Berkshire Hathaway is the investment company whose longtime chairman is Warren Buffett and which owns businesses such as GEICO and BNSF Railway.
Berkshire began as a New England textile manufacturer. Warren Buffett acquired shares in the 1960s and ultimately transformed the company into a diversified holding company rather than preserving textiles as its main business.
Its operations have included insurance, rail transport, utilities, energy, manufacturing, retail, and service businesses. GEICO is an insurance subsidiary, while BNSF Railway is one of the largest freight railroad networks in North America.
Berkshire is often described as a conglomerate, not a conventional mutual fund or bank. Its large public-stock portfolio attracts attention, but wholly owned operating companies and insurance operations are also central to its business model. Buffett has chaired Berkshire for decades.