This paper argues that European competition law does not allow for the definition of gratuitous markets, and that it is highly unlikely that free products/services can be included in markets with paid products/services. It is also argued that competition law does not apply to truly gratuitous exchanges (“de gratis non curat lex”). This does not mean, however, that free products should not be taken into account in the enforcement of competition law to paid products (e.g. when assessing market power). The conclusions rest on an overall analysis of the highly divergent and contradictory judicial and administrative practice, predominantly from EU legal orders, relating to a wide range of sectors, including TV, radio, print media, online services, software, telephone directories and payment cards.