{"id":1722,"date":"2013-04-02T12:51:14","date_gmt":"2013-04-02T17:51:14","guid":{"rendered":"http:\/\/redmonk.com\/dberkholz\/?p=1722"},"modified":"2013-04-19T21:23:50","modified_gmt":"2013-04-20T02:23:50","slug":"quantifying-the-shift-toward-permissive-licensing","status":"publish","type":"post","link":"https:\/\/redmonk.com\/dberkholz\/2013\/04\/02\/quantifying-the-shift-toward-permissive-licensing\/","title":{"rendered":"Quantifying the shift toward permissive licensing"},"content":{"rendered":"

The team at Ohloh<\/a> worked with me to organize a data hackfest at OSCON 2012, and we pulled together a great dataset that included licensing data for all open-source projects in Ohloh that had any commits in the past year. After working with Ohloh data for my recent post on language expressiveness<\/a>, I wanted to explore it in some different ways to see what else might emerge, and licensing seemed like one worth examining more deeply.<\/p>\n

My colleague Steve has posted about permissive vs copyleft licensing a number<\/a> of<\/a> times<\/a>, but we’ve never done quantitative research into licensing choice<\/strong>\u00a0to prove the extent to which any shifts are happening, the time frames involved, and the potential variations within different programming-language communities.<\/p>\n

Approach: Classification, history, and languages<\/h2>\n

Using the Ohloh data for 57,930 active projects as of July 2012, I classified the top 30 open-source licenses into one of three categories: permissive (e.g. BSD, Apache), limited (e.g. LGPL, MPL, EPL), or copyleft (e.g. GPL, AGPL).<\/strong> This three-category classification accounts for 90+% of all projects with specified licenses, which means it should be representative.\u00a0The total number of classified projects was 17,549, because a vast number of projects either have no license or Ohloh was unable to detect it.\u00a0Limited licensing is quite rare, hovering around 2%\u20133% of projects with licenses, so for the purposes of this post, we will focus on permissive and copyleft licensing.<\/p>\n

To attempt to identify historical shifts, I separated projects into buckets based on the date of their first commit. Since license changes between permissive and copyleft are quite rare, this should be a reasonable approach to examining trends over time.<\/p>\n

Since I hypothesized that programming language might also play a role, I further split each year’s bucket by language. Here, I’m going to focus on the 11 most popular languages according to our rankings<\/a>, as well as the total across all languages regardless of popularity. Any data points with 5 or fewer projects between permissive and copyleft are not shown, to remove noise.<\/p>\n

Results: A clear trend toward permissiveness<\/h2>\n

I’m showing the data as a ratio between permissive and copyleft licensing to account for changes in absolute numbers of projects over time. Any number above 1 indicates a bias toward permissive licensing, while any number below one indicates a bias toward copyleft.<\/strong><\/p>\n

\"sort_license_class_by_year\"<\/a><\/p>\n

 <\/p>\n

Remarkably, every single language shows an upward trend, starting either in favor of copyleft or near equilibrium and shifting upward in a more permissive direction.<\/strong> The overall total, shown as a thick black line, further supports and clarifies this trend since the individual languages can be rather noisy.<\/p>\n

Two languages of particular note are the two extremes: Ruby on the permissive side and Perl on the copyleft side. While most languages cluster relatively tightly, Ruby rises far above them with a very clear and strengthening shift toward permissive licensing \u2014 2x in favor of permissive in 2010, 6x in 2011, and 11x in 2012.<\/strong> At the other extreme, Perl shows a roughly 2x\u20133x bias in favor of copyleft<\/strong>, which is distinctly below the nearest neighbor, C++, but not nearly as large of a divergence from the primary cluster as Ruby shows.<\/p>\n

Other than that, at the level of individual languages, it’s difficult to draw any strong conclusions based on their relative positions because they are much less distinct. More recent web-development languages (Ruby, JavaScript, Python) may bias toward permissiveness, as do languages that tend to be used on closed platforms (Obj-C, C#). The difference between Java, C, and C++ is likely cultural as well, with C and C++ being common in the copyleft community while Java is less so due to inertia from its OSS-unfriendly past.<\/p>\n

Conclusions<\/h2>\n

The shift toward permissive open-source licensing is dramatic over the past decade. Since 2010, this trend has reached a point where permissive is more likely than copyleft for a new open-source project.<\/strong> Although there are language-specific effects, especially in the case of Ruby, the overall movement is clear. Outside the extremes, new projects in even the most copyleft-biased language (C++) in 2012 were given copyleft licenses less than 60% of the time.<\/p>\n

Disclosure<\/strong>: Black Duck Software (which owns Ohloh) is a client.<\/em><\/span><\/p>\n

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The team at Ohloh worked with me to organize a data hackfest at OSCON 2012, and we pulled together a great dataset that included licensing data for all open-source projects in Ohloh that had any commits in the past year. After working with Ohloh data for my recent post on language expressiveness, I wanted to<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[3,7,10,13],"tags":[],"class_list":["post-1722","post","type-post","status-publish","format-standard","hentry","category-adoption","category-data-science","category-licensing","category-open-source"],"jetpack_featured_media_url":"","jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p23Tsn-rM","_links":{"self":[{"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/posts\/1722","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/comments?post=1722"}],"version-history":[{"count":0,"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/posts\/1722\/revisions"}],"wp:attachment":[{"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/media?parent=1722"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/categories?post=1722"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/redmonk.com\/dberkholz\/wp-json\/wp\/v2\/tags?post=1722"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}