden leverage and murky valuations could chain firms together in a crisis. He spoke from experience: unwinding General Re's derivatives book cost Berkshire about $400 million. Yet Berkshire also sold long-dated index put options it considered mispriced.
When and why
Berkshire Hathaway's letter for 2002, published in March 2003; the General Re Securities wind-down began in 2002 and ran for several years.
How we know
The letter text and Berkshire's annual reports, which disclose the Gen Re losses and its own put contracts.
Debates and risks
Whether AIG's 2008 collapse vindicated him, and how to square the warning with Berkshire's own large derivative bets, are still discussed.
▸Warren Buffett and value investing built Berkshire on the float of Insurance companies: pooling risk and investing premiumsFact, law or data
The connection
Insurers collect premiums now and pay claims later; the money held in between, called 'float', can be invested. Buffett bought National Indemnity in 1967, later GEICO and General Re, and invested their float in stocks and whole companies. When underwriting is profitable, float is better than a free loan, like holding tenants' security deposits for years.
When and why
Omaha: National Indemnity in 1967 for about $8.6 million, full ownership of GEICO in 1996, General Re in 1998. Float reached about $170 billion by 2024.
How we know
Buffett reports float every year in his shareholder letters, backed by Berkshire's audited filings.
Debates and risks
Whether the float model works as well under new CEO Greg Abel, and how larger catastrophe losses from wildfires and storms affect it.
▸Warren Buffett and value investing bought stakes in five trading houses on Tokyo Stock Exchange (Japan Exchange Group)Fact, law or data
The connection
On August 30, 2020, Berkshire Hathaway disclosed about 5% stakes in Itochu, Marubeni, Mitsubishi, Mitsui and Sumitomo, Japan's big trading houses. It raised them to about 10% each, funded partly with low-rate yen bonds. By end-2025 the five stakes were worth about $35 billion, against a cost of about $15 billion.
When and why
Tokyo, filings by Berkshire unit National Indemnity from 2020 to 2026; Buffett visited Japan in April 2023.
How we know
Japanese large-shareholding filings, Berkshire's annual reports and shareholder letters, and its yen-bond offering documents.
Debates and risks
Whether Berkshire's endorsement sparked Japan's revival or rode it, and how the stakes evolve after Buffett stepped down as CEO at the end of 2025.