A shell (10) for a hearing device, and a method of producing the same. The shell (10) comprises a sub-shell (11) produced by a generative method, and a thermoformed hull (12) covering the subshell (11). The sub-shell (11) comprises lateral openings (13) covered by the thermoformed hull (12) so as to render the shell (10) more flexible in the region of the openings (13), and thereby to relieve pressure exerted by the shell (10) due to dynamic changes in the shape of the wearer's ear canal during jaw movement.