Der er behov for særligt overbevisende beviser for, at der forekommer en blokering, når parterne kan have en fælles interesse i at hævde, at der forekommer en blokering, for derved at blive betragtet som ikke-konkurrenter, f.eks. når den påståede gensidige blokering vedrører teknologier, der teknologisk set er indbyrdes substituerbare.
Particularly convincing evidence of the existence of a blocking position is required where the parties may have a common interest in claiming the existence of a blocking position in order to be qualified as non-competitors, for instance where the claimed two-way blocking position concerns technologies that are technological substitutes.