Boycotts consist in the elimination of a competitor by calling for measures of collective retaliation or by organizing a collective refusal to contract by application of an exclusivity clause. The implementing of a commercial policy reserving products or services to authorized customers in order to combat parallel trade can also characterize a boycott. Boycotts are amongst the most serious infringements of the rules of competition because they lead to the elimination of a competitor from the market: the anticompetitive character of such practices can be established purely from their object. Even the threat of a boycott can suffice. Lastly the infringement can be attributed to an undertaking without it having actually participated or even implemented the measures of the boycott.