Berkshire Hathaway Inc. (BRK.B)

Berkshire Hathaway is a holding company owning subsidiaries in many unrelated lines of business. The filing names the most important as the insurance businesses, written both directly and as reinsurance, a freight railroad, and a group of utility and energy businesses. Beyond those sit manufacturing, service and retailing companies. It is domiciled in Delaware with its head office in Omaha, Nebraska, and employed about 387,800 people worldwide at the end of 2025, roughly 80 percent of them in the United States.

How it is run

The filing states the management approach directly: the operating subsidiaries are managed on an unusually decentralised basis, with few centralised or integrated business functions. The filing places responsibility for major capital allocation decisions and investment activities, and for evaluating how the operating businesses perform, with the chief executive. Each subsidiary sets its own hiring and employment practices.

Insurance, and the float

The insurance subsidiaries write property and casualty and life and health risks worldwide, and employed about 42,600 people at the end of 2025. In direct insurance the insurer takes the risk from the person or organisation exposed to it; in reinsurance it takes a defined share of risk that another insurer has already assumed.

GEICO sells private passenger motor insurance direct to the customer. According to A.M. Best data for 2024 published in 2025, the five largest private passenger motor insurers held about 63.6 percent of the market by written premiums, with GEICO third at about 11.6 percent.

Berkshire Hathaway Primary Group is a collection of independently managed insurers. Nearly 90 percent of its net premiums written in 2025 were in the United States, and about 40 percent of that was written on a non-admitted basis, meaning excess and surplus lines, which face considerably less regulation of rates and policy wording. Inside it, the National Indemnity companies write commercial motor and general liability, Berkshire Hathaway Homestate writes workers' compensation, commercial motor and commercial property, and Berkshire Hathaway Specialty Insurance writes commercial property and casualty and executive and professional lines from Boston, with offices in Australia, Canada, New Zealand and across Asia and Europe.

On the reinsurance side, the National Indemnity group writes traditional and catastrophe reinsurance and takes a 20 percent quota share of Insurance Australia Group that runs to 31 December 2029. General Re writes global property and casualty reinsurance, directly in North America and internationally out of Cologne, and participates at Lloyd's through Syndicate 435; it also runs a global life and health reinsurance business. TransRe writes quota-share and excess-of-loss reinsurance, mostly through brokers. Retroactive reinsurance contracts cover other insurers for adverse development on claims from loss events that have already happened.

The money behind all this comes from two places: shareholder capital, and float, which the filing defines as the approximate net policyholder funds generated through underwriting and held for investment. Float rose from about $138 billion at the end of 2020 to about $176 billion at the end of 2025. Berkshire notes that its investment portfolios have historically held a much greater proportion of equities than is customary in the insurance industry.

The railroad

BNSF, based in Fort Worth, runs one of the largest freight rail systems in North America, with about 35,000 employees at the end of 2025, roughly 30,000 of them union members. It serves the Midwest, Pacific Northwest, Western, Southwestern and Southeastern regions and certain ports, reaching parts of Canada and Mexico, and works with about 200 shortline railroads to serve smaller markets. Freight revenue falls into consumer products, industrial products, agricultural and energy products, and coal. Its main rail competitor in the West is Union Pacific.

Energy and utilities

Berkshire Hathaway Energy is a holding company in Iowa employing about 24,000 people. It owns four regulated US utilities serving about 5.4 million retail customers, and five interstate natural gas pipeline companies operating about 20,900 miles of pipeline with a design capacity of about 21.6 billion cubic feet a day. Outside that it holds electric transmission and distribution in Great Britain and Canada, a portfolio of mostly renewable independent power projects, and a 75 percent interest in a liquefied natural gas export, import and storage facility. It also owns a residential estate agency and franchises a large network of others.

Everything else

Manufacturing splits three ways. Industrial products covers aerospace and power generation components, specialty chemicals and metal cutting tools, through Precision Castparts, Lubrizol, IMC and Marmon among others. Building products covers prefabricated and site-built homes, flooring, insulation, roofing, paint and bricks, through Clayton, Shaw, Johns Manville, MiTek, Benjamin Moore and Acme. Consumer products covers recreational vehicles, apparel and footwear.

The service businesses include shared aircraft ownership and aviation training, electronic component distribution, quick service restaurant franchising, transportation equipment and furniture leasing, third-party logistics for the petroleum and chemical industries, distribution of electronic news and regulatory filings, facilities engineering, and a television station in Miami. McLane, which provides wholesale distribution in all 50 states to customers including convenience stores and discount retailers, is reported as a separate segment. Retailing runs from three jewellery chains through confectionery, kitchen tools, party and school supplies, a German motorcycle accessories retailer, car dealerships, home furnishings and the Pilot travel centre network.

From Berkshire Hathaway's annual report on Form 10-K for the year ended 31 December 2025. The filing