US Patent 8732626 System and method of circuit layout for multiple cells

A method and system check a double patterning layout in abutting cells and switch the pattern in one of the cells if the edge patterns in each cell are in the same mask. The method includes receiving layout data having patterns in abutting cells, changing a designated mask in one cell if the edge patterns are in the same mask, adjusting cell edge spacings at a shared edge according to a minimum spacing rule and a G1-rule, and outputting a presentation of the layout data.