The Pittsburgh Stock Exchange was a large regional stock market located in Pittsburgh, Pennsylvania from November 11, 1864 (originally as Thurston's Oil Exchange) until closing on August 23, 1974. It was alternatively named the Pittsburgh Coal Exchange starting on May 27, 1870, and the Pittsburgh Oil Exchange on July 21, 1878 with 180 members. On July 25, 1896 the Exchange formally took the name Pittsburgh Stock Exchange though it had been referred to by that name since the spring of 1894. The Exchange, like many modern day exchanges, was forced to close during sharp economic crashes or crises. On December 24, 1969 The Philadelphia-Baltimore-Washington Stock Exchange bought the Pittsburgh Stock Exchange. At its height the exchange traded over 1,200 companies, but by the last trading day in