Plokite_Wolf: No, they own the whole IP, that's why Piranha Games is their licensee (see legal print). That happened when they absorbed FASA.
karnak1: Are you talking about the original FASA ips?
https://en.wikipedia.org/wiki/FASA_Studio I'm talking about the Battletech/MechWarrior/MechCommander IP. Microsoft acquired FASA in the 1990s and by transition holds the keys. That's the also the only reason MS' logo appeared in MechWarrior 3 that they had no other contributions to, for example. Piranha still answers to them for MWO and MW5.
karnak1: GOG is selling several games which were once licensed by Games Workshop. These publishers have since lost the license. Still the games can be sold.
Why can't the same apply to old Battletech licenses, like the Activision ones? I don't have a clue how these legal issues are settled, hence my questions.
Games Workshop's license has been given quite liberally throughout the years, and some of these titles are published by GOG themselves (e.g. Rites of War) just to have them out there.
Microsoft's stance on re-releases is different: unless they can make a remaster-y sort of thing, they just don't bother, especially not on a DRM-free platform. Hell, back in the days when games were re-released for budget prices in fugly keep cases, Microsoft let Ubisoft distribute the games so they didn't have to move a muscle.
They did hand MW4 Mercenaries to MekTek for a while, who distributed a modded version for free, but when they packed it in, they didn't care much. MW3 would need a real good patching to even have most users able to run it (it's horribly unstable), and I don't even know if they have the sources for MW1 and MW2.