In 1877, starting from September, New York City residents began to have the opportunity to check the time on clock with the "time ball", located on the roof of constructed in the same year a new corporate headquarters - Western Union Building. In October 2006 the company made an initial public offering of shares on the New York Stock Exchange, becoming independent from First Data company. Sibley, the founder of Western Union, did not build a new telegraph lines, and persuaded the other players to join. American Telegraph Company, however, still had to buy it. Western Union made so that the time in all of American civil services was the same.