 It was the main competitor to Germany's incumbent carrier, Deutsche Telekom's T-Mobile, also known as D1.Additionally, Mannesmann extended its telecommunications division with integrated services covering mobile and fixed network telephony, Internet, and TeleCommerce with companies in Germany, Italy, UK and Austria 

The Europe-wide telecommunication branch of Mannesmann was extraordinarily successful and so in 1999 the Mannesmann Group hatched a plan to spin off the other divisions.Through a stock exchange flotation under the name of Mannesmann Atecs AG, these industrial divisions were to be combined in a separate enterprise that would be one of the largest companies listed in the German stock index DAX.