Quote Originally Posted by Jack Mann View Post
Depends on why they don't wear it. The books are, to my knowledge, fairly unclear on this. If they truly object to the idea of metal armor, then probably not (but then, why are they so willing to travel with others who use it?), but if it's just a matter of allowing their powers to work, then they probably won't care if their animal companion wears metal armor or not. I suppose it's up to the DM as to why they're prohibited.
I believe that they can't wear metal 'cos of some oath they make to become a druid, presumably to the land or nature or something). Break the oath, nature gets pissed and takes away your powers for a day (naughty, naughty). Nothing there to say you can't touch metal or use it, just not wear it. No problem, technically, with letting an Animal Companion wear metal barding.