By Ingrid Vandenborre & Caroline Janssens

Parity clauses, known as “most favored nation” or “MFN” clauses, used by online platforms to prevent their business users from offering their goods or services for better terms elsewhere, recently returned to the antitrust spotlight. MFNs had attracted scrutiny from competition authorities across the European Union between 2010 and 2015, leading to divergent approaches and outcomes, ranging from the prohibition of all, or only wide forms of MFNs, to restrictions based on the market power of the beneficiary of the MFN. Recent developments are reopening the debate on the competitiveness (or lack thereof) of MFNs and whether it is appropriate to allow narrow versions of the clauses.