Jörg Schönenborn

T-Com provides telecommunications services to the carrier's fixed-line telecommunications network in Germany. It provides international carrier services, terminal equipment and data communications services and offers services to residential customers and small to midsized businesses. It also provides Deutsche Telekom's fixed-line network infrastructure services and offers these services to other telecom carriers. The company is headquartered in Bonn, Germany.

T-Mobile Netherlands Holding BV operates as a holding company with activities in the telecommunication sector. The company is headquartered in The Hague, the Netherlands.

T-Systems International GmbH engages in the development, implementation, operation, and marketing of client- and industry-specific solutions in the information processing and telecommunications sectors. These include security, data processing, information management, training, and consulting services. The company was founded on August 30, 2004 and is headquartered in Frankfurt, Germany.

Founded in 1999, Deutsche Telekom IT GmbH is a German software development company that develops software applications. The company is based in Bonn, Germany and is a subsidiary of Deutsche Telekom AG.

DTM Deutsche Tele Medien GmbH provides telephone directories such as Das Telefonbuch, Das Örtliche, and Gelbe Seiten. The company was founded on November 15, 1954 and is headquartered in Frankfurt, Germany.

Part of Deutsche Telekom AG, GTS Central European Holding BV is a company based in Amsterdam, Netherlands. The Dutch company functions as an investment holding company.

T-Mobile Czech Republic a.s. provides telecommunications services. The company offers mobile telecommunication services, internet, television, mobile phones, tablets, laptops and modems. The company was founded on February 15, 1996 and is headquartered in Prague, Czech Republic.

Part of Deutsche Telekom AG, DeTeFleetServices GmbH is a German company that provides mobility solutions. The company is based in Bonn, Germany. The CEOs of the company are Olga Nevska, Rainer Heil.

Part of Carl-Zeiss-Stiftung, Carl Zeiss, Inc. is a company that manufactures optical lenses. The company is based in Maple Grove, MN.

Robert Bosch GmbH engages in the development of the engineering and electronics sector. Its business sectors include; mobility solutions, industrial technology, consumer goods, and energy and building technology. The company was founded by Robert Bosch in 1886 and is headquartered in Gerlingen-Schillerhöhe, Germany.

Slovak Telekom, a.s. provides telecommunication services to residential and corporate clients in Slovakia. It offers a range of services, including voice and data services through landline and mobile telecommunication networks, Internet connectivity, digital TV services, MMS messaging services, and roaming services. Slovak Telekom was founded on April 1, 1999 and is headquartered in Bratislava, Slovakia.

Part of Deutsche Telekom AG, DeTeAssekuranz Holding GmbH provides management services. The company is based in Cologne, Germany. The CEOs are Andreas Mauerer, Roland Ring, Jürgen Hennig. The German company was founded in 2017.