securities
A security is a tradable financial asset. The term commonly refers to any form of financial instrument, but its legal definition varies by jurisdiction. In some countries and languages people commonly use the term "security" to refer to any for ...
institutional investors
An institutional investor is an entity which pools money to purchase securities, real property, and other investment assets or originate loans. Institutional investors include commercial banks, central banks, credit unions, government-linke ...
to trade blocks of securities directly, rather than through an exchange, providing liquidity and anonymity to buyers.
Third market trading was pioneered in the 1960s by firms such as Jefferies & Company although today there are a number of brokerage firms focused on third market trading, and more recently
dark pool
In finance, a dark pool (also black pool) is a private forum (alternative trading system or ATS) for trading securities, derivatives, and other financial instruments.Boyd L. Jefferies Dies at 70; Headed Institutional Broker New York Times, August 25, 2001