Philadelphia Stock Exchange

The Philadelphia Stock Exchange (PHLX) is the oldest stock exchange in the United States. Located in Philadelphia, Pennsylvania, it was founded in 1790. It merged with the Baltimore Stock Exchange in 1949, the Washington Stock Exchange in 1954 and the Pittsburgh Stock Exchange in 1969.In December 1968, in response to a fiscal crisis, the City of Philadelphia imposed a $0.05-per-share stock transfer tax for all transactions on the PHLX. In response, on January 2, 1969, the PHLX moved its trading floor to an office building--then known as the Decker Building--just across City Avenue in Bala Cynwyd to avoid the tax. In February, a court ruled that the tax was illegal, and the PHLX moved its trading floor back to its headquarters in the city.
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A securities exchange where American and European foreign currency options  on spot exchange rates are traded.