As of May 2018, has terminated business in Iran that was previously conducted via a subsidiary, Detecon. ("German rail operator, Deutsche Telekom end Iran projects," Reuters, August 16, 2018.)
According to its 2017 SEC 10-K filing: DT, through certain of its non-U.S. subsidiaries, is party to roaming and interconnect agreements with the following mobile and fixed line telecommunication providers in Iran, some of which are or may be government-controlled entities: Gostaresh Ertebatat Taliya, Irancell Telecommunications Services Company (“MTN Irancell”), Telecommunication Kish Company, Mobile Telecommunication Company of Iran, and Telecommunication Infrastructure Company of Iran. For the year ended December 31, 2017, gross revenues of all DT affiliates generated by roaming and interconnection traffic with Iran were less than $4 million and estimated net profits were less than $4 million.
In addition, DT, through certain of its non-U.S. subsidiaries, operating a fixed line network in their respective European home countries (in particular Germany), provides telecommunications services in the ordinary course of business to the Embassy of Iran in those European countries. Gross revenues and net profits recorded from these activities for the year ended December 31, 2017 were less than $0.4 million. We understand that DT intends to continue these activities.
In a correspondance with the SEC in 2009, Deutsche Telekom disclosed few details regarding their investments in Iran.
"We have bilateral agreements with operators in Iran that provide for termination of traffic into the country and traffic originating from the country. We have roaming agreements with network operators in Iran. Roaming agreements allow our mobile customers to make and receive voice calls, send and receive data, or access other services when traveling outside the geographical coverage area of the home network, by means of using another operator’s network." (CORRESP for DEUTSCHE TELEKOM AG, 11/27/2009)