Jono Bacon on the state of open source licensing;
A little while ago I saw an interesting tweet from Stephen O’Grady at RedMonk on the state of open source licensing, including a graph.
The graph shows how license usage has changed from 2010 to 2017. In reading it, it is clear that usage of the GPL 2.0 license, one of the purest copyleft licenses around, has more than halved in usage. According to the chart it would appear that the popularity of open source licensing has subsequently shifted to the MIT and Apache licenses. There has also been a small increase in GPL 3.0 usage.
So, what does all this mean?
Why has GPL 2.0 usage dropped so dramatically with only a marginal increase in GPL 3.0 usage? Why has MIT and Apache usage grown so dramatically?
Of course, there are many interpretations, but my guess is that this is due to the increased growth in open source in business, and a nervousness around the GPL in the commercial world. Let’s dig in.
The GPL and business
Now, before I get started, I know I am going to raise the ire of some GPL fans. Before you start yelling at me, I want to be very clear: I am a huge fan and supporter of the GPL.
I have licensed every piece of software I have ever written under the GPL, I have been an active financial supporter of the Free Software Foundation and Software Freedom Conservancy and the work they do, and I advocate for the usage of the GPL. My comments here are not about the validity or the great value of the GPL—it is an unquestionably great license—but more about the perception and interpretation of the license in the industry.
About four years ago, I was at an annual event called the Open Source Think Tank. This event was a small, intimate, annual gathering of executives in the open source industry in the California wine country. The event focused on networking, building alliances, and identifying and addressing industry problems.
At this event, there was a group case study in which the attendees were broken into smaller groups and asked to recommend an open source license for a real-world project that was building a core open source technology. Each group read back their recommendations, and I was surprised to see that every one of the 10 or so groups suggested a permissive license, and not one suggested the GPL.
I had seen an observational trend in the industry towards the Apache and MIT licenses, but this raised a red flag at the time about the understanding, acceptance, and comfort of the GPL in the open source industry.
It seems that in recent years that trend has continued. Aside from the Black Duck research, a license study in GitHub in 2015 found that the MIT license was a dominant choice. Even observationally in my work at XPRIZE (where we chose a license for the Global Learning XPRIZE), and my work as a community leadership consultant, I have seen a similar trend with many of my clients who feel uncomfortable licensing their code under GPL.