Our most popular CAOS blog post of the year, by some margin, was this one, from early June, looking at the trend towards persmissive licensing, and the decline in the usage of the GNU GPL family of licenses.
Prompted by this post by Bruce Byfield, I thought it might be interesting to bring that post up to date with a look at the latest figures.
NB: I am relying on the current set of figures published by Black Duck Software for this post, combined with our previous posts on the topic. I am aware that some people are distrustful of Black Duck’s figures given the lack of transparency on the methodology for collecting them. Since I previously went to a lot of effort to analyze data collected and published by FLOSSmole to find that it confirmed the trend suggested by Black Duck’s figures, I am confident that the trends are an accurate reflection of the situation.
The figures indicate that not only has the usage of the GNU GPL family of licenses (GPL2+3, LGPL2+3, AGPL) continued to decline since June, but that the decline has accelerated. The GPL family now accounts for about 57% of all open source software, compared to 61% in June.
As you can see from the chart below, if the current rate of decline continues, we project that the GPL family of licenses will account for only 50% of all open source software by September 2012.
That is still a significant proportion of course, but would be down from 70% in June 2008. Our projection also suggests that permissive licenses (specifically in this case, MIT/Apache/BSD/Ms-PL) will account for close to 30% of all open source software by September 2012, up from 15% in June 2009 (we don’t have a figure for June 2008 unfortunately).
Of course, there is no guarantee that the current rate of decline will continue – as the chart indicates the rate of decline slowed between June 2009 and June 2011, and it may well do so again. Or it could accelerate further.
Interestingly, however, while the more rapid rate of decline prior to June 2009 was clearly driven by the declining use of the GPLv2 in particular, Black Duck’s data suggests that the usage of the GPL family declined at a faster rate between June 2011 and December 2011 (6.7%) than the usage of the GPLv2 specifically (6.2%).
UPDATE – It is has been rightfully noted that this decline relates to the proportion of all open source software, while the number of projects using the GPL family has increased in real terms. Using Black Duck’s figures we can calculate that in fact the number of projects using the GPL family of licenses grew 15% between June 2009 and December 2011, from 105,822 to 121,928. However, in the same time period the total number of open source projects grew 31% in real terms, while the number of projects using permissive licenses grew 117%. – UPDATE
As indicated in June, we believe there are some wider trends that need to be discussed in relation to license usage, particularly with regards to vendor engagement with open source projects and a decline in the number of vendors engaging with strong copyleft licensed software.
The analysis indicated that the previous dominance of strong copyleft licenses was achieved and maintained to a significant degree due to vendor-led open source projects, and that the ongoing shift away from projects controlled by a single vendor toward community projects was in part driving a shift towards more permissive non-copyleft licenses.
We will update this analysis over the next few days with a look at the latest trends regarding the engagement of vendors with open source projects, and venture funding for open source-related vendors, providing some additional context for the trends related to licensing.