Posted June 25, 2015
Runic wrote on this post:
"Well, we partnered with [Humble] to do the ports for Mac and Linux. Can't say what it will be like in the future, but for now it's only available from HB."
http://forums.runicgames.com/viewtopic.php?f=30&t=60115&start=20#p506917
So it seems at best, the DRM-free versions are a timed-exclusive for Humble Bundle.
"Well, we partnered with [Humble] to do the ports for Mac and Linux. Can't say what it will be like in the future, but for now it's only available from HB."
http://forums.runicgames.com/viewtopic.php?f=30&t=60115&start=20#p506917
So it seems at best, the DRM-free versions are a timed-exclusive for Humble Bundle.