Prime brokerage is the generic term for a bundled package of services offered by large financial institutions (including investment banks and broker-dealers) to hedge funds, commonly including financing and securities lending to facilitate leveraged trading strategies. Prime brokers also typically provide centralized clearing and settlement and consolidated reporting for client positions.

Prime brokers earn revenue primarily through spreads on financing and securities lending and may also earn fees for clearing and other services. In some jurisdictions and structures, prime brokers may have rights of rehypothecation over client collateral, which can support the economics of financing and securities-lending activities.

Each client in the market of a prime broker will have certain technological needs related to the management of its portfolio. These can be as simple as daily statements or as complicated as real-time portfolio reporting, and the client must work closely with the prime broker to ensure that its needs are met. Certain prime brokers offer more specialized services to certain clients.

For example, a prime broker may also be in the business of leasing office space to hedge funds, as well as including on-site services as part of the arrangement. Risk management and consulting services may be among these, especially if the hedge fund has just started operations.

The basic services offered by a prime broker give a money manager the ability to trade with multiple brokerage houses while maintaining, in a centralized master account at their prime broker, all of the hedge fund's cash and securities. Additionally, the prime broker offers stock loan services, portfolio reporting, consolidated cash management and other services. Fundamentally, the advent of the prime broker freed the money manager from the more time consuming and expensive aspects of running a fund.

These services worked because they also allowed the money manager to maintain relationships with multiple brokerage houses for IPO allocations, research, best execution, conference access and other products.

The concept and term "prime brokerage" is generally attributed to the U.S. broker-dealer Furman Selz in the late 1970s. However, the first hedge fund operation is attributed to Alfred Winslow Jones in 1949. In the pre-prime brokerage marketplace, portfolio management was a significant challenge; money managers had to keep track of all of their own trades, consolidate their positions and calculate their performance regardless of which brokerage firms executed those trades or maintained those positions.

The concept was immediately seen to be successful, and was quickly copied by the dominant bulge bracket brokerage firms such as Morgan Stanley, Bear Stearns, Merrill Lynch, Credit Suisse, Citigroup, and Goldman Sachs. At this nascent stage, hedge funds were much smaller than they are today and were mostly U.S. domestic long/short equity funds. The first non-U.S. prime brokerage business was created by Merrill Lynch's London office in the late 1980s. After the 2008 financial crisis, new entrants came to the market with custody-based prime brokerage offerings.

Through the 1980s and 1990s, prime brokerage was largely an equities-based product, although various prime brokers did supplement their core equities capabilities with basic bond clearing and custody. In addition, prime brokers supplemented their operational function by providing portfolio reporting; initially by messenger, then by fax and today over the web. Over the years, prime brokers have expanded their product and service offerings to include some or all of the full range of fixed income and derivative products, as well as foreign exchange and futures products.

As hedge funds proliferated globally through the 1990s and the 2000s, prime brokerage became an increasingly competitive field and an important contributor to the overall profitability of the investment banking business. As of 2006, the most successful investment banks each report over US$2 billion in annual revenue directly attributed to their prime brokerage operations (source: 2006 annual reports of Morgan Stanley and Goldman Sachs).

The 2008 financial crisis led to numerous brokers and banks restructuring, and customers, worried about their credit risk to their prime brokers, sought to diversify their counter-party exposure away from many of their historic sole or dual prime broker relationships.

Restructuring transactions in 2008 included the absorption of Bear Stearns into JP Morgan, the acquisition of the assets of Lehman Brothers in the US by Barclays, the acquisition of Merrill Lynch by Bank of America, and the acquisition of certain Lehman Brothers assets in Europe and Asia by Nomura.

Counter-party diversification saw the largest flows of client assets out of Morgan Stanley and Goldman Sachs (the two firms who had historically had the largest share of the business, and therefore had the most exposure to the diversification process), and into firms which were perceived, at the time, to be the most creditworthy. The banks which captured these flows to the greatest degree were Credit Suisse, JP Morgan, and Deutsche Bank.

During these market changes, HSBC launched a prime brokerage business in 2009 called "HSBC Prime Services", which built its prime brokerage platform out of its custody business.