Legal possessors (6)
I believe the answer is:
owners
'legal possessors' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for owners that I've seen before include "Proprietors" , "Those in lawful possession, as of house" , "Legal possessors" , "Worsen for possessors" , "Holders, possessors" .)