The U.S. Horizontal Merger Guidelines and guidelines issued by enforcement agencies around the world employ the hypothetical monopolist paradigm to delineate relevant markets, but they provide only an imprecise and incomplete algorithm for implementing that paradigm. This paper fills the gap by...

The European Commission sought public comment on a revision of its Notice on the definition of the relevant market. Among other things, this contribution advises the Commission to: acknowledge the analytic purpose served by the relevant market in competitive assessment; apply the hypothetical...