Paradox Interactive. Everything they release is DRM-free, their forums are by far the most intelligent and pleasant I've seen of any publisher or dev house, constant engagement with fans, continual support of older titles up to and including free patches that add new features, LAN support for titles with multiplayer, amazing mod support in their in-house titles (practically everything is exposed as text files and bitmaps, ready to be changed however one pleases), and very hands-off with their third-party titles. Granted, they've had their fiascos (buggy releases mostly, though their QA has since improved and they always do their best to fix things when they go wrong.) But they're still pretty much the best around.
I know I sound like a cult member, but that's kinda the beauty of it: Pdox's whole business model revolves around making their fans as rabidly loyal as possible. They accept that piracy will happen no matter what, so their strategy is to make as many people as possible like them so much that they won't pirate.
To wit, I got into them when they put EU3 Chronicles (the base game + all 5 expansions) on sale for $3. (A year after that, maybe 2-3 years after the 5th expansion came out, they released a patch that added new features.) That $3 sale, plus the vibrant forums, plus all the goodwill they have for their fans, made me a customer for life: I've since bought six or seven other titles by them and plan to preorder EU4. I'm the type of person who never preorders (and rarely even buys anything until reading tons of reviews and until the first sale or price drop), but I'd have no problem dropping money on EU4 sight unseen. Ofc, they've posted like 20 dev diaries and at least a dozen videos, but I'd still pick it up even if I hadn't seen them.
But yeah, there was one forum thread that I think sums up their approach. Someone posted asking when some game would come out, since it'd been in dev for a while but didn't have a release date. This was a game that Paradox was publishing but not developing. One Pdox's executive producers replied to the thread saying, "It'll come out when the developers say it's ready." Cue mass adulation.
ilu pdox <3