T-Mobile is the brand name used by some of the mobile communications subsidiaries of the German telecommunications company Deutsche Telekom AG in the Czech Republic, Poland and the United States.
Siemens AG is a German multinational technology conglomerate. It is focused on industrial automation, distributed energy resources, rail transport and health technology. Siemens is the largest industrial manufacturing company in Europe, and holds the position of global market leader in industrial automation and industrial software.
Deutsche Telekom AG is a German telecommunications company headquartered in Bonn and is the largest telecommunications provider in Europe by revenue. It was formed in 1995 when Deutsche Bundespost, a state monopoly at the time, was privatized. Since then, Deutsche Telekom has consistently featured among FortuneMagazine's top Global 500 companies by revenue, with its ranking as of 2023 at number 79. In 2023, the company was ranked 41st in the Forbes Global 2000. The company operates several subsidiaries worldwide, including the mobile communications brand T-Mobile. It is the world's fifth-largest telecommunications company by revenue.
Swisscom AG is a major telecommunications provider in Switzerland. Its headquarters are located in Worblaufen near Bern. The Swiss government owns 51% of Swisscom. According to its own published data, Swisscom holds a market share of 56% for mobile, 50% for broadband and 37% for TV telecommunication in Switzerland. Its Italian subsidiary, FASTWEB, is attributed 16% of private clients and 29% of the corporate clients share of Italian broadband and is also active in the mobile market.
Koninklijke KPN N.V., trading as KPN is a Dutch telecommunications company. KPN originated from a government-run postal, telegraph and telephone service and is based in Rotterdam, Netherlands.
Aastra Technologies Limited, formerly headquartered in Concord, Ontario, Canada, made products and systems for accessing communication networks, including the Internet. Its products included residential and business telephone terminals, screen telephones, Enterprise private branch exchanges (PBX), network access terminals and high-quality digital video encoders, decoders and gateways. Residential telephone equipment was sold in the United States as Bell equipment by Sonecor brand, which represented Southern New England Telecommunications.
Hrvatski Telekom, also known as HT or Telekom, is a Croatian telecommunications company founded in 1998. Headquartered in Zagreb, it is majority-owned by Deutsche Telekom with a 53.5% stake and is publicly traded on the Zagreb Stock Exchange.
Tessellis S.p.A. is an Italian telecommunications company founded in 1998 and based in Cagliari, Sardinia, that provides Internet and telecommunications services in Italy, and, previously had operations in other European nations through its acquisition of many smaller European Internet Service Providers (ISPs) in the late 1990s.
Debitel AG was one of the largest mobile telephone services providers in Europe, offering a wide range of telecommunication products – mobile and land-line telephony as well internet services. At its peak, the business commanded a 47% market share of the mobile service provider market in Germany with 12.4% of the overall mobile telephone market as of 2004. The company boasted over 10.2 million customers of which 8.3 million were resident in Germany.
Oi, formerly known as Telemar, is the largest fixed telephone operator and the fourth mobile telephone operator in Brazil, being the third largest telecommunication company in Latin America. It is headquartered in Rio de Janeiro.
Centennial Communications and its subsidiaries provided wireless and broadband telecommunications services to wireless telephone subscribers in the United States, Puerto Rico, and the U.S. Virgin Islands. On March 13, 2007, Centennial Communications completed the sale of Centennial Dominicana to Trilogy International Partners for approximately $80 million in cash.
Arcor is the former name of the fixed phone line and Internet business of Vodafone D2 GmbH, a German subsidiary of telecommunications company Vodafone. It is the second-largest provider of fixed phone lines in Germany after Deutsche Telekom. Its name changed on 1 August 2009 after Vodafone completed acquisition of the company. Its headquarters were in Eschborn near Frankfurt. It is one of the few telecommunications companies in Germany to operate an ISDN network that is independent of the incumbent provider Deutsche Telekom.
Mannesmann was a German industrial conglomerate. It was originally established as a manufacturer of steel pipes in 1890 under the name "Deutsch-Österreichische Mannesmannröhren-Werke AG". In the twentieth century, Mannesmann's product range grew and the company expanded into numerous sectors; starting from various steel products and trading to mechanical and electrical engineering, automotive and telecommunications. From 1955, the conglomerate's management holding with headquarters in Düsseldorf was named Mannesmann AG.
Simyo is a brand for various mobile virtual network operators (MVNOs) in Europe. In the Netherlands, it is owned by KPN. In Spain, it is owned by Orange España. In Germany, it was relaunched in August 2024 by mobilezone GmbH and Telefonica Germany.
Porsche Automobil Holding SE, usually shortened to Porsche SE, is a German multinational corporation primarily known as a holding company of Volkswagen Group with investments in the automotive industry. Porsche SE is headquartered in Zuffenhausen, a city district of Stuttgart, Baden-Württemberg and is majority owned by the Austrian-German Porsche-Piëch family. The company was founded in Stuttgart as Dr. Ing. h.c. F. Porsche GmbH in 1931 by Ferdinand Porsche (1875–1951) and his son-in-law Anton Piëch (1894–1952).
United Internet AG is a global Internet services company headquartered in Montabaur, Rhineland-Palatinate, Germany. The company is structured in two business areas, Access and Applications, and has a total of 16 brands and numerous subsidiaries. The well-known brands under the umbrella of United Internet AG include 1&1, IONOS, Fasthosts, GMX, WEB.DE and 1&1 Versatel.
Viya is a telecommunications company that provides landline, mobile telephone, Internet, and cable television services in the United States Virgin Islands. Viya is a subsidiary of ATN International. Prior to its acquisition by ATN, it was formerly known as Innovative Communications Corporation. In 2015, Choice Communications, which was a former rival telecommunications company and a subsidiary of ATN, purchased Innovative for $145 Million and completed the sale on July 1, 2016. In 2017, ATN merged both Innovative and Choice to form Viya.
Sedo is a domain name and website marketplace and domain parking provider based in Cambridge, Massachusetts and Cologne, Germany. The company is a subsidiary of United Internet.
1&1 AG is a German telecommunications service and landline and mobile telecommunications provider headquartered in Montabaur, Rhineland-Palatinate and listed on the TecDAX. Since 2017, the majority of the company has belonged to United Internet.
Sunrise LLC, doing business as Sunrise, is a Swiss telecommunications provider based in Zurich, owned by Liberty Global. It provides mobile, TV and landline phone and internet services. Since February 2019, Sunrise headquarters are located at Thurgauerstrasse 101b, Glattpark Opfikon. Formerly a subsidiary of TDC A/S, Sunrise had been owned by CVC Capital Partners until 2015. In February 2015, CVC realised an IPO on the SIX Swiss Exchange. Since then, Sunrise stocks are publicly traded at the Swiss Stock Exchange. In August 2020, Liberty Global announced that it will be acquiring Sunrise for $7.4 billion. The transaction was completed on November 11, 2020.
