Philadelphia Stock Exchange that the tax was illegal, and the PHLX moved its trading floor back to its headquarters in the city. In 1981, the exchange moved to 19th and Market, where it stayed until 2017 when it moved to its current location in the newly built FMC Tower. The exchange merged with the Baltimore Stock Exchange in 1949. The exchange was then named the Philadelphia-Baltimore Stock Exchange. The Baltimore Stock Exchange then migrated out of its Baltimore Stock Exchange Building, later renamed the Totman Building, to a new home base in Philadelphia. The exchange merged with the Washington Stock Exchange in 1954.
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