A corpaeration is Technically a Civillian organization, But they Most certainly have more firepower than any other civillian organizations. Trying to say "your CIVILLIAN HAVE SUCKY STUFFS" simly dosent work anymore, if it ever did.
I have a memory of bar rumours from impoverished Rheinland corp escorts talking about how they moonlighted as mercs to pay the bills. They're civilians but they aren't feebs or anything. Probably lots of ex-cops/ex-military as people have said.
I don't think one has many legs to stand on when discussing civilians in space. There are noncombatants in a conflict, but seeing as every last ship is armed and dangerous, I don't suppose the concept applies.
The EIC comparison is one I'll hark back to, for a couple interesting reasons. At sea, especially back then, ships were considered sovereign territory, and any ship was armed, whether it be a merchantman, sloop, Manila Galleon, or ship of the line. They were all of them armed, what's more, with the same sort of weaponry, and many nations considered their merchantmen extensions of their navies.
The vasty deeps, of sea or space, don't make room for quaint notions like civilian law, or civilians. Civilians happen in the settlements around the edges, the domes put up against the night. Those men and women who live aboard the boats are their own nation-states, capable and dangerous in their own right, because they are the ones who fly out into the same space that the pirates haunt, that the wars are waged..and it isn't so civilized as to make room for anyone not ready to defend themselves. Civilians cannot exist.