Berkshire Hathaway is a holding company with a wide array of subsidiaries engaged in diverse activities. The firm's core business segment is insurance, run primarily through Geico, Berkshire Hathaway Reinsurance Group and Berkshire Hathaway Primary Group. Berkshire has used the excess cash thrown off from these and its other operations over the years to acquire Burlington Northern Santa Fe (railroad), Berkshire Hathaway Energy (utilities and energy distributors), and the firms that make up its manufacturing, service, and retailing operations (which include five of Berkshire's largest noninsurance pretax earnings generators: Precision Castparts, Lubrizol, Clayton Homes, Marmon and IMC/ISCAR). The conglomerate is unique in that it is run on a completely decentralized basis.

JPMorgan Chase is one of the largest and most complex financial institutions in the United States, with more than $2.5 trillion in assets. It is organized into four major segments--consumer and community banking, corporate and investment banking, commercial banking, and asset and wealth management. JPMorgan operates, and is subject to regulation, in multiple countries.

Bank of America is one of the largest financial institutions in the United States, with more than $2.3 trillion in assets. It is organized into four major segments: consumer banking, global wealth and investment management, global banking, and global markets. Bank of America's consumer-facing lines of business include its network of branches and deposit-gathering operations, home mortgage lending, vehicle lending, credit and debit cards, and small-business services. The company's Merrill Lynch operations provide brokerage and wealth management services, as does U.S. Trust private bank. Wholesale lines of business include investment banking, corporate and commercial real estate lending, and capital markets operations. Bank of America has operations in several countries.

Wells Fargo is one of the largest banks in the United States, with approximately $1.9 trillion in balance sheet assets. The company is split into three segments for reporting purposes: community banking; wholesale banking; and wealth and investment management. The community banking segment serves consumers and small businesses with products including deposit accounts, credit and debit cards, and student, mortgage, and home equity loans. Wholesale banking includes corporate and commercial real estate lending, asset-based lending and trade financing, merchant services, and capital markets businesses. Wealth and investment management includes advisory, brokerage, retirement, and trust services. The bulk of Wells' lending takes place in the U.S.

Citigroup is a global financial services company doing business in more than 100 countries and jurisdictions. Citigroup's operations are organized into two primary segments, the global consumer banking segment, which provides basic branch banking around the world, and the institutional clients group, which provides large customers around the globe with investment banking, cash management, and other products and services.

American Express is a global financial institution, operating in about 130 countries, that provides consumers and businesses charge and credit card payment products. The company operates a highly profitable merchant payment network. Since 2018, the company has operated in three segments: global consumer services, global commercial services, and global merchant and network services. In addition to payment products, the company's commercial business offers expense management tools, consulting services, and business loans.

As a diversified financial-services provider, U.S. Bancorp is the nation's fifth-largest bank with branches in well over 20 states, primarily in the western and midwestern United States. The bank offers many services, including retail banking, commercial banking, trust and wealth services, credit cards, mortgages, and other payments capabilities.

Goldman Sachs is a global investment banking firm whose activities are organized into investment banking, institutional client services, investing and lending, and investment management segments. Approximately 60% of the company's net revenue is generated in the Americas, 15% in Asia, and 25% in Europe, the Middle East, and Africa. In 2008, Goldman reorganized itself as a financial holding company regulated by the Federal Reserve System.

Based in Chicago, CME Group operates exchanges that allow investors, suppliers, and businesses to trade futures and derivatives based on interest rates, equity indexes, foreign currencies, energy, metals, and commodities. The CME was founded in 1898 and in 2002 completed its initial public offering. Since then, CME Group has consolidated part of the industry by merging with crosstown rival CBOT Holdings (2007) before acquiring Nymex Holdings in 2008. In addition, CME has a 27% stake in S&P/Dow Jones Indexes LLC along with an exclusive license to trade and clear S&P futures contracts.

PNC Financial Services Group is a diversified financial services company offering retail banking, corporate and institutional banking, asset management, and residential mortgage banking. PNC has 2,600 branches in 19 states and the District of Columbia and is the sixth- largest U.S. bank by assets.