  Physical design watermarking on contemporary integrated circuit (IC) layout
encodes signatures without considering the dense connections and design
constraints, which could lead to performance degradation on the watermarked
products. This paper presents ICMarks, a quality-preserving and robust
watermarking framework for modern IC physical design. ICMarks embeds unique
watermark signatures during the physical design's placement stage, thereby
authenticating the IC layout ownership. ICMarks's novelty lies in (i)
strategically identifying a region of cells to watermark with minimal impact on
the layout performance and (ii) a two-level watermarking framework for
augmented robustness toward potential removal and forging attacks. Extensive
evaluations on benchmarks of different design objectives and sizes validate
that ICMarks incurs no wirelength and timing metrics degradation, while
successfully proving ownership. Furthermore, we demonstrate ICMarks is robust
against two major watermarking attack categories, namely, watermark removal and
forging attacks; even if the adversaries have prior knowledge of the
watermarking schemes, the signatures cannot be removed without significantly
undermining the layout quality.
