Philadelphia Stock Exchange Philadelphia Stock Exchange Philadelphia Stock Exchange (PHLX), now known as NASDAQ OMX PHLX, is the oldest stock exchange in the United States. It is now owned by The NASDAQ OMX Group. Founded in 1790, the exchange was originally named the Board of Brokers of Philadelphia, also referred to as the Philadelphia Board of Brokers. In 1875, the Board of Brokers changed its name to the Philadelphia Stock Exchange. The exchange merged with the Baltimore Stock Exchange in 1949 and was named the Philadelphia-Baltimore Stock Exchange. It merged with the Washington Stock Exchange in 1954, becoming known as the Philadelphia-Baltimore-Washington Stock
Chicago Stock Exchange the New Orleans Stock Exchange became part of the Midwest Stock Exchange, and in the early 1960s the Midwest Stock Exchange Service Corporation was established to provide centralized accounting for member firms. In April 1978, the Chicago Stock Exchange launched an Intermarket Trading System (ITS), a system that allowed orders to be sent from one exchange to another to ensure that customers received the best execution available. In the 1980s, the Chicago Stock Exchange made several technological advancements to improve trading. In 1982, the CHX launched the MAX system, which allowed CHX to be one of the first stock exchanges