In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. Leaving the idea of expansion into Europe, Western Union took up the expansion of services in the U.S. market. In 1879 Western Union left the telephone business after losing a lawsuit against Alexander Graham Bell - the patent holder on the phone. In 1884 Western Union has become a joint-stock company and was brought to the stock exchange. The company has entered in the first American stock index Dow Jones. 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.