While there is no doubt that a professional association of undertakings, which is likely to constitute the vehicle of a cartel, may also be a party to it, there is room for some hesitation in the case of trade unions responsible for defending the interests of their members. The former Competition Council and the Paris Court of Appeal considered themselves fully competent to sanction an anticompetitive boycott commitment in a collective labor agreement.

Collective agreements have a specific status which is not reduced to a concurrence of wills but which borrows from both a mutual understanding and a unilateral act. They are said to be half-contractual, half-regulatory in nature, the latter being particularly marked in the case of an extended agreement, but also present in the case of an ordinary agreement. According to the Paris Court of Appeal, while the Competition Authority has the power to sanction anticompetitive commitments, regardless of the nature of the agreement in which they are found, it does not have the power to assess the legality of the extension process.

What criterion makes it possible to differentiate between the provisions of a collective agreement that fall under competition law and those that do not? It seems that the only possible criterion is a substantive one. Only those provisions of collective agreements which go beyond the object of the agreement, i.e. the fixing of salaries, working conditions and social benefits, and which lead, for example, to the boycotting of other undertakings, would be subject to competition law. Under this interpretation, collective agreements would be excluded from the scope of competition law, not because they do not represent a concurrence of wills, but rather because their purpose is not to coordinate the behavior of undertakings on the market, with labor relations being regarded as non-market relations.