Investopedia explains 'Instinet'
Instinet was founded in 1967 as Institutional Networks. It is Wall Street's oldest electronic communications network (ECN), and after it was acquired by Reuters Group in 1987, it and other ECNs evolved into major threats to the established stock exchanges. The company split its ECN and its brokerage business into Inet ECN and Instinet, respectively, in 2003. NASDAQ then acquired Inet ECN in 2005 and Instinet was sold to a private equity firm. In addition to sales trading, Instinet provides front-end technology, algorithmic trading, liquidity sourcing, independent research, commission management and transaction analysis.