I have seen "Open Source" licenses which do not permit modification nor re-distribution. It's certainly not equivalent to the principle of Free Software.
Re:Acrobat Reader for Linux removed
by icebraining on Monday July 28, 2014 @03:59AM
(#8095639)
Ah, yes, there are "open source" licenses that don't follow the Open Source Initiative's definition. Still, Linux distributions tend to abide by it, as far as I know.
Virtually every open source application is also Free Software, and vice-versa. The most common licenses (GPL, BSD, MIT, Apache, etc) fit both definitions.