Abstract: In order to prevent the formation of flash and air bubbles on a gasket used to seal a filter element when the filter element is mounted in a housing to filter a fluid, a molding apparatus comprises first and second mold components cooperating to define a mold cavity positioned around the filter media formed by their respective mold surfaces and adapted to receive an expandable material forming the sealing gasket. The mold cavity includes a substantially semi-spherical ridge portion having an apex. The ridge portion of the mold cavity is formed by both the first and second mold components abutting each other at the apex of the ridge portion of the mold cavity along a mold line oriented at an angle to a central axis of symmetry of the mold apparatus. Moreover, mold surfaces of the mold components have upwardly sloping ramp surfaces for preventing trapped air bubbles.