The paper outlines various measures of profitability and considers what role they can play in competition law. We argue that profitability measures can provide a good answer to the wrong question and a much less good answer to the question we really want to answer. Using appropriate definitions...

We provide a simple asymmetric information model showing that, in contrast to portfolio diversification arguments, there is a natural complementarity between executive options and stock ownership. Moreover, managers can be made worse off by being granted more executive options.