Transfer some firm overseas (4)
I believe the answer is:
move
'transfer' is the definition.
(I know that transfer is a more specific form of the action move)
'some firm overseas' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'MOVE' is hidden within 'firm overseas'.
(Other definitions for move that I've seen before include "Depart" , "Change location" , "Affect" , "Relocate" , "Change address" .)