OX Leadership Team

Great Companies Start With an Awesome Team

At Open-Xchange, leadership is more a mindset than a title. The nature of our organization is geared towards a flat hierarchy and an open way of working together. The leadership team supports this approach through a mix of business expertise, entrepreneurial experience and operational know-how. Our culture encourages an open approach – exploring, experimenting and mixing things up. You can see the results everywhere – in our people, in our partners and how we develop multi-cultural teams.

OX Supervisory Board

Richard Seibt

Chairman of the Supervisory Board

Since 1978 Richard Seibt profits from a long experience in the IT business and has served as Chairman of the Open-Xchange Supervisory Board, apart from a short break in 2021, since December 2006. As Managing Director at IBM Germany, he handled software sales and marketing in Germany, Austria, Switzerland and Eastern Europe. He then worked as VP Software Sales and Marketing North America and as General Manager for a worldwide operating system software Division. In 1998, he became an Executive Management board member at United Internet. In 2003, Seibt was appointed CEO at SuSE Linux and in 2004 (following the company’s acquisition by Novell), he became President of Novell EMEA (Europe, Middle East and Africa). Since leaving Novell in 2005, he has been working as a business angel and board member for several other international software companies.

Dr. Paul-Josef Patt

Dr. Paul-Josef Patt is CEO of eCAPITAL entrepreneurial Partners, a German venture capital company. He has worked as a Project Manager at Roland Berger & Partner, the leading German strategy consultancy and as Director of Corporate Strategy at Kaufhof Holding, managing the expansion of one of Germany’s biggest retailers. After his successful exit, Patt started working as a business angel and venture capitalist. He took over the lead at eCAPITAL in 2004 and has overseen the company’s impressive growth. He has a strong track record in financing and developing young high-tech companies and as lead investor, initiated the sale of Novaled to Samsung in 2013 – at that time, the largest venture capital deal in the German hi-tech sector. Patt serves on several boards, including sonnen, Jedox AG and Heliatek.

Curt Gunsenheimer 

Curt Gunsenheimer, Senior Partner at Iris Capital, joined the company in 2002. He is responsible for investments in late-stage and growth capital across Europe and supports companies across Germany and France in stages of global expansion. Gunsenheimer has twenty years of experience in venture capital and public-market financing of growth technology companies, with particular expertise in the field of software. Prior to joining Iris Capital, he worked at Goldman Sachs and Robertson Stephens.

Patrick Schaudel

Patrick Schaudel, SVP Product at IONOS With many years of experience in the IT and software industry, Patrick is a proven expert for cloud-solutions, e-business and online marketing with focus on the SMB business. At IONOS, he and his teams are responsible for the entire product portfolio for the digital success of companies of all sizes as well as the public sector. In previous positions at companies like BBDO and Haufe Group, he held several positions in B2B marketing and sales as well as product management with the focus on digital transformation.

John Street 

Director, CEO of Pax8

John Street is an award-winning entrepreneur who has launched a range of companies, including four that garnered Inc. 500 status. He has also served on several commercial Boards and been involved in a wide variety of startups, ranging from telecommunications and high tech to agricultural biotech. He is currently CEO of Pax8, which is creating a complete cloud commerce marketplace, aggregating leading solutions for outsourced IT service providers to efficiently manage their clients’ cloud operations. Street was formerly responsible for the growth of Telephone Express, before founding USA.Net, which launched the world’s first web-based email service. In addition to serving a Chairman of MS Biotec, he also went on to found MX Logic in 2002, which became one of the world’s largest providers of email and web security and is now part of McAfee/Intel. He is currently Chairman Emeritus of the Colorado Springs Philharmonic and serves on the Board for the Institute for Cultural Evolution.

Katja Speck

Katja Speck is CMO at robo advisor and SaaS provider VisualVest where she is responsible for Innovation, Marketing, Product and Sustainability. Prior to that, she held responsible positions in the tech industry for over 15 years, including General Manager of the non-profit organization ID4me, part of the team of SPRIND - Federal Agency for Disruptive Innovation and VP Marketing, Sales and Business Development at international eCommerce specialist asknet. She has been closely networked with the tech scene in Europe, the Americas, and Israel for years and shares her experience as a lecturer at Karlsruhe University of Applied Sciences. She regularly speaks on innovation and impact topics at renowned conferences such as DLD. In 2019, she was awarded the "InspiringFifty DACH" prize, a non-profit organization whose mission is to increase diversity in the technology industry.

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OX Leadership Team


Andreas Gauger

Chief Executive Officer

OX's CEO Andreas Gauger has been heavily involved in shaping the cloud and hosting market in Germany since...

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Frank Hoberg

Chief Sales Officer

Hoberg co-founded Open-Xchange together with Rafael Laguna (now Director SprinD) in 2005 and serves as Chief Sales Officer...

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Dirk Valbert

Chief Financial Officer

Valbert is responsible for Finance, Legal and Corporate Services at Open-Xchange. He is an experienced management...

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Stephan Martin

Chief Operations Officer

Over the past 16 years, Martin has built all Open-Xchange’s services teams from scratch, creating the global services...

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Stefan Preuss

SVP Project Delivery

Preuss leads the project delivery department and engineering for all OX App Suite Cloud platform related products at Open-Xchange.

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Bob Brandt

VP, PowerDNS Engineering, PowerDNS

Brandt manages the PowerDNS Engineering team and is ultimately responsible for Open-Xchange's suite of PowerDNS products.

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Timo Sirainen

Creator & Chief Architect, Dovecot OY

Sirainen programmed the Dovecot IMAP Server in 2002, releasing the first version later that year.

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Matthias Biggeleben

SVP Engineering, App Suite Engineering

Biggeleben leads the engineering and development teams for OX App Suite. Since joining Open-Xchange...

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