An integrated circuit (IC) manufacturing method includes receiving an IC design layout having IC regions separate from each other. Each of the IC regions includes an initial IC pattern that is substantially identical among the IC regions. The method further includes identifying a group of IC regions from the IC regions. All IC regions in the group have a substantially same location effect, which is introduced by global locations of the IC regions on the IC design layout. The method further includes performing a correction process to a first IC region in the group, modifying the initial IC pattern in the first IC region into a first corrected IC pattern. The correction process includes using a computer program to correct location effect. The method further includes replacing the initial IC pattern in a second IC region in the group with the first corrected IC pattern.