Management

Chief Executive Officer (CEO) Chairman of the Management Board of Telefónica Deutschland Holding AG Member of the Group Executive Committee of Telefónica S.A. Santiago Argelich Hesse has been Chief Executive Officer (CEO) of Telefónica Deutschland Holding AG and a member of the Group Executive Committee of the international Telefónica Group since January 2026. As CEO, he is responsible for the strategic direction of O₂ Telefónica in a dynamic market and in Europe's largest economy. He leads one of the largest and fastest-growing full-service provider of telecommunications solutions for residential and business customers in Germany in recent years. An excellent network, more than 35 million mobile connections, 2.4 million landline customers, and a comprehensive range of innovative digital services in the areas of the Internet of Things, security, entertainment, and data analysis make O₂ Telefónica a key player in the country's digitalization. Santiago Argelich Hesse has more than 20 years of international experience in the telecommunications and digital industry. He has spent the past seven years working for the telecommunications company Cellnex, the last four and a half of which as CEO of the national subsidiary in Poland. During his time at Cellnex, he played a key role in the expansion of Cellnex Telecom in Europe to more than a dozen countries, including Spain, France, Italy, Switzerland, the UK, and Poland. Prior to this, Argelich held key leadership positions at telecommunications provider Veon and strategy consultancy Oliver Wyman, where he was a senior partner specializing in strategy development and transformation for major telecommunications operators. Santiago Argelich Hesse studied engineering at the Polytechnic University of Catalonia in Spain and holds a postgraduate degree in international marketing strategy from the London School of Economics and Political Science. The German-Spanish national was born in Mülheim an der Ruhr in 1968.

Chief Financial Officer (CFO) Member of the Management Board of Telefónica Deutschland Holding AG Markus Rolle was appointed Chief Financial Officer (CFO) of Telefónica Deutschland Holding AG in August 2017. Following the successful integration of E-Plus, he has focused increasingly on the digitalisation and transformation of the Finance division. He previously worked as Director Controlling at Telefónica Germany from 2014 to 2017. He started his career in the company 20 years ago at E-Plus. As part of his training, he worked in all major corporate divisions and then became Business Analyst in Strategic Long-Term Planning in Controlling. From 2004 onwards, the business graduate held various management positions in the finance department of the E-Plus Group and the KPN Group, including Director Controlling at E-Plus and CFO Consumer Mobile in the Netherlands. From November 2013, he played a key role in preparing the Post Merger Integration (PMI) process between Telefónica Deutschland and E-Plus. In addition, Markus Rolle assumed various management positions at subsidiaries where he was in charge of financial matters. Markus Rolle graduated in business administration from the University of Economics and Management in Essen. He also completed various high potential and executive programmes. He was born in Gelsenkirchen in 1978.

Chief Officer Legal & Corporate Affairs Member of the Management Board of Telefónica Deutschland Holding AG Valentina Daiber has been Chief Officer Legal and Corporate Affairs of Telefónica Deutschland Holding AG since August 2017. In this position she is responsible for the units Legal, Compliance, Corporate Security and Data Protection, as well as the regulatory work of the company and the government offices and the department of Corporate Responsibility & Sustainability (ESG). In addition, Valentina Daiber leads the representative office of Telefónica in the capital Berlin. Prior to this position, the lawyer was Director Corporate Affairs at Telefónica Germany and responsible for the legal departments Regulatory Law, Cartel Law, Telecommunications Law and Media Law as well as for the work with political committees and organisations. Valentina Daiber joined Telefónica Deutschland – then Viag Interkom – in 1999, where she started as advisor in the field of Regulation. Since 2004 she has been working in various leading positions in the company. Prior to her career at Telefónica, Valentina Daiber worked at the Institute for European Media Law in Saarbrücken as well as for the national office for private broadcasters, in Ludwigshafen. Valentina Daiber completed her first legal state examination at the University of Saarbrücken and her second legal state examination at the Oberlandesgericht (higher regional court) Zweibrücken / Palatinate. She was born in Neunkirchen/Saar in 1967.

