Cloning hedge fund indexes with liquid portfolios is hot these days. Major players, including Goldman Sachs, Morgan Stanley, Barclays, Societe Generale, and BNP Paribas, now offer hedge fund index clones. But guess what? These clones underperform the hedge fund indexes they were designed to replicate! The clone sponsors readily admit that, pointing to many technical reasons as to why that is the case (and a recent study by Ben Dor, Jagannathan, Meier, and Xu does a great job in explaining these). However, the most fundamental question is not usually mentioned at all – I mean, why is cloning expected to work in the first place?