Publication Title

Washington University Journal of Law & Policy


free and open source software, Simple Public License

Document Type



A decade ago, I observed that licenses were the "unnoticed force" behind free and open source software ("FOSS"). Since then, legal scholarship on FOSS licensing has gone from a trickle to a torrent. Likewise, economists, political scientists, and anthropologists (among others) have begun to focus on FOSS licensing, each from their own academic perspectives. FOSS programmers themselves (known as "hackers" in the FOSS community) have refocused on FOSS licensing, most notably by revising the most venerable FOSS license, the GNU General Public License ("GPL"), for the first time in more than fifteen years.

One prominent issue among hackers and business users (but less noticed by legal scholars) has been "license proliferation." "Proliferation" refers to the scores of open source licenses that are now in use, with more being created all the time. The Open Source Initiative ("OSI") has certified more than sixty licenses as conforming to the Open Source Definition, a key measure of whether a license embodies FOSS principles. Hackers believe that license proliferation encumbers and retards the success of FOSS. The OSI has identified the issue as one of its most strategic matters to address.

This Article analyzes the license proliferation issue. In general, it examines whether the growing number of FOSS licenses represents hopeless confusion (as many hackers assume) or, instead, helpful diversity. In particular, it discusses why proliferation occurs and the pros and cons of multiple licenses. It points out that the primary culprits of license proliferation are often the loudest critics: those hackers who remain wed to legacy license forms, unwilling to replace outdated, poorly drafted, or legally insufficient licenses with newer versions. This means the FOSS community can only improve licenses by adding new ones.

The Article concludes with an analysis of the role that OSI has played and can play to ameliorate the negative effects of so many FOSS licenses. To give the discussion context and color, the Article draws on my experience in submitting the Simple Public License to the OSI for certification.

Included in

Computer Law Commons



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