On 24 February 2006, the Syndicat des Librairies Francophones de Belgique (SLFB), the union representing the French-speaking book resellers in Belgium, filed a complaint against Interforum and Dilibel.

Interforum and Dilibel are the exclusive marketeer-distributors for Belgium of the large French book publishers Editis and Hachette Livre, respectively. According to SLFB, they both account for the distribution of 60% of books published in France sold in Belgium. The price invoiced by Dilibel and Interforum to Belgian booksellers is based on the French public price set under the “Loi Lang”, to which a mark up is applied, imposed by the public authorities, in order to allow the distributor to cover its distribution costs peculiar to the Belgian market.

According to SLFB, the application of this mark up by Interforum and Dilibel amounted to collusion in relation to the fixation of their distribution costs, with the aim to increase prices of books imported from France. SLFB also claimed this practice amounted to an abuse of dominance as the distributors imposed excessive prices on booksellers on the Belgian market for books imported books from France.

In their decision, the Competition Prosecutors first rejected the geographic market definition proposed by SLFB and, further to a market consultation, followed the market definitions set out by the European Commission in its Lagardère/Natexis/VUP decision, which differentiates between several markets including marketing, distribution and direct sales by the publishers to the booksellers. In that case, the European Commission held that all of these markets were larger than national, covering Belgium, France and Luxembourg.

The Competition Prosecutors then held that the investigation had not established collusion between Interforum and Dilibel, as they both apply a different mark-up calculated according to different criteria and were therefore unable to align themselves on a single distribution cost price level. As regards the alleged abuse of dominance, the Competition Prosecutors found that no elements pointed in that direction, in particular since Interforum and Dilibel's market shares were below 30% and the investigation had demonstrated that publishers using Interforum and Dilibel as a marketeer-distributor were able to work with alternative marketeer-distributors without any difficulties. The complaint of SLFB was therefore rejected.