Investment Bank

An investment bank is typically a private company that provides various financial-related and other services to individuals, corporations, and governments such as raising financial capital by underwriting or acting as the client's agent in the issuance of securities. An investment bank may also assist companies involved in mergers and acquisitions (M&A) and provide ancillary services such as market making, trading of derivatives and , and FICC services (fixed income instruments, currencies, and commodities).

Unlike commercial banks and retail banks, investment banks do not take deposits. From the passage of Glass–Steagall Act in 1933 until its repeal in 1999 by the Gramm–Leach–Bliley Act, the United States maintained a separation between investment banking and commercial banks. Other industrialized countries, including G7 countries, have historically not maintained such a separation. As part of the Dodd–Frank Wall Street Reform and Consumer Protection Act of 2010 (Dodd-Frank Act of 2010), the Volcker Rule asserts some institutional separations of investment banking services from commercial banking.

The two main lines of business in investment banking are called the sell side and the buy side. The "sell side" involves trading securities for cash or for other securities (e.g. facilitating transactions, market-making), or the promotion of securities (e.g. underwriting, research, etc.). The "buy side" involves the provision of advice to institutions that buy investment services. Private equity funds, mutual funds, life insurance companies, unit trusts, and hedge funds are the most common types of buy-side entities.

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