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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.      

Rafael Laguna
Chief Executive Officer

OX’s co-founder and CEO, Rafael Laguna, has been building and growing ... read more >

Frank Hoberg
EVP Sales

Hoberg is a co-founder of Open-Xchange and serves as executive... read more >

Carsten Dirks
Chief Operating Officer

Dirks is responsible for engineering, research & development and daily... read more >

Michael Knapstein
Chief Financial Officer

Knapstein is responsible for Finance, HR, Legal and Corporate Services for... read more >

John Broomfield
VP Marketing

Broomfield is responsible for setting the strategic direction and... read more >

Stephan Martin
EVP Services

Over the past 10 years, Martin has built Open-Xchange’s professional... read more >

Bob Krulcik
SVP, Sales & Business Development - The Americas

Krulcik is responsible for the strategic direction and execution of... read more >

Manny DeJesus
VP Product, Email & Productivity

Manny has over 15 years’ experience in the software and - more specifically... read more >

Bert Hubert
Principal, PowerDNS

With over 20 years in commercial and open source software development and... read more >

Timo Sirainen
Creator & Chief Architect, Dovecot OY

Sirainen programmed the Dovecot IMAP Server in 2002, releasing the first... read more >

OX Supervisory Board

Richard Seibt
Chairman of the Supervisory Board

Richard Seibt has over 35 years’ experience in the IT business and became Open-Xchange Chairman in 2006. As Managing Director at IBM Germany, he handled sales and marketing in Germany, Austria, Switzerland and Eastern Europe. He then worked for IBM North America as VP Software Sales and Marketing and as General Manager worldwide for the OS/2 operating system. 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 Europe, Middle East and Africa. Since leaving Novell in 2005, he has been working as a business angel and board member for several other IT companies.


Dr. Marcus Gulder

Marcus Gulder has been Head of Venture Capital at BayBG Bayerische Beteiligungsgesellschaft since 2012. Gulder played a leading role in building up the VC activities of BayBG from zero to EUR 50 million in 2017. BayBG is focused on investments in Bavarian Tech and SME companies with EUR 320 million capital under management. During Gulder’s 15 years in the VC scene he has led numerous investments, including Medical Intelligence (acquired by Elekta), CAS innovations (acquired by Siemens), SiC Processing (Secondary to Nordic Capital), Activaero (acquired by Vectura Group) and ubitexx (acquired by Blackberry).

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.

Torsten Hauschildt

Torsten Hauschildt is Managing Director of United Internet Investments Holding GmbH where he is in charge for all M&A activities with the UI group as well as the management of the UI investment portfolio. He holds several non-executive board positions in Internet companies, such as home.pl, united-domains, uberall, Cronon and Sedo. Before joining United Internet in 2007, he worked with T-Online as an Investment Manager where he was responsible for France and Spain. Prior to T-Online he was with SAP SI Business Consulting and KPMG as Senior Project Manager.

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.

Bernhard Wöbker

Bernhard Wöbker worked as CEO and president at Nixdorf USA during the company’s expansion in the US before moving on to hold leading positions at Pyramid, NeXT and Versant, a listed US enterprise software company. He also worked as a consultant for Warburg Pincus, one of the largest US private-equity investors. Recently, Wöbker headed Munich-based software provider Brainloop. He now serves as Chairman of the Supervisory Board at the business intelligence provider, Jedox.

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