1. « A SSNIP Test for two-sided Markets » by Lapo Filistrucchi Discussant: Bruno Karoubi Télécom Paris

2. The Relevant Market problem  Defining the relevant market is a major issue for antitrust authorities.  All the more true when goods are horizontally differentiated (wrist watches and pocket watches, proprietary payment cards vs. non proprietary payment cards…).  Market power is inversely proportional to price elasticity. Evaluating empirical price elasticities.  Which set of goods can be deemed to constitute an independent market? mergers’ interests is to consider it as big as possible.

3. The SSNIP Test is irrelevant for TSM  The SSNIP test: the relevant market is supposed to be as small as possible. simulating the effect of a small but significant increase of price (cf. Federal Trade Commission and Department of Justice guidelines). if this price increase reduces profits, the relevant market is extended to a marginal set of goods and the first step is repeated.  The relevant market is the smallest one in which a price increase has no effect on profits.

4. Adapting the SSNIP test to TSMs  Two examples of TSM: “payment card” (PC) (when there is a transaction between two end consumers) and “media type” (when there is no transaction).  While a good relevant to one side is necessarily relevant to the other in PC market type, this is not necessarily true in M-type market.

5. Future researches  Application of the SNIPP test to TSM in PC and M- type markets.  The data set that will be used for M-type markets has already been collected, while surveys are carried out in the Netherlands in order to build the one that will be used for PC-type markets.