Using the example of corporate OSS engagement, Oliver Alexy shows how free revealing can be carried out both effectively and efficiently by companies. He evaluates potential advantages and disadvantages and looks at related organizational processes to understand how this practice diffuses within the corporation and how firms can use it successfully.Over the last decade, the commercial world has more and more embraced open source software such as the Linux operating system. What started out as an ideological movement for Free Software and as a hobbyists thing has largely turned into a ma- stream part of the IT industry. By 2008, even the long-time open source critic Microsoft has created two open source licenses, and it comes as little surprise when Google - leases the complete mobile operating system stack of its Android phone as open source. Yet, how exactly open source software and in particular the open source style of software development are integrated into commercial enterprises is far from being - derstood. Research into open source software and open innovation more broadly only just starts to address these issues. But these questions are of obvious importance for firms considering to launch or extend their open source engagement, and of academic interest to scholars studying open innovation processes.Commercial Open Source Software, Open Source Software: Source of Innovation? Top-Down Adoption of OSS, Bottom-Up Adoption of OSS, Managing OSS-Related Processes, Motivation and Incentivizing of OSS Developers, Summary and Outlook: OSS in the 21st CenturyDr. Oliver Alexy war Wissenschaftlicher Mitarbeiter bei Prof. Dr. Joachim Henkel am Dr. Theo Sch?ller-Stiftungslehrstuhl f?r Technologie- und Innovationsmanagement der Technischen Universit?t M?nchen und ist jetzt am Imperial College London t?tig.The concept of free revealing describes the continually growing practice of companies that release results of their innovation processes to the public rather than plƒ%