corporate raider

from The Collaborative International Dictionary of English v.0.48

corporate raider \corporate raider\ n. (Finance)
   a person who purchases or attempts to purchase a controlling
   interest in a publicly-traded company against the wishes of
   the current management.

   Note: such a buyout is caled a {hostile takeover}.

   Syn: buyout specialist, takeover artist.
        [PJC]