A method, system and computer program product are provided for implementing multiple mask lithography timing variation mitigation for a multiple mask polysilicon (PC) process. An application specific integrated circuit (ASIC) library includes at least one circuit device for a first mask, and at least one circuit device for a second mask. Critical hold time paths and critical setup time paths are identified in a circuit design. For critical hold time paths, circuit devices in the critical hold time paths are placed on a single mask of either the first mask or the second mask. For critical setup time paths, path delays are reduced by providing a mixture of circuit devices on the first mask and the second mask.