An actuation magnet is provided for moving a closure needle of a hot-runner nozzle of an injection molding tool. The actuation magnet has an armature which is coupled in movement to the closure needle and may be displaced between first and second cores by subjecting at least one coil to current. A permanent magnet is arranged in a manner such that it exerts an additional magnetic force on the armature in at least one, preferably two, movement directions.