The Scope of Open Source Licensing

This article is an initial exploration of the determinants of open source license choice. It first highlights how the decision is shaped not just by the preferences of the licensor itself, but also by that of the community of developers. The article then presents an empirical analysis of the determinants of license choice using the SourceForge database, a compilation of nearly 40,000 open source projects. Projects geared toward end-users tend to have restrictive licenses, while those oriented toward developers are less likely to do so. Projects that are designed to run on commercial operating systems and whose primary language is English are less likely to have restrictive licenses. Projects that are likely to be attractive to consumers--such as games--and software developed in a corporate setting are more likely to have restrictive licenses. Projects with unrestricted licenses attract more contributors. These findings are broadly consistent with theoretical predictions. Copyright 2005, Oxford University Press.