We are the Guardians of Europe´s Digital Freedom
Cybersecurity for Freedom to Operate in the Digital World
We tackle the challenge of a world being reshaped by geopolitical shifts, disruptive technologies, and cyber threats. As digital infrastructure is the critical backbone, organizations must secure what they rely on today and prepare for what they will depend on tomorrow. For us and our clients, freedom to operate is crucial.
That requires sovereignty and resilience. Sovereignty enables organizations to be in control of their core assets. Resilience ensures continuity when disruption hits. Together, they create the foundation for long-term capability.
secunet empowers organizations to build that foundation from daily operations to critical missions.
As a trusted high-security partner, we combine superior technology with comprehensive services from one source.
Together with clients, trusted partners, and authorities we create compliant-by-design cybersecurity solutions that perform where it matters most.
They secure digital ecosystems, from edge to cloud, from smartphones to satellites.This is how we make the digital world a safe place to act and grow. For our global customers, it means freedom to operate.
For Europe, it is our commitment to safeguard digital freedom.
Our Company Values:
genuine · cooperative · inquiring · open‑minded · proficient
Our 1,300+ “secunauts” are wholly committed to their work, open to change and always ready to take on new challenges. We all play our part in the success of secunet, and we are all committed to these communally defined values: they form the basis of our highly productive teamwork and show who we are.
We are honest in our dealings with each other and with our clients, and we take responsibility together. We can always rely on each other.
We work with and on behalf of other people, driven by a shared mission. We help and encourage each other – for our own benefit and for that of our clients and society in general.
From board level to trainee, we talk openly about mistakes and ask questions. Because that’s how we learn from each other and further our development.
We maintain strong relationships with our clients and achieve high-quality results on their behalf. We are able to achieve this by virtue of our experience, collaborative strengths and empathy for the needs of others.
Our desire for knowledge is one of our most important resources. We create the space in which to foster it. We try out new things and follow them through with passion to their logical conclusion.
How we live our values
secunet in a nutshell
secunet Security Networks AG operates through the divisions Critical Infrastructures, Homeland Security, Public Authorities and Defence & Space. The company's clients include federal ministries, most DAX-listed corporations, and international government agencies and organizations. The company is IT security partner of the Federal Republic of Germany and a partner of the Alliance for Cyber Security.
secunet was founded in 1997, is listed on the SDAX, and generated revenue of approximately 459 million euros in 2025. The main shareholder is Giesecke & Devrient GmbH, Munich.
Our locations in Germany
secunet
secunet Security Networks AG
Kurfürstenstraße 58
45138 Essen
secunet
secunet Security Networks AG
Alt Moabit 96
10559 Berlin
SysEleven
SysEleven GmbH
Boxhagener Str. 80
10245 Berlin
secunet
secunet Security Networks AG
Dreizehnmorgenweg 6
53175 Bonn
secunet
secunet Security Networks AG
Ammonstraße 74
01067 Dresden
secunet
secunet Security Networks AG
Mergenthalerallee 77
65760 Eschborn
secunet
secunet Security Networks AG
Osterbekstraße 90 b
22083 Hamburg
secunet
secunet Security Networks AG
Werner-von-Siemens-Straße 6
98693 Ilmenau
The Management Board of secunet AG
Marc-Julian Siewert has joined secunet Security Networks AG in July 2025 in the capacity of Chief Executive Officer (CEO) and Chairman of the Management Board. He brings with him many years of international experience in various areas of the high-security industry.
Marc-Julian Siewert completed his studies of business and management in the UK, Canada, USA and Spain. Following his Master’s degree, he worked in technology consulting for two years, before joining Papierfabrik Louisenthal GmbH in 2013 as Vice President Key Accounts. From 2015, he held various roles in Sales & Marketing in the Currency Technology division of Giesecke + Devrient GmbH, where he spent many years abroad.
He was appointed Group Vice President and Head of Value Added Solutions and Services at the same company in fall 2018. Before joining secunet, he was a member of the management board of Veridos GmbH for six years, including more than three years as CEO.
Torsten Henn started at secunet GmbH back in 1997 as a consultant and project manager and took on various management positions within the company. In the course of secunet's realignment, Torsten Henn joined the extended Management Board as Chief Operating Officer (COO) in 2015 and has been a member of the Management Board since June 2019.
Torsten Henn studied Computer Engineering in Siegen and worked for Telekom before joining secunet. He then worked for RWTÜV Anlagentechnik and TÜV Informationstechnik. Since 1994, Torsten Henn has been working exclusively on the subject of IT security.
Dr Kai Martius has been Chief Technology Officer since 2015 and a member of the Management Board of secunet Security Networks AG since 2019.
He is one of the key architects of the SINA IT high-security solution and also has extensive experience in the design, implementation and use of IT security products in the public sector.
He joined secunet back in 1999 and was responsible for various topics in consulting and product development. Between 2007 and 2015, he was the Head of the High Security / Public Sector division at secunet.
Dr Martius holds a doctorate in electrical engineering from the Technical University of Dresden.
Jessica Nospers was appointed to the Management Board of secunet Security Networks AG as Chief Financial Officer (CFO) in June 2024.
Jessica Nospers studied business administration at Saarland University, Germany. She began her professional career in 2004 at Deloitte in the Transaction Advisory Services division. During her almost 10 years there, she gained extensive knowledge and experience in the areas of M&A and auditing. In this time, she successfully passed the auditor exam and level I to III of the CFA charterholder exam. Before joining secunet, she was Group Director Finance at Hengst SE and Group CFO at fernao group GmbH.
The Supervisory Board of secunet AG
The Supervisory Board of secunet Security Networks AG is comprised of six members. Four members are elected by the shareholders and two members by the employees in accordance with the One-Third Participation Act pertaining to employees on the Supervisory Board (Drittelbeteiligungsgesetz).
Supplier Code of Conduct
For more information about our Compliance Management System and our Code of Conduct for Suppliers, please click here:
Learn more about governance at secunet
Quality and Environmental Management
Living quality, acting sustainably
Our thinking and approach has always been driven by quality. Not just in our products, but in all our processes and services. That is why we have voluntarily committed ourselves to shaping quality formally, actively, comprehensively and continuously. We have the results of these efforts regularly audited by independent auditors. Our quality management system is certified in accordance with DIN EN ISO 9001.
These points are particularly important to us:
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