Stitched circuitry region boundary identification for a stitched IC chip layout is presented along with a related IC chip and design structure. One method includes obtaining a circuit design for an integrated circuit (IC) chip layout that exceeds a size of a photolithography tool field, wherein the IC chip layout includes a stitched circuitry region; and modifying the IC chip layout to include a boundary identification identifying a boundary of the stitched circuitry region at which stitching occurs, wherein the boundary identification takes the form of a negative space in the IC chip layout. One IC chip may include a plurality of stitched circuitry regions; and a boundary identification identifying a boundary between a pair of the stitched circuitry regions, wherein the boundary identification takes the form of a negative space in a layer of the IC chip.