A case for a gas turbine engine incudes a radial flange with a partial scallop along an inner diameter of the radial flange. A case assembly for a gas turbine engine incudes a first case with an a first radial flange with a partial scallop along an inner diameter of the first radial flange, the partial scallop adjacent to a first aperture thorough the first radial flange and a second case with an a second radial flange with a second aperture thorough the second radial flange the second radial flange mountable to the first radial flange at an interface such that the second aperture is axially aligned with the first aperture and a seal lip that extends from the second case interfaces with said first case at a longitudinal interface