In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. In April 1851 companions registered in Albany New York and Mississippi Valley Printing Telegraph Company (NYMVPTC), which included founded two years before New York State Printing Telegraph Company. In October 2006 the company made an initial public offering of shares on the New York Stock Exchange, becoming independent from First Data company. In 1849, Selden and Sibley, the founders of the future Western Union, created the New York State Printing Telegraph Company. Western Union made so that the time in all of American civil services was the same.