http://www.project1999.com/forums/showthread.php?t=2651
Kill Stealing
Kill Stealing can be defined as the intentional engagement by a player to a mob that is
already engaged by other un-allied players, or a mob that clearly
belongs to a player/group's area of claim.
If its not a camp, then you must determine who actually has the engage rights aka FTE. Gaining experience does not equal mob rights.
Hope this helps.