"...The GNU GPL is not an “open source” license except that the Open Source Initiative organization placed the GPL on a list of approved licenses. This is trivial in comparison to writing and maintaining the license. The GPL was written by the Free Software Foundation, an organization which tells us that they “are not against the Open Source movement, but we don’t want to be lumped in with them” because there are real and significant philosophical differences between the two groups, differences that sometimes lead to radically different conclusions about the harm of proprietary software..."