Chief Organizational Development & People Officer Member of the Management Board of Telefónica Deutschland Holding AG Nicole Gerhardt has been Chief Organizational Development & People Officer of Telefónica Deutschland Holding AG since August 2017. Within this role, she is responsible for the company's human resources. The sustainable orientation towards the digital future and the necessary transformation of the company are the focus of her range of tasks. Shaping this transformation responsibly, in balance with employees and company interests, is a major concern for her. Before joining Telefónica, Nicole Gerhardt was Executive Vice President Human Resources at Pro7/Sat1. From 2013 to 2015, the fully qualified lawyer first worked for the E-Plus Group as Head of HR and, following the merger of Telefónica Deutschland and E-Plus, as Director Business Partnering, Talent, Leadership & Capability Development. Prior to that, Nicole Gerhardt held various leadership positions in Human Resources at Vodafone, both in Germany and internationally, and as Head of HR and Legal, helped build the startup Vizzavi, a joint venture between Vodafone and Vivendi Universal. Nicole Gerhardt began her career as Legal Counsel at Versatel Deutschland GmbH, before leading the HR department there. Nicole Gerhardt studied law at the Ruhr University in Bochum. She was born in Hagen in 1970.

Chief Consumer Officer (CCO) Member of the Management Board of Telefónica Deutschland Holding AG Andreas Laukenmann has been appointed Chief Consumer Officer (CCO) of Telefónica Deutschland Holding AG in September 2023. In addition to the consumer business, he is also responsible for the core brand O₂. Prior to that, he worked for 18 years at the telecommunications company Vodafone. Since 2019, he has been responsible for the consumer business as Managing Director and has held various management positions, including in the Czech Republic and at the former fixed-line subsidiary Arcor. Prior to that, he worked for the consulting firms Diamond Cluster, Booz Allen & Hamilton and Ernst & Young. Andreas Laukenmann studied computer science at the Technical University in Karlsruhe and graduated with a degree in computer science. He was born in Bad Cannstatt in 1970.

Chief Partner & Wholesale Officer Member of the Management Board of Telefónica Deutschland Holding AG Alfons Lösing is Chief Partner & Wholesale Officer at Telefónica Deutschland Holding AG and in this role he is responsible for partnerships and innovative business models. Together with partners, Telefónica Deutschland designs innovative products and services by developing new, integrated business models. This approach addresses both consumers (SuperSelect, LEBARA, LycaMobile, i.a.) and business customers (e.g. Siemens SDI, Transatel, whereverSIM) as target groups. Alfons Lösing is also responsible for digital processes & services and carrier services for the entire brand and partner portfolio of the Telefónica Deutschland Group. Previously, Alfons Lösing was Managing Director of the E-Plus Group and, as Chief Wholesale Officer, responsible for partner models, cooperations, tariffs, products and carrier services. He joined E-Plus in 1993, the year it was founded, and after holding various management positions in finance, he developed and established the Wholesale & Partnering division with the E-Plus multi brand strategy (Schwarzfunk, Simyo, SIMone, Blau.de, Ay Yildiz, Ortel, ALDI Talk, NettoKOM, WhatsAppSIM, i.a.) in 2002. At the beginning of his career, Alfons Lösing worked in various functions for Siemens AG in the plant engineering division. He holds degrees in electrical engineering and Master of Business Administration.

Chief Technology & Enterprise Officer Member of the Management Board of Telefónica Deutschland Holding AG Mallik Rao has been a Member of the Management Board of Telefónica Deutschland Holding AG since end of October 2019. He was initially responsible for the mobile and fixed network as well as the IT of Telefónica Deutschland in his role as Chief Technology & Information Officer. With decision of the Supervisory Board, Mallik Rao has also been assigned responsibility for the business customer division (B2B) as well as the company’s data platforms and artificial intelligence activities in his role as Chief Technology & Enterprise Officer from 5th November 2024. Mallik Rao has more than 25 years of experience in the international telecommunications industry. He lived and worked in seven countries, bringing experience from both technology providers like Ericsson and Nortel as well as from service providers like Vodafone and Aircel. Mallik Rao is passionate about working with various cultures and building technology solutions for customers. Mallik Rao holds bachelor’s degree in communications engineering from Babasaheb Bhimrao Ambedkar University, Aurangabad in India.