
Open Source is written into the very DNA of PrestaShop: the source code of your favorite e-commerce solution is distributed under the Open Software License (and the Academic Free License), which allows PrestaShop’s source code to be used, modified and shared under defined terms and conditions.
Attorney and computer specialist Lawrence Rosen is the author of the licenses used by PrestaShop. We had the privilege of asking a few questions. Here’s what he had to say...:
Considering the number of licenses already available when you created the OSL and AFL licenses, could you give us your rationale for their creation?
I wanted to write a license (OSL) that provided the strength of the GPLv2 with clearer language and a better definition of "derivative works." I also wanted to create an academic license (AFL) with the strength of the Apache License with the exact same language as the OSL. I hoped this would make it easier for the public to understand how open source licenses work.
According to its Wikipedia article, one of the OSL’s most unique characteristics is its patent action termination clause, intended to dissuade users from filing patent infringement lawsuits. Would you say that this is the main interest of using the OSL?
I don't believe that the patent provisions are unique in effect. During the drafting of the OSL/AFL licenses, there were lots of discussions about how to craft an enforceable and meaningful patent grant and patent termination provision. Now many other open source licenses follow the same OSL/AFL pattern with different lawyer-chosen words.
In your article about OSL 3.0, in reference to forcing the disclosure of the source code, you write that "This ambiguity of the GPL is eliminated from OSL 3.0", which would explain why you see the OSL as superior to the GPL.
Using GPL code makes some developers/companies nervous because of its "contamination" effect. Would you say the OSL is less "contaminating" than the GPL is?
There is a long-term, widespread community argument about the reach of the GPL licenses to works that are independently written but aggregated (through some form of linking) to GPL code. Words like "contaminating" and "viral" and "infectious" are tossed into those discussions without clear definitions. As a result, some companies remain hesitant about using certain GPL software. That is a shame; much free GPL software is very good.
I hope for a court decision someday that will remove that GPL confusion.
The OSL/AFL licenses intend to eliminate such confusion. These licenses do not affect independently written code at all, no matter how aggregated.
Unlike the OSL license, the AFL license mentions that derivative works can use any other license that does not contradict its terms and conditions. Could you name some of these licenses?
Apache License, GPL licenses, MPL, EPL, etc., etc. The AFL license is very permissive.
A few projects have moved away from OSL in recent years: ClearCanvas moved to the GPL in 2013; CodeIgniter moved from a BSD-like license to OSL 3.0 in 2011, then switched to MIT in 2014; Mulgara still uses the OSL, but they require new code to be contributed using the Apache 2.0 license in order to eventually move to that license; Sparse moved to the MIT license in 2013.
While their reasons to move away from OSL are varied, most seem to move away from it in order to have more user contributions. Would you say it is a misunderstanding on their part?
I can't remotely judge the decisions that open source projects make about licenses. Nor do I feel compelled to push the OSL over other good licenses. I will say that BSD and MIT licenses are weak. They miss many provisions about patents and other important intellectual property issues. Why people keep using those licenses is a mystery. On the other hand, these licenses are compatible with each other for aggregations, so the world will have more open source software regardless of which licenses are chosen.
Drupal uses the GPL, and made it clear that plugins/modules and themes are derivative works of the core software, and that its PHP code must therefore be released under the GPL too (cf. Drupal policy). Would you say that OSL-using projects should work the same way?
Absolutely not. "Plugins/modules" and "themes" are not proper examples of "derivative works." I am waiting for a court to rule that way someday and quiet this GPL-induced confusion. In the meantime, an OSL project doesn't have that problem.
PrestaShop is distributed under the OSL 3.0 license, and chose to have its native modules licensed under the AFL 3.0 (see blogpost). Would you say this is the correct way to go?
That sounds reasonable but I can't remotely judge other's technical and licensing decisions. It wouldn't be fair of me even though I'm grateful that OSL and AFL were chosen.
The GNU project/FSF has a critical view of the OSL, writing that "distributing OSL software on ordinary FTP sites, sending patches to ordinary mailing lists, or storing the software in an ordinary version control system, is arguably a violation of the license". How would you respond to such claim?
Copies or derivative works of an OSL work must also be distributed under the OSL. The definition of distribution in the OSL includes the things mentioned by FSF. The strange thing is that the exact same rules would apply to GPL software. What are they complaining about?
Biography: Lawrence Rosen is both an attorney and a computer specialist. He is founding partner of Rosenlaw & Einschlag, a technology law firm that specializes in intellectual property protection, licensing and business transactions for technology companies. In addition to this law practice, Larry also served for many years as general counsel of the non-profit Open Source Initiative (OSI). He currently advises many open source companies and non-profit open source projects, including as member of the Apache Software Foundation and the Open Web Foundation. Larry's book, Open Source Licensing: Software Freedom and Intellectual Property Law, was published by Prentice Hall in 2004. He also taught Open Source Law at Stanford Law School. Larry often publishes and speaks around the world on open source and intellectual property issues.