The claiming change is actually pretty interesting, and everyone was scratching their heads as to what the heck actually happened.
I was on the boat from Al Zhabi to Nashmau when someone fished up an Oberon. I believe they were solo, and were slowly dealing damage to it. At around 60%, it unclaims. I'm not sure why... I don't think the person fighting it died. Now at this point everyone on the boat is trying to claim it. Everyone was hitting it and using provoke and casting spells, etc, but it stayed unclaimed (yes it was losing life). Finally a group (that had more hate than the person initially fighting, I presume) claimed it and killed it.
I wonder what would've happened if it died in an unclaimed state.