A method includes receiving a design layout file for an integrated circuit device in a computing apparatus. The design layout file specifies dimensions of a plurality of features. The design layout file is decomposed to a plurality of colored layout files, each colored layout file representing a particular reticle in a multiple patterning process. Each of the colored layout files is retargeted separately in the computing apparatus to generate a plurality of retargeted colored layout files. Retargeting each of the colored layout files includes increasing dimensions of a first plurality of features based on spacings between the first plurality of features and adjacent features. The retargeted layout files are combined to generate a combined layout file. Features in the combined layout file are retargeted in the computing apparatus to increase dimensions of a second plurality of features based on spacings between the second plurality of features and adjacent features.