Almost nothing inspires a spirited discussion among the open source faithful as much as introducing a new open source license, or a major change in an existing license’s terms. In the case of version 3 of the GPL, the update process took years and involved dozens of lawyers in addition to community members. So, it’s no surprise that the pot is already boiling over something called the ???Commons Clause.??? How energetically? Well, one blog entry posted yesterday was titled The Commons Clause Will Destroy Open Source. The spark that turned up the heat was the announcement the same day by RedisLabs that it was adopting the license language. The clause itself is short (you can find it here, together with an explanatory FAQ). It was drafted by Heather Meeker, an attorney with long open source involvement, in conjunction with ???a group of developers behind many of the world’s most popular open source projects.??? It’s also simple in concept: basically, it gives a developer the right to make sure no one can make money out of her code – whether by selling, hosting, or supporting it – unless the Commons Clause code is a minor part of a larger software product. In one way, that’s in the spirit of a copyleft license (i.e., a prohibition on commercial interests taking advantage of a programmer’s willingness to make her code available for free), but it also violates the ???Four Freedoms??? of Free and Open Source software as well as the Open Source Definition by placing restrictions on reuse, among other issues. And that’s where things start to get interesting.