Martin Grashoff

Rentrop Investment Office (RIO), locally known as Rentropsche Vermögensverwaltung, is an independent German multi-family office which was founded by Norman Rentrop in 1975. The firm operates as part of the family office which manages the wealth of the Rentrop family. The family traces their history to 1510 in Southern Westfalia and is spread across Germany and the US. Headquartered in Bonn, RIO also manages separate portfolios.

Part of International Masters Publishers Holding AB, NE GmbH provides educational resources and tools for students to develop media literacy skills. The company is based in Munich, Germany. The CEOs are Alf Lennart Tönnesson, Martin Tönnesson. The German company was founded in 1998.

Part of freenet AG, Freenet Digital, LLC is a company that provides mobile video service and entertainment platforms. The company is based in Sherman Oaks, CA. The CEO of the company is Christoph Vilanek. Freenet Digital was acquired by freenet Cityline GmbH from Jesta Group Corp. on January 15, 2014.

Media Broadcast GmbH provides television, media and entertainment services. Its services include television solutions, network services, radio and event broadcasting, satellite systems, and internet services. The company was founded in 1961 and is headquartered in Cologne, NW.

gamigo AG engages in the development, publishing, and distribution of online and mobile games. The firm’s portfolio of gaming titles includes ArcheAge, Trove, Aura Kingdom, Desert Operations, Fiesta Online, Defiance 2050, Ironsight, RIFT, Echo of Soul, Grand Fantasia, Eden Eternal, Wargame 1942, Kings and Legends, Shaiya, and Twin Saga. The company was founded in 2000 and is headquartered in Hamburg, Germany.

Ströer Management SE is a private company based in Cologne, Germany. The CEOs of the German company are Udo Müller, Christian Schmalzl. The company provides management services.

Part of Ganske Verlagsgruppe GmbH, Gräfe und Unzer Verlag GmbH is a leading German-language guidebook brand based in Munich, Germany. The CEOs of the German company are Thomas Ganske, Ulrich Ehrlenspiel, David Gottscheber. The company is known for its quality and innovative guidebooks, which are available in various retail outlets. In addition to guidebooks, the company also offers creative and cross-media content solutions for brands and companies.

Verlag Norman Rentrop operates as an investment company. The company was founded by Norman Rentrop in 1975 and is headquartered in Bonn, Germany.

Ravensburger Interactive Media GmbH is based in Ravensburg, Germany. Part of Embracer Group AB, Ravensburger Interactive Media GmbH is a German company that produces the game "kakerlakak" where players try to catch the most cockroaches by cleverly manipulating cutlery. Ravensburger Interactive Media was acquired by JoWooD Entertainment AG from Ravensberger Bau-Beteiligungen AG on May 16, 2002.

GVG Solutions GmbH develops applications for electronic travel guides and travel advice. The private company is based in Hamburg, Germany. The CEOs of the German company are Sebastian Ganske, Carsten Tegeler.

debitel AG provides mobile & fixed-line telecommunications services, internet and data services. It is a network-independent telecommunications company that offers mobile telephony, fixed-line telephony and the internet. It does all of this by purchasing capacity from various network operators, which it then supplements and combines to create its own products and packages. It works in Germany with the mobile telephony operators like T-Mobile, Vodafone and E-Plus. The company was founded in 1991 and is headquartered in Stuttgart, Germany.

Exaring AG provides IP entertainment services. The company is headquartered in Munchen, Germany.

Netzpiloten AG designs online applications to help the users to navigate through the web. It operates through the following segments: social media, mobile network, lifestyle, interviews, link advices, and technology. The company was founded by Wolfgang Stephan Macht in 1998 and is headquartered in Hamburg, Germany.

mobilcom-debitel GmbH provides telecommunications services. The company is headquartered in Budelsdorf, Germany.

Part of PEH Wertpapier AG, GRAVIS Computervertriebsgesellschaft mbH is a leading Apple retailer in Germany, offering a wide range of Apple products including Mac, MacBook, iPad, Watch, TV, and iPhone. GRAVIS Computervertriebsgesellschaft mbH is based in Berlin, Germany. The German company provides technical support, service offers, and attractive specials both online and in 40 physical stores across the country. The company was founded by Archibald Horlitz, and the CEOs are Jochen Otterbach and Jan Sperlich. In 2013, the company was acquired by mobilcom-debitel GmbH.