Open Source License Popularity
John T. Haller, August 28, 2009
Popularity of individual open source license usage is tracked by several entities with the results published online. I thought it would be interesting to combine the license types that are similar and map out the overall popularity along with OSI and FSF approval and GPL compatibility. As you can see, the GPL/LGPL is the most popular license by a wide margin. The next 3 licenses are all GPL compatible in some way meaning up to 80% or more open source code is GPL compatible (you can't tell exactly as some version issues enter into the mix with the Apache and Perl licenses).
| License | Percent | OSI Approved | FSF Approved | GPL Compatible |
|---|---|---|---|---|
| GPL/LGPL (2 & 3) | 64.83% | Yes | Yes | Yes |
| New BSD / MIT | 10.21% | Yes | Yes | Yes |
| Artistic License (Perl) | 8.72% | Yes | Yes (2 Only) | Yes (AL v2 Only) |
| Apache License | 3.97% | Yes | Yes | Yes (GPL3 Only) |
| Code Project Open License | 3.28% | No | No | No |
| Mozilla Public License | 1.52% | Yes | Partially* | No (Unless Specified) |
| Microsoft Public License | 1.16% | Yes | Partially* | No |
| Common Public License | 0.58% | Yes | Yes | No |
| zlib/libpng License | 0.45% | Yes | Yes | Yes |
| Eclipse Public License | 0.45% | Yes | Yes | No |
Statistics from Black Duck Software from August 28, 2009.
* the FSF recognizes the license as a free software license but recommends against using it
