Design information related to an irrelevant area of a first layer of semiconductor article may be received. The first layer may be manufactured by illuminating a lithographic mask during a lithographic process. First layer information associated with an outcome or an expected outcome of the illuminating of the lithographic mask during the lithographic process may be received. Information corresponding to a layout of an irrelevant area may be identified in the first layer information. A differentiating attribute that differentiates the layout of the irrelevant area from a layout of a relevant area of the first layer of the semiconductor article may be identified. The differentiating attribute may be used to determine one or more other irrelevant areas of the first layer of the semiconductor article.