Protecting the intellectual property of hardware and software artifacts is important for many business reasons, concede Qu (U. of Maryland) and Potkonjak (U. of California-Los Angeles), but they are into it for the elegance of the scientific and engineering challenge. They present in detail their newly developed constraint-based protection paradigm for protecting intellectual property in VLSI CAD. The basic idea is to superimpose additional constraints that correspond to an encrypted signature of the software designer in such a way that the quality of the design is only nominally impacted while strong proof of authorship is guaranteed. They have not indexed their work, perhaps finding that task not so elegant.