3U Holding AG (3U) is a management and investment holding company. The company provides services related to telecommunication and renewable energy sectors. It operates through segments such as telephony, renewable energy segment, and service segment. 3U’s telephony segment comprises of telecommunication companies such as 010017 Telecom GmbH, 3U Mobile GmbH, fon4U Telecom GmbH, Line Call Telecom Ltd, OneTel Telecommunication GmbH, and TriTelA GmbH. The company’s renewable energy segment comprises of 3U Energy AG, 3U SOLAR (PTY) Ltd, ClimaLevel Energy systems GmbH, Wind Park DBF GmbH, SOLAR PARK Adelebsen GmbH, Selfio GmbH, Pelia Building Systems GmbH, Immo GmbH improvement, and EuroSun Vacuum Solar Systems GmbH, among others. 3U is headquartered in Marburg, Germany.