While some games offered on impulse do have activation limits as 'copy protection' (which is norm listed at the top left under download size ect.) I highly doubt that is true at least for GalCiv since it is an actual stardock game and well stardock is renown for not puting dumb stuff like that on their games.
The games on impulse that do have 'drm' protection of that kind are not games actually made by stardock but third party publishers/developers like Ubisoft or EA. I'm guessing that to license stardock to sell thier games they require that its under the condition whichever type of drm that third party uses for thier game has to also be used on impulse versions. Also, its almost always listed as what type of drm is used by that particular program and if its not listed as having a protection type I belive that means it has none which is how all the actual stardock games like GalCiv show up.
