n="30"The invention relates to an implantable valve (1) for a drainage device for draining cerebrospinal fluid, having: a valve housing (10) which has an inlet (2), an outlet (3) and an interior (4)； a valve body arrangement (600) movably disposed in the interior (4)； a first valve seat (5), the valve body arrangement (600) being designed to bear on the first valve seat (5) so as to close a flow connection between the inlet (2) and the interior (4) of the valve housing (10)； a second valve seat (7) which lies opposite the first valve seat (5), the valve body arrangement (600) being designed to bear on the second valve seat (7) so as to close a flow connection between the outlet (3) and the interior (4) of the valve housing (10)； and a spring mechanism (800) which is disposed in the interior (4) and exerts a spring force on the valve body arrangement (600) in the direction of the first valve seat (5).
