Market Definition of Online Platforms in the New Economy: Another Foggy Day

Platforms, or online platforms in the new economy, have become one of the difficult topics in competition law and policy around the world. Online platforms have a number of distinctive features that make competitive assessments difficult, such as the two (or multi-)sided market. The traditional method of defining the relevant market is the appraisal of substitutability on the demand side, while considering other factors like switching costs, etc. However, this legal and economic tool may not work for the market definition of an online platform. Despite the existing difficulties, the EU and the US have provided some guidance for the market definition in the area of online platforms by developing case law and policy on the digital economy. This article aims to discuss the recent developments involving the market definition of online platforms, thereby suggesting a future policy for the Korean competition regime.