An outer shell (1) for a joint socket implant, in particular for an acetabular implant, which comprises a convex outer face (3) and a concave inner face (4) for receiving an inner shell. The concave inner face (4) has at least partially a toothing system (7), in particular a circular circumferential region (6) thereof. Via the toothing system (7), an inhibition of the rotatability of the two shells, relative to one another, can be achieved upon insertion of the inner shell into the outer shell (1